SL.NO. C O N T E N T S PAGE NO.1.0 1ST CLASS (METALL – RESTRICTED)- 2009.1.1 Explain the terms planning, organizing and control. How an effective

manager of a large opencast mechanized mine can skillfully plan, organize and control activities in day-to-day as well as long term basis

1.2 A large mechanized working is advancing towards a village. How are you going to determine safe charge limits for blasting to safe guard the interest of the villagers? What are the permissible standards of ground vibrations for different types of structures?

1.3 In processing plant of a large opencast iron ore mine one skilled technician of a contractor was killed due to fall from height while attending breakdown. Write a detailed accident enquiry report assuming your own conditions. Suggest steps to prevent recurrence of such accidents

1.4 State the provisions of Indian Electricity Rules, 1956, of the following:(a) Clearance above ground of lowest conductor.(b) Plans (c) Protective equipments

1.5 Elaborate the terms EIA and EMP. What threats are posed to environment by surface mining activities? What steps do you suggest for mitigation of the same.

1.6 Write short notes on: -(a) Appointment of officers and competent persons.(b) Danger from surface water. (c) Occupational Health Surveillance. (d) Canteen Managing Committee.

1.7 What are the harmful effects of noise? State its permissible levels. As a manager of a large open cast iron ore mine with workshop and beneficiation plan what steps would you take to safeguard workers from noise induced, health and operational problems.

2.0 2nd CLASS (METALL – RESTRICTED)- 2009.2.1 Prepare a Safe Operating Procedure (SOP) for removal of 1 million

tones of overburden per month with outsourced shovel dumper system.

2.2And old (about 30m high) overburden dump situated within 5m. of the quarry edge slide with a portion of the top bench ( in soft alluvium) and the second bench ( in unconsolidated strata) to the bottom bench burying three blasting helper deployed for charging holes.

Write a report of enquiry assuming your own conditions2.3 Write short notes on any four of the follow:

a) Storage and transport of explosives.b) General requirement about the mine plan and sections.c) Apparatus under pressure.d) Place of accident.

e) Appointment of officials and competent persons. 2.4 a) What are the new diseases proposed to be included in the list of

Notified diseases. What changes do your suggest in the Occupational Health Surveillance system to comply with the recommendations of the 10th Safety Conference.

b) What facilities shall be provided to the Inspector for Occupational Health Survey?

2.5 The number of accidents in mechanized opencast mine during transportation of ore and also in the ore beneficiation plants are increasing. State the probable reasons for increase in accident and enumerate the preventive measures to be adopted for the same

2.6 In view of recent terrorist activities around mining areas what change do you suggest in procurement, storage and safe use of explosives. What other methods do you suggest for winning minerals avoiding traditional blasting system. Explain brief.

2.7 Write short notes on –a) Working and examination of machinery.b) Plans & sections to be submitted after abandonment or

discontinuance.c) Appointment of engineers.

d) Emergency plan.3.0 1ST CLASS (METALL – UNRESTRICTED)- 2009.3.1 Write notes on any three of the following:

a. General lighting in opencast workings.b. Precautions in case of sockets etc.c. Medical attention in case of injury.d. Notices of diseases.

e. Notice & Order under Section 22 of the Mines Act, 1952.3.2 A highly mechanized underground mine is planned to produce 5000

tones of ROM per day. A processing plant required to be installed in the leasehold area. Assuming your own conditions prepare an environment plan, keeping in view different factors affecting the environment.

3.3 A large number of accidents/incidences are occurring due to hard landing of cages in different mines at frequent interval. List out the failures and remedial measures to prevent recurrence of such accidents/incidences. Assume your own conditions.

3.4 Prepare a safety management plan for a large open cast mine. Assume your own conditions.

3.5 Write short notes on any two of the following:a. Winding rope, factor of safety, maintenance.b. Continuous environmental monitoring instrument in

underground mines. c. Mechanical ventilator, fan water gauge, efficiency of fan.

3.6 Are we moving on the right track in reducing accidents in the mines? Discuss. Describe different potent tools used by management for reducing accidents in underground mines due to fall of roof & sides.

3.7 During development (2.4m x 2.4 m) a 800 m long footwall drive for connecting ore passes of a blast hole sub-level stope, a Rocker shovel operator entered in the face for loading blasted rock mass and collapsed. Giving reason, write an enquiry report stating how such accidents can be prevented in future.

3.8 Due to large number of accidents a mine is declared as accident –prone. As a manager of the mine, suggest measures you will adopt to make the mine safer and accident free.

4.0 2nd CLASS (METALL – UNRESTRICTED)- 2009.

4.1 Describe provision of the Mines Act and the Mines Rules in respect of following:a) Quality, quantity and storage of drinking water in mines. b) First Aid Stationc) Notice of certain diseasesd) Employment of persons below 18 years of age.

e) Certifying surgeon. 4.2 What are the benefits of risk analysis based safety management

system? What is the status of implementation of safety management system in Metalliferous Mines in our country? Give strategies of efficient implementation of safety management system.

4.3 Write short notes on the follow:a) Post detonating fumes. b) Advantages of bulk loading of explosives in underground

and opencast metal mines. c) Shock tube based delay initiation system for underground

and opencast mental mines. 4.4 Describe the occurrences of following gases in underground metal

mines and their physiological effects:a) Nitrous fumes b) Hydrogen sulphide.c) Carbon monoxide.

4.5 What is environment management plan? Describe salient features of environment management plan?

4.6 (a) What is “restricted earth neutral system”- explain.(b) What is maximum permissible earth fault current as per IER-1956 for-

(i) Open case mine(ii) Underground mine.

(c) Describe provisions of IER-1956 regarding earthling of electrical equipment in underground metalliferous mines

4.7 Electrically operated L.H.D. is used in an underground mine producing about 0.5 million tonne of ore by practicing cut and fill method of stopping. Prepare a “code of practice” for deployment of such LHD, with emphasis of its operations on filled up area. Assume Footwall and Hanging wall rock to strong.

4.8 An underground mine is located near a seasonal river. Describe in detail, what precautions would you take to prevent inundation in the mines

THE MINES ACT, 1952 Morning Session

EXAMINATION FOR MINE MANAGER’S CERTIFICATE OF COMPETENCYRESTRICTED TO MINES HAVING OPEN CAST WORKINGS ONLY UNDER THE

METALLIFEROUS MINES REGULATIONS, 1961

FIRST CLASS

MINE MANAGEMENT, LEGISLATION & GENERAL SAFETY (RESTRICTED)

SUNDAY, THE 4th OCTOBER, 2009 Full Marks: 100 Time : 2 ½ Hours

Answer any FIVE Questions(All questions carry equal marks)

………………………..

Q1. Explain the terms planning, organizing and control. How an effective manager of a large opencast mechanized mine can skillfully plan, organize and control activities in day-to-day as well as long term basis.

Ans:- A Manager deals with human beings and gets his job done through and with people. Basically the job of a manager is to direct the activities and the people under him to reach pre-determined objectives with the optimum use of the resources available to him. The job of a manager can be looked upon as a process involving basically five steps, namely.i) Planning, which is concerned with achieving the desired results or goals;ii) Organizing; which is aimed at integrating the available factors into an

optimum relationship with a view to effectuate the plan;iii) Staffing, which seeks to select and develop the right type of personnel;iv) Motivating, which aims at inspiring and inducing the people within the

organization to direct their efforts towards the implementation of the plans, and

v) Controlling, which periodically evaluates performance and attempts to ensure that the activities are actually executed in consonance with the plan.

Planning:- Planning involves selecting missions and objectives and the actions to achieve them, it requires decision making which is choosing future course of action from the alternatives. It is basically plotting the use of time, resources and efforts towards the realization of what management derives to accomplish. Realistic planning is based upon an accurate analysis of present resources, past performance, present situation and future goals. It is the pre-action stage and a blueprint for future activities. The function of management planning is both general and specific, both long term & short term. Organizing: - Organizing is that part of managing that involves establishing an intentional structure of role for people to fill in an organization. It is intentional in the sense of making sure that all the tasks necessary to accomplish goals are assigned and it is hoped, assigned to the people who can evacuate them best.

It is the arrangement of the work of individual and groups, and the provision of the facilities necessary for doing that work in such a way that the best, most efficient and economical results will be obtained. When an organization is planned it should be sufficiently flexible to allow for change and expansion.

Organizing is also thought as: the identification and classification of required activities; the grouping of activities necessary to attain objectives; the assignment of each grouping to a manager with the authority

necessary to supervise it, and the provision for co-ordination horizontally and vertically in the

organization;Controlling: - The managerial function of controlling is the measurement and correction of performance in order to make sure that enterprise objectives and the plans devised to attain them are being accomplished. Planning and controlling are closely related. Without objectives and plans, control is not possible because performance has to be measured against some established criteria.Controlling is measuring and correcting individual and organizational performance to ensure that events conform plans. It involves measuring performance against goals and plans showing where deviations from standards exist and helping to correct deviations from standards. In short, controlling facilitates the accomplishment of plans. Although planning must proceed controlling, plans are not self-achieving. Plans guide managers in the use of resources to accomplish specific goals; then activities are checked to determine whether they conform to the plans. The basic purpose of controlling includes the following:-

to clarify and project desired results more accurately. to identify and forecast major trends and the probable need for changes in

significant areas. to detect operating problems in time to take corrective action before they

become critical. to provide continuous guides for improving performance and conserving

time and effort.Control involves the comparison of actual performance with some determined criterion. Obviously, budgeting is a control device, because manager compares the actual costs and revenues with the budgeted norms. Other accounting techniques that provide manager with control information arei. Standard costs- These are predetermined costs developed from the past

experience, motion and time study, expected future production costs or some combination of theses.

ii. Responsibility accounting- In this costs are identified with those individuals who are responsible for their control.

In taking managerial decisions, the manager has to select from the different alternative courses of action available to him in terms of the objectives he is seeking to achieve. Thus a good manager tries to plan, organize & control his activities in such a way that he makes things happen. The effective manager makes things happen through an adequate system of planning and there after so using the resources available to him that the plans are implemented effectively.An effective manager of a large O/C mechanized mine can skillfully plan, organize and control activities in day to day as well as long term basic in following manners:-i) Target setting:- After obtaining statutory permission from DGMS for deep hole blasting, the manager will set target for extraction of mineral taking into consideration thickness of ore body, reef width, stoping width, size of blocks to be stopped etc. Subsequently, man power, machinery and materials shall be

skillfully planned, organized and controlled by the manager for achieving the target already set in. For controlling the activities and judging the performance, the actual achievements shall be compared with budgeted norms. ii) Deployment of men & machinery:- In order to achieve targeted production & ensuring safe operation in large open cast mechanized mine, matching men ( statutory & non statutory ) and machinery such as shovels, drills, dozers & dumpers etc shall be engaged in rational manner as per provision of approved project report.iii) Preparation of Plan:- Based on availability of mineral resources, working plan shall be prepared and all activities in day to day and long term basis shall conform to this Plan.iv) Setting criteria for use of heavy machinery / deep hole blasting:- As required under Reg. 106(2) of MMR 1961, the following action shall be taken:a) Bench geometry – The height & width of benches in OB ore body or other

rock formation shall not be more than the permissible limits as permitted by DGMS in permission letter. To comply with this, bench geometry shall be maintained in safe manner in order to avoid collapse of benches. For control, manager shall engage surveyor for measuring and record keeping of the bench geometry & the same shall be checked by manager personally time to time.

b) Roads for truck & dumpers etc:- All roads from the O/C workings shall be arranged to provide one way traffic. If not possible, no roads shall be of a width less than 3 times the width of largest vehicle plying on that road unless definite turnouts and waiting points are designed. Manager shall ensure this provision by passing necessary instructions to surveyor and engineer in charge of the project.

c) Supervision- During every production shift, the O/C workings shall be placed under the charge of an ACM possessing 1st class certificate & during maintenance shift the workings shall be placed under the charge of Engineer in charge.

d) Drilling, blasting & charging of blast holes:- Manager shall plan, organize and control all activities related to drilling, blasting & charging of short holes including transport of explosives. If necessary, scientific agency shall be engaged for practicing controlled blasting technique.No blasting shall be planned during dark hours and thunderstorm. In order to control fly rocks, ground vibration, noise etc, the charge per delay and charge per round shall be fixed based on blasting vibration study. The blast vibration study shall be conducted on day-to-day basis and the results thereof shall be compared with the permissible limits for prevailing condition and incase of any deviation, preventive measures shall be taken.

e) General Lighting:- In dark hours, sufficient lighting arrangements shall be provided & maintained as recommended by DGMS.

f) Operation of machinery:- Only skilled, competent and sincere workmen shall be authorized to operate the machinery. The availability and utilization of machinery shall be compared with set standard norms. In case of any deviation, maintenance schedule must be prepared and implemented in order to increase its availability and utilization to optimum level.

g) Precaution against noise & dust:- Adequate arrangements to allay dry dust by wetting shall be planned and organized during any operation of drilling, loading, unloading , crushing etc. Also suitable steps must be planned and organized by manager by all appropriate means to reduce the exposure of

workers to any excessive noise and vibration. The plan should also include the dust and noise survey at frequent intervals.v) Framing of traffic rules:- The code of traffic rules for regulating the movement of heavy machinery ( commensurate with the capacity / size and type of machines), incorporating procedures, speed limits, right of way, parking & standing, overtaking, signs, mechanical condition of vehicles etc shall be planned, organized and implemented by the managers in mechanized open cast mines.vi) Framing of code of practice for prevention of injuries to persons engaged in tipping and dumping operation:- The Manager shall plan, frame & implement code of practice for prevention of injuries to persons engaged in tipping and dumping operation clearly indicating hazards, responsibilities of mine officials, safe operation of equipment and machinery etc.vii) Consumption of POL, explosives and other consumables:- In order to control the excess consumption of POL, explosives and other consumables, manager shall compare the actual consumption against the norms. In case of any deviation from norms, necessary instruction must be past and implemented.

Q2. A large mechanized working is advancing towards a village. How are you going to determine safe charge limits for blasting to safe guard the interest of the villagers? What are the permissible standards of ground vibrations for different types of structures?

Ans:- Ground vibrations due to blasting are a potential problem for the mining and construction industries, the public living near the mining activities and the regulatory agencies responsible for setting safety and environmental standards. Blast vibration effects depend primarily on vibration levels and frequencies and to a lesser degree on site and structure specific factors. Vibrations generated due to detonation of explosives may cause damage to structure and annoyance to their residence in the vicinity of the mines.The vibrations radiating from the blast holes while passing through surface structures induce vibration on the structures causing resonance. The components of ground motion can affect the structures through compression and tension and also through vertical and horizontal shearing effects.

Determination of safe charge limits for blasting to safe guard the interest of the villagers:Damage to any buildings and surface structure due to blast vibration can best be explained in terms of its response to the passing vibrations. One of the critical response factors is the amount of differential movement that occurs between structural members causing strains, which in turn, produce cracking. Investigation into cause of damage to buildings & surface structure due to O/C blasting showed that the structural resonance responded to low frequency ground vibrations, resulting into increased displacement & strain. Experimentally, it has been verified that if the wavelength of the transmitting wave is long enough compared to the size of the structure (low phase angle) the entire structure tend to move generally as one.In India, peak particle velocity (PPV) and frequency of wave has been considered as the best criterion for evaluating blast vibration in terms of its potential to cause damage.In order to determine safe charge limits for blasting to safe guard the interest of the villagers, the following objectives are taken into account:

i) To evolve a suitable blast parameters and estimate safe charge to control flying fragments within 10m in any direction from the sources of blast.

ii) To establish safe charge and distance relationship through on site measurements of vibration levels within threshold value of PPV.

iii) To determine the extent of safe extension of existing surface mine within a radius of 300m but beyond 100m of neighbouring structure / houses based on established system of blasting parameters.

Methodology for experimental blasting for measurement of blast induced ground vibrations:To predict the extent of damage, determine safe charge limits and to take preventive measures, it is necessary to measure ground vibration due to blasting as per following details:i) Instrumentation:- For determining safe charge limits for given PPV, frequency and scaled distance from the site of blast, Instantel Blastmate ll and Blast mate lll vibration monitors having tri-axial transducers shall be used. It measures Peak Particle Velocity (PPV) in three mutually perpendicular directions i.e. longitudinal, transverse and vertical along with respective frequencies. Depending on the distance between the blasting site and blast monitoring / instrumentation point, variable sampling speed is to be used to capture the representative blast induced wave. ii) Method – The transducers shall be placed near the structure on the solid undisturbed ground and should be placed well in contact with the ground. For structural response, the transducers shall be placed horizontally over the wall, floors and ceilings. A minimum of 15 points of observations corresponding to a minimum of 10 blasts shall be made for better prediction with a high index of determination.iii) Experimentation- Adequate care shall be taken while designing the blast parameters in mineral and OB benches in respect of blast design, proper use of explosives, maximum charge / delay, max. charge / round, length of stemming column for controlling flying fragments within 10m in any direction and minimizing the level of ground vibration within safe limit. The initiation shall be done by Nonels.A plan showing structures belonging to owner & not belonging to owner in different colours shall be prepared. The plan shall incorporate details of construction of structures in the tabular form. It should also show 100m, 200m and 300m zones from the structures, the place of experimental study and the limit up-to which blasting is proposed to continue. The least mean square method of regression analysis shall be used to interpret the data. The square root scale distance shall be used for analysis and interpretation of data.The following equation shall be used for determination of max. charge weight / delay for given PPV

V = KR /Q max- b

Where, V= peak particle velocity (mm/s) K, b = site constants to be determined by regression analysis

R = distance of the measuring transducer from the blasting face (m)Qmax = explosive’s maximum weight per delay (kg)

Taking log on both sides of above equation, we get

log(v) = logk + (-b)log(R /Q max) -----------------(i)

From 10 blasts, 15 observations are recorded at different distances from blast site to measure PPV along with corresponding frequencies. The log values of PPV (v) and log values of distance (R) over square root of explosive charge (Qmax) called as scaled distance is plotted in graph to know the behavior of the vibration measured.

The PPV(V), maximum explosive charge/delay (Qmax) and the distance (R) between blasting site and vibration monitoring stations are grouped together and by least mean square root method of regression analysis, a propagation equation valid for the site i.e. site specific propagation equation, is established in the form of a square root sealed distance formula as given in equation (i) in which k & b are regression co-efficient having values

K = 47.80b = (-)0.8097

The representative regression equation/predictor equation to predict ground vibration for a given sealed distance may be approximated by

log (V) = -0.8097(SD) + 1.6795 ---------------------------(ii)For given PPV, scaled distance can be determined from equation (ii). After having determined SD, the max. charge limit, Qmax may be calculated by the following relation:

SD = R /Q max

Permissible standards of ground vibrations for different types of structures- Depending on the type of structures and dominant excitation frequency, the peak particle velocity (ppv) on the ground adjacent to the structures shall not exceed the values given below in the table:

Type of structure Peak particle velocity (mm/s)Frequency (< 8 Hz)

Frequency (8-25 Hz)

Frequency (>25 Hz)

(A) Buildings/Structures not belonging to the owneri) Domestic houses/structures( Kuchcha, brick & cement)

5 10 15

ii) Industrial buildings 10 20 25iii) Objects of historical importance & sensitive structures.

2 5 10

(A) Buildings belonging to owner with limited span of lifei) Domestic houses/structures 10 15 25ii) Industrial buildings 15 25 50

Q3. In processing plant of a large opencast iron ore mine one skilled technician of a contractor was killed due to fall from height while attending breakdown. Write a detailed accident enquiry report assuming your own conditions. Suggest steps to prevent recurrence of such accidents.

Ans:- Enquiry Report

Ref.No……………………… Date………….…...

To,The Manager,“ A “ OC (Iron Ore)

Sub:- Enquiry report in respect of fatal accident involving 1 skilled technician of a contractor in A-open cast

working due to fall from height while attending breakdown in a processing plant.

Dear Sir,

As desired vide your letter no………………… dt…………… I am enclosing herewith the detailed enquiry report in respect of fatal accident involving 1 skilled technician of a contractor in A-open cast working due to fall from height while attending breakdown in a processing plant indicating the cause and circumstances attending to the accident, contraventions of statutory provisions, responsibilities and suggestions to prevent similar accident in future in Annex.l . I am also enclosing the accident plan showing the site of accident along-with photographs.

Yours faithfully,Encl: As above.

(Safety officer) “A” OCP

Annexure - l

Detailed Enquiry Report

Assumption of Conditions:-

A processing plant has been installed in big iron ore OCP being worked with shovel dumper combination using deep hole blasting after obtaining statutory permission for extraction of ore by OC method from DGMS.

I _______________, Safety Officer, A OCP inspected the place, where this accident occurred and enquired into the cause and circumstances connected with the same.

1) Introduction & information :- The accident occurred in a processing plant installed in A OCP of M/s……. on ……… at about 11.30 A.M. in 1 st causing death of 1 skilled technician of a contractor while attending brake down in the plant.

2) Background information:- The iron ore is extracted from A-OCP & transported to processing plant for beneficiation of the same as per planning.

3) Occurrence of accident:- At about 11.30 A.M., one of the worker’s noticed that a person deployed by contractors was falling from a height of 11m when he was engaged for attending breakdown in the beneficiation plant.

4) Cause of Accident:- After inspection of site of accident, recording of statements of co-workers and other officials it was revealed that accident occurred due to the following reasons:-i) While at work with a safety belt the deceased who was standing precariously on a projected bamboo fixed at its end to a steel trust lost his balance and fell down. The resultant jerks served the safety belt causing his free fall.ii) Failure to comply with some elementary safety precautions like providing platform/stage or scaffold, ensuring use of approved and well-maintained safety belt etc. 5) Contraventions of statutory provisions:- In my opinion, the following statutory provisions were contravened:i) Reg. 181 of MMR,1961 – The skill technician deployed by contractor contravened the statutory provisions in respect of general safety.ii) Reg. 44(3) of MMR,1961- Sufficient supply of proper materials and appliances for ensuring safety of persons not provided by Mine Manager.

6)Responsibilities:- Enquiry into the accident revealed that if the proper materials and safety appliances were provided by the mine management the accident could have been averted. The following persons are considered responsible for the accident:- i) Manager- In contravention of provisions of reg. 44(3) of MMR 1961, the Manager failed to supply proper materials and appliances for ensuring safety of persons.

ii) Skilled Technician - He failed to ensure safety provisions regarding general safety.

7) Suggestions to prevent similar accident in future:- In my opinion, the following suggestions should be implemented in order to avoid repetition of similar accidents in future:i) A working platform/stage or scaffold of adequate width with proper fencing shall be provided. A safe means of access to the working platform shall be provided.ii) Only approved type of safety belt or life line conforming to Indian standard IS:3520-1999 shall be used which shall be properly maintained and checked for its fitness before every use.iii) A code of safe procedure shall be prepared and implemented for such type of dangerous jobs, which amongst other may include training of persons, supervision before engaging contractual persons etc.iv) General safety- a) Whenever it is necessary to work at height

Persons working below shall be warned Area below the overhead place shall be cordoned off by rope and A danger board “DANGER-MEN WORKING ABOVE’ shall be

suitably placed.b) The work shall be done during day light hours or the area shall be properly illuminated.c) Tools shall be carried in a tool kit. No material or tool shall be dropped or allowed to be dropped from any height.

v) Selection of persons- Persons engaged on such jobs shall be trained in safety and must

be medically fit. Persons working at height shall obtain a “Height Pass from the

work in-charge.vi) Inspection Checklist:- A system of 3-tier inspection by contractor’s supervisor, departmental

supervisor and engineer at regular intervals shall be instituted. The following checks shall be made before use:a) Sturdiness of approach ladders, scaffoldings, platforms, railings, toe boards etcb) Provision and sturdiness of structure for anchoring life line of the safety belt.

c) Openings, gaps etc on floors at height. d) Obstruction on walkways, passages etc. e) Illumination, ventilation and weather conditions. f)Temporary electric power line laid in close proximity to scaffolding,

platform, structure etc. g) Winches, pulleys, shackles, ropes, telephones, derricks and other lifting

equipment for their fitness.

Q4. State the provisions of Indian Electricity Rules, 1956, of the following:(a) Clearance above ground of lowest conductor.(b) Plans(c) Protective equipments.

Ans:- (a) Clearance above ground of lowest conductor:- Rule 77 of the Indian Electricity Rules, 1956 makes provision for clearance

above ground of lowest conductor. 1) According to this rule, conductor of an overhead line including service lines erected across and along any street as well as elsewhere than along or across any street shall at any point be at a minimum height as given below: Type of line Minimum Clearance (m)

Across the Along the Elsewhere street street along or across

i) Low & medium voltage lines 5.8 5.5 High voltage lines 6.1 5.8ii) All voltage up-to 11KV, if bare 4.6

All voltage up-to 11KV, if insulated 4.0 High voltage lines >11KV up-to 33KV 5.2

2) For extra high voltage lines, the clearance above ground shall not be less than 5.2m plus 0.3m for every 33 KV or part by which the voltage of the line exceeds 33KV. However, the minimum clearance along and across any street shall not be less than 6.1m.As recommended by DGMS, no coal depots and dumps of ash and debris or any other material should be made in the vicinity of the overhead lines which may results in reduction of the prescribed minimum clearance from the ground.

Ans:- (b) Plans- Rule 112 of IER,1956 stipulates provisions for maintenance of plans which are enumerated below:1) A correct plan, on the same scale as the mine plan as per regulation showing the position of all fixed apparatus and conductors therein (other than lights, telecommunication or signaling apparatus & cables for the same) shall be prepared, maintained and available in the office at the mine.2) A similar plan / mine plan on the scale not less than 25cm. to a Km (1: 4000) showing supply lines, conductors, equipments and cables shall also be kept by the manager or owner of the mine.3) A similar plan on such scale as directed by Central Government, showing the position of all electric supply lines, shall be kept in the office of any licensee or other person transmitting or distributing energy in a mine.4) All the above-mentioned plans shall be examined and corrected as often as necessary to keep them reasonably up-to-date. The dates of such examinations shall be entered thereon by the manager or owner of the mine & such plans shall be available to the inspector, or an Inspector of Mines at any time.

Ans:-c) Protective equipment:- To guard against dangers of electricity, protective equipments should be incorporated in electrical installations. Rule 116 of IER1956 stipulates following statutory provisions in this regard:1. In the interest of safety, appropriate equipment (switchgear with necessary protective devices) shall be suitably placed in the mine for automatically disconnecting supply to any part of the system, where a fault including an earth fault occurs. Fault current shall not be more than 750miliamps in 550/1100-volt systems for under ground and 50amps in 3.3 KV systems in open cast mines. The magnitude of the earth fault current shall be limited to these specified values by employing suitably designed restricted neutral system of power supply.

2. The operation of the switchgear and the relays shall be recorded daily at the generating station, sub-station or switch station in a register kept for the purpose.3. The effectiveness of the switchgear and the protective system shall always be kept and maintained in working order, shall be checked once every 3 moths and the result thereof shall be recorded in a separate register kept for the purpose.

Q5. Elaborate the terms EIA and EMP. What threats are posed to environment by surface mining activities? What steps do you suggest for mitigation of the same.

Ans:- Mining operations damage the environment and ecology to an unacceptable degree unless carefully planned and controlled. There is a need for balance between mining and environmental requirements.The ministry of environment and forests has come out with a new EIA Notification called EIA Notification, 2006 on 14th September, 2006. As per this notification, all the mines having leasehold of 5-50 ha are categorized under “B” category and require environmental clearance from concerned State Government. The mine leases of 50 ha or more are considered to be causing significant impact and are categorized under ‘A’ category. Such projects are required to obtain prior environmental clearances from Ministry of Environment & Forests, Govt. of India.The principal aim of an EIA is to ensure that likely environmental problems are taken into consideration at the planning & design stager of the project. In India, a report called an “Environmental Management Plan (EMP)” is prepared at the end of the EIA study and this is submitted to MOEF as part of an application for environmental clearance of the project.

In general, the process of obtaining environmental clearances may be categorized under two heads, the first one being filing of Form –l and preparation of Terms of Reference (TOR) of EIA report and second one being preparation of EIA report based on TOR approved by MOEF. The approval of TOR provide a platform of interaction between project proponent and the regulatory authority i.e. MOEF. Hence the various issues which require deliberations are discussed and frozen. So, the sensitive environmental issues are taken up for detailed study in EIA report. So, a mechanism of dialogue exists in the current EIA Notifications. Secondly, the process of public hearing has been made more pragmatic. Public hearing had been one of the major bottlenecks in the EIA process and possibly one of the major factors in getting the environmental clearance delayed. Now this process has been streamlined and alterative has also been suggested to ensure public hearing. Thus, an element of public participation exists in the current EIA process.Environmental impact Assessments (EIA): It is a systematic study carried out with the objective of assessing the likely environmental implications of a proposed human activity. Such activities may include building an irrigation project or a factory or development a mine.EIA is, in its simplest form, a planning tool that is generally regarded as an integral component of sound decision-making. As a planning tool it has both information gathering and decision making component which provides the decision maker with an objective basis for granting or denying approval for a proposed development project. Its main purpose is to give the environment its due place in the decision making process by clearly evaluating the environmental consequences of a proposed activity before action is taken.Key elements of EIA:

a) Scoping : Identifying key issues and concerns of all the stakeholders.b) Screening: Deciding whether an EIA is required based on the information

collected.c) Identifying & evaluating alternatives: Listing alternative sites and

techniques and the impacts of each.d) Mitigating measures: Reviewing proposed actions to prevent or minimize

the potential adverse effects of the project and e) Issuing environmental statements: Reporting the findings of the EIA. Objectives of EIA

Broadly the objective of EIA is to estimate the likely impacts of any developmental project/ activity on the various environmental components. Hence, it is imperative:

To find out the suitability of the area for mining operations and to delineate areas where mining should not be done.

To devise the mining standards to be followed in respect of suitable mining methods, this can be applied with minimum degradation.

Major Issues in EIA For all mining projects EIA is mandatory. The major issues in EIA process for

mining industry are: Identification of impacts to be assessed Assessment of impacts Completion of an appraisal and Enabling the objectivity in appraisal.

From the technical point of view, EIA can be considered as a data management process. It has three components. Firstly, the appropriate information necessary for a particular decision to be taken must be identified and possibly collected. Secondly, changes in environmental parameters resulting from the implementation of the project must be determined and compared with the situation likely to accrue without the project. Finally, actual changes must be recorded and analyzed. Environmental management plan- An EMP of a mine is in fact a guiding plan for undertaking the mining and associated activities with due regard to the environmental protection and management in and around the mining complexes. The EMP outlines the various actions that are required to be taken in mitigation of the environmental impacts of mining. The EMP is based mainly on the prevailing environmental scenario, the proposed mining and associated activities and assessment of their impacts on the various environmental attributes. Hence, the study of the prevailing environmental scenario should be accurate and exhaustive so that the mining activities can be planned accordingly and the assessment of the impacts is realistic.Objectives of EMP:EMP for Mining Project is essentially Environmental Readiness Document, which has to fulfill following objectives:o Conform to National and Regional environmental policies and priorities.o Attainment of National and Regional environmental performance Standards.o Compliance with environmental statute, mine rules and instructions of DGMS

governing mining operations in an environmentally compatible manner.o Assessment of pre-mining environmental scenario and environmental

impacts arising out of various mining operations for different mining technology options.

o Pollution control Technology and Mined Land Reclamation Alternatives and identifications of Cost effective technology including assessment of funds for environmental management of the mining project.

o Action plan (time bound) for environmental management of the mining project.

CONTENTS OF EMP

This should include the following:i) Introduction:- The Project, Objectives of EMP, Environmental Management Priorities & Plan of Actionii) Description of the mining project-The Overall project., Project location, extent, starting & time schedule, target and phased mineral production, project cost etc, Project facilities, communication ( road network, railway), Project requirements: Land, Water, Transport, Services, Housing. project constructing & Project Operation and phasing.iii) Environmental Management & Land Reclamation Objectives.iv) Base Line Environmental Data, Site description:- Topography, drainage, meteorological conditions, land classification and use., Four season data on ambient air, noise and water quality over adequate number of stations, Surroundings: Land use, population, and infrastructure, Socio-economic profile covering population (sex-wise and age-wise) distribution, literacy level, occupation and income pattern, crops and their yield, migration tendency etc., Inventory of flora and fauna with special reference to endangered species of flora and fauna, Special Topics as Relevant: Soils, vegetation, water balance, hydrology, atmospheric conditions, Where forest land is involved, all information and data relating to evaluation of loss of forests, cost benefit analysis, as elaborated in the guidelines under The Forest (Conservation) Act.v) Environmental Impact Assessment: Socio-economic profile, Air Pollution, water pollution., Noise Pollution, Ecology and habitat, ground vibration, vi) Mitigation of hazards: Management of Air Pollution, Water Pollution, noise pollution, Management of Socio-Economic Environment, Land degradation & ground vibration.vii) EMP Implementation & Monitoring.Threats to environment by surface mining activities & mitigation - Surface mining activities pose threats to environment in big way. It damages a large land surface area, air quality, water quality, displace people from their ancestral homesteads & cause agriculture loses. Surface mining requires large areas of land to be temporarily disturbed. This raises a number of environmental challenges, including soil erosion, dust, nose and water pollution and impacts on local biodiversity. Steps are taken in modern mining operations to minimize these impacts. Good planning and environmental management minimizes the impact of mining on the environment and helps to preserve biodiversity.Following are the threats / impacts on environment due to surface mining activities and their mitigation:i) Impact on air quality:- The surface mining operation like drilling , blasting, movement of HEMM on haul roads, collection, transportation and handling of ore / mineral, screening, sizing and segregation in its are measures sources of fugitive emission of solid & gaseous pollutants deteriorating air quality. It creates an air pollution problem not only within the mining premises but also in surrounding residential area affecting abundant air quality.Mitigation –

Using dust extractors with drills Optimizing blast design for proper fragmentation & minimizing the dust

generation. Water spraying on haul roads . Using suitable designed water sprays at the transfer points to suppress

the dust. Black topping of service roads. Use of dust musk by operators Planning for development of green belts around the areas having

mining and associated activities. Planning for the formation of soil stacks & OB dumps in such a manner

that the contribution of these activities towards the concentration of SPM in the ambient air is minimum.

Using air pollution control systems in the washeries and enclosed CHPs

ii) Impact on water quality:-Mining and associated activities have quantitative as well as qualitative impacts on the water regime in an around surface mining complexes. The water seeping into the mine and collected in the mine sump is partly used up in the mine and the excess quantity is discharged into the surface drainage system. Water in the nearby water bodies gets polluted due to leaching from OB dumps, discharge of pumped out mine water and effluents discharge from mineral processing plants. During rainy season the run off water from the area surrounding the mines may carry with it a large doze of suspended solids into the nearby water bodies. Acidic water results in severe water pollution problems. Acid mine drainage refers to distinctive types of water bodies that originate from the weathering and leaching of sulphide minerals.Mitigation –

Construction of sewage treatment plants (STP) in the township with the activated SLUDGE process.

Construction of industrial effluent treatment plants (ETPs) in the down flow line of the workshop as well as mine effluent discharges.

Provision of silt arrestors/siltation ponds/sedimentation ponds in the mining area.

iii) Impact on land use:- Surface mine activities affect the land in various ways like removal of top soil, dumpling of solid wastes, cutting of roads, creation of derelict land etc. These impacts are briefly outline here under:-

The land-use pattern undergoes a change due to constructions and infrastructure development, digging of open pits and dumping of OB rock mass in the form of the heaps.

Leachates from OB dumps & other rock masses and polluted water from the pits affect the characteristics of the top-soil affecting the land use.

The agricultural land has been lost not only in the mining area but also get disturbed in the nearby areas due to air and water pollution.

Disturbances in the effective land-use due to damage to the surface, sub-surface and underground water bodies.

To- soil has been removed & thus during the post mining reclamation soil fertility has been lost if the top-soils are not restored properly.

Mitigation – Designing the mining and associated activities for the minimum

possible land requirement.

Design the mining activities in such a manner that the changes in the surface drainage pattern are minimum.

Planning the mine with decommissioning, closure, reclamation and rehabilitation so that the land after mining can be brought in economic uses.

Making provisions for separate removal and handling of top and sub-soils so that these can be re-laid at the timer of reclamation for developing the land uses of the reclaimed surface.

iv) Impact on ecology-The impact of surface mining activities on ecology i.e. human beings, flora and fauna are as under:

Removal of all vegetation (flora) and thereby fauna from the area required for mining and other associated activities.

Pollution of water in the surrounding water bodies due to leaching from overburden dumps, effluents discharge from coal washeries affects the aquatic ecology of these water bodies.

Air pollution contributed by mining affects the growth of the plants. Noise and vibration due to blasting, operation of the heavy machines and

coal processing plants affects wild animals and birds in the nearby forests. Top-soil in tensile zones of subsiding areas may loose its vegetation

supporting capability.Mitigation –

Planning mining layout so as to have the least requirement of the forestland and taking necessary steps for reclamation of the mined out land so that the forest land taken for the mining purposes can be brought back to forest use.

Developing a suitable compensatory forest. Cutting the threes to the minimum possible extent and preserving the

flora. It would be appropriate to uproot the trees and plants and then establish them at suitable locations, may be in the areas earmarked for compensatory afforestation.

Developing a flora bank to preserve the typical floral species of the area so that these can be replanted and developed as and when needed.

The noise and vibration producing activities in the mines and the associated activities be planned to have the minimum possible intensity and impact on the wild life in the surrounding area.

v) Impact of noise & vibration -Continuous operation of HEMM in the surface mining activity is the primary source of noise & vibration problem in the mines and surrounding areas. The impacts of noise are noise induced hearing loss of workers, decreased work performance, communications disturbance, sleep disturbance, increase in blood pressure etc. Wild life is more sensitive to noise & vibrations than the hum beings. Mitigation –

Minimizing noise and vibrations by controlled blasting technique & using vibration isolators in equipments.

Developing green belts around colonies and mining areas. Proper maintenance and lubricating of HEMM. Developing of culture to wear earmuffs during working period near the

noise prone areas.

Q6. Write short notes on: -

(a) Appointment of officers and competent persons.(b) Danger from surface water.(c) Occupational Health Surveillance.(d) Canteen Managing Committee.

Ans:- a) Appointment of officers and competent persons:- As per provision of section 18 of Mines Act’1952, it is obligatory on the part of mine management to take necessary steps besides making financial provisions for compliance of statutory provisions so as to ensure safe operation in mines. For this purpose,

1) i). The mine management shall appoint such number of competent persons, including officials and technicians, as is sufficient to secure during each of the working shifts-

adequate inspection of the mine and of the equipment; a through supervision of all operations in the mine; the installation, running and maintenance, in safe working order, of

all machinery in the mine and the enforcement of the requirements of the statute.However, DGMS may require the appointment of such number of

additional competent persons by the mine management as he considers necessary.

ii) (a) Where the mine is worked on more than one shift, the mine management shall ensure that, during the afternoon shift and the night shift, the mine is under the general supervision of an assistant manager or underground manager, if any, and of an experienced mine foreman in other cases.

2) It shall be the responsibility of the manager to see that the persons so appointed are competent to perform the duties assigned to them. No person shall be so appointed unless he is paid by the owner or agent and is answerable to the manager.

3) Copies of all appointment made shall be entered in a bound paged book kept for the purpose. A list of all such competent persons shall also be maintained.

4) Every manager on taking over charge of a mine shall satisfy himself that all persons already appointed for the purpose are competent to perform the duties assigned to them, and if he finds them competent, he shall either countersign their authorizations or issue fresh ones.

Ans:- (b) Danger from surface water- Water available on surface is a potential source of danger for any mine whether underground or open cast. In the history of Indian mining, there are instances on record in respect of drowning of mines from surface source of water. The legal provisions have been made in the statute to guard against danger from surface water. Reg.127 of MMR’1961, stipulates the details in this regards which are given below:(1) Where any mine is so situated that there is any danger of in rush of surface water into the mine adequate protection against such inrush shall be provided and maintained. If any dispute arises as to whether such protection is adequate or not, it shall be referred to the Chief Inspector for decision.(2) No workings shall be made in any mine vertically below:

i) any part of any river, canal, lake, tank or other surface reservoir or ii) any spot lying within horizontal distance of 15 m from either bank of

river or canal or from the boundary of a lake, tank or other surface reservoir.

except with the permission in writing of the Chief Inspector and subject to such conditions as he may specify therein.

Every application for obtaining permission shall be accompanied by two copies of a plan and section showing the existing position of the workings of the mine, the proposed layout of workings, the depth of the workings from the surface, the position and depth of any stoped-out area in the neighbour hood, all faults and other geological disturbances and such other particulars as may effect the safety of the mine or of the persons employed therein.In addition to above, detailed precautionary measures against danger of inundation should be laid down while working beneath or in the vicinity of rivers and major surface water bodies, particularly during the rainy season. This may include framing and implementing standing orders for safe with-drawl of persons, provision of float alarm as a means of warming in case of rise in water level in the river in addition to river guards and an effective and speedy communication system which can function even independent of electricity and work in adverse conditions.

Ans:- (c) Occupational Health Surveillance:- Surveillance is “continued watchfulness over the distribution and trends of disease incidence through the systematic collection, consolidation and evaluation of morbidity and morality report and other relevant data”, as well as the timely dissemination of data “to all who need to know”.It deals with the monitoring of occurrence of occupational diseases and the work environment factors responsible for the diseases. Traditionally, occupational diseases prevention activities adopted a factor-to-factor approach based on one to one relationship linking certain classical disease of occupation such as pneumoconiosis to dust, hearing impairment to noise, poisoning to exposure to heavy metal dust, etc., the approach is still valid in the context of Indian Mining Industry. Through, dust related diseases still remain one of the most important occupational diseases, diseases related to other occupational hazards like noise, vibration, chemicals etc, are becoming more and more predominant among the mining employees of the industry.Occupational Health surveillance can be categorized into two broad categories;a) Environmental surveillance, which deals with identification of various health

hazards at work place and quantification of them.b) Medical and Biological surveillance, which deals with early diagnosis of

occupational diseases amongst employees through periodic health screening process, which includes physical examinations of employees along with relevant investigative procedure at fixed intervals.In addition to procedure like dust survey already mentioned in the statute, it is proposed to conduct following environmental & medical and biological surveillance in every mine at periodic intervals: 1) Proposed environmental surveillance:

i) Noise mapping of various work places in the mine premises based on the various machines being used in concerned mines along with personal noise dosimetry of individual workmen exposed to noise level above 85 dbA. ii) Vibration studies of various mining machinery including drills, SDLs, LHDs, excavators, motor graders, dumpers, etc.

iii) Ergonomic assessment of all latest machines, before their introduction into mining operation. Ergonomical assessment should include:

Assessment of work process Assessment of working aids/tools Assessment of working posture

iv) Potability test of drinking water supplied to the mine employees, to be made mandatory once in a year irrespective of its source, the sample of water to be collected from the points of consumption.

2) Proposed medical & biological surveillance:A medical surveillance programme should be such that the occupational

diseases are detected at early stage, and further deterioration in the health of the worker can be checked, suitable rehabilitative measures are taken and control measures are adopted to prevent the occurrence in future. For this purpose following actions should be taken:

i) IME should be made mandatory for all mining employees whether permanent, temporary or contractual, before they are engaged in any mining job.

ii) The frequency of PME should be brought down from existing 5 yrs to 2 yrs for the mining employees above 45 yrs of age.

iii) Each mechanized mine should engage at least one qualified medical officer for every 500 employees and thereafter, one for every 1000 employees.

iv) One of the medical examinations of every person should be arranged within one year of his superannuation.

v) Standards IME & PME shall be suitably modified in order to ensure early diagnosis of diseases caused due to employment in mines.

vi) Special tests should be included in the PME for employees exposed to specific health hazard.

Q7. What are the harmful effects of noise? State its permissible levels. As a manager of a large open cast iron ore mine with workshop and beneficiation plan what steps would you take to safeguard workers from noise induced, health and operational problems.Ans:- A sound without agreeable musical quality is called noise. Any unwanted or undesired sound is noise. Human ear can defect sound in the frequency range of 16HZ. It is an abrupt sound of complex character with an irregular period and amplitude originating from a source in a non-periodic motion.The growth of mechanization and increased usage of HEMM have led to a noisy environment both in UG as well as in OC mines. The impact of noise on miners in UG mines is very high due to confinement (enclosed atmosphere). On the other hand, in surface mining (open atmosphere) the impact of noise is not only on miners but also on the people in vicinity. Noise is emerging as an important and challenging health hazards for mine workers.Harmful effects of noise- It is well known that exposure to noise may interfere with speech communication, cause annoyance and distraction. It may also reduce output and efficiency and cause fatigue apart from various health disorders unrelated to the effects on the hearing. Harmful effects of noise may be classified as follows:i) Pathological effect- Hearing loss, reduction of speech intelligibility Acoustic traumas, auditory fatigueii) Physiological effect- Changes in blood pressure, Changes in pulse rate Constriction of blood vessels, Dilation of the pupil of eye Changes in blood cholesterol contentsiii) Psycological effect. Feeling of discomforts, Sleeping interference Reduced intellectual performance, Fatigue, nervous irritability & strain, Vexation, Irritation distress, Mental disorder

In certain circumstances, noise may cause a decreased electrical resistance in the scheme, reduction of gastric activity or electro-myographic evidence of reduced muscle tension.

The degree of injury from exposures to noise depends upon a no. of factors such as intensity and frequency range, duration of exposures and individual susceptibility.

Recommended noise standards/ permissible levels of noise:-The main objectives of setting noise levels are : To prevent a risk of hearing impairment To prevent interference of communication essential for safety purposes and To eliminate nervous fatigue with due consideration to the work to be done.

Based on the ILO code of practice, the DGMS has recommended the following noise standards:Srl.No.

Limit Noise level in dBA

Effect

1 Warning Limit

85 Level below which very little risk to an unprotected ear for an 8 hours exposure

2 Danger limit

90 Level above which the danger of hearing impairment & deafness may result to an unprotected ear for an 8-hour exposure.

115 Worker should not allow, without appropriate ear protection.

120 Personal protective equipment shall be worn if the noise is fast.

130 Personal protective equipment shall be worn if there are single isolated outbursts of noise

140 No worker shall be allowed to enter an area where the noise level exceeds the limit.

Measures for noise control and reduction of noise exposure:As a manager of a large open cast iron ore mine with workshop and beneficiation plan, I shall take following steps to safeguard workers from noise induced, health and operational problems: a) Engineering Measures (noise control)-

For new machinery, laying down noise levels in specifications of machinery to be purchased. Acceptance level could be 85-90-dB (A) in normal operation of the machine at the operator’s position.

In case of existing machinery, conducting noise zone survey, reducing noise at source.

Interrupting the noise path by putting acoustics noise barriers or enclosures, isolating men from the source by acoustic cabins & using remote control equipment.

Modification / changing the work process to reduce noise output. Increasing the distance between the source and the receiver. Proper mounting of machines / flexible mounting / balancing of machine.

b) Administrative measures (reducing noise exposure)- Noise exposure can be reduced by:

reduction of exposure time at noisy operation by changing the operator at set intervals.

job rotation during a shift or on a day to day basis. changing the orientation of work activity with respect to receiver.

c) Hearing protection:When all engineering and administrative measures fail to reduce noise to acceptable levels or as a short-term measure, hearing may be protected by ear protectors such as use of earplugs, earmuffs and noise helmets and other sophisticated ear protectors.In addition to the above mitigative measures, a long term strategy and comprehensive hearing conservation programme should be formulated and implemented incorporating the following components:i) Noise level surveys including noise exposure dose profile of workers.ii) Engineering & Administrative controls.iii) Awareness & Health Promotion Programmes on Noise and its effects.iv) Personal Hearing Protection.

v) Audiometric Examination of workers.vi) Maintenance of comprehensive records of noise level surveysvii) Periodic monitoring and review of hearing conservation programme.

Regular audiometry as a part of periodic medical examination of workers will show to what extent the measures have been successful.

THE MINES ACT, 1952 Afternoon Session

EXAMINATION FOR MINE MANAGER’S CERTIFICATE OF COMPETENCYRESTRICTED TO MINES HAVING OPEN CAST WORKINGS ONLY UNDER THE

METALLIFEROUS MINES REGULATIONS,1961

SECOND CLASS

MINE MANAGEMENT, LEGISLATION & GENERAL SAFETY(RESTRICTED)

SUNDAY, THE 4th OCTOBER, 2009 Full Marks: 100 Time : 2 ½ Hours

Answer any FIVE Questions(All questions carry equal marks)

………………………..

Q1. Prepare a Safe Operating Procedure (SOP) for removal of 1 million tones of overburden per month with outsourced shovel dumper system.

Ans:- Conditions given:OBR to be handled : 1 mt/month = 12 mt/year. Machinery deployed : Outsourced shovel dumper combination.Conditions assumed: No of benches in OB: 5Dip of Strata: 1 in 14

No of Machines deployed; Shovels(10 m3) : 10 Nos., Dumpers(85te) :35 Nos, Drills(150mm): 10 Nos., Dozers: 05 Nos., Road Graders:02Nos. etc.

There is an increasing trend of contractual work in metal mines in India in recent years. This is due to need of introduction of modern mining, access to specialized expertise and need to continually improve efficiency in the face of strong national and international competition, especially in view of entry of private entrepreneurs and multinational companies.In recent past, the rate of accidents has increased in Indian Mines, particularly in outsourcing patches in which mining operations are carried out by engaging contractors men & machines. Thus management of safety issues becomes an essentiality for mine operators. Improvement in contractor worker’s safety performance will play a significant role in the industries overall performance. Mine Operators must ensure that work is carried out in compliance with the existing statute. Any system of work established by the contractor must be consistent with the mine operators, and it is the responsibility of mine operator to determine the safety standards. For this purpose, safe work procedure or safe operating procedure as recommended by 10th National Conference on Safety in Mines is required to be prepared by the mine operator and also by contractors for strict enforcement in the mines.

For ensuring strict enforcement of statutory provision by the workers of the hired contractors, the code of practice / safe operating procedure for safety of contractor workers and machinery shall be as follows:

Sl.No. Item Practice to be followed1 Training: All

contractors’ workers engaged on surface & OC mines to be trained.

(i) Before commencement of work against work order contractor shall give to the manager a list of his workers /supervisor to be trained as per VTl Rules and new VT module.(ii) Persons required to be trained, shall be sent for training by Manager.(iii) A list of trained workers already available with the contractors shall be furnished to be Manager.

2 Medical Examination

All persons to be deployed shall undergo IME and PME.

3 Record in “B” Form

Manager shall ensure that records of contractors workers are maintained in Form – ‘B’ as per stature.

4 Supervision Statutory supervision of contractual operation by departmental competent persons to be ensured by Manager/Project Officer.

5 Issue of Identity Cards

(i)Contractors shall issue identity card to all workers under him.(ii) Contractor shall be bound not to employee any persons whom the Manager/Agent has reason to believe that the person’s actions are unsafe to the mining operations or who contravenes the provisions of Mines Act, Rules and Regulations framed there under.

6 Attendance/ Working hours/ rest day

Manager to ensure:(i) Attendance of contractors workers shall be recorded in the Form-D/E as per Mines Rules.(ii) Working time on every day shall be limited to 8 hours spread over to a maximum of 12 hours working shift. Weekly days of rest shall be ensured.

7 Rest Shelters Contractors shall arrange for rest shelter with drinking water facility to be provided near the place of work failing which the Manager shall do the same.

8 Safety Appliances

Manager shall ensure that all contractors’ workers are provided with helmet, shoes & other safety gadgets. In case of non-provision, the safety gadgets shall be provided by him and the amount spent on the gadgets deducted from the contractors bill. Contractors shall ensure the use of helmets and shoes by his workers.

9 Fitness Certificate and road worthless

(i) Before the start of transportation, the contractor shall submit a list of vehicle/machines to be deployed at the mine to

of vehicle. the Manager/Project Officer(Agent)(ii) Fitness of all the vehicle/machines including AVA shall be checked under the supervision of Colliery Engineer.(iii) Fitness Certificate of all vehicles shall be checked by the Colliery Engineer and proper records shall be maintained. (iv) After the checking of the vehicle and fitness certificates, the Engineer shall recommend for the issue of valid pass for vehicle/machines to the Manager/Project Officer(Agent)(v) No’ contractors’ vehicle/ machines shall be allowed inside mine premises without valid pass issued by Manager/Project Officer (Agent) of the Colliery.(vi) A qualified engineer to have overall responsibility for daily/weekly checking and maintenance of contractors’ vehicle. Contractors shall authorize his engineer /foreman or mechanic as competent person for daily/ weekly checking and maintenance of vehicle/machines. Manager/Colliery engineer shall confirm the competency of such authorized person and ensure that the daily / weekly checking of vehicles is as per standards.(vii)Random check shall be made by Engineer/Safety Officer as regards fitness certificates, brakes, lights, horns, AVA’S etc.(viii) If any vehicle is found defective, the same shall not be allowed inside the mine, unless the defect has been rectified and vehicle certified to be fit by the Colliery Engineer in writing.(ix) The time of incoming and outgoing of contractors vehicles in the command area should be recorded in a register at the check post.

10 Unauthorized, driving / riding

(i) Contractors shall submit the list of drivers (whose antecedents he believes are good) along-with their valid licenses for verification and record by Engineer and issue of authorization by Manager/PO(Agent). No such drivers should be allowed without verification of license/authorization. (ii) No helper/ any-unauthorized persons shall be allowed to travel in dumpers. Trained trip man/helpers shall be provided at the loading and unloading point and for the miscellaneous jobs at key positions. Unauthorized riding in

vehicles shall make both the driver and /or the unauthorized person traveling liable to punishment.(iii) Manager shall take all appropriate steps including his authority of punishment to ensure prohibition of un-authorized driving as well as unauthorized riding.

11 Loading areas , Face supervisors : Under Manager / Overman / Mining Sirdar.

They shall ensure that:-(i) No unauthorized persons shall be allowed in loading/-waiting zone while loading and transportation are being carried on at the face.(ii) Safe distance shall be determined and maintained between shovels and dumpers.

12 Roads/Transport (i) A parking area for contractors vehicles/ machines shall be fixed by Colliery Engineer in consultation with PO/Agent of the mine.(ii) The number of vehicles allowed to enter the mine premises at a time should be fixed by PO(Agent)/Manager of Mine.(iii) The rest shelter for drivers/operators should be made outside the barrier.(iv) Manager shall ensure that all provisions of the condition of the use of HEMM issued by DGMS are complied .(v) One way traffic should be adopted for movement of vehicles. However, in extreme case whenever it is not possible to make one way traffic, alternative may be used only after approval of Agent of the Mine.(vi) Ramps and curved sections of the haul roads shall have adequate curvature and super elevation designed in accordance with the speed and height of vehicle plying on them.(vii) Escape lane or escape road shall be provided where there are chances of over speeding or roll back of vehicles in motion.(viii) Code of Traffic Rules, dumping practices, signaling and communication shall be framed and implemented.

13 Dumping Place (i) Sufficient dumping place shall be ensured by the Manager to avoid over crowding.(ii) Sufficient level space shall be provided on ramps close to unloading point for unloading, reversing and authorized parking.(iii) Dumping and manual loading shall not be allowed at the same place.

14 Parking i) No vehicle shall be parked on slope/gradient. If it is unavoidable, hand brakes shall be applied firmly, engine

stopped, vehicle kept in gear and stop blocks against the wheels used.ii) The engineer shall ensure that adequate numbers of stop blocks are always kept in the vehicle. In addition, he will also ensure that tow start vehicles are not allowed on the road.iii) Adequate level parking place should be created near loading point, CHP/Feeder Breaker/ Weigh Bridge, dumping place etc for incoming dumpers.

15 Surface Electrical Jobs

i)Jobs shall be done under the supervision of Engineer/Supervisors.ii) The Engineer/Supervisors shall ensure that proper shut down procedures for working on live lines are followed.iii) Code of Safe Practices shall be framed by Colliery Engineer for implementation on such jobs.

16 Explosive Management

Transport, storage, handling, usage etc of explosives and accessories shall be ensured by competent persons as per statutory provision.

17 Contractors responsibilities

i)Preparing written safe operating procedure for the work to be carried out, including risk assessment and safe method to deal with the risk and providing a copy of SOP to the person designated by mine owner who shall be supervising the contractor’s work.

ii) Keeping the SOP up-to-date and providing a copy of changes to the designated person.

iii) Ensuring that all work is carried out in accordance with the statue and SOP and deploy adequate qualified and competent persons for the jobs.

iv)Developing and providing site-specific code of practice for specified work to mine owner.

v) Every person employed by contractors shall wear safety gadgets either provided by contractor or by mine managementvi)Contractors shall submit quarterly or

monthly return indicating details of contracts, persons engaged, training and medical facilities provided etc to DGMS for contracts more than one year or less than one year respectively.

Q2. And old (about 30m high) overburden dump situated within 5m. of the quarry edge slide with a portion of the top bench ( in soft alluvium) and the second bench ( in unconsolidated strata) to the bottom bench burying three blasting helper deployed for charging holes.Write a report of enquiry assuming your own conditions.

Ans:- Enquiry Report

Ref.No……………………… Date………...

To,The Manager,“ X “ OCP.

Sub:- Enquiry report in respect of fatal accident involving 3 blasting helpers in X-open cast working due to

sliding of OB dump situated within 5m. of quarry edge.

Dear Sir,

As desired vide your letter no………………… dt…………… I am enclosing herewith the detailed enquiry report in respect of fatal accident in X-O/C working due to sliding of OB dump situated within 5m. of quarry edge indicating the cause and circumstances attending to the accident, contraventions of statutory provisions, responsibilities and suggestions to prevent similar accident in future as an annex.l . I am also enclosing the accident plan showing the site of accident along-with photo graphs.

Yours faithfully,Encl: As above.

( A.C.M. ) “X” OCP

Annexure - l

Detailed Enquiry Report

Assumption of Conditions:-The present X OCP is a part of Barakar formation having 3 coal seams namely Purewa top, Purewa bottom and Turra seam with an average stripping ratio about 1: 2.70(Coal: OB). The method of work is dragline-cum-shovel-dumper combination mining by using 4 nos. of dragline, 16 nos,. of shovel, 97 nos. of dumper and 18 nos. of drill of different make and capacities in two section namely eat and west section. I _______________, ACM, X OCP inspected the place, where this accident occurred and enquired into the cause and circumstances connected with the same.1)Introduction & information :- The accident occurred in X OCP of M/s……. on

……… at about 5.40A.M.. in 1st shift when an old OB dump situated within 5 m of the quarry edge slide with a persons top bench ( in soft alluvium) and the second bench ( in unconsolidated strata) to the bottom bench burying three blasting helper deployed for charging holes.. I received information about the accident at about 5.40 A.M.. when I was in my residence.

2)Background information:- The depillaring permission was obtained for extraction of coal by open cast method with dragline cum shovel dumper combination using deep hole blasting.

3) Occurrence of accident:- At about 5.40 A. M, a large volume of overburden (OB) dump measuring about 135m (length) & 6-19 x (height) x 70m (width) slide down from the failed dump and laterally shifted to the bottom bench burying 3 blasting helpers deployed for charging of holes. The coal rib about 15m thick left against the dragline dump collapsed, and approx.3 lakh cu.m loose debris of OB dump buried the 3 blasting helpers engaged on bottom bench.The huge quantity / volume of OB material slid down into the bottom bench. All the 3 persons, who had deployed for charging of holes were completely buried under the debris.

4) Rescue & Recovery:- The Disaster Management Plan was put into operation by the local management immediately. Three control rooms were set up at CGM Office, Coal section Time Office, and at the accident site. 3 nos of PC (bucket capacity – 2.8 cum), 5 nos. of Volvo Tipper, 6 nos. Higher Capacity Dozer were deployed by 12 A.M. The progress of different activities was monitored round the clock by top management. All the dead bodies were recovered after 72 hours.

5) Inspection & Enquiry: - On receiving information about the accident, I immediately inspected the place of accident along with the other supervisory staff and workmen. I made detailed observations and took some measurements at the place of accident and prepared a sketch of the place of accident giving leading dimensions. Photographs of the place of accidents were also taken. The sketch and photograph is attached with the report. I also examined witnesses and recorded their statements.

6)Analysis of evidence/ Observations: - From the inspection of place of accident, careful study of DGMS permission and analysis of evidence collected, the following were revealed:-

i) Wrong system of creation of dump bell was made.ii)Strong coal rib was left against the dragline spoil heap which ultimately failed

due to presence of water and clay at dump base.iii) Large volume / dead weight on consolidated dragline dump.

7)Cause of Accident:- The benches in spoiled OB dump failed because of their excessive height, insufficient width and presence of water & clay at dump base. The following are considered to be the technical reasons for the accident:-

i)The main technical reason for the collapse/slide is the gross deviation of the height & width configuration of benches at the place of accident w.r.t. stipulated conditions of DGMS.

ii). Coal rib left against dragline spoil heaps was not punctured immediately.iii) Lack of infrastructure for monitoring movement of dump slow.

8)Contraventions of statutory provisions:- Regulation 98 of CMR 1957 read with DGMS permission letter for extraction of coal by open cast method were contravened in respect of the following:-

i) Formation of benches/ Design of pit slope - The height, width and slope of benches were not maintained as per statute and conditions imposed by DGMS.

ii)Design of Dump Slope- OB Dump near the edge of quarry were made without taking into consideration the natural angle of repose of materials. As the height of the OB dump was more than 30m, its should have been properly benched with height not exceeding 30m and general slope not exceeding 1 in 1.5.

9)Responsibilities:- Enquiry into the accident revealed that if the workings were made properly benched and special care taken while working near the old OB dump as required under statute, the accident could have been averted.

The following persons are considered responsible for the accident:- i)General Manager/ deemed agent and agent- In contravention of provisions

of section 18(1) and 18(4) of Mines Act 1952 read with regulation 190 of CMR 1957, the General Manager/ deemed agent and agent of mine failed to effectively implement that all operations carried on in connection with the mine are conducted in accordance with the provision of mines act and regulation made their under.

ii)Manager- In contravention of provisions of reg. 98 and 41 of CMR 1957 read with sec. 18(4) of mines act 1952, the manager failed to effectively implement the conditions imposed by DGMS for formation of benches and design of OB dump.

iii) ACM- In contravention of provisions of reg. 98 and 42 of CMR 1957, the ACM failed to effectively implement the conditions imposed by DGMS for formation of benches and design of OB dump.

iv) Overman-In contravention of provisions of reg. 98 and 43 of CMR 1957, the Overman failed to effectively implement the conditions imposed by DGMS for formation of benches and design of OB dump.

10) Suggestions to prevent similar accident in future:- In my opinion, the following steps should be taken to avoid recurrence of

similar accidents in future: i) The conditions specified by the DGMS in relation to width and height of

benches should be strictly followed.ii) Coal rib should be of not more than 2m width at its top. To obviate

accumulation of large amount of water behind the coal rib, it should be

punctured intermittently. The analysis shows that even in absence of rib, the dump material is stable at the angle of repose.

iii) The coal seam floor, which forms the base of internal dump, may be ripped or blasted to a depth of 1 to 2m before start of dumping by dragline to improve the frictional resistance at the base of the dump. It will also facilitate the passage of water through the quarry floor down to the competent rock strata, thus, preventing accumulating of water at the base of the dump.

iv) An effective 10m bench width should be left along the roof of coal rib and a practice of leaving 10 m to 15 m bench width at dragline sitting levels should be followed.

v) The topsoil should be dumped separately. Under no circumstances such materials should be placed at the base of the dumps.

vi) Cut dumping by shovel-dumper should not be permitted in order to limit dragline dump height within permissible safe profile.

vii) The interface layer i.e. debris of coal dust, fragmented rock, soil mixed with water should be cleared as far as possible from the de-coaled floor before dumping by dragline. The analysis shows that the presence of the wet interface material decreases the factor of safety. If it cannot be avoided then it should be ripped by blasting.

viii) The valley in the dragline dump should be leveled to avoid rainwater ponding between the heaps of the dragline dump. The trapped rainwater between heap percolates to the lower levels of dump. The stability analysis shows that presence of rain water in the dump decreases its stability.

ix) The overburden excavated from the shovel-dumper benches should not be dumped on or near the freshly created dragline dump to avoid further loading of the partially consolidated dragline dump. Ideally, dumping of overburden excavated from shovel-dumper benches should be done at least two cuts away (160 to 180m).

x) The final resultant dump slope, after re-handling, should not exceed the angle of repose for the dump material (370).

xi) Slope monitoring is essential to detect any instability in advance to safe guard against possible slope failure.

xii) The dumps should be regularly surveyed to produce up-to-date and accurate dump geometry.

xiii) Geo-Technical cell shall be constituted in this regard at dragline mine with dedicated team equipped with sophisticated slope monitoring equipments like 3-D scanner / laser profiler/ target less total station / slope stability radar to monitor the dump slope stability.

xiv) Adequate infrastructure to be provided for imparting training on slope stability to all concerned person employed in the large open cast mine.

Q3. Write short notes on any four of the follow:e) Storage and transport of explosives.f) General requirement about the mine plan and sections.g) Apparatus under pressure.h) Place of accident.i) Appointment of officials and competent persons.

Ans:- a) Storage and transport of explosives- For extraction of mineral / ore, rock breakage using explosives is required. Safe

use of explosives needs strict control during its storage and transport. Specific statutory provisions have been made in statute in this regard which are enumerated below:Storage of Explosives- i) Explosives shall be stored in specially constructed building or structure known as magazine in accordance with the specification/ design provided in statute and approved by Chief Controller of Explosives i.e. duly licensed magazine. ii) The licensed magazine or storehouse shall be kept securely closed or locked at all times except when explosives are being placed in or taken from it.iii) The keys of the licensed magazine shall at all times be kept secured in licensee’s own custody or of his authorized agent and shall be produced for opening the magazine or store house whenever so required by an inspecting officer.iv) No owner, agent or manager shall store, or knowingly allow any other person to store, within the premises of a mine any explosives except in licensed magazine.v) Explosives shall not be taken into or kept in any building, except a magazine duly approved by the Licensing Authority.However, RIM may, by an order in writing and subject to such conditions as he may specify therein, permit the use of any store or premises specially constructed at or near the entrance to a mine, for the temporary storage of explosives intended for use in the mine or of surplus explosives brought out of the mine at the end of a shift.vi) Explosives shall not be stored belowground in a mine except with the approval in writing of the Chief Inspector and subject to such conditions as he may specify therein. Such storage shall be done only in a magazine or magazines duly licensed by licensing authority..vii) Every license granted by the Licensing Authority under the Indian Explosives Act, 1884 for the storage of ex-plosives or a true copy thereof, shall be kept at the office of the mine.viii) Every magazine shall in charge of a competent person who shall be responsible for the proper receipt, storage and issue of explosives and shall issue explosives only to authorized/competent persons upon written requisition signed by the blaster or by an official authorized for the purpose.

Transport of explosives- i) No person shall transport or cause to be transported any explosive in a road van or compressor mounted motor truck or tractor unless such vehicle is licensed under the statute. Only such drivers or cleaners, whose antecedents are verified by the local police, shall be engaged for driving of van etc.

ii) Every road van shall be provided with two fire extinguishers of minimum two kg. Capaicity (one for electrical fire and other for inflammable components). iii) No person shall transport or cause to be transported any explosives on any road within the limits of a municipality or cantonment where such a road is specifically prohibited for plying vehicles carrying explosives.iv) No other goods shall be carried with explosives in any vehiclev) While explosives in bulk are lowered or raised in a shaft or winze, a distinguishing mark shall be attached to the cage, skip or bucket containing the explosives or the person in charge of explosives shall travel in the same cage, skip or bucket.vi) Every cage, skip or bucket containing explosives shall be gently lowered or raised; and it shall be the duty of the banksman or bellman, as the case may be, to adequately warn the winding engineman before the cage, skip or bucket is set in motion.vii) Whether explosives are being carried on a ladder, every case or container shall be securely fastened to the person carrying it.viii) No person other than a blaster shall carry any priming cartridge into a shaft, which is in the course of being sunk. No such cartridge shall be so carried except in a thick felt bag or other container sufficient to protect it from shock.

Ans:- b) General requirement about the mine plan and sections- An accurate and reliable mine plan is required to be prepared and maintained upto date by surveyor for safe working of mine. The general requirement of a mine plan and section are listed below:1) Every plan or section shall –a) show the name of the mine, name of the owner and its purpose b) show the true north or the magnetic meridian with date.c) show a scale of the plan, at least 25 cm long and suitably sub-divided;d) be on a scale having a representative factor of-

i) 200 : 1 , in case of mica mines and other mines having small scale workings belowground:

ii) 2000 : 1 , in case of mines having large open cast workings and also in case of surface plans of large leasehold areas and

iii) 1000 : 1, in other cases;However, DGMS may permit or require the plans to be prepared on any other suitable scale: e) be properly linked in on durable paper or on tracing cloth and be kept in good condition.2) Only conventions shown in second schedule of MMR shall be used in preparing all plans and sections.3) The plans and sections shall be accurate within such limits of error as may be specified by DGMS.4) The plans and sections required under these regulations shall be maintained up-to-date within 3 months except in case of opencast workings in respect of which it shall suffice if the plans are maintained up-to-date within 12 months.

However, in case of abandoned/discontinued/inaccessible workings, the plan and section shall be brought up-to-date before such abandonment or at the time to discontinuance unless such abandonment or discontinuance has been caused by circumstances beyond the control of management in which case the fact that the plan/section is not up-to-date, shall be recorded on it.5) Plans and sections shall be kept available for inspection in the office of the mine and shall not be removed unless exempted by RIM. However, a true cop of the same shall be kept in the office of the mine before such removal.

6) A permanent benchmark shall be established on the surface and all levels taken above and belowground shall be referred to a plane in relation to such benchmark. Particulars of benchmark together its height above mean sea level shall be shown on the plan.7) Every plan and section shall carry a certificate of correctness on it and shall be signed and dated by the surveyor and countersigned and dated by manager on every occasion that the plan and section is brought upto date.

Ans:-c) Apparatus under pressure- There has been instances of accidents resulting from the use of substandard equipment, defective installation and unsatisfactory maintenance of apparatus under pressure. To avoid this, provisions have been made in the statute which are enumerated below:(1) All apparatus containing or producing air, gas or steam at a pressure greater than atmospheric pressure shall be so constructed, installed and maintained as to obviate any risk of fire, bursting, explosion or collapse or the production of noxious gases.(2) Every air receiver forming part of a compressing plant shall be fitted with a safety valve and an air gauge, which shows pressure in excess of the atmospheric pressure.(3) Before an air- receiver is cased in or put in commission, the engineer or other competent person shall subject it to a hydraulic test at a pressure at least 1½ times the maximum permissible working pressure. A similar test shall be made after every renewal or repair and in any case at intervals of not more than 3 years. The result of every such test shall be recorded in a bound paged book kept for the purpose, and shall be signed and dated by the person carrying out the test.However, in the interest of the safety it is recommended that whenever hydraulic test is done as requested under the law, assessment of safe working pressure shall also be done based on residual thickness, pitting and corrosions of the wall of such pressure vessels. The present thickness of wall, scam etc shall be compared with original thickness and a decision to repair/replace the receiver shall be taken. When it is not possible to measure the thickness of wall physically, ultrasonic thickness gauge should be used.(4) The supply of air for air-compressor shall be drawn from a source free from dust and fumes. In addition to above, the following additional precautions/safety measures should be strictly followed where high-pressure compressed air is used either above ground or below ground in mines:i) Air valve, pipes, bends and other fittings of the compressed air system should confirm to ISS and should have ISI marking.ii) The compressed air distribution system should be provided with suitable isolating valve at every branching off point.iii) Suitable water trap or drain cock should be provided before isolating valves and the accumulated water in the trap should be properly drained before opening the isolating valve.iv) Suitable pressure gauges should be provided on the outlet side of the isolating valves on the main air range on the surface as well as underground to ensure proper functioning of the valve.v) The hosepipe conveying high-pressure air should be of reliable make, robust, of tested quality and antistatic type.

Ans:- d) Place of accident:-

During investigation of any mining accident, the site / place of accident gives vital information. Hence, the site/place of accident in a mine should not be disturbed / altered in any way unless situation demands so. In this regard reg.190 of MMR’1961 stipulates the detailed provisions, which are given below: i) In case of fatal or serious accident in a mine, the place of accident shall not be disturbed or altered before the arrival or without the consent of DGMS officials unless such disturbance or alteration is necessary to prevent any further accident, to remove bodies of the deceased or to rescue any person from danger, or unless discontinuance of work at the place of accident would seriously impede the working of the mine. However, if DGMS officials fail to inspect the place of accident within 72 hours of the time of the accident, work may be resumed at the place of accident.ii) Before the place of accident involving a fatal or serious accidents is disturbed or altered due to any reason whatsoever, a sketch of the site illustrating the accident and all relevant details shall be prepared (in duplicate) and such sketch shall be duly signed by the manager or assistant manager, safety officer, surveyor and the workmen’s inspector or, where there is no workmen’s inspector, by a work person nominated by the workers in this behalf.When the place is disturbed or altered to prevent further accident or rescue persons from danger before the sketch could be prepared, the same shall be prepared, immediately thereafter giving all relevant details as existed before the place was disturbed or altered.iii) One of the authenticated sketches shall be delivered or sent to the concerned Inspector of mines.

Ans:- e) Appointment of officers and competent persons:- Refer to Q.No.6(a) – 1st

class 2009.

Q4. a) What are the new diseases proposed to be included in the list of Notified diseases. What changes do your suggest in the Occupational Health Surveillance system to comply with the recommendations of the 10th Safety Conference.

b) What facilities shall be provided to the Inspector for Occupational Health Survey?

Ans:- a) Notified diseases:-These are those diseases which have been notified by the central Government in the official Gazette as diseases connected with mining operations. These includes Silicosis Coal miner’s pneumoconiosis Manganese – poising nervous type Asbestosis Pneumoconiosis Cancer of lung or the stomach or the pleura and peritoneum.Under factory Act, Noise induced hearing loss has been notified by Central government as notified disease.Under section 25 of mines act 1952, it has been specified that where any person employed in a mine contracts any notified disease, mine management shall send notice to CIM, DM, RIM, Inspector of Mines (Medical) within three days. In addition to the existing notified disease, the following new occupational diseases should be included in the list of notified diseases:-i. Siderosis and Berillyosis.ii. Noise induced hearing loss

iii. Carbon monoxide poisoningiv. Contact dermatitis caused by contact with chemicals.v. Pathological manifestations due to radium or radioactive substances.Suggestion for changes in the occupational health surveillance system to comply with the recommendation of the 10th Safety Conference:-In view of the current hazard pattern and status of occupational health surveillance in the mines, the following changes should be made in the present system in order to comply with recommendation of the 10th Safety Conference:1) Setting up structured occupational health services with adequate trained manpower and facilities, which should have a built in mechanism to monitor occupational health surveillance programme in addition to other occupational health activities of the entire organization. 2) Regular short-term training programmes on occupational health and hygiene with special reference to dust and noise monitoring and diagnosis of occupational diseases and use of ILO classification need to be organized. 3) Identification and assessment of health hazards in workplace.4) Control of working environment by elimination or minimization of occupational health hazards5) Establishment of effective First-Aid machinery.6) Establishment of necessary arrangement for subsequent Medical emergency.7) Proper maintenance of Health records and relevant statistics.8) Putting in place an effective policy for rehabilitation of sick and injured person.9) Development of Health promotional activities including Health education.

. 10) Noise mapping of various work places in the mine premises based on the various machines being used in concerned mines along with personal noise dosimetry of individual workmen exposed to noise level above 85 dbA.11) Vibration studies of various mining machinery including drills, SDLs, LHDs, excavators, motor graders, dumpers, etc.12) Ergonomic assessment of all latest machines, before their introduction into mining operation. Ergonomical assessment should include: Assessment of work process Assessment of working aids/tools Assessment of working posture13) Potability test of drinking water supplied to the mine employees, to be made mandatory once in a year irrespective of its source, the sample of water to be collected from the points of consumption.14) IME should be made mandatory for all mining employees whether permanent, temporary or contractual, before they are engaged in any mining job. 15) The frequency of PME should be brought down from existing 5 yrs to 2 yrs for the mining employees above 45 yrs of age.16) Each mechanized mine should engage at least one qualified medical officer for every 500 employees and thereafter, one for every 1000 employees.17) One of the medical examinations of every person should be arranged within one year of his superannuation.(18) Standards IME & PME shall be suitably modified in order to ensure early diagnosis of diseases caused due to employment in mines.(19) Special tests should be included in the PME for employees exposed to specific health hazard.(20) Each PME center should have its own facilities of Pulmonary function test and ILO classification of Chest X-rays. Every chest radiographs of medical

examination should be classified by PME Medical Officer and he should be trained in use of ILO’s classification.(21) Every mining organization shall computerize all the environmental surveillance records along with computerization of total health records of all mining employees. The mining companies shall draw exposure profile of individual employees for all types of hazards to which they are exposed to at their work places.Ans:-b) Facilities to be provided by mine management for Occupational Health Survey: i) Section 9A of Mines act 1952 empowers DGMS to undertake safety and occupational health survey in a mine at any time after giving notice in writing to the manager of the mine. Mine management shall afford all necessary facilities for this purpose.ii) Every person chosen for occupational health survey shall present himself for examination and furnish all information regarding his work and health in connection with the said survey.iii) The time spent by any person chosen for examination in such survey shall be counted towards his working time. So however that any overtime shall be paid at the ordinary rate of wages.

iv) If such person is found medically unfit on such survey, he shall be entitled to medical treatment at the cost of the owner, agent or manager with full wages during the period of such treatment.

v) If after such treatment he is declared unfit to discharge the duty which he has discharging and such unfitness is directly ascribable to his employment, he is entitled for an alternative employment in the mine for which he is medically fit or for payment of disability allowance at the rate of 50% of monthly wages that he was receiving before such survey.

Provided that where such persons decide to leave his employment in the mine, he shall be paid a lump sum amount by the way of disability compensation.

Q5. The number of accidents in mechanized opencast mine during transportation of ore and also in the ore beneficiation plants are increasing. State the probable reasons for increase in accident and enumerate the preventive measures to be adopted for the same.

Ans:- Increased demand of mineral has necessitated large amount of mineral / waste handling in the mines. The O/C activities have thus been under immense pressure to boost production and achieve required target. However, increase in O/C mining activities in large mechanized O/C mine has unfortunately been associated with increased number of accidents.The most common mode of transport of ore and minerals in O/C mines is dumpers & trucks and its use is on the increase.During the last few year fatal accidents have shown an increasing trend in mechanized o/c mine during transportation of ore and also in the ore beneficiation plants. Accidents due to transportation machinery in mechanized o/c mines continue to remain high. .Enumerated below are probable reasons for increase in accident in mechanized open cast mine during transportation of ore and also in the ore beneficiation plants vis-a-vis the preventive measures:

Probable reasons Preventive measuresi) Running over of high capacity dumpers over light motor vehicles on haul roads.

Providing & maintaining a separate road in the mine premises for the light motor vehicle used for inspection and

transportation. This road should not cross the haul road at any place in the mine premises.

ii) Fire in HEMM due to short circuiting or otherwise.

Using approved type fire fighting and fire suppression systems including automatic fire detection & suppression system in HEMM.

iii) Non-functioning & non-provision of audio-visual-alarms in dumpers & tippers resulting in run over of vehicle during reversing.

No dumper and tipper should be allowed to be in use without providing reliable type of AVA’s to be actuated automatically during reversing. Also spotter should be deployed.

iv) Ill maintenance of contractors/hired machinery resulting into accident.

All contractual/hired machinery should be audited/inspected by a team consisting of mine officials and contractor technical personnel for their suitability. Checking of contractor equipments by departmental competent person.

v) Rolling back of dumpers and felling down on the lower bench due to sudden stop of engine of dumper owing to non/partial functioning of brake and non-functioning of the emergency steering system resulting into backward movement of dumper.

Maintaining parking brake/service brake and secondary braking system & emergency steering unit in dumpers in safe working order.

vi) Rolling down of tippers /dumpers due to failure of service brake while plying on gradient.

Regular checking of braking system including parking brakes and maintaining the same in safe working order.

vii) Sudden breakage of propeller shaft of dumpers / tippers damaging the service brake and subsequently rolling down of the same.

Ensuring provision of sturdy safety guard for the propeller shaft.

viii) Use of survey off equipment. Thorough checking and inspection of equipments by a tripartite committee consisting of representatives from OEM, mine management and independent agency before putting the survey of equipment in use and ensuring assessment of structural stability at least once in 6months during the extended use.

ix) Head on collision / front to rear collision of dumpers on haul road due to poor visibility, skidding or falling from the bench.

All roads shall be maintained in good condition. As far as practicable there should be one-way traffic. If this is not possible, roads should have 3 time plus 5m the width of the largest vehicle. Corners and turnout should be such that the operator has a clear view

up-to 3 times the braking distance of largest vehicle plying in the mine. No road should have a gradient steeper then 1 and 16. Where road exists above the surrounding area, parapet wall of diameter of tyre of largest vehicle plying in the mine. No unauthorized person should travel on the dumper. The roadway should be provided with light having minimum intensity of 0.5 to 3.0 lux. Blind spot mirror apart from rear view mirror to enable operator to have clear visibility of blind spot in front and sides of dumpers. Anti collision device to avoid head to tail collision on haul road such as tailgate, bumper extension or any other strong device. Seat belt for operator.

x) Failure of brake. The parking brake and the service brake shall be maintained in safe working order. Periodically the brake should be tested.

xi) Failure of steering. All joints, locks, lever etc shall be examined and kept in safe working order.

xii) Bursting of tyres in operation. Tyres should be examined for any defect and it should have right inflating pressure.

xiii) Not following traffic rules and code of practice for movement of vehicles.

The code of practice for installation operation and maintenance of all equipment shall be prepared and implemented before putting the equipment to use in mine.

xiv) Unskilled, negligent and unauthorized driving / riding of trucks.

No helper/any – unauthorized person shall be allowed to travel in dumpers/ tipping trucks. Trained trip man/helpers shall be provided at the loading and unloading point and for the miscellaneous jobs at key positions. Unauthorized riding in vehicles shall make both the driver and/or the unauthorized person traveling liable to punishment.

xv) Uncontrolled fleeting and over crowding of vehicles.

Sufficient dumping place shall be ensured by the Manager to avoid over crowding.Sufficient level space shall be provided on ramps close to unloading point for unloading, reversing and authorized parking. Dumping and manual loading shall not be allowed at

the same place. No vehicle shall be parked along slope/gradient. If, it is unavoidable, hand brakes shall be applied firmly, engine stopped, the vehicle kept in gear and stop blocks against the wheels used. Adequate level parking place should be created near loading / unloading points.

xvi) Collapse of bunker structure in ore beneficiation plants.

Steel used for fabricating the structure should be free from defects and foundation of all pillars should be shrouded with cement concrete to avoid corrosion and pitting. A system of annual inspection of beneficiation plants using visual & NDT techniques should be made. The structural stability of ore beneficiation plants shall be carried out periodically by an independent agency.

xvii) Fall of persons while working at height in ore beneficiation plants.

A working platform/stage or scaffold of adequate width with proper fencing shall be provided. A safe means to access to the working platform shall be provided.Only approved type of safety belt or life line conforming to Indian Standard IS:3520-1999 shall be used which shall be properly maintained and checked for its fitness before every use.A code of safe procedure shall be prepared and implemented for such type of dangerous jobs which amongst others may include training of persons, supervision before engaging contra ctual persons etc.

xviii) Injury to persons being drawn into conveyor drums and pulleys.

Proper guards & fences should be provided.Over and under bridges at crossings should be provided.Pull chord system should be provided to stop the conveyor from any point all along its length.

xix) Accident due to fire in belt conveyors arising from slipping of belt on the drum, rubbing of the sides of the gear head, over heating, friction etc.

Installation of belt protection switches at the points potential sources of heat / fire. Similar devices can be made to operate water sprays in case of excessive heat.

Q6. In view of recent terrorist activities around mining areas what change do you suggest in procurement, storage and safe use of explosives. What other methods do you suggest for winning minerals avoiding traditional blasting system. Explain brief.

Ans:- In recent past, terrorist activities around mining areas has increased. Terrorists are often using explosives and accessories for land mine blast resulting into heavy casualties as well as fear among the innocent people. It has also been noted that the transportation of explosives often without proper security cover in C.P.I. ( Maoist.) infested states like Jharkhand, Chhatisgarh, Orissa, Andhra Pradesh, Maharastra, W.Bengal, Bihar have become cause of concern to the security agencies. In many places, the mines and explosives magazines which are being operated either by the PSU’s or by corporate companies in coal, steel, aluminium, atomic sectors lack adequate security cover in terms of deployment of trained security personnel, sufficient sophisticated arms and ammunitions so as to withstand the onslaught of the terrorist. In view of the above facts, the following changes in the system of procurement, storage and safe use of explosives may be made in my opinion:i) For procurement of explosives, NIT should be invited from reputed & bona fide manufacturers /suppliers of explosives having valid license for manufacturing and storage of explosives. Manufacturers must comply with all statutory conditions imposed by licensing authority in respect of safe manufacture, packing, storage and transport of explosives. ii) The licensee shall provide security guards for safe custody of the factory or magazine for storage of explosives. If possible, all explosive vans should be equipped with GPS tracking system.iii) Explosives shall be transported from factory to magazines / mines in approved and licensed road vans driven by authorized person.iv) Procedure to be followed during transportation of explosives from factory to magazines / mines:

a) Every consignment of explosives transported under licensee shall be accompanied by a pass issued by the consignor in Form RE-12.b) Such pass shall be attached to the way bill, invoice or dispatch note.c) A copy of every pass shall forthwith be sent by the consignor to -

the licensing authority who issued the license of the consignor; the controller and the District Superintendent of Police in whose

jurisdiction the place from which the consignment is sent is situated;

the controller and the District Superintendent of Police in whose jurisdiction the place to which the consignment is sent is situated.

v) Every explosives magazine licensee shall inform the nearest police station in whose jurisdiction the place from which the consignment is sent is situated and to the nearest police station in whose jurisdiction the place to which the consignment is sent is situated at least 24 hours in advance and dated acknowledgement may be obtained.vi) Every licensee shall obtain acknowledgment for submission of the Pass RE12 to the concerned District Superintendent of Police as obligatory under Explosive Rules and carry a copy of such acknowledgement in the Van carrying Explosives.vii) A road van while transporting explosives shall always be attended to by two armed guards at the expense of the licensee. If the consignment of explosives is likely to pass through sensitive areas notified by the Ministry of Home Affairs, it

should be escorted by armed police escort or guard, provided by the District Police Administration.viii) The operator of a vehicle used for transport of explosives shall ensure that the driver or any attendant thereof has in his possession the following documents during transport namely:

a) Copy of indent in Form RE-11 b) Copy of transport pass in Form RE-12c) Copy of road van licensed) Original copy of bill of explosives being transported.

Which shall be produced on demand by Chief Controller / Controller of explosives, District Magistrate, Superintendent of Police and DGMS..ix) All licenses shall bear the photograph of the licensee or occupierx) For purchase & transaction of explosives, following procedures shall be observed:

a) Indent Form RE-11 shall be signed by the licensee or his authorized representative.b) Photograph and specimen signature of the licensee or occupier shall be filed with the supplier of explosives.c) Photograph, specimen signature and address of the licensee’s authorized representative duly attested by the licensee or occupier shall be filed with the supplier of explosives.d) The supplier of explosives shall verify the photograph and signature before effecting the delivery.e) The authorized representative shall represent one licensee only for receiving explosives on his behalf.

xi) Control of pilferage of explosives: a) Explosives shall be transported from magazine to mines and vice versa through licensed road van under security cover.b) Only such persons should be appointed as magazine in charge, shot firers and explosive carriers, who have been found to be entirely trustworthy.c) The number of shot firers and explosive carriers should be kept to a minimum.d) Senior Officials should frequently have surprise checks on the amount of explosives with carriers and shot firers at different times during the shift..e) A list of shot firers in service on 1st January every year with the details such as name, father’s name, residential address, home address & number and kind of certificate held for shot firing shall be prepared and send to Superintendent of Police for checking the antecedents of shot firers and keeping a watch on them.f) A scheme for prevention of pilferage of explosives shall be prepared and implemented by the mine management taking into account the following: Selection of shot firers / blasters & Explosive carriers based on Police

verification. Cases or canisters of Explosives with adequate safety provisions. Issue of transit slips for transport of explosives. Various checks in magazine, at pit top, in u/g, return of unused

explosives, stock checking in magazines etc.g) The licensee or a shot firer employed by him to be in-charge of blasting operations shall take all precautions against loss, pilferage etc. and will be

personally held responsible for any contravention of the statutory provisions.

Methods for winning minerals avoiding traditional blasting system:In recent times, more and more emphasis is being placed on the negative effects of blasting in the extraction industries. In addition, the legislative control of the use of explosives is becoming more vigorous, making their use more difficult in mines where blasting requirements are deemed to cause nuisance.

The growth of urbanization along-with increased human sensitivity to blasting operations especially in close proximity of mining and quarrying areas, safer excavation by non-explosive methods is sometimes more important than traditional blasting system.

The following are the methods for wining minerals avoiding traditional blasting system:

i) Use of “Acconex”:. It is non-explosive silent demolition compound different from conventional materials/system like explosives/hydraulic splitter. It does not cause any noise, flying debris, toxic fumes, vibration or any environmental pollution.

It functions by exerting expansive forces/ stress generated when the material is poured in the drilled holes in slurry form. The expansive stress reaches a level more than 6000 t/m2 . Normally the compressive stress of rock is in the rang of 1000 to 2500 t/m2 in concrete. The tensile fracture stress is very small which ranges from 40 to 50 kg/cm2 in concrete. Since demolition with Acconex is based on fractures due to tensile stress, all kinds of rock and concrete can be demolished by initiating cracks.Limitations: Continuous stirring is required while mixing water. Acconex slurry is to be used within 10 minutes of mixing. In case of rock cleavages or cracks, plastic sleeves are to be

used. Holes with acconex should be covered with gunny bags or

tarpaulins. Very careful operation is required to avoid any accident.ii) Capsuled compressed Gas cartridges:Two general types of non-explosive compressed gas systems have been developed in the U.K. and USA, primarily for ‘soft ground’ applications.To enhance safety, these are used in underground coal mining for loosening compacted bulk materials in storages and for dislodging accretions from hot furnaces. The impact depends upon the build – up of gas pressure in a cylinder, which, following a trigger action, is suddenly expanded into the material to be broken or loosened. In case of coal mining, the cylinders are located in regular boreholes.iii) Mechanical methods:Tungsten carbide tipped steel (rotating & traversing) abrading elements are now used to excavate rock of soft to medium hardness.Specialized ‘ continuous miners’. Tunneling moles, road- headers, and large diameter shaft/raise borers have been developed recently to employ these principles in soft to medium rock without the use of explosive.

Secondary breaking of large hard rock boulders by thermo-mechanical methods has recently been developed, wherein, the rock is first heated and then fragmented by mechanical impact.iv) Electrical Methods:Various methods of breaking rock by electrical energy have been investigated, including heating by induction, high frequency, microwave, electron beam, plasma jet, arc, and condenser discharge techniques.The electro thermal loosening (ETL) technique involves the normal drilling of blast holes followed by a pair of electrodes (using AC at normal frequency) in adjacent holes, then a breakdown voltage (K.V0.4 to 10.) is applied as a succession of vigorous electro thermal jolts, at the pre-blasting stage.v) Liquid jet system:Panoply of high-pressure jets, both continuous and discontinuous systems, with or without abrasive materials have found interesting applications worldwide. Pulsed water jets at pressure of 6896 kg/cm2 can fracture rock and concrete. By incorporating a battery of high-pressure water jets on a tunneling machine, it is conceivable that conventional tunneling practices may be revolutionized.vi) Expansive Mortar :Expansive mortar can fracture rock and concrete with force expansive in excess of 1034 Kg / cm2 The system eliminates problems caused by blasting and increases productivity of mechanical breakers. It can also be used for pre-splitting rock in sensitive conditions and has the capability to function properly even in larger hole diameters both in dry and watery condition.vii) Surface Miner: Surface miner can be used for cutting coal and soft to medium-hard rock (<90 Mpa ) with mechanically driven cutting drum and two-part loading conveyor. Surface miners are suitable for mining in fairly flat deposits, geologically undisturbed think seams and thick seams having dirt bands of varying thickness.viii) Plasma Blasting:Electrical plasma blasting technology is basically an electrical technique in which electrical energy transforms an electrolyte solution in a borehole into a high pressure high temperature plasma. The plasma transformed from the electrolyte solution in a borehole reached an energy of 280 kj by electrical input of 8.5 KV and 200A and this rapidly released energy in the borehole developed a shock wave, which in turn produced a stress field that fractured the rock without producing excessive dust and fly rocks. The range of plasma strength varied with chemical additives.In Plasma Acoustic Blaster (PAB) mechanism, a hole (or holes) is drilled into an object to be blasted and water is filled in it. Energy is discharged in it hereby generating a shock wave for breaking the rock. Compared with conventional blasting method, the PAB technology, which uses no chemical substances, is eco-friendly, because it causes less vibration, noise and dust. In PAB, a reusable blasting electrode and a power supply main body, incorporating capacitors and other devices that are connected by a cable are used.However, there has not been any established method that can replace the vast usage of commercial explosives for exploitation of coal and minerals.

Q7. Write short notes on –d) Working and examination of machinery.e) Plans & sections to be submitted after abandonment or discontinuance.

f) Appointment of engineers.g) Emergency plan.

Ans:- a) Working and examination of machinery-To avoid accidents due to machinery in mines, machinery shall be maintained in safe working order and operated safely. For this purpose, machine maintenance schedule should be prepared and strictly implemented. However, reg. 76 of MMR’1961, makes the following provisions in this regard:i) No machinery shall be operated otherwise than by or under the constant supervision of a competent person.ii) In every gassy mines, no person shall be appointed to supervise or operate any electrical machinery, apparatus or appliance other than a telephone or a signaling device or an electric lamp or light, unless he holds a gas testing certificate.iii) Every person in charge of any machinery, apparatus or appliance shall, before commencing work, see that it is in proper working order and if he observes any defect therein, he shall immediately report the fact to the manager, engineer or other competent person.iv) Every person in charge of air- receiver shall see that no extra weight is added to the safety valves and that the permissible pressure of air is not exceeded.v) A competent person or persons appointed for the purpose shall, once at least in every seven days, make a thorough inspection of all machinery and plant in use and shall record the result thereof in a bound paged book kept for the purpose.

Ans:- b)Plans & sections to be submitted after abandonment or discontinuance:- i) Where any mine or in case of a gassy mine is abandoned or the working thereof has been discontinued over a period exceeding 4 months, the person who was the owner of the mine at the time of the abandonment or discontinuance shall, within 30 days after the abandonment or within 5 months after the discontinuance of the workings, submit to the Chief Inspector two true copies each of the up-to-date ug plan and section, traverse section (s) of the workings through the shafts and main edits etc & vertical mine section. Every such copy shall show the bearing and distance of a least one of the shafts or openings of the mine from a tri-junction or revenue pillar or from any other prominent and permanent surface feature, the position of all water-dams built belowground (with their dimensions and other particulars of construction) and also the spot levels at the ends of the workings.When the change of ownership occurs after the abandonment of discontinuance and before the expiry of the 30 days or five months aforesaid, as the case may be, such plans and sections shall be submitted forthwith.ii) The original or a certified true copy of the plan and section submitted as mentioned above shall be kept in the office at the mine.iii) The Chief Inspector may, on such conditions as he thinks fit to impose and on payment of the cost of preparing copies as determined by him, supply copies of a plan or section already submitted or such parts thereof as he thinks fit-

a) to any person having a bona-fide interest in the mine or part or b) to the owner, agent or manager of an adjacent mine.

Requirement of AMP- The AMP should be submitted on tracing cloth or polyester tracing film with index number of the original plan from which it is traced. It should be certified to be a true copy of the original plan by the

surveyor and countersigned by the manager. The AMP shall show the detailed information as required under statute as follows:i) Name of owner, mine, plan, true north or magnetic meridian with date of the latter, a suitable scale, conventions as per the second schedule.ii) Up-to-date position of workings belowground, ends of workings to be marked with dotted lines and last date of survey.iii) Position of every fault, dyke and other geological disturbances with amount of throw and direction.iv) Vertical mine sections (if inclination exceeds 30º)v) Every important surface feature within the boundaries such as railway, road, river, stream, watercourse, tank / reservoir, opencast working, village (with name) and building which is within 200m of any part of the working measured horizontally. HFL of river/stream.vii) Spot levels at the end of all workings.vii) Mine boundary.viii) An abstract of all statutory restrictions in respect of the workings (with DGMS letter number)ix) If the plan has not been updated up to the time of abandonment, this fact should be recorded on the plan. If barriers with adjacent mines are not adequate, this fact should be recorded on the plan and, where necessary management of the adjacent mines should be warned. If any workings lie beneath railway, public road and building not belonging to the owner, and are inaccessible, the fact should be recorded on the plan.x) Position of all pumps and lodgments underground together with information concerning the quantity of water being pumped out before abandonment. Also position and extent of known water logging.xi) A certificate of correctness of the plan (as printed in the original plan.)

Ans:-c) Appointment of engineers- For installation, operation and maintenance of plant and machinery, competent supervision is essential which is ensured by appointment of engineers or competent persons. Reg. 36 of MMR’1961, stipulates detailed provision for appointment of engineers which are given below:i) At every mine where machinery is used, an engineer or other competent person not less than 23 years of age shall be appointed to hold general charge of such machinery, and to be responsible for its installation, maintenance and safe working.Two or more engineers or competent persons at one mine may be appointed so long as the jurisdiction and sphere of responsibility of every such engineer or competent person is defined by the manager in his letter of appointment.No person (unless he holds a degree or diploma in mechanical engineering or equivalent qualification approved for the purpose by the Central Government) shall except with the previous permission in writing of the Chief Inspector and subject to such conditions as he may specify therein, be so appointed in an opencast mine worked by HEMM in which the aggregate h.p. of all the machinery used exceeds 750, or in any other mine in which the aggregate h.p. of all the machinery used exceeds 250. ii) A notice of appointment of engineers giving the name and full particulars of the qualifications and experience of the person so appointed, shall be sent to the Regina Inspector within 7 days of such appointment.iii) No person shall undertake the duties of an engineer at more than one mine without the previous permission in writing of the Regional Inspector. The regional inspector may at any time, by an order in writing, vary or revoke such permission.

iv) Where by reason of temporary absence or for any other reason, the engineer or competent person is unable to perform his duties, the manager shall authorize in writing a person whom he considers competent to act in his place:

Provided that- (i) notice of every authorization shall be sent to the Regional Inspector forthwith.(ii) no such authorization shall have effect for a period in excess of 30 days except with the previous consent in writing of the Regional Inspector and subject to such conditions as he may specify therein; and (iii) the Regional Inspector may, by an order in writing revoke any authority so granted.

Ans:-d) Emergency plan- An emergency plan is a programme of action to be followed in emergency. It should clearly indicate the duties and responsibilities of each mine official and some other key persons like telephone operator, attendance clerk, cap lamp in-charge etc. This plan should be drawn up taking into consideration special features of mines, foreseeing every possible source of dangers and damages. It consists of programmes, which provide for prior arrangements to be kept in readiness before emergency strikes and also operative part of the emergency plan to deal with the emergency as and when it strikes.Necessity of Emergency Plan: - An emergency plan is required to be kept prepared specially for the following reasons:- i) To avoid chaotic condition which develops after an emergency /

disaster. ii) To keep the persons trained before hand with details as to what to do and

what not to do, whenever an emergency arises.iii) To save human lives who might get isolated due to emergency.To save the mine by taking action to deal with the emergency as early as possible Statutory Provision: - As per regulation 190A of MMR 1961, the following are the statutory provisions for framing and enforcement of emergency plan:1. The manager of every belowground mine shall prepare an emergency plan outlining the duties and responsibilities of each mine officials and keymen including the telephone operators who shall be thoroughly instructed in their duties so as to avoid contradictory orders and confusion at the time when prompt and efficient action is required.2. The emergency plan shall also provide for mock rehearsals at regular intervals. 3. The Manager shall submit a copy of emergency plan within 30 days of opening of mines to RIM, get it approved and enforce at the mine. 4. When any emergency occurs, manager /principal official shall immediately put the emergency plan into operation. This Plan should be updated from time to time.

Essential elements of a good emergency plan- Following are the salient points to be kept in mind while drawing an emergency plan:1. The first few hours immediately after any emergency are of vital importance. 2. Each member of the organization should be given duties with which he is

generally familiar, so that he does not have to learn a new to play. 3. At the time of the actual occurrence, the Manager has to use his discretion in

adopting the plan according to the nature and scale of the emergency.

4. The officials in the pit at the time of the occurrence have to act according to their own knowledge and initiative

5. Every person involved in the operations must clearly understand, in advance, his particular role.

6. The possible causes and magnitude of emergency should be envisaged,The manager has to keep in mind the nature of expected emergency while drawing up the emergency plan. Various components of the plan would however, be the same irrespective of the nature of emergency.

Afternoon Session THE MINES ACT, 1952

EXAMINATION FOR MINE MANAGER’S CERTIFICATE OF COMPETENCY(UN-RESTRICTED ) UNDER THE METALLIFEROUS MINES REGULATIONS,1961

FIRST CLASS

MINE MANAGEMENT, LEGISLATION & GENERAL SAFETY (UN-RESTRICTED)

SUNDAY, THE 4th OCTOBER, 2009 Full Marks: 100 Time : 3 Hours

First question carries 20 marks and is compulsory.Answer any five other questions which carry equal marks

……………………..Q1. Write notes on any three of the following:

e. General lighting in opencast workings.f. Precautions in case of sockets etc.g. Medical attention in case of injury.h. Notices of diseases.i. Notice & Order under Section 22 of the Mines Act, 1952.

Ans- a) General lighting in opencast workings:Good lighting in the opencast mines offers several advantages:

better safety because of better attentiveness. higher output as equipment is operated at optimum speed. reduced nervous strain on the operators and consequent better health of

workmen and better work attitude.The lighting system of open cast workings may consist of

general lighting of the quarry area and haul roads. local lighting of the operational areas of equipment .

As per Reg. 146 of MMR-1961 i) Adequate general lighting arrangements shall be provided during working hours at every opencast working.ii) The lighting provided in a mine shall be so arranged to prevent glare or eye strain.iii) Where electrical energy is available at the mine, the lighting arrangement shall be by electrical means. However, DGMS may vary this provision.iv) Every electrical lamp fittings shall be so constructed as to protect it from accidental damage and adequate precaution shall be taken to prevent lamps being damaged from shot firing.Standards of illuminations: - The standards of lighting to be provided in opencast mines during working hours at different places or area where natural light is insufficient., have been recommended by DGMS as per following details:-

Sl.No. Location Minimum Illumination Level /plane of illumination (Lux) (Horizontal /Vertical)

1. Operational area 5 H Of draglines & shovels, 10 V

2. Operational area of drills 10 V3. Operator’s cabin of Shovel, 30 H

Dragline, drill etc4. Truck haul road 0.5 – 3.0 H5. Operational area of

Bulldozer or other tractor mounted machine 10.0 At level of the crawler tracks.

6. Loading /Unloading/ transfer point. 3 H

7. Roadways and footpath from bench to bench 3 H

Lighting near the faces and haul road may be arranged by clusters of high pressure sodium vapour lamps located on the top of an adjustable telescopic mast, mounted on a platform with rubber tyred wheels or skids and having a portable DG Set.

Ans:-b) Precautions in case of sockets etc- There have been incidences of exploding of unused charge during drilling of relieving holes adjacent to misfired hole or a socket resulting into an accident.Reg. 168 of MMR’1961 prescribes the precautionary measures in this regard, which are enumerated below:i) Before the commencement of drilling in any working place, the competent person in charge of the place shall see that all loose rock is removed from the face and the area lying within a radius of 2 m of the proposed shot hole thoroughly cleaned or washed down with water and carefully examined for the presence of misfires or sockets. However, DGMS may grant a relaxation in this regard if deemed fit.ii) If any socket is found, it shall be dealt by drilling & firing relieving shot holes and careful search for cartridges & detonators shall be made in the presence of blaster amongst the material brought down by the shot. As far as possible, the search for detonators and cartridges and the loading of any ore, stone or debris which may contain a detonator shall be carried out without the aid of tools. iii) It is advisable that search for sockets should be made in big pieces of boulders also whether above ground or belowground before attempting to break them. For this purpose the boulders should be thoroughly cleaned or washed down with water and a careful examination made by a competent person for the presence of misfires of sockets. If any socket is found, it shall be dealt in prescribed manner.iv) The misfired hole or socket should be kept plugged by a wooden plug.v) No person shall bore out a hole that has once been charged or attempt to withdraw a charge either before firing or after a misfire or deepen or temper with any empty hole or socket left after shot firing.

Ans:- c) Medical attention in case of injury: Mining, being the hazardous industry poses threat to the safety of workmen. Rendering first aid in time to the persons receiving injury in mining operation is vital in saving life. First aid is the first assistance or treatment given to a casualty for any injury or sudden illness before the arrival of an ambulance or qualified medical expert. It may involve improvising with facilities and materials available at the time. First aid treatment is given to a casualty:

To preserve life To prevent the worsening of the condition To promote recovery

Rule 45 A of mines rules,1955 elaborates the following provisions related to medical attention in case of injury:

a) Every person receiving an injury in the course of his duty shall, as soon as possible, report the same to an official. If he is not in a position to report the same to an official, it shall be the duty of the person who first comes to know of it to report the same to an official. The official shall make such arrangements for rending first aid to the injured as may be required. If in the opinion of the official the injure is of such a nature as to require immediate attention by the medical practitioner, he shall arrange for the medical practitioner to be called.b) If an official who is required to carry a first aid outfit receives information about injury to a work person, he shall himself attend to the injured person.c) It shall be duty of the person in charge of the nearest first aid station to render necessary first aid to injured person.

Ans:-d) Notices of diseases- Ref. to Q.No.1(c) – 2nd Class (2009)Ans:-e) Notice & Order under Section 22 of the Mines Act, 1952.

For any matter for which no express provision is made in statute and it appears to the CIM or Inspector that such matter, thing or practice is dangerous to human life or safety or defective so as to threaten the bodily injury of any person in a mine, he may give notice stating the particulars of danger and requiring the same to be remedied in a manner and within the time frame as specified in the notice.

If mine management fails to comply with the terms of notice, the inspector may be order in writing prohibit employment of persons except those whose presence is necessary for securing compliance with the terms of the notice.

If depillaring or stopping operations are likely to cause crushing of pillars or premature collapse of any part of the workings or if adequate provisions have not been made against fire or flooding, the inspector may prohibit the extraction or reduction of pillars or blocks of minerals in any mine.

If the CIM or inspector authorized by CIM is of opinion that there is urgent and immediate danger to the life and safety of person, he may, by order in writing containing a statement of the grounds of his opinion prohibit employment of person in any mine till the removal of dangers.

Q2. A highly mechanized underground mine is planned to produce 5000 tones of ROM per day. A processing plant required to be installed in the leasehold area. Assuming your own conditions prepare an environment plan, keeping in view different factors affecting the environment.

Ans:- As per EIA notification 2006 issued vide Statutory order no. 1533 dt. 14 th

Sept’ 2006, by MOEF, Govt. of India, the following mining projects or activities requires prior environmental clearance from competent authority:

Srl.No.

Project Or Activities

Category with threshold limit Conditions

1 Mineral beneficiation

i) Category A: 0.1 mill. te/a mineral throughput.ii) Category B: < 0.1 mill te /a mineral throughput.

General condition shall apply (Mining proposal with mineral beneficiation shall be appraised together for grant of clearance)

General condition implies that any project or activity specified in category “B” will be treated as category A, if located in whole or in part within 10km from the boundary of :(i) Protected areas notified under the wild life (Projection) Act,1972.(ii) Critically polluted areas as notified by the CPCB from time to time.(iii) Notified Eco-sensitive areas.(iv) Inter state boundaries and international boundaries.All categories ‘A’ Projects or activities including expansion and modernization of existing Projects or activities and change in product mix requires prior E.C. from MOEF Govt. or the recommendation of an Expert Appraisal Committee (EAC) constituted by Central Government whereas category B Projects or activities & its variants requiring prior E.C. from State / Union territory Environment. Impact Assessment Authority (SEIAA) on the recommendation of a State/ Union territory level expert Approval Committee (SEAC) duly constituted.In general, the process of obtaining E.C. may be categorized under two heads, the first one being filling of Form l and preparation of Terms of Reference (TOR) of EIA report and second one being preparation of EIA report based on TOR approved by Competent authority. The EIA report consists of project descriptions, description of the environment, anticipated environmental impacts and mitigation measures, environmental monitoring programme, additional studies, Project benefits and EMP.Conditions given - Planned production – 5000 te mineral (ROM) per yearBeneficiation of ore – A processing plant is to be installed in the leasehold area Assumption of conditions:Type of land available – Agricultural, Forest etc.Processing plant – Consisting of primary and secondary crushers producing dust, noise etc.Surrounding area – Thickly populated, PAP’SWater source – River, Pond & canal Under the conditions as above, an EMP shall be prepared consisting of following components: (a) Project objectives, essentiality, scope and screening- The objectives of project are to produce 5000te of ore (ROM) per year from highly mechanized ug mine and also the produced ore to be beneficiated in crushing plant installed on the surface in lease hold area. It also includes location of the project site, its core zone and buffer zone.(b)Prevailing Environmental scenario:- The prevailing environmental scenario such as the ecological status ( sensitive and fragile areas), land environment ( geology, land form, land use, drainage pattern, soil characteristics), solid waste management system, water regime ( surface, sub-surface and u/g), liquid waste management, weather & climatic parameters, ambient air and noise pollution etc in both core zone and butter zone is studied and assessed.(c) Project description:- It describe geology, resources, production planning, layouts, outputs, inputs, economics etc and justification of the project.(d) Environmental Impact assessment:- Assessment of environmental attributes suck as social, ecological, land, water air, noise, waste etc is made without the Project activities to Project “ no action environmental scenario (NAES)” at various stages ( 5 yrs intervals) and projected NAES is indexed. Than, an assessment of environmental attributes with the Project activities is made to arrive at “ environmental scenario with Project (ESWP) at various stages and the projected ESWP is indexed. Finally, NAES & ESWP is compared and

analyzed. If needed possibilities of reorganizations, modification and redesign of Project activities is assessed so as to minimize the impacts.

EIA Study:-It consists of establishing quantitative values for selected study impact parameters, which indicate the quality of environment before during and after proposed mining activities.First of all, parameters are identified, qualified by giving weightage and the multiplication of the weightage with impact value for the particular parameters gives the impact score for that parameter and the summation of all impact score gives the environmental score for the project/mining activities.Parameters affecting the environment due to mining projects and the activities in the processing plants are:

Srl.No. Parameters Sub-parameters Impact valuei Air Dust, SPM, SOx, NOx etc. -3ii Water Suspended & dissolved solids,

COD, BOD, Ground & Surface water.

-3

iii Land Agriculture, forest, waste, Grazing, Marshy, Roads, Subsidence, Natural drainage system

-2

iv Noise & Vibration

Permissible noise level, safe vibration limits

-2

v Solid waste Reclamation, dumping, agricultural loss, soil depth.

-1

vi Flora & Fauna

Crops, rare plant species, wild life management, endemic & endangered animal species, migratory species, aquatic fauna.

-4

vii Socio economics

PAP, displacement, migration, employment and income generation, education.

-2

Impact value = + Observed concentration of pollutant Permissible limit of pollutant.( - ) Sign indicates the negative impact on the environment( +) Sign indicates the positive impact on the environment

The final impact assessment is calculated as follows:Sl.No.

Parameters Weightage(Wi) Impact Value (Ii)

Impact Score(WixIi)

Remarks

1 Air 150 -3 -450 Control measures reqd.

2 Water 150 -3 -450 Control measures reqd.

3 Land 100 -2 -200 Control measures reqd.

4 Noise & Vibration 100 -2 -200 Control measures reqd.

5 Solid waste 100 -1 -100 Under safe limit

6 Flora & fauna 100 -2 -200 Control measures reqd.

7 Socio economics 300 +4 +1200 Under safe limit

Total 1000 -400 Control measures reqd.

n Wi . li

Final impact index i = 1 x 100 = (-400 /1000)x100 = -40% n Wi i = 1 Hence, there is significant impact on the environment due to installation of processing plant on surface in the leasehold of mechanized ug mines planned to produce 5000te of ROM. (e) Environmental impact mitigation planning including detailed action plan

for- after calculating final impact assessment, the following mitigation measures are required to be taken : minimizing use of natural resources ( water, land, energy) mitigation measures including R&R requirements of P&M consumables, manpower finance requirement environmental monitoring, assessment and review process organization mine closure plan risk assessment/ disaster prevention management.

(f) Assessment of mitigation measures-The mitigation measures adopted for control the damage to the environment, assessment of the same are done from time to time. This includes selection of most suitable measures and its status. Apart from this, the following should also be taken into account:

assessment of inputs for taking mitigation measures – recurring and capital cost .

provision of monitoring of inputs for taking mitigation measures – recurring and capital cost .

provision of revision of inputs for taking mitigation measures – recurring and capital cost .

Q3. A large number of accidents/incidences are occurring due to hard landing of cages in different mines at frequent interval. List out the failures and remedial measures to prevent recurrence of such accidents/incidences. Assume your own conditions.

Ans:- Winding & haulage had been deployed in most of conventional U/G mine for transportation of men and materials. Although the accidents and fatality due to winding had been in low profile but the risk of hazards like breakage of rope, falling of cage, hard landing, over winding always exists.

In recent past, there had been incidences in which cages fell down in shafts. Incidents of such type are fraught with serious danger to human life and these are a matter of great concern for all of us.Conditions assumed:

Both man and material winding is done. Depth of shafts more than 300m. Type of winding – drum winding.

The failures causing accidents / incidents of hard landing of cages vis-à-vis remedial measures to prevent recurrence of such accident/incidents are given below:Failures/ reasons for hard landing of cages

Remedial measures for prevention.

1. Non-provision/non-functioning of cage catcher, pit bottom buffer and automatic contrivance.

a) Cage catchers having shock absorbing units should be provided in every vertical shaft or winze above the top most landing.b) Pit bottom buffers should be provided in every winding installation. Adequate facilities should be provided to keep the sump clear for safe working of the pit bottom buffers.c) Approved automatic contrivances should be provided in all men winding shafts inspective of depths.

2. High man-winding speed. Speed of man winding should not be more than the maximum allowable speed for a given depth.

3. Falling of cage aftera) over winding due to use of lower capacity detaching hook.

b) Free falling of cages after breaking the keps due to mismatch in detaching hook and catch plate.

After detachment of detaching book, projected fins of the hook must sit on the catch plate having adequate resting area on both sides. To have this adequate resting area, clearance between catch plate hole and detaching hook width should not exceed 4mm.Such resting area and position of catch plate should be checked during each recapping of winding rope and the measurements shall be recorded.

4. Failure of brakes due to improper maintenance of brakes.

5. Attempting to control the speed of steam winder by reversing the steam supply to the engine in the absence of proper braking system,, particularly

One or more brakes should be provided on the drum. Brakes should be normally “ON” type.Automatic contrivance including power brake should be provided with all winding engines used for man winding.

Such unsafe practices should be strictly stopped and strict vigil should be kept.

when the cage is near the landing.6. Deliberately keeping the emergency brakes defunct by spragging the reset lever of automatic contrivances.7. Non reliable depth indicator and dial gauge not showing the correct position of cage during its wind.

In shafts more then 100m depth, while ascending cage travels above the top most landings, the overwind switch shall be so set that in case of over wind the cappel band does not enter the catch plate opening. This mark shall be prominently made on pit top structure as well as on depth indicator dial..

8. Breakage of winding ropes due to :

a. Unsatisfactory head-sheave grooves causing wear and may also cause squeezing out of lubrication from the hemp core of the winding rope and thereby produce internal corrosion.

b. Large fleet angel causing wear.

c. Slipping of ropes on head sheaves causing wear.

d. Kinks on the winding rope may cause access of moisture and corrosive gases inside the rope thereby causing corrosion and pitting.

e. Corrosion due to unsatisfactory pit condition.

f. lack of lubrication causing corrosion.

g. Lack of regular examination to detect defects on the winding rope so as to discard the rope in due time.

The tread of the groove should amply support the rope. Support up-to 120 on the groove is satisfactory.

The fleet angle shall not exceed 1½ to avoid plastic as well as abrasive wear.

The head sheaves should not be unnecessarily heavy to cause slipping of rope on the sheaves during acceleration and deceleration of the speed of the rope.

While installing wire rope it should not be laid on the ground and then coiled on the drum. Instead the tope should be uncoiled from its reel and wound on the drum.

Suitable galvanized ropes preferably with independent wire rope core (IRWC) should be used. The condition of pit water should be regularly cheeked for acidity and alkalinity to facilitate selection of proper rope and proper lubricants.Outer surface of the rope shall be properly lubricated at regular intervals so as to protect the wires from moisture and gases.The frequency and the manner of examination of the winding rope should conform to the stipulations in the regulation and circulars.

Q4. Prepare a safety management plan for a large open cast mine. Assume your own conditions.

Ans: In the Indian Mining Industry health and safety standards as reflects in the death rate per thousand persons had attained a disturbing trend (ups & downs) during the last two decades. The legal and promotional measures taken by the Directorate General of Mines Safety and measures taken by mine operators (owners) including some proactive initiatives failed to improve further the accident scenario and had reached the limits of effectiveness. Considering the pros and cons of the enactment of more stringent statutory provisions, which may trial behind the suit, the growing technological innovations and alternatively allowing the operators to improve safety standards through implementation of standard operating guidelines/standard procedures, it has been felt that a break through could be achieved by introducing the concept of Health and Safety Management system through Risk Assessment and implementing the same by a team consisting of workers, supervisors and executives with specific responsibility and accountability. Safety Management Plan is a working document which outlines all the actions to be carried out to ensure the safety and health at the work place based on risk assessment exercise to be done by a team consisting of workers and mine managements besides others. This document is fundamental to the management of safety by the health and safety committee and management.

Assumption of conditions:-A big open cast mine is being worked by use of HEMM such as dragline, shovels and dumpers. Over the years it has been observed that occurrence of accidents due to use of machineries has increased. OB benches are worked by dragline while coal benches are worked by shovel-dumpers combination.Preparation of safety management plan for large open cast mine as assumed above- Risk Management is the systematic application of management policies, procedures and practices to the tasks of identifying, analyzing, assessing, treating and monitoring the risks.Safety Management Plan consists of following:

:

i) 1st step : Management’s Role- System Risk Review:a) Review of management’s safety policy- whether the company has framed and implementing the safety policy.b) Review of management’s Responsibility and commitment:- Management organizational structure & monitoring committees.c) Review of work by different committees.

ii) 2nd step: Hazard identification & Risk AssessmentThe process of identification of hazards is the most important part of the whole Risk Assessment Process.a) Statistical TechniqueThe techniques are important tools in measuring, controlling and improving organizations Health and Safety Performance.

b) Identification of causes & their prioritization: - In the table below, the details of accidents for last 10 years have been analysed, caused of accidents identified and prioritization of risks done.Causes of accidents Accidents Prioriti- Possible Hazards

expressed in %

zation.

Use of machinery including installation, repair and maintenance ( Dragline, shovel dumper etc)

F-45.8%S-22.9%R-37.0%

l Injury due to use of mobile equipment. Rollover, Collision, Run-over, Injury by impact of machine parts etc.

Fall of persons from height & fall/hit by object

F-9.1%S-17.3%R-36.0%

lll Injured by Projectiles, falling from height, caught in between etc.

iii) 3rd step: Development of Risk Management Action Plan:The use of machinery is at the top of the list of causes and the important hazards under this cause are – Rollover, Run-over, Collision etc.Risk has three components viz. consequence, exposure and probability.Risk has been assessed for each of the mechanism. Risk reduction has been planned through Risk Management Action Plan.

. Risk Management Action plan for Reduction of Accidents due to roll over.

Sl.No.

Hazards Mechanism Risk Rating Control Action Plan Responsi-bility

TimeFrameC E P T

1 Persons Injured in mobile equipment by Roll over

1.1 Fitness lapse

1.2 Brake, steeringfailure

1.3 Rever-sing compl-iance of procedures

1

2

2

10

10

10

7

7

8

70

140

160

a.Prohibition of drug b.Testing of work force c.Restriction on OT.

a. Good design b. Regular check & Testingc. Regular replacementd.Compet-ence of operator

a. Complia-nce of code on reversing

a.Issue directive b.Regular Testing. c. Man Power planning a. Designshould be standari-zed. b.Code of practice for check /Testing c. Regular repair & mainte-nance. D.Regular Training.a. Formu-late code of practi-ceb. Circul-ar and ensure compliance

Manager/Ex.Engr.(Exc) Engr.(Exc.) Agent & Manager

Ex-Engr(Exc.) AE(Exc.) Operator.

15days-do-

iv) 4th step:- Safety system Audit:Safety System Audit: Regular Audit to be introduced to monitor the status of implementation of different code of practices/Safe operating procedures and codes to be revised whenever required.v) 5th Step: Review by monitoring committees:Review of Audit Report in safety committee and tripartite meeting at area and company level to be done regularly and action to be initiated for implementation of Risk Management Actin Plan.

vi) Final step:- Repetition of All The steps:Analyse the status of safety and initiate action for improvement, as all the exercise in the system is for continuous improvement. The process should continue till the standards improved. The system with all the steps can be presented in the work flow Diagram:

Repetition

Q5. Write short notes on any two of the following:c. Winding rope, factor of safety, maintenance.d. Continuous environmental monitoring instrument in underground

mines.e. Mechanical ventilator, fan water gauge, efficiency of fan.

Ans:- (a) Winding rope:- Winding / hoisting ropes are built to withstand severe conditions and made of quality steel. At every shaft or winze rope used for winding purposes shall be of good quality and manufacture, free from any visible defect and of adequate calculated strength. While selecting winding ropes, its strength, resistance to external wear & corrosion, resistance to bending fatigue/ crushing/ rotation etc. should be taken into consideration. The attachment between the rope and the cage shall be of such type and be maintained in such manner as to obviate accidental disconnection. Every winding tope shall be made of cold drawn steel wire and gauge of the wires used in the construction shall be suited to the diameter of the drums, pulleys and sheaves of the winding installation except in a sinking shaft or winze less than 30m in depth.

In case of man winding shaft where guides are not provided, only non-spinning types winding rope shall be used.

Review of Management’s

System

Identification of Hazards &

Prioritization

Identifying mechanism & Assess Risk

Identifying Control & prepareing Action Plan

Carrying out Audit to assess status of implementation

Framing code of practices &

implementing

Fixing up Responsibility & Accountability

Revising Action Plan if required

Improved safety standards

Factor of safety of winding rope: It is the ratio of the breaking load on the rope at any point to the maximum static load on it when the cage is at the lowest working point. F= B / (H+W) Where F= F.O.S

B = Breaking load of the rope (Kg.f)= Specific weight of rope H= hoist depth.W=dead weight & payload.

The greater ability of longer ropes to absorb stresses allows reduced static F.O.S. with increasing depths in deep mines such as in metal mines.A higher F.O.S. is desirable for installations where there is frequent starting and stopping of the ropes (in shallow shafts) than for installations in deep shafts where there will be fewer winds and therefore fewer decking shocks. Hence in case of metal mines, variable F.O.S. commensurate with depth has been fixed as follows:Min F.O.S. Depth <10 not exceeding 300m <9 exceeding 300m but not exceeding 500m <8 exceeding 500m but not exceeding 700m <7 exceeding 700m but not exceeding 1000m <6 exceeding 1000m but not exceeding 1500m <5 exceeding 500m.Maintenance of winding rope:

Weekly examination - Each winding rope, by passing the rope at a speed not exceeding 1 m/s.

Monthly examination – Every winding rope, by passing the rope at a speed not exceeding 0.5 m/s.

Examination of recapping samples - Before recapping at length including the capping of at least 2m shall be cut off and shall be opened and its interval conditions examined.

(i) For every rope in use or intended for use, a certificate showing its breaking load, quality, construction and diameter (obtained from the manufacturer or supplier) and a history of its use, including a record of diameters of the drums, sheaves and pulleys used in conjunction with the rope, shall be kept in a bound paged book kept for the purpose. All entries therein shall be made and signed by the engineer or other competent person, and shall be countersigned and dated by the manager.(ii) If in the case of a new rope a test certificate as to the amount of its breaking load is not available, it shall not be used unless a portion thereof not available, it shall not be used unless a portion thereof not less than three meters in length, has been cut off and tested in a laboratory, institution or test house approved by the Central Government for the purpose.

(b) Continuous environmental monitoring instrument in underground mines- Underground mines have danger of heating, fire and gas poisoning. The traditional method of environmental monitoring by hand held instrument or by collection and analysis of air samples do not provide timely information

of their rising levels. Introduction of automatic continuous monitoring system have therefore being felt which helps in ensuring safety by: providing status of mine environment (qty. of gas, velocity of air,

humidity, temperature etc.) on minute-to-minute basis. giving timely indication of any change in the status of parameters for

timely withdrawal of man, cutting of power supply and swift corrective measures.

automated cutting of power supply providing early detection of problems before human injury occurs providing information on situations that develop beyond the incipient

stages to add the safe evacuation of persons and control and elimination of problems

Basically, the following continuous environmental monitoring instruments for UG mines are available.i) Atmospheric monitoring system (AMS): It typically consists of four major components: host computer, several outstation, a set of transducers and the computer software. These are integrated in such a way that it monitors the desired variables such as inflammable / noxious gases, oxygen, hydrogen, barometric pressure, smoke, air temperature, rock temperature, relative humidity, air velocity and air respirable dust concentration. During this monitoring if there is an increase /decrease on some critical parameters of the UG environment, the computerized systems are even now available to automatically regulate or the deregulate the air quantity in some part of the mine.ii) Tube bundle system (TBS): Tube bundles are made up of small bore ploythene tube (4-6 mm dia ), bunched together like wires in an electric cable and laid from a central station on surface or underground to various points from where samples are to be drawn. A small pump at central station draws samples of atmosphere through these tubes in turn and a highly sensitive infrared gas analyzer analyses and records concentration of inflammable, noxious gases & oxygen. The system of programmed to give alarm signals at set concentrations. Time interval between sampling and analysis can be from half an hour to two hours during which period an ignition / explosion can take place. Hence the system is now outdated.iii) Tele-monitoring system- The tele-monitoring system is a telemetry system to continuously monitor environment conditions in u.g. mines. The system broadly consist of:

Sensors and their associated units Outstation Surface computer.

In this system each sampling station (outstation) has a number of sensors (transducers) for different gases and for physical parameters of atmosphere such as temperature, humidity, air velocity etc. Sensors are powered by re-chargeable batteries of 12V, along with each sensor, its associated units such as digital display unit, analogue monitor, xenon flash beacon and audio alarm units are provided at suitable locations. Outstation

are powered by 7.5 Volt batteries. The sensor output is transmitted (tele-metered) through cables to control station computer on surface for display, recording and giving alarm signal. Each sensor is also fitted with a local digital display, calibration and alarm facility. Sensors are calibrated periodically.(c). Mechanical ventilator, Fan water gauge, efficiency of fan:Mechanical ventilator: - With depth, mine air temperature tends to achieve the temperature of the wall of air passage. Hot and humid air weighs heavily on the miners. Mechanical ventilator is used as an aid to replenish the air in the mines in order to clear away smoke, steam and dust, to dilute noxious/inflammable gases, to provide air containing a sufficiency of oxygen and to prevent excessive rise of temperature or humidity.Depending on the place of use and main applications in mine ventilation, mechanical ventilator can be classified into three main functional groups.i) Main mechanical ventilation/ main fan – It is normally installed at the surface of the mine. It may be either centrifugal or an axial flow type. Exhausting/ forcing type may be used. The main fan should be highly reliable as they are meant for continuous use throughout the long years of the operation. It handles large volume of air.ii) Booster Fan- It assists the main mechanical ventilator in the ventilation of a large district and improves the ventilation of a high resistance split. iii) Auxiliary fan- It is used to provide extra ventilation locally through duct when and where it is needed.Fan water gauge:- Fan water gauge is nothing but ventilation pressure in u/g mine. Water gauges are commonly used for measurement of ventilation pressure in mines and the readings are generally obtained in mm w.g. (1 mm wg = 9.8 Pascal)The atmospheric pressure in an u/g mine can be measured by the aneroid barometer. The difference of pressure between nearby points is however known by the water gauge which is essentially an ordinary glass tube of U-shape containing water and having one open end of U-tube connected to one point of low pressure and the other open end connected to another point having high pressure. The difference between the water levels of the two legs of the U-tube record the pressure difference between the two points. Water rises in the leg which is connected to the point of low pressure and falls in the other leg. A difference of 1 mm (started as 1mm of water gauge) represents a pressure difference of 1 Kgf/m2. A water gauge is placed in the fan drift; one end connected to the atmosphere and the other in the fan drift very near the fan (towards the mine)

In the case of a fan the total pressure or fan pressure or ventilating pressure is the difference between the mean total pressure of the fan and the mean total pressure of the air entering the fan. For the fan located on the surface, it is the difference between the atmospheric pressure and the total pressure in the fan drift. The total pressure is algebraic sum of static pressure (exerted by a moving fluid on a surface parallel with the direction of the movement) and velocity pressure (exerted by fluid by virtue of its motion.)

Efficiency of fans – In practice, theoretical characteristics of a fan are never achieved due to various losses such as hydraulic / friction losses, mechanical losses and leakage losses.

Hydraulic Efficiency- It is defined as the ratio of the total available head to the input head. Mathematically,

h = H/Hi

Vane Efficiency – The Ratio of the input head to the theoretical head is usually referred as vane efficiency although there is no actual loss involved. Mathematically.

va = Hi/He

Manometric Efficiency – Some times, the ratio of the actual total head to the theoretical head is termed as manometic efficiency, but this has no physical meaning and hence serves no useful purpose. Mathematically,

h = H/He = h. va

Volumetric efficiency- Leakage through clearances between the rotating and stationery parts of a turbo –machine causes capacity losses. Mathematically,

v = (Q)/(Q+QL) = Q / Qi where, Q = actual developed capacity of the fan QL = leakage capacity loss.

Mechanical efficiency- Mechanical losses are losses of power due to friction at bearings and disc friction which though strictly a hydraulic phenomenon is grouped with mechanical losses since it is external to the flow through the fan and does not incur a loss of head. It is thus the ratio of the power actually absorbed by the impeller and converted into head of the power applied to the shaft. Mathematically, m = ( input power – mech. losses) / input power.

Total losses is the ratio of the power in the air to the input power:

= h. v. m

Fan efficiency = Air HP / BHP of fan = QH/3.V.I.Cos

Overall efficiency = Air Power/ Input Power = Output/ Input to motor.

Q6. Are we moving on the right track in reducing accidents in the mines? Discuss. Describe different potent tools used by management for reducing accidents in underground mines due to fall of roof & sides.

Ans:- Appended below is the details of accidents in metal mines :

Year

No of accidents Accident frequency rate per

1000

Number of persons

Rate per 1000 persons

employedFatal Serious Total Killed Seriously Death Serious

persons employed.

injured rate injr.rate

1998 50 234 284 1.72 58 252 0.35 1.531999 59 207 266 1.69 70 228 0.44 1.452000 50 160 210 1.34 54 166 0.34 1.062001 62 178 240 1.76 72 186 0.53 1.362002 50 174 224 1.64 62 178 0.45 1.302003 51 147 198 1.45 61 163 0.45 1.192004 55 150 205 1.43 62 163 0.43 1.142005 47 93 140 0.99 51 98 0.36 0.72006 54 61 115 0.82 67 71 0.48 0.52007 34 45 79 0.56 40 62 0.28 0.44

From the above table, it may be inferred that i. Number of fatal, serious & total accidents has decreased to large extent.ii. Accident frequency rate per thousand persons employed has also

decreased from 1.72 (1998) to .56 (2007) iii Death rate per thousand persons employed has also decreased from .35

in 1998 to .28 in 2007.Hence, it may be seen from the above that we are moving on right track in reducing accidents in the mines.Different potent tools used by management for reducing accidents in underground mines due to fall of roof & sides:

After implementation of recommendations of various courts of enquiries, DGMS circulars, safety conferences, committee reports, reports of bi-partite and tri-partite safety committee, the rate of accidents in UG mines due to fall of roof and sides has reduced. However, for further reduction in accidents, management must use the following different tools in this regard:i) Setting up of strata control cell- In every mining company, strata control cell shall be established at corporate and area levels within 1 year to assist mine managers in formulation of Systematic Support Rules and for its implementation. Such cells shall be manned by adequate number of technical personnel headed by a senior official not below the rank of Chief General Manager at Corporate level and Dy.Chief Mining Engineer at Area level.

ii) Roof bolting as primary support- Roof bolting shall be used as a primary means of support for freshly exposed roof in development as well as depillaring districts. For the roof category “Poor” having value of RMR of 40 or less or where there is excessive seepage of water from the roof strata, roof bolts exclusively with resin capsules should be used to ensure adequate and immediate reinforcement of strata.iii) Side supports- Due emphasis should also be given to support the sides while framing systematic support Rules.

iv) No work below unsupported roof- Suitable steps shall be taken by the mining companies to inculcate the culture of no work at face other than support work, till the roof is supported by roof bolts right up-to 0.6m from the face.

v) Use of suitable roof bolting machine- To ensure proper drilling for roof bolting in all types of roof strata, suitable, fit for use roof bolting machines should be introduced in all mines within a period of one year. Such machines should be capable of being operated from a distance or be provided with suitable canopy to protect the drillers/roof bolters during drilling or bolting operations.

Procurement of mechanized roof bolting machine should be ensured as follows:

Quad Bolter for mines with continuous miner technology. UDM for mines with SDL/LHD. Portable hydraulic or compressed air drill for manual mines and mines

with different geo-mining conditions.

vi) Risk assessment- Risk assessment shall be carried out for assessing the risk from hazards of roof and side falls and for identifying control mechanisms with specific responsibility for implementation. This exercise shall be reviewed at regular intervals not exceeding one year. Periodical review of efficacy of safety management plan should also be done.

vii) Structured training- Each Company shall take steps to impart structured training to officers, supervisors and support personnel on roof bolting.viii) Mechanization of loading operation – The loading operation at the face should be mechanized by introduction of SDLs / LHDs and scrappers to reduce the number of persons exposed to green roof.xi) Using innovative / advance technology for safety-

Use of electronic surveillance to predict strata movement and monitoring impending roof fall particularly in depillaring districts.

Exploring suitable gadgets/equipment for identification of geological disturbances such as hidden slips.

Exploring suitable sensor based instruments/equipment for tracking people trapped underground.

xii) Improvement in quality of supervision & inspection: Closer and more competent supervision should execute frequently. Regular inspection should be made by the member of the safety

committee including Manager and Engineer. Workman’s inspector should inspect the mine regularly for identify the

deficiency and hazardous condition. Also I.S.O. should inspect each mine periodically for assessment of safety

status.xiii) Responsibility and Accountability- Responsibilities and accountabilities

for various aspect of safety among the mine employees should be defined and this should be also shared by the decision making authority down to the lower level of management.

xiv) Increasing workers participation in safety management: For enhancing safety standard in our mines, workers participation in

safety management through statutory and non-statutory forum should be increased.

In large mine section/department safety committee under main safety committee should be constituted for specific are of operation.

All mechanized mines and mines using HEMM, where 100 or more number of workers are employed, should be appointed workmen’s inspector for improving safety standard.

xv) Other measures- Making punishment for violation of provision of Mines Act very harsh. Increasing compensation amount to make accidents cost prohibitive. Motivating the key persons to achieve a greater degree of safety

consciousness.

Q7. During development (2.4m x 2.4 m) a 800 m long footwall drive for connecting ore passes of a blast hole sub-level stope, a Rocker shovel operator entered in the face for loading blasted rock mass and collapsed. Giving reason, write an enquiry report stating how such accidents can be prevented in future.Ans: Conditions given:-Method of work – sub level stopping Length of Footwall drive- 800m Size of Stope – 2.4mx2.4mMachinery used – Rocker shovel.Conditions assumed:-Depth of working – 300m Make of water - NormalDip of Vein - Steep Support System- Hydraulic stowing with mill tailings.Enquiry of Accident: - I would make enquiry about the accident in the following ways: -h) Background information- A copper mine (ug) was being worked by some

level stopping method by driving a stope (2.4mx2.4m) for driving a long footwall.

i) ii) Event prior to the accident- After drilling and charging of blast holes, blasting was done by shot firing crew under the supervision of mate and blaster.

iii) Occurrence of the accident:- On ……………. at about 9.30PM ( ll Shift) a last round of shots were fired in 10th level stope. After blasting, the mate, blaster, his helper and two drillers returned back. In the mean time, electric power failed resulting into stoppage of fan. Subsequently, the rocker shovel operator entered in the face for loading blasted rock mass and collapsed. Due poor ventilation, he got exposed to high concentration of blasting fumes environment for a longer period and suffered with their toxic effect. The operator was taken to hospital for treatment & he survived.

iv) Inspection and inquiry:- On next day, I met with the mate, blaster and his helper & drillers and recorded the statement of all of them. During the course of inspection, velocity & quantity of air was also measured at the place of accident and also at immediate out-bye ventilation connection from the face.

v) Possible causes of the accident:- Following are causes of accidents:a) Use of explosives in excess of permissible limit: - One of the cause of accident may be use of permitted explosives in excess of permissible limit as permitted by DGMS. b) Entry of rocker shovel operator without waiting for clearance of fumes: The rocker shovel operator had entered the face without waiting for clearing of blasting fumes. c) Ventilation requirement –Quantity of fresh air was not adequate at the face resulting into high concentration of nitrous fumes in air at face. d) Coursing of air- Blind heading was not ventilated by coursing of air upto 4.5m from the face.In my view, all the above factors collectively were responsible for such type of accidents.vi) Contraventions of statutory provisions:- The following provisions of the statute have been contravened in this case.a) MMR 166 : After shots have been fired, shot firer or any other person shall not enter the place until the atmosphere in the area is free from smokes & fumes.

b) MMR 131: Quantity of air was not adequate at the faces for clearing the blast fumes. c) MMR 136: Air current shall be coursed upto a point within 4.5m of the face by means of brattices or other materials.d) DGMS Cir.Tech.30/1973: Adequate arrangement should be made to circulate such quantity of air upto the site of blasting as to ensure after every round of blasting, dilution of ‘CO’ and ‘NOx’ in the blasting fumes to less than 50 PPM & 5 PPM respectively within a period of 5 minutes.vii) Suggestions for prevention of similar type of accidents in future:- By strict compliance of statutory provision mentioned at Point no. (vi) above, this type of accident can be prevented in future.

Q8. Due to large number of accidents a mine is declared as accident –prone. As a manager of the mine, suggest measures you will adopt to make the mine safer and accident free.

Ans:- A mine is declared accident prone on the basis of severity index which is a very useful statistical tool for identifying accident prone mines for special attention regarding accident prevention. For the purpose of calculating index of accident proneness by degree of severity, all fatal and serious accidents for last five years are taken into consideration. Assumption of conditions: Type of mine- U/G Nature of accident in last 5 years – Roof & side fall, inrush of water, fall of

persons etc.After declaration of accident prone mine, I as a manager of Mine shall adopt following safety measures to make the mine safer and accident free:i) Main thrust areas to reduce roof and side fall accidents

Creating awareness through extensive training of support personnel, dressers and supervisory staff.

Stress on steel supports. Steel supports to be introduced in all working districts.

Stress on safety by roof bolting. Quad Bolter for mines with continuous miner technology. UDM for mines with SDL/LHD. Portable hydraulic or compressed air drill for manual mines and

mines with difficult geo-mining conditions More emphasis on exploring / identifying appropriate technology/ equipment.- to get more accuracy in monitoring and analyzing inflammable and noxious gases. Use of electronic surveillance to predict strata movement and monitoring impending roof fall particularly in depillaring districts. Exploring suitable gadgets/equipment for identification of geological disturbances such as hidden slips. Using audio-visual alarms of global standards. Exploring suitable sensor based instruments/equipment for tracking people trapped underground.

ii) Measures against inrush of water Check surveys in all mines. Joint survey plans to be re-examined and updated.

Procuring more Burnside boring apparatus to probe water bodies u.g.

Preparing detailed action plan for preventive measures against inundation before onset of monsoon, proper implementation and monitoring.

iii) Measures to prevent explosion Installation of computerized continuous environmental tele-

monitoring systems in highly gassy mines.iv) Other measures:

a, Organizing two phased safety audits of mines as a continuous exercise.

- In the first phase, pointing out deficiencies and giving time for rectification.

- In the second phase, a review of implementation of corrective measures and submission of final report.

b. Completing risk assessment and safety management plans, follow-up for implementation and review.

c. Holding brainstorming sessions of chiefs of ISO of all subsidiaries to create impact and awareness and to evolve strategies.

d. Introduction of man-riding systems in mines involving arduous

travel.e. Attention to safety of contractor workers..f. Regular meetings. of Tripartite Safety Committees( twice a year)g. Proper training and re-training of workers, including contractor

workers. h. Critical analysis and documentation of even serious and near miss

accidents.

i. Monitoring status of recommendations of :o Tripartite Safety Committeeo CIL Safety Boardo Standing Committee on Safetyo Parliamentary Committee on Safety Conference.

THE MINES ACT, 1952 Morning Session

EXAMINATION FOR MINE MANAGER’S CERTIFICATE OF COMPETENCY (UN-RESTRICTED) UNDER THE METALLIFEROUS MINES REGULATIONS,1961

SECOND CLASS

MINE MANAGEMENT, LEGISLATION & GENERAL SAFETY(UN-RESTRICTED)

SUNDAY, THE 4th OCTOBER 2009 Full Marks: 100 Time: 3 Hours

First question carries 20 marks and is compulsory . (Answer any five other questions. Marks allotted to part/sub-question is indicated

at the end of each question)……..

Q1. Describe provision of the Mines Act and the Mines Rules in respect of following:e) Quality, quantity and storage of drinking water in mines. (4)f) First Aid Station. (4)g) Notice of certain diseases. (4)h) Employment of persons below 18 years of age. (4)i) Certifying surgeon. (4)

Ans:- a) Quality, quantity and storage of drinking water in mines- Following are the statutory provisions regarding drinking water:

i) In every mine effective arrangements shall be made to provide & maintain, at suitable points, conveniently situated, a sufficient supply of cool and whole some drinking water for all persons employed in the mine.

ii) Instead of drinking water being provided and maintained at suitable points for persons employed belowground, the chief Inspector may permit alternative effective arrangements.

iii) The quantity of drinking water provided shall not be less than 2 liters per person employed at any one time, and it shall be easily available during the whole of the working shift.It has been recommended by ‘ Technical committee on fatigue’ of Mines workers that supply of drinking water should be made on the scale of 3 liters per person if wet bulb temperature exceeds 30C.

iv) Where 100 or more persons are employed either above ground or in open cast workings at one time, an Inspector may, by an order in writing require the drinking water to be effectively cooled by mechanical or other means available.

v) All points where drinking water is provided, shall be legibly marked ‘DRINKING WATER’ in the language understood by majority of the workers. Such points shall not be within less then 6 meters of any washing place, urinal or latrine, unless permitted in writing by the chief Inspector.

vi) If drinking water is not provided from taps connected with constant water supply system, it shall be kept cool in suitable vessels sheltered from the weather. These shall be emptied, cleaned and refilled at least once in everyday. Steps shall be taken to preserve the water, the storage vessels and the vessels used for drinking water in a clean and hygienic condition.If the service of drinking water is not from a public water supply system an inspector may by an order in writing require the owner agent or manager of the mine to submit with the least possible delay a certificate from a

competent health authority or analyst as to the fitness of the water for human consumption.

vii) No charge shall be made for the drinking water supplied.Ans:- b) First Aid Station - Mining is a hazardous profession. There is every chance

of persons getting injury in mining operation. Rendering first aid in time to persons receiving injury is a must. Rule 44 of the mines rules 1955 elaborates the details in respect of first aid station, which are as follows:1) The first aid station shall be provided in the mines on the following scale:

A) Above ground:- One first aid Stationi) at the top of every shaft/incline where men or material are wound or hauled.

ii) in every workshop, screening plant and loading point. iii) at every other place, where more than 50 persons are employed at any

one time.. B) Open cast workings:- One first aid station for every 50 persons or part

thereof employed at one time.C) Below ground:- One first aid station- i) at the bottom of every shaft where men or material are normally wound. ii) at or near every plant. iii) near drive end of every haulage iv) in or at the entrance of every district/ section.However, no first aid station will be necessary within 300m of another such station .

2) At every first aid station there shall be provided and maintained first aid equipments as prescribed in the statute where injured persons may receive first aid treatment .

3) The in-charge of first aid station shall see that equipment provided at first aid station is kept in good order and is replenished whenever necessary. He shall render first aid to the injured persons. Names and designation of persons in charge of first aid stations should be prominently displayed at every first aid station.

4) An up-to-date list of all first aid station shall be kept in office of the mine & also displayed prominently at the first aid room

Ans:- c) Notice of certain diseases: Mining is a hazardous industry. Mining operation may lead to development of certain diseases among mine workers. In statute, elaborate provisions have been made for submission of notice of certain diseases to prescribed authority which are enumerated below: i) Where any person employed in a mine contract any notified disease the O/A/M shall within 3 days, give notice in Form V to CIM,RIM,DM, & IM (Med.)ii) If any medical practitioner attends on a person employed in a mine who is/believed to be suffering from such disease, he shall without delay send a report in writing to CIM, stating details of patient and disease.iii) Where the above report is confirmed to the satisfaction of the CIM by the certificate of a Certifying Surgeon or otherwise, the CIM shall pay to the Medical practitioner a max. Rs.16 for each x-ray and Rs.16 for each medical exam. The fee so paid shall be recoverable as an arrear of land revenue from O/A/M.

iv) If any medical practitioner fails to comply the above provisions, he shall be punishable with fine, which may extend to Rs.50/-

Ans:- d) Employment of persons below 18 years of age- i) No person below 18 years of age shall be allowed to work in any mine. However, apprentices and other trainees, not below 16 yrs of age may be allowed to work under proper supervision in a mine by the manager. In the case of trainees, prior approval of DGMS shall be obtained before they are allowed to work.

Ans:- e) Certifying surgeon:- A certifying surgeon is a qualified medical practitioner appointed by the Central Govt. for the purposes of the Mines Act’1952 and has jurisdiction within local or limits over the mines or class of mines assigned to him. With the approval of certifying surgeon he may authorize any quantified medical practitioner to exercise all or any of his powers for a specified period. No person shall be appointed to be or authorized to exercise that the powers of certifying surgeon who is becomes O/A/M of mine or is/becomes directly or indirectly interested /involved in any mining operation.Functions:- The main functions of certifying surgeons are :i) To medically examine and prepare the age and fitness certificates in

respect of :a) Such mine workers who in the opinion of an inspector are not adults, and b) Such apprentices or trainees who in the opinion of an inspector are not adults, and

ii) On the request of the CIM or an Inspector to carry out such examination as may be indicated in any mine or class of mines in which operations involve any risk of injury to the health of the workers.

Powers:- His powers are that he may make such inspection , examination or inquiry as he thanks fit in any mine assigned to him and the O/A/M of the mine must afford all reasonable facilities to the certifying surgeons for carrying out such inspection, examination or inquiry.

Q2. What are the benefits of risk analysis based safety management system? What is the status of implementation of safety management system in Metalliferous Mines in our country? Give strategies of efficient implementation of safety management system. (16)

Ans:- Risk analysis based safety management system is a structured process composed of well defined system that emphasizes continuous improvement in work quality, health, welfare and productivity of workforce engaged in mineral industry through setting up of improved safety standards and their effective implementation and administration. Because the statutory provisions can never be fully comprehensive, appropriate and site specific and the process of legislation making is often slow, these often trail behind technological innovations. Trends world over is therefore to make statutory provisions “flexible” by switching over from the regime of prescriptive regulation to goal setting legislation. Elements of risk analysis based safety management system: Health & Safety policy of the company and the mine. Roles and responsibilities of all levels in the organization. Specified competencies of staff. Safety committee, formation and role Method to identify and control risk Forward program to ensure actions to control hazards are carried out Emergency preparedness to cope with a hazard if it should occur Monitoring process for all identified hazards with or without residual risks

Identification of trigger points and resultant actions if these are reached Safety clearance for new equipment, work methods and materials used Accident statistics collection, analysis & actions Reporting and record keeping requirements Auditing and review process.Benefits of risk analysis based safety management system:- i) Improved work culture and supervision of hazardous jobs. ii) Casts specific responsibilities on the management. iii) Gainful utilization of resources on prioritized risks. More acceptable

because of involvement of grass root level and management. iv) Selection of best possible means to achieve better work environment and

reduced risk. v) Introduction of new technology with proven safety records expedited. vi) More reliance on team work. vii) Better concentration on use of systems, standards and safe practices. viii) Consistency and control for continuous improvement. ix) Reduction of incidents, accidents and their severity. x) Making the mines more efficient along with improvement of health and

safety status.Status of implementation in Metalliferous Mines in our country:9th Conference on Safety in Mines recommended adoption of Risk Management as a tool for development of appropriate Health & Safety Management System. Application of Risk management principles for systematic assessment and placement of geotechnical considerations in underground mine planning & design should receive due attention with adequate legal backing. However, status of implementation of the recommendations had been mixed. Initiatives have been by the DGMS and mining companies to educate stakeholders through seminars, workshops, training programme etc. In accordance to the recommendations of the 9th conference, the mining companies identified mines and with the help of officers of DGMS had conducted the risk assessment studies. However, implementation of the plan thus prepared remained wanting in most cases. The idea and the concept of the system were disseminated and understood by large number of stake holders but probably due to pre-occupation with production related pressures and expertise constraints the system could not find its deserved place in the industry.i) As recommended by 9th Safety Conference, risk assessment was done

and safety management plans made in some mines through consultants.ii) Employees were not fully involved.iii) Risk assessment has been done, but, framing and implementation of SMP

has not been done in some mines.iv) Risk assessment/safety management plans have not been reviewed and

updated.v) Commitment of top management is inadequate.vi) There have been 5 disasters since 9th Safety Conference.

Strategies for implementation:-i) Every mine should employ a sound risk analysis process, conduct a risk

assessment, and should develop a safety management plan to address the significant hazards identified by the analysis/ assessment.

ii) Management should commit itself for proper formulation and implementation of SMP.

iii) Management should allocate resources necessary for control measures.

iv) All employees should be trained with the help of national and international experts for optimal adoption of the safety management system.

Q3. Write short notes on the follow:d) Post detonating fumes. (5)e) Advantages of bulk loading of explosives in underground and opencast

metal mines. (5)f) Shock tube based delay initiation system for underground and opencast

mental mines. (6)Ans:- a) Post detonating fumes- The fumes generated after blasting is known as post

detonation / post blast fumes. In such fumes, NOx and CO are the main gases. The threshold limit value for Nox and CO are 5 PPM and 50 PPM respectively, but in post blast fumes, the percentage of these cases are much more than this permissible values. The amount of these gases produced varies with type of explosives, Completeness of detonation, cartridge materials and nature of strata. These harmful gases are diluted very quickly in the air.On complete detonation fumes produced are minimum. ANFO produces high amount of detonation fumes. Among the permitted explosives, permitted emulsion explosives produce minimum toxic fumes (NG based, slurry and emulsion explosives) produce fumes about 45, 32 and 27 litres/kg of explosives respectively). With increase in shelf life, toxic fume formation increases. Harder rocks produce more CO than softer rocks.In respect of post detonation fumes, the DGMS has issued the following directives:

ANFO should not be used for plaster shooting in belowground mines. In all mines, the manager should determine and specify the period of

waiting after blasting in any place after getting a special study done with the type and maximum amount of explosive used in any one round at any place underground.. The waiting period decided should be such that proportion of Nox and CO in the air at the end of such period at the working should not exceed 5ppm and 50ppm respectively.

No person shall enter or be permitted to enter the place of blasting during the waiting period so specified.

Manager should issue written instructions to all concerned to ensure that no person including the shotfirer/blaster takes shelter or otherwise remains in the return air from the place of blasting during the blasting operations and until the waiting period specified by the manager as above expires.

To reduce the production of post detonation fumes, proper detonator and fully charged exploder should be used so that detonators ignite properly, holes should not be overcharged and they should be properly stemmed.

Ans:- b) Advantages of bulk loading of explosives in underground and opencast metal mines:- In small opencast mines cartridge explosives meet the requirements, but in large opencast mines requiring huge quantity of explosives bulk loading systems are the only practical method.Bulk loading offers several advantages:1) Large quantities of explosive can be obtained at short notice. Pump trucks have swift charging rates of 200-300 kg/minute. Delivery of 50-70 tonnes in a single day is possible.

2) Tailor made products of required density and energy can be delivered down the hole to suit strata conditions.3) Full borehole coupling can be achieved enabling expanded burden and spacing parameters.4) There is better safety as non-explosives ingredients are stored at all stages.5) No inventory needs to be maintained and hence there is no investment in large magazines. Large number of vans is not required for transport of explosive.6) Manpower saving is obtained with less deployment of van drivers, helpers, blasting crew and magazine staff.7) There are no chances of explosive pilferage.In view of the advantages described above it is found to be very cost effective method.c) Shock tube based delay initiation system for underground and opencast mental mines:- The usual system of initiation of explosive in a large diameter hole is by using a detonating cord down the hole. At the end of the cord is the booster which is set off and in turn sets off the entire column. However, as the detonation passes through the cord in the hole, the explosive in contact with the cord gets desensitized and loses its efficacy. Part of the stemming may also get ejected causing premature venting of the explosive. The total loss of energy nay be from 10-50%.

The grammage of detonating cords has been progressively reduced from 15g/m to reduce the extent of desensitization but development of shock tube systems is a significant step forward.

Shock tube based delay initiation systems, also known as non-electric systems (non-els), have been introduced in India recently.

The system consists of a hollow polymer tube (3mm outer dia and 1.5 mm internal dia). A very fine layer of reactive material (HMX and aluminum powder) is provided in the annular space. A delay detonator is factory assembled at one end of the tube: the other end is sealed to prevent ingress of moisture of extraneous material. This detonator is put inside the borehole with a cap sensitive explosive to initiate explosive column inside the borehole. Plastic connectors are provided for hook up on to detonating cord trunk line.

This can be set off by the shock generated by detonator and detonating cord. Upon initiation, the reactive material propagates a milk shock wave with velocity of detonation 2000-2200m/s within the tube, which initiates the detonator.

These initiation systems are manufactured by ICI Explosives with trade name ‘Exel” and by IDL Chemicals with trade name Raydet in standard length 3m-45m.Advantages-1. Quantity of material inside the tube is very low (12-16 mg/m of tube against 6-

10 g/m in detonating cord), the tube is non-disruptive and reaction is contained within the tube. Hence there is no desensitization of explosive in a shot hole and no objection of stemming. Explosive energy is utilized better. Also flyrock generation is minimal.

2. True bottom initiation is achieved. Explosive is initiated at the floor level and it works for longer period giving good toe breakage.

3. Notice levels are comparatively low since detonation is confined within the tube.

4. Vibrations can be significantly reduced by providing 2-3 explosive decks in the same drill hole with shock tubes of different delays, making effective controlled blasting possible in opencast mines in vicinity of villages etc.

5. Being non-electric, they are immune to static electricity, stay currents and radio waves, and are also relatively insensitive to impact and friction.

6. Chances of cut off and misfires are less.Nonels have been used in opencast mines of NCL, SECL, SCCL and Kudremukh with encouraging results, even in dragline faces and are becoming popular now. They have been found useful in metalliferous mines of copper and zinc also.

Q4. Describe the occurrences of following gases in underground metal mines and their physiological effects:a) Nitrous fumes (6)b) Hydrogen sulphide. (5)c) Carbon monoxide. (5)

Ans:- a) Nitrous fumes – There are rarely found in mines and consist mainly of nitric oxide, nitrogen dioxide and nitrogen tetroxide. The original product is usually nitric oxide (NO) which quickly combines with oxygen to form red fumes of nitrogen dioxide (NO2) which have a pungent smell like that of fuming nitric acid. As nitrogen dioxide cools down it is slowly converted into colorless nitrogen teroxide (N2O4). Nitrous fumes are highly soluble in water and can be effectively allayed by water spraying.These are usually formed when explosives containing nitroglycerine (particularly dynamite) undergo combustion instead of detonation as may sometimes occur with weak detonators. It has been found that nitroglycerine when properly exploded produces 63.2% carbon dioxide and 31.6% nitrogen but when burning in its own gases, as occurs in a confined space such as a drill hole, it produces 35.9% carbon monoxide and 48.2% nitric oxide. Besides, nitroglycerine explosives with oxygen imbalance produce noxious fumes, an excess of oxygen producing nitrous fumes and a deficiency, carbon monoxide. Normally detonated ammonia gelatine explosives produce about 0.003m3 of nitrous fumes per kg of explosive. Nitrous fumes may also be found in small quantities in the exhaust fumes of diesel locomotives. The most vulnerable places in a mine where nitrous fumes may be found in fatal quantities are shafts and tunnels where heavy shot firing takes place in a confined space.

Physiological effects- Nitrous fumes are very poisonous, the maximum tolerable concentration for long exposure being 0.00025%. Concentrations of 0.025-0.075% are rapidly fatal. Men affected by nitrous fumes show immediate symptoms of cough, nausea, choking, perspiration and headache, but later develop serious bronchial troubles such as bronchitis and bronchopneumonia, which may prove fatal within 48 hours. The small quantities of nitrous fumes stimulate the development and growth of silicosis in dusty atmospheres. In Indian mines a tolerable concentration of nitrous fumes is taken as 0.0005% though in the U.S.S.R., it is still lower at 0.00025%.

Ans:- b) Hydrogen sulphide- It is rarely found in mines. It is usually produced in metal mines by the action of acid water on iron pyrites (Fes2+2H2O=Fe(OH)2+H2S+S), gypsum etc., by the imperfect detonation of gun powder and by blasting in heavy sulphide ores. H2S can also be produced by rotting of timber in water. Considerable quantities of sulphuretted hydrogen have been found in acid mine water particularly if such water has been lying stagnant in poorly ventilated areas. The gas being highly soluble in water is usually dissolved in the stagnant water and can be released in dangerous quantities by a slight disturbance, such as the fall of a piece of rock into the water. Seven miners were gassed to death in 1932 in a South African metal mine when tapping a large body of water which had

been standing for ten years in old workings. It can also been formed due to decay of organic matter. Incomplete detonation and burning of blasting fuse also produces H2S.Physiological effects- H2S is highly poisonous gas. Its allowable concentration as per USSR norms is 0.00066%. The poisonous effects of H2S on men are given below:

% of H2S Physiological effects0.01 Slight poisoning after 1 hour0.02 Poisoning after 1 hour without serious consequence.0.05 Serious poisoning after 30-45 minutes0.10 Cessation of respiration and death quickly occurs within 10 minutes

Ans:- c) Carbon monoxide- Timber fires can be dangerous sources of CO in metal mines. It is also present

in appreciable quantities in the exhaust gases of diesel locomotives or other diesel engines. Another source of carbon monoxide is blasting particularly if the explosive has a shortage of oxygen. Normally though most commercial explosives are oxygen balanced, they produce certain amount of CO depending on the state of detonation and confinement of charge. An explosive fired in a hole in a strong rock produces less CO than in a weak rock. Burning of explosive produces large quantity in CO. Physiological effects- It is a deadly poisonous gas because the haemoglobin in the blood has 250-300 times greater affinity for CO. forming carboxyhaemoglobin than, for oxygen forming oxyaemoglobin. Thus if CO.is breathed in large quantities for a sufficiently long time, the tissues, particularly those of the brain, get damaged due to lack of oxygen. The blood cells also get damaged after long exposure to CO. As a result, the patient suffers from headache, nausea, overstraining of the heart, mental disorder, loss of memory, paralysis, temporary blindness etc. leading to unconsciousness. A person affected by CO. does not realize it himself and his mental disorder makes him work harder so much so that he may have to be forcibly carried away. CO. imparts a bright pink colour to the blood and the patient looks fresh and flushed.Table below shows the degree of saturation that will result from different concentrations of CO and the toxic effects on human:

CO saturation in

blood %

% Concentration which can cause this saturation

level with time

Symptoms

10 0.004 Not noticeable apart from slight shortness of breath upon muscular exertion ( 4-5 hours.)

20 -25 0.012-0.014 Slight shortness of breath & palpitation, fatigue and feel like taking rest( 3-4 hours.)

30-33 0.028-0.04 Sever headache, quick fatigue, dulling of the intellect ( 3-4 hours.)

40-50 0.045-0.08 Intense headache, weakness, fainting upon exertion ( 1 hour)

60-70 0.1-0.112 Unconsciousness, with death after a time (30-40 min)

80 0.16 Immediate death ( 5 min.)

Q5. What is environment management plan? Describe salient features of environment management plan?

Ans:- As per EIA notification 2006 issued vide Statutory order no. 1533 dt. 14 th

Sept’2006, by MOEF, Govt. of India, the following mining projects or activities requires prior environmental clearance from competent authority:

Srl.No.

Project Or Activities

Category with threshold limit Conditions Competent authority.

1 Mining of Minerals

i) Category A: 50 ha of mining lease area.ii) Category B: < 50 ha 5 ha of mining lease area.

General condition shall apply

2 Mineral beneficiation

i) Category A: 0.1 mill. te/a mineral throughput.ii) Category B: < 0.1 mill te /a mineral throughput.

General condition shall apply (Mining proposal with mineral beneficiation shall be appraised together for grant of clearance)

General condition implies that any project or activity specified in category “B” will be treated as category A, if located in whole or in part within 10km from the boundary of :(j) Protected areas notified under the wild life (Projection) Act,1972.(ii) Critically polluted areas as notified by the CPCB from time to time.(iii) Notified Eco-sensitive areas.(iv) Inter state boundaries and international boundaries.

All categories ‘A’ Projects or activities including expansion and modernization of existing Projects or activities and change in product mix requires prior E.C. from MOEF Govt. or the recommendation of an Expert Appraisal Committee (EAC) constituted by Central Government whereas category B Projects or activities & its variants requiring prior E.C. from State / Union territory Environment. Impact Assessment Authority (SEIAA) on the recommendation of a State/ Union territory level expert Approval Committee (SEAC) duly constituted.In general, the process of obtaining E.C. may be categorized under two heads, the first one being filling of Form l and preparation of Terms of Reference (TOR) of EIA report and second one being preparation of EIA report based on TOR approved by Competent authority. The EIA report consists of project descriptions, description of the environment, anticipated environmental impacts and mitigation measures, environmental monitoring programme, additional studies, Project benefits and EMP. An EMP of a mine is in fact a guiding plan for undertaking the mining and associated activities with due regard to the environmental protection and management in and around the mining complexes. The EMP outlines the various actions that are required to be taken in mitigation of the environmental impacts of mining. The EMP is based mainly on the prevailing environmental scenario, the proposed mining and associated activities and assessment of their

impacts on the various environmental attributes. Hence, the study of the prevailing environmental scenario should be accurate and exhaustive so that the mining activities can be planned accordingly and the assessment of the impacts is realistic.EMP of a mine is a plan of actions to ensure that mining operations are carried out mitigating the environmental impacts of mining. It is submitted to competent authority as a part of application for environmental clearance of the project. It is prepared to generate base line data on the mine surface i.e. to know the basic parameters which is totally would mean “ environment” to monitor existing environmental and eco-system status, to check whether the parameters are within the stipulated limit and to recommend measures if the standardized limits are violated.Salient features of an EMP:- A good EMP should cover the following:-i. It should fulfill environmental goals and meet environmental performance

standards governing mining operations.ii. Time gap between first damage and commencement of environmental

protection measures should be minimum.iii Reclamation should as far as possible, be concurrent with mining

operations. Biological reclamation and not physical reclamation should be objective. Mining should be treated as interim land use and not the ultimate land use.

iv. Choice of mining technology and mining operations should meet environmental considerations. Project cost which should include environmental protection cost should justify and favour investment decision. Economics, Technology and Environment should be mutually reinforcing.

v. It should be amenable for periodic monitoring to gauge effectiveness of the measures implemented and permit additional measures to ensure fulfillment of environmental goals and attainment of environmental performance standardsTaking into account the above considerations, the EMP should describe the following:-.

(a) Project objectives, essentiality, scope and screening- This includes analysis of objectives and linkages for essentiality by examining various possibilities of meeting the objectives and linkage requirement from the sources other then the project. It also includes location of the project site, its core zone and buffer zone.

(b)Prevailing Environmental scenario:- Under the heading, the ecological status ( sensitive and fragile areas), land environment ( geology, land form, land use, drainage pattern, soil characteristics), solid waste management system, water regime ( surface, sub-surface and u/g), liquid waste management, weather & climatic parameters, ambient air and noise pollution etc in both core zone and butter zone is studied and assessed.(c) Project description:- It is nothing but the mine plan which outlines geology, resources, production planning, layouts, outputs, inputs, economics etc.(d) Environmental Impact assessment:- Assessment of environmental attributes suck as social, ecological, land, water air, noise, waste etc is made without the Project activities to Project “ no action environmental scenario (NAES)” at various stages ( 5 yrs intervals) and projected NAES is indexed. Than, an assessment of environmental attributes with the

Project activities is made to arrive at “ environmental scenario with Project (ESWP) at various stages and the projected ESWP is indexed. Finally, NAES & ESWP is compared and analyzed. If needed possibilities of reorganizations, modification and redesign of Project activities is assessed so as to minimize the impacts.(e) Environmental impact mitigation planning including detailed action plan for:

minimizing use of natural resources ( water, land, energy) mitigation measures including R&R requirements of P&M consumables, manpower finance requirement environmental monitoring, assessment and review process organisation mine closure plan risk assessment/ disaster prevention management.

Q6. (a) What is “restricted earth neutral system”- explain. (5)(b) What is maximum permissible earth fault current as per IER-1956 for- (5)

i) Open case mineii) Underground mine.

(c) Describe provisions of IER-1956 regarding earthling of electrical equipment in underground metalliferous mines (6)

Ans: a) The purpose of earthing is to eliminate danger to persons due to electric shock, if they come in contact with some parts of a machine or apparatus, which is normally dead but may get electrically charged and become live due to failure of insulation or contact with live parts. It gives protection against shock in case of non-carrying conductor takes current.Actually earthing alone is not a complete safeguard, and it is important that upon the occurrence of an earth fault in cables or apparatus, the faulty circuit shall be isolated automatically and with the least possible delay that can be ensured by means of automatic leakage trips.In our country the earthing of neutrals is governed by I.S.S. rules. System neutrals can be grounded by any one of the following methods:-i) Solid Grounding / Solidly earthed Neutral System.ii) Resistance grounding/ Restricted- neutral system.iii) ARC suppression coil grounding. Restricted earth neutral system- To provide an earthing system, the neutral point of supplying transformer secondary side is kept earthed by connection to an earthing mat (installed in an earthing pit on surface of the mine) and an earthing conductor runs along with power conductors. All metallic parts of electrical equipment are kept connected to this earthing conductor. When an earth fault develops, the earth current trips the earth relay in the controlling switch and cuts off the power automatically.In solid grounding, the neutral is connected to Earth pits by a direct metallic connection but the magnitude of earth fault current will be much higher. So, generally it is used for medium voltage substation of leaser capacity.The electric shock hazard and fault energy dissipation can be reduced drastically by inclusion of a fault current limiting impedance between neutral of the supply transformer (550V) secondary and earth. By choosing suitable value of neutral impedance, the earth fault current can be limited to 750 miliamperes and the maximum energy dissipated in the fault could be limited drastically.

In resistance or reactance grounding, resistance or reactance is used in between the neutral and the earth pits to restrict the earth fault current so that in case of earth fault the current may not be very high in the connected circuits. The only difference in resistance grounding and reactance grounding is that, the power consumption in the reactance does not take place. These types of grounding are done for comparatively higher voltage sub-stations capacity. Since the earth fault current level is very small in restricted-neutral system of supply, quite sensitive and reliable electronic circuits are usually employed in the protective circuits.The restricted earth neutral system restricts the earth fault current thereby reducing the chances of electrical shock, fire and damage at the fault point.

Comparison of solidly earthed neutral system and restricted- neutral system: Parameters Solidly earthed neutral

systemRestricted- neutral

system.Earth fault currents released with a 550V, 300 KVA transformer

Around 700 to 1000A Approx. 750 mA with a 424 ohm neutral resistor.

Voltage of healthy phases under earth fault condition.

Remains at rated phase volt.

May rise above rated phase volt.

E/F relay operating time Sluggish FasterDamage to equipment/ cable due to earth fault

High probability Nil

Chance of degeneration of earth fault into solid dead short circuits

Maximum Very remote

Are earth fault relays fail- safe?

No Yes

Earth fault relay setting ( at 550V)

5A 80mA

Fire danger High risk NilGas Ignition risk Very high risk Lesser risk.

b) Permissible earth fault current- Unit recently, Indian Electricity Rules, 1956 did not specify the maximum permissible earth fault current. But after amendments made in April’2000, Rule 116 specifies that the earth fault current shall not be more than-50 amps in 3.3 kv/6.6 KV systems in opencast mines

and750 milliamps in 550/1110-volt system for underground mines.

.The magnitude of earth fault current shall be limited to these specified values by employing suitably designed restricted neutral system of power supply.

The operation of the switchgear and the relays shall be recorded daily at the generating station, sub-station or switch station in a register kept for the purpose.

The effectiveness of the switchgear and the protective system shall always be kept and maintained in working order, shall be checked once every three months

and the result thereof shall be recorded in a separate register kept for the purpose.

g) Earthling of electrical equipment in underground metalliferous mines- Rule 115, 116 & 117 of IER’1956 stipulates provisions in respect of Earthling of electrical equipment in underground metalliferous mines, which are enumerated below:i) Method of Earthing & Protective Equipment:- UG mettalliferous mines shall have ‘restricted – earth neutral system’ of power supply connected to an earthing system at surface of the mine and so designed that the earth fault current shall not exceed 750 milliamps in 550/1100 v system. Appropriate switchgear shall be suitably placed in the mine to automatically disconnect the power when a fault, including an earth fault occurs. Operation of the switchgear and the relays shall be recorded daily at the generating station, sub-station or switch station in a register kept for the purpose. Effectiveness of the switchgear and the protective system shall always be maintained, it shall be checked once every three months and the results recorded in a separate register kept for the purpose.ii) Earthing Metal etc:- All metallic sheets, coverings, handles, joint boxes, switch gear frames,

instrument covers, switch and fuse covers of boxes, all lamp holders (other than those insulated by fire resisting materials) and the frames and bed plates of generators, transformers and motors shall be earthed by connection to an earthing system on surface of the mine. (Earthing system on surface shall be as approved by the Inspector.

When cables are provided with metallic covering, such metallic covering may be used as a means of connection to the earthing system provided that the metallic covering of every cable shall be electrically & mechanically continuous through out, efficiently protected against corrosion, having conductivity at all points and at all joints at least equal to 50% of the conductivity of the largest conductor.

The conductivity of any conductor of the earthing system shall be at least 50% of that of the largest power conductor of the system. Further, however, no conductor of an earthing system shall have a cross sectional area less than 0.15cm2. In case of a flexible cable of portable apparatus of voltage up-to 125 volts, the cross-sectional area and conductivity of earthing conductor shall not be less than of the largest live power conductor.

Joints in earth conductors & joints in metallic armouring of cables shall be properly soldered or otherwise efficiently made.

Switch, fuse, or circuit breaker shall not be inserted in any earth conductor. This rule shall not apply to system whose voltage does not exceed 30 volts.

Q7. Electrically operated L.H.D. is used in an underground mine producing about 0.5 million tonne of ore by practicing cut and fill method of stopping. Prepare a “code of practice” for deployment of such LHD, with emphasis of its operations on filled up area. Assume Footwall and Hanging wall rock to strong. (16)

Ans:- Conditions given :- Method of work – cut & fill method of stopping. Machinery deployed- Electrically operated LHD. Nature of footwall and hanging wall rock- Strong Planned production – 0.5mt of ore per year.

Condition assumed - Type of ore body - Thick veins Dip of ore body – Steep Strength of ore – Strong Thickness of ore body - 12m Depth of working – 500 m Support – Timbering & Hydraulic filling with mill tailings mixed with water

Type of LHD used – Front discharge type (2.0m3 capacity) with cable remote control system.

Since any method of stoping for extraction of mineral from metal mines is risky, a suitable code of practice for safe operation for LHD should be framed, got vetted by tripartite safety committee and implemented. The code of practice shall be as follows:-

i) Fittings of LHD- The LHD should be provided with safety & other protective devices are mentioned below: - dump lever with key/push bottom switch foot brake temperature switch oil level switch adequate front and rear light audio-visual alarm Portable fire extinguisher Dead man’s control where by power will be cut off automatically when the

driver leaves his seat.ii) Operation:- a) LHD shall be operated only by competent person authorized by the manager. He shall not permit any other person to ride on LHD or interfere with its operation. However during test and examination, it may be operated by an authorized competent person other than the driver.b) Before putting the machine in operation, the operator shall ensure that the machine and its accessories have been checked against a checklist and found in proper working order. c) Operator shall give a pre-start warning before starting the machine and give sufficient time to persons in the vicinity to move away. d) Trailing cable shall be protected from external damage during operation. Helper will use insulated gloves for handling the cable. He shall maintain safe distance from LHD in motion.e) During blasting, machine shall be parked at a safe place. f) When leaving the working place, the operator shall keep the machine in a safe position which does not endanger any person, lower the bucket to the floor, turn and lock levers to neutral position and cut off energy supply from gate end box. The same procedure will be followed at end of the shift.g) No person other than the operator shall be on the LHD when it is in motion unless permission has been taken from the manager.h) No person should be allowed to stand besides the machine while the machine is running. i) Control valve should not be used as a handhold while climbing on to the machine.iii) Ventilation:- Minimum requirements:- Quantity of air- Sufficient qty. of air as required in statutory permission granted reg. 107 of MMR’1961

Inflammable gas in general body of air- not more than 0.5%. LHD shall not be used out-bye of last ventilation connection.iv) Dust Suppression: - Water spraying up-to the face of blasting. v) Other safety precautions:- (a) Only approved type of hydraulic fluid shall be used.(b) LHD shall not be operated at a gradient more than 1 in 7, Roads shall be kept clean and free from hindrance. Vertical supports shall be avoided as far as possible.(c) No person shall cross the LHD during its movement.(d) It should be ensured that FLP features of LHD electricals/ gate end box are in proper order, trailing cable is connected with suitable connector and the machine is controlled by pilot circuit.e)There should be 1 m clear space on either side of the machine where it works so that vertical support, if any used are not dislodged.vi) Examination and maintenance:- LHD shall be examined in each working shift by competent person and once in 7 days by the engineer. It shall be maintained as per recommendations of the manufacturer. Records shall be maintained.

Q8. An underground mine is located near a seasonal river. Describe in detail,

what precautions would you take to prevent inundation in the mines (16)Ans:- Ingress/inrush of surface water may enter into the mine workings through the

mouth of the shafts / inclines / winzes, unplugged surface bore holes connecting the underground workings, subsidence cracks, pot holes etc. To guard against danger of inundation due to surface source of water, elaborate statutory provisions have been made. Besides this, additional precautionary measures have also been suggested by various courts of enquiry, committee, safety conference etc. The following precautions should be taken to prevent inundation in the ug mines due to surface source of water such as seasonal river:i) As required under Reg.127 (1) of MMR’1961 adequate protection against the danger of inrush of surface water in the form of dams / embankments shall be provided & maintained.

The embankment should be designed so as to withstand the likely head of water with a high factor of safety. The side facing the water should normally be pitched with stone to counter act or stand the scouring action of moving body of water.ii) All mine entrances / openings shall be maintained at a level at least 3m above the HFL.iii) All the workings of the mines within 15m of HFL or beneath the river shall be extended with the permission of the DGMS under the Reg.’127 of MMR’1961.

iv) If the working beneath the river is considered to be unstable, it should be stabilized suitably.v) All the boreholes not required for use shall be plugged completely.vi) Garland drains shall be maintained all around the mine entries and also around the winding engine rooms and boiler houses.vii) Cracks in the subsidence area on the surface shall be carefully blanketed, compacted and raised to sufficient height. Proper drainage system around it shall be arranged and maintained so that accumulation of water may be avoided.viii) All the potholes shall be properly blanketed and compacted. A proper slope shall be maintained in the area liable to pot holding to avoid accumulation of the water in this area.

ix) Warning level, withdrawal level and danger mark shall be fixed on the poles, which are fixed in the river and ponds. Poles shall be painted and lighted.x) Float alarm, signaling and communication system shall also be arranged.xi) Guard room shall be established in such a position, so that guard can easily watch on the HFL, danger mark and withdrawal level.xii) During heavy rain, the manager or senior most mine official present in the mine shall go round the surface areas of the mines to check vulnerable point and effectiveness of the safety measures.xiii) The protective measures and workings shall be inspected once at lest in every quarter by the manager personally.

` xiv) A competent person shall once at least in every (4days) during the rainy reason and once at lest in every 30 days during other periods of the year, examine every protective measure. Record shall be kept with the signature of person making the examination and countersigned by the manager.xv) Standing orders for withdrawal of persons from the mine shall be framed and enforced.xvi) Copy of standing order shall be displayed in the office of the manager, token office and conspicuous places.xvii) All concerned shall be familiar with standing orders. Mock rehearsals shall be held for this purpose almost once in every month during the rainy season and once in three months during other seasons.