KINGDOM OF CAMBODIA Ministry of Youth, Education and Sports Project ID: P144715

ENVIRONMENTAL AND SOCIAL MANAGEMENT FRAMEWORK Cambodia Global Partnership for Education Second Education Sector Support Project

July 25, 2013

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Table of Contents

1. INTRODUCTION .............................................................................................................................................3

2. ENVIRONMENTAL ASSESSMENT OVERVIEW ...........................................................................................3

3. ENVIRONMENTAL MANAGEMENT PLAN – BID SPECIFICATIONS ........................................................4

3.1 SITE CLEARANCE FOR UNEXPLODED ORDINANCE (UXO) ...............................................................................4 3.2 WATER QUALITY ..........................................................................................................................................7 3.3 ENVIRONMENTAL MANAGEMENT PLAN AND MITIGATION MEASURES ...............................................................8

4. SCHOOL SANITATION OPTIONS AND RECOMMENDED IMPROVEMENTS ........................................ 13

4.1 THE NEED FOR WATER SUPPLY AND SANITATION FACILITIES: ..................................................................... 13 4.2 OVERVIEW SCHOOL WATER SUPPLY AND SANITATION PROBLEMS .............................................................. 13 4.3 BACKGROUND – THE CAMBODIA CONTEXT ................................................................................................. 13 4.4 OPTIONS - EXCRETA DISPOSAL ................................................................................................................. 16 4.5 RECOMMENDED SITE SCREENING ............................................................................................................. 27 4.6 TREATMENT SELECTION RECOMMENDATIONS: ........................................................................................... 28

5. REFERENCES ............................................................................................................................................. 29

ENVIRONMENTAL MANAGEMENT PLAN

CAMBODIA GLOBAL PARTNERSHIP FOR EDUCATION SECOND EDUCATION SECTOR SUPPORT PROJECT

1. Introduction

The Cambodia Second Education Sector Support Project, hereafter referred to as the Project, is executed by the Ministry of Education, Youth and Sports (MoEYS) of the Government of Cambodia with funding from the Global Partnership for Education (GPE) which the World Bank administers. The Project will comply with applicable Cambodian environmental legislations and the World Bank Safeguards Policies. By design, the Project will not finance any activity which causes significant adverse environmental and social impacts. The Project potential impacts, if any, are expected to be site-specific, and localized at small to medium magnitudes and readily mitigable through good design and appropriate mitigation measures. Therefore, the project has been categorized as Environmental Category “B” by the World Bank classification. The Project will finance civil works sub-projects for the construction or rehabilitation of early childhood education (ECE) facilities, especially for disadvantaged population, and a pool of potential sub-projects sites has been identified. In order to ensure that the sub-projects which involve civil works would be implemented in an environmentally and socially sustainable manner, an Environmental and Social Management Framework (ESMF) has been prepared by the MoEYS.

2. Environmental Assessment Overview

The Project builds on existing environmental practices of MoEYS, In particular, MoEYS has adopted an Environmental Management Plan (EMP) developed under a project called Education Sector Support Scale Up Action Program (ESSSUAP) of which the current project is a follow-on. As part of environmental assessment exercise, the relevance of existing EMP its implementation experiences were reviewed. Since the current Project’s civil works activities are similar to those of the previous one in nature, the EMP was highly relevant. Sections on contractor specifications to address environmental issues for the project, including construction dust and noise control, waste management, site management, safety controls, provision of clean water and sanitation facilities, unexploded ordinance removal, and asbestos containing material demolition management have been assessed adequate. These are described in Section 3. To strengthen environmental screening for proposed civil works, a screening tool (environmental and social safeguards checklist for construction sites) have been developed and included as Annex. Moreover, to strengthen the implementation of good construction practices and preventative measure, the Environmental Codes of Practices (ECOPs) is included in Annex 2. The assessment also identified a set of areas for improvement, including: stronger enforcement of requirements outlined in the EMP, improvement of wastewater flow in toilet facilities, flood protection for drinking water wells, sanitation of latrines, training in the use and the maintenance of latrines. Therefore options for school sanitation and recommendation for improvements are described in Section 4. The assessment also found that the have been incorporated into MoEYS standard practices and can be applied for the Project.

The civil works for ECE facilities will be aligned with the MoEYS Education Facilities Plan. This activity will consist primarily of adding a preschool classroom at an existing primary school, and the construction will occur within existing primary school campuses. School design will include appropriate ventilation, lighting, sanitation facilities and ramps for students with disabilities. Based on updated EMP, the standard for sanitation facilities will also be strengthened. Under ESSSUAP, reviews of community-built ECE facilities (Community Preschools) were conducted periodically. The current Project’s environmental assessment found that the quality of these facilities and implementation arrangements for environmental safeguards were satisfactory–all communities received construction supervision training before the start of school construction. Appropriate supervision will be conducted throughout the construction cycle, and the contract documents should require regular and frequent supervision from provincial engineers and local engineer consultants, as well as the involvement of stakeholders at the school and commune level. Some training programs for school personnel, students and communities will be conducted throughout the life of the proposed Project to foster sanitary awareness, promote environmentally friendly schools, prevent the spread of diseases and reduce maintenance costs.

3. Environmental Management Plan – Bid Specifications

Contractor bid technical specifications for school buildings, latrines and water supply wells will include environmental provisions for demolition and construction techniques, unexploded ordinances (UXO), noise and dust, site and waste management, asbestos containing material management, cultural and historical resources, and provision of clean water and sanitation facilities. 3.1 Site Clearance for Unexploded Ordinance (UXO) Cambodia is known to have an acute UXO hazard in, including, but not limited to, the following provinces:

Siem Reap;

Preah Vihear;

Oddor Meanchey;

Banthey Meanchey;

Battambang;

Pursat;

Kok Kong;

Kompong Speu; and

Kompong Thom. Should the construction site, village, or the access road between the school site and village serviced by the school have a known or suspected UXO hazard, the Contractor shall be responsible for contacting MoEYS who should contact the police or a UXO disposal agency, such as the Cambodian Mine Action Center (CMAC), or Halo Trust, which performs UXO removal on request. The school area and the village, as well as the road from village to school will be cleared. An area surrounding the village will also be cleared (50 to 100 meters behind the homes) as needed and appropriate. The area cleared adjoining the road from village to school will vary from 20 to 100 meters into the forest. Areas that are still considered dangerous will be marked with warning signs.

Once the UXO clearance has been completed, the Contractor shall obtain a certificate of removal and deliver a copy to the Project Sponsor. 3.2 Environmental Management for Demolition and Construction– Urban Settings Dust: Some of the school renovation and construction projects may take place in urban settings. The windows of residences in these settings are typically open during clement weather. The open windows would make residents liable to airborne dust exposure from demolition and construction activities. Exposure to airborne dust has the potential to exacerbate and/or cause several health conditions, including asthma. Therefore, the principal overall demolition restriction will be that no visible dust will be generated from the demolition activities. Should demolition activities begin to generate visible airborne dust, the contractor(s) will cease the activity(s) which generate the dust: (i) until the dust is controlled with means such as water spray or (ii) another demolition technique which does not generate airborne dust is substituted. Noise is another concern near residential areas, existing classroom and in urban settings. The contractor shall limit: (i) hours of work when noise generation activity could take place to regular daytime hours, and (ii) sound levels during work to 60 dBA1. 3.3 Demolition Practices for Asbestos Cement (Transite) Roofing Material Asbestos, a fiber mined in several countries, has been widely used worldwide as a construction material and insulator because of its strength, durability and heat resistance characteristics. In recent years, evidence on the adverse health effects of exposure to asbestos has been mounting globally leading to urgent calls to cease production of the most-harmful asbestos types, limit the use of less-harmful asbestos (e.g., discontinued spraying of asbestos), and to impose strict exposure standards for workers handing raw asbestos and asbestos- containing products. Occupational exposure to asbestos by inhalation can cause asbestosis (scarring of the lung tissue), lung cancer, and mesothelioma (cancer of the lung’s lining). In developed countries, occupational asbestos exposure is thought to have peaked in the 1970’s but the effects of exposure continue to manifest themselves today with an estimated 30,000 new asbestos-related cancers being diagnosed every year. Fiber cement roofing material is present in some of the school buildings that will be demolished, particularly in the areas near Thailand. This roofing material typically contains asbestos fibers as reinforcement. If the Transite board materials encountered are not friable, that is, they can not be crumbled, pulverized, or reduced to powder by hand, then it is possible these materials can be handled so as not to become environmental concerns during demolition. Demolition methods which could cause these materials to become an environmental concern are prohibited in this project, and the prospective demolition contractors are to make their bids accordingly, or propose control and monitoring techniques that will assure these materials will not become environmental concerns. Demolition methods which could make these materials an environmental concern by crushing or pulverizing them so as to release asbestos fibers into the air are discussed below.

1 Maximum permitted noise level in public and residential area, Subdecree on Air Pollution and Noise Disturbance

Control, July 2000.

Non-friable Asbestos US EPA categorizes non-friable asbestos containing materials (ACM) as category I and category II. Resilient floor covering is considered a Category I and Transite board (roofing) is considered Category II ACM. The following is excerpted from EPA guidance on demolition of Category I and II asbestos materials:

CATEGORY I non-friable ACM Category I non-friable ACM includes resilient floor covering which contains more than one percent (1%) asbestos as determined by standard methods. Category I non-friable ACM must be inspected and tested for friability if it is in poor condition before demolition. If the ACM is friable, it should be handled as an environmental concern. Asbestos-containing resilient floor coverings must be removed before demolition only if they are in poor condition and are friable. If a facility is demolished by intentional burning, all of the facility's ACM, including Category I and II non-friable ACM, must be removed prior to burning. Additionally, if Category I or Category II non-friable ACM is to be sanded, ground, cut, or abraded, the material is considered an environmental concern and the owner or operator must:

(i) Adequately wet the material during the sanding, grinding, cutting or abrading operations.

(ii) Handle asbestos material produced by the sanding, grinding, cutting, or abrading, as asbestos-containing waste material.

CATEGORY II non-friable ACM Category II non-friable ACM is any material, excluding Category I non-friable ACM, containing more than one percent (1%) asbestos that, when dry, cannot be crumbled, pulverized, or reduced to powder by hand pressure. Category II non-friable ACMs (cement siding, transite board shingles, etc.) subjected to intense weather conditions such as thunderstorms, high winds or prolonged exposure to high heat and humidity may become "weathered" to a point where they become friable. U.S EPA requires that each owner or operator of a demolition or renovation activity involving asbestos material of environmental concern remove all such material from a facility being demolished or renovated before any activity begins that would break up, dislodge, or similarly disturb the material or preclude access to the material for subsequent removal. ACM need not be removed before demolition if it is a Category II non-friable ACM and the probability is low that the material will become crumbled, pulverized, or reduced to powder during demolition.

Use of heavy machinery during the razing process causes Category II non-friable ACM (transite board), but not Category I non-friable ACM (resilient floor tiles) to become an environmental concern. All Transite materials should be carefully removed without crushing or pulverizing the panels. If the contractor carefully removes asbestos-cement materials using tools that do not cause significant damage, the materials are not considered an environmental hazard and can be disposed of with other construction debris. However, if demolition is accomplished through the use of cranes

(equipped with wrecking balls, clamshells or buckets), hydraulic excavators, or implosion/explosion techniques, asbestos-cement products will be crumbled, pulverized or reduced to powder, and are an environmental concern. ACM Disposal Where demolition debris will be recycled, any asbestos remaining on the debris must be removed prior to any recycling that will sand, grind, cut, or abrade the asbestos or otherwise cause it to become an environmental concern by releasing asbestos fibers. Asbestos-containing roofing material may not be ground up for recycling into other products. Depending upon the contractors involved and the condition of the asbestos-containing roof debris, the debris may or may not be segregated from other demolition debris. If the asbestos-containing roofing material is not in poor condition and is not friable, it may be disposed of in a landfill which accepts ordinary demolition waste. In general, since cleanup activities such as loading waste debris onto trucks for disposal do not subject non-friable materials to sanding, grinding, and cutting or abrading, such materials are not an environmental concern. However, waste consolidation efforts which involve the use of jack hammers or other mechanical devices such as grinders to break up asbestos-containing concrete or other materials covered or coated with Category I non-friable ACM, are an environmental concern. In addition, operations such as waste recycling which sand, grind, cut, or abrade Category I or II non-friable ACM are an environmental concern. When these types of activities are performed, Category I and II non-friable ACM become an environmental concern. 3.4 Water Quality All existing stream courses and drains within, and adjacent to, the Site will be kept safe and free from any debris and any excavated materials arising from the Works. Chemicals, sanitary wastewater, spoil, waste oil and concrete agitator washings will not be deposited in the watercourses. In the event of any spoil or debris from construction works being deposited on adjacent land or any silt washed down to any area, then all such spoil, debris or material and silt shall be immediately removed and the affected land and areas restored to their natural state by the Contractor to the satisfaction of the Supervising Engineer. 3.5 Protection of Historical and Cultural Resources To avoid potential adverse impacts to historical and cultural resources, the Contractor shall:

Protect sites of known antiquities, historical and cultural resources by the placement of suitable fencing and barriers.

Adhere to accepted international practice and all applicable historical and cultural preservation requirements of the Government of Cambodia.

In the event of unanticipated discoveries of cultural or historic artifacts (movable or immovable), or human remains in the course of the work, the Contractor shall take all necessary measures to protect the findings and shall notify the Construction Supervisor and concerned provincial-level and

central government levels representatives of the [relevant authority (Address and phone Number)]. If continuation of the work would endanger the finding, work shall be suspended until a solution for preservation of the artifacts is agreed upon. 3.6 Clean Water and Sanitation Facilities for Construction Workers The contractor shall provide at the site potable (safe from a health standpoint) drinking water at a minimum rate of one gallon per day per worker. The Contractor shall provide a temporary privy facility if there are no existing facilities available at the construction site for the workers. The facility will be dismantled, pit filed and site cleaned to pass inspection of the Construction Supervisor when permanent privy facilities available for the construction workers are constructed and operational at the site. The privy shall be located more than 30 meters of an existing water supply well or surface water body, unless a lack of available site area or other extenuating circumstance prevents such a safety distance. Alternatives shall be approved by the Construction Supervisor. 3.7 Water Well Construction Arsenic and Turbidity Testing: The Construction Supervisor shall conduct, if deemed necessary, tests for physical and chemical quality of the drilled well water including turbidity and Arsenic content. In case the water well contains Turbidity of more than 10ppm the well will NOT be accepted and the builder must redevelop the well until the turbidity level becomes acceptable (less than 10ppm). No payment shall be made for a well that has Turbidity more than 10ppm. If the well water contains arsenic more than 0.05 mg/l, the well must be abandoned. In such case the builder can claim only for the payment of the drilling work. No payment shall be made for hand pump and platform construction in such a case. Well sterilization: The Construction Supervisor shall oversee the sterilization of the well with hypochlorite solution (household bleach) for at least twenty-four hours, after which the well shall be pumped to flush the residual chlorine. 3.8 Environmental Management Plan and Mitigation Measures The intent of an EMP and Mitigation Measures is to recommend feasible and cost-effective measures to prevent or reduce significant adverse impacts to acceptable levels. For purposes of the proposed Project for which environmental impacts are expected to be limited gauging from the previous experience, particular attention is given to outlining best management practices and design measures which should be put in place to ensure that environmental impacts are minimized during civil works activity and that human health and environmental concerns are fully addressed on an ongoing basis during project implementation. The Contractor will ensure, and MoEYS will monitor, that no acquisition of private land, damage to private assets including standing crops, or physical relocation of people, would occur under the construction of facilities (construction of primary schools, formal preschools, Community Preschool (CPS) shelters and District Offices of Education).

Best management practices and mitigation measures are detailed by activity in the following table.

ACTIVITY PARAMETER MITIGATION MEASURES RESPONSIBILITY

IMPLEMENTATION MONITORING

A. General Conditions

Safety risks due to presence of unexploded ordnance (UXO)

Any clearance that is required will be undertaken through the civil work contracts, with the help from MoEYS

CMAC/Hallo Trust MoEYS/Consultant

The contractor shall only commence site works after the UXO clearance firm has certified that areas are already cleared

CMAC/Hallo Trust MoEYS/Consultant

Notification and Worker Safety

(a) The local construction and environment inspectorates and communities have been notified of upcoming activities

(b) The public has been notified of the works through appropriate notification in the media and/or at publicly accessible sites (including the site of the works)

(c) All legally required permits have been acquired for construction and/or rehabilitation

(d) All work will be carried out in a safe and disciplined manner designed to minimize impacts on neighboring residents and environment.

(e) Workers’ PPE will comply with international good practice (always hardhats, as needed masks and safety glasses, harnesses and safety boots)

(f) Appropriate signposting of the sites will inform workers of key rules and regulations to follow.

Contractor MoEYS/Consultant

B. General Rehabilitation and /or Construction Activities

Air Quality/ Dust (a) During interior demolition use debris-chutes above the first floor

(g) Keep demolition debris in controlled area and spray with water mist to reduce debris dust

(h) Suppress dust during pneumatic drilling/wall destruction by ongoing water spraying and/or installing dust screen enclosures at site

(i) Keep surrounding environment (sidewalks, roads) free of debris to minimize dust

(j) There will be no open burning of construction / waste material at the site

(k) There will be no excessive idling of construction vehicles at sites

Contractor MoEYS/Consultant

Noise (a) Construction noise will be limited to restricted times agreed to in the permit

Contractor MoEYS/Consultant

ACTIVITY PARAMETER MITIGATION MEASURES RESPONSIBILITY

IMPLEMENTATION MONITORING

(b) During operations the engine covers of generators, air compressors and other powered mechanical equipment should be closed, and equipment placed as far away from residential areas as possible

Water Quality (a) The site will establish appropriate erosion and sediment control measures such as e.g. hay bales and / or silt fences to prevent sediment from moving off site and causing excessive turbidity in nearby streams and rivers.

Contractor MoEYS/Consultant

Waste management (a) Waste collection and disposal pathways and sites will be identified for all major waste types expected from demolition and construction activities.

(b) Mineral construction and demolition wastes will be separated from general refuse, organic, liquid and chemical wastes by on-site sorting and stored in appropriate containers.

(c) Construction waste will be collected and disposed properly by licensed collectors

(d) The records of waste disposal will be maintained as proof for proper management as designed.

(e) Whenever feasible the contractor will reuse and recycle appropriate and viable materials (except asbestos)

Contractor MoEYS/Consultant

C. Individual wastewater treatment system

Water Quality (a) The approach to handling sanitary wastes and wastewater from building sites (installation or reconstruction) must be approved by the local authorities

(b) Before being discharged into receiving waters, effluents from individual wastewater systems must be treated in order to meet the minimal quality criteria set out by national guidelines on effluent quality and wastewater treatment

Contractor MoEYS/Consultant

D. Historic building(s)

Cultural Heritage (a) If the building is a designated historic structure, very close to such a structure, or located in a designated historic district, notify and obtain approval/permits from local authorities and relevant Ministries and address all construction activities in line with local and national legislation

(b) Ensure that provisions are put in place so that artifacts or other possible “chance finds” encountered in excavation or

Contractor/Ministry of Culture and Fine

Arts (MCFA)/ APSARA

MoEYS/Ministry of Culture and Fine Arts

(MCFA)/APSARA/ Consultant

ACTIVITY PARAMETER MITIGATION MEASURES RESPONSIBILITY

IMPLEMENTATION MONITORING

construction are noted, officials contacted, and works activities delayed or modified to account for such finds.

E. Toxic Materials

Asbestos management

(a) If asbestos is located on the project site, mark clearly as hazardous material

(b) When possible the asbestos will be appropriately contained and sealed to minimize exposure

(c) The asbestos prior to removal (if removal is necessary) will be treated with a wetting agent to minimize asbestos dust

(d) Asbestos will be handled and disposed by skilled & experienced professionals

(e) If asbestos material is be stored temporarily, the wastes should be securely enclosed inside closed containments and marked appropriately

(f) The removed asbestos will not be reused

Contractor MoEYS/Ministry of Environment

(MoE)/Consultant

Toxic / hazardous waste management

(a) Temporarily storage on site of all hazardous or toxic substances will be in safe containers labeled with details of composition, properties and handling information

(b) The containers of hazardous substances should be placed in an leak-proof container to prevent spillage and leaching

(c) The wastes are transported by specially licensed carriers and disposed in a licensed facility.

(d) Paints with toxic ingredients or solvents or lead-based paints will not be used

Contractor MoEYS/Ministry of Environment

(MoE)/Consultant

F. Affects forests and/or protected areas

Protection (a) All recognized natural habitats and protected areas in the immediate vicinity of the activity will not be damaged or exploited, all staff will be strictly prohibited from hunting, foraging, logging or other damaging activities.

(b) For large trees in the vicinity of the activity, mark and cordon off with a fence large tress and protect root system and avoid any damage to the trees

(c) Adjacent wetlands and streams will be protected, from construction site run-off, with appropriate erosion and sediment control feature to include by not limited to hay bales, silt fences

(d) There will be no unlicensed borrow pits, quarries or waste dumps in adjacent areas, especially not in protected areas.

Contractor MoEYS/MoE/Ministry of Agriculture,

Forestry and Fishery (MAFF)

G. Traffic and Pedestrian

Direct or indirect hazards to public

(a) In compliance with national regulations the contractor will insure that the construction site is properly secured and

Contractor MoEYS/Consultant

ACTIVITY PARAMETER MITIGATION MEASURES RESPONSIBILITY

IMPLEMENTATION MONITORING

Safety traffic and pedestrians by construction activities

construction related traffic regulated. This includes but is not limited to Signposting, warning signs, barriers and traffic

diversions: site will be clearly visible and the public warned of all potential hazards

Traffic management system and staff training, especially for site access and near-site heavy traffic. Provision of safe passages and crossings for pedestrians where construction traffic interferes.

Adjustment of working hours to local traffic patterns, e.g. avoiding major transport activities during rush hours or times of livestock movement

Active traffic management by trained and visible staff at the site, if required for safe and convenient passage for the public.

Ensuring safe and continuous access to office facilities, shops and residences during renovation activities, if the buildings stay open for the public.

4. School Sanitation Options and Recommended Improvements

4.1 The Need for Water Supply and Sanitation Facilities: Childhood disease rates highlight the importance of sanitation for prevention of waterborne disease in Cambodia: gastroenteritis is second only to acute respiratory infection. The importance of access to clean water and sanitation is emphasized by a recent World Bank study on the poverty/environmental nexus in Cambodia:

“[The study mapped] total cases of childhood diarrhea, population without access to clean water, and population without access to toilets in Cambodia. [This mapping] suggests a close spatial correlation between poverty and lack of access to clean water. Regression analysis … also indicates that poor households have much less access to safe water than higher-income households in Cambodia. The implications for child mortality are suggested by [mapping], which displays the regional distribution of childhood deaths in Cambodia. Again, the spatial correlation with the poverty population is evident. We conclude that safe water is a poverty/environment nexus issue of great importance in Cambodia.” “… we should note the difference between the spatial distributions of poverty and mortality rates, and the spatial distributions of total poverty and mortality. The latter provide the basis for our welfare analysis, because they reflect the total number of people affected. By this criterion, the central population axis of Cambodia is the high-priority area for addressing both poverty and mortality from lack of clean water and sanitation. Poverty and mortality rates, by contrast, are generally higher in the northern and eastern parts of the country. The proportion of households affected by poverty and waterborne disease … is higher in these areas, but the total number of affected households is much lower than in the central population axis.2”

4.2 Overview School Water Supply and Sanitation Problems

The Project schools share problems with schools in developing countries worldwide:

water supply is either non-existent or inadequate for the number of school children; toilets and latrines do not function properly due, for example, to a lack of water for flushing; latrines are padlocked because children are not trusted to use them properly; children, specifically girls, do not attend school because appropriate and private sanitation

facilities are lacking (WHO, 1997).

The provision of safe water and sanitation facilities combined with good hygiene education inevitably improves the health and attendance of children and may potentially result in a lower drop out, especially of girls. In essence, it is the combination of hard and software components that prevent water and sanitation-related diseases (UNICEF and IRC, 1998).

4.3 Background – the Cambodia Context

Environmental Conditions: Since under the grant schools/classrooms will be built and renovated throughout the country, the sites will cover an entire range of soils and hydrology. The most problematic areas for water supply and sanitation are the flood prone areas, where the water table

2 The Poverty/Environment Nexus in Cambodia and Lao People’s Democratic Republic by Susmita Dasgupta, Uwe

Deichmann, Craig Meisner, David Wheeler, DECRG World Bank Policy Research Working Paper 2960, January 2003.

recedes to the point where wells fail in the dry season. In these areas the schools are built on stilts three meters above the ground to survive the wet season floods. In different areas the length and depth of inundation varies; however, in many areas the children go to school via small boats. One purpose of raising the seasonally flooded classrooms under the program is to make a regular-length school year available. Another purpose of raising the classrooms on stilts is to protect the classroom buildings from flood damage. Building on stilts is well understood in the area, and there is a local industry of manufacturing reinforced concrete stilts.

In the Province of Kampong Thom where some schools flood from June through September or longer, soils range from sand to well-drained soils (in the dry season) to some clay deposits, used for bricks. Water Supplies About 30% of the schools have a water supply, consisting of pump wells supplied by UNICEF or on that model, open dug wells or open ponds. Where groundwater supplies are too deep, cisterns are used, supplied by roof runoff. Children bring their own drinking water to school from their homes, and water supplies at schools are generally used only for grounds irrigation and flushing the latrines.

Options for Improved Water Supplies: Water supply/conservation could make maximum use of:

maximize supply (well water and capture of rainfall runoff); maximize storage (tanks or cisterns), consider use of well pumps that can pump well water up into a storage tank; conservation and reuse, such as use of gray water from washing for irrigation, or untreated

cistern water for wastewater flushing (if a excreta disposal with water carriage is used).

Water Supply Systems in Seasonally Flooded Areas: Surface water entering wells is the main source of pollution. Flood water is likely to be contaminated, and could contaminate wells via inundation of the pump. The following are options for design changes and specifications to maintain safe water supplies:

Consider elevation of the water supply well pump and apron in areas of flooding; to avoid contamination by flood water and allow user access during floods;

Identify vendors of low cost bacteriological screening kits, and;

Identify a well sterilization (chlorination) technique and recommended frequency, to restore wells that have become contaminated and/or use rainwater collection tanks for latrines.

Sanitation - Excreta Disposal

Onsite school wells tend to be used only for latrine flushing and grounds irrigation, and children bring their own daily drinking water from their homes. Lessons learned concerning sanitation systems currently in use include poor operation of the school latrines, resulting in requirements for maintenance every three to five years. During the wet season percolation is poor, preventing flushing, and during the dry season, with little or no flush water, solids build up and have to be removed.

Plumbing - a Basic Problem in Design:

Design flaws in the plumbing of the water carriage latrine designs currently in use for construction of schools in Cambodia is probably the major source of dissatisfaction with these sanitation systems. The plumbing becomes clogged and the latrine becomes unusable.

Recommendations for Plumbing Improvements:

For water carriage systems, there should be a trap either within the toilet fixture or in the plumbing directly connected to the toilet fixture. This trap holds water and prevents sewer gas from escaping into the latrine room (see figures 1 and 2). The toilet plumbing should be vented to avoid siphoning the water out of the traps.

A standard cleanout, which consists of the same four-inch diameter PVC pipe with a threaded cleanout port in the top, can be located directly downstream of the toilet fixture, to enable bypassing the trap in order to auger the rest of the drain pipe to the septic tank. Additional cleanouts can be added where needed, with access through a covered manhole, but these should all be standard PVC cleanout fittings that do not alter the flow in the drainline. There should be no "cleanout" boxes in the plumbing prior to the outlet into the septic tank, as these will slow flow, collect solids and clog the plumbing.

Eliminate the box located directly under the toilet fixture, this box slows flush water flow and will collect solids and prevent complete flushing of wastes into the septic tank, if available;

Eliminate the cleanout box that interrupts the pipe run to the septic tank, as this will slow flow, collect solids and clog. Use standard PVC cleanout fittings where required for convenient auguring of the drain pipe instead;

Waste pipe diameter should be 4 inches, with slope of at least 1/4 inch per lineal foot, the greater the slope the better;

Built-in and encased plumbing should not be approved;

The most sanitary seats, particularly for children, are the U-shaped type made of nonabsorbent material;

At least one washbowl should be placed near the toilets. The number of washbowls should at least be equal to the number of classrooms in the building;

Toilet paper, towels, and liquid soap are necessities in toilet and washrooms.

Figure 1. Toilet Fixture with Built-in Trap

Figure 2. "P" Type Trap and Vent

4.4 Options - Excreta Disposal

Excreta Disposal Without Water Carriage

While disposal with water is desirable, it is not practical under many conditions. It is possible; however, to dispose of body wastes in such a manner that danger of carriage of disease from the excreta by surface washings, soil and water pollution, fowls, animals, and flies will be eliminated or minimized. Pit Privy: The pit privy consists of a hole dug in the ground over which the toilet seat is placed and in which the excreta are deposited and dried out, provided the pit is above the ground-water level and that flooding, surface washings and rain are excluded. This type of disposal is not suitable for flood-prone areas. The "improved" pit privy consists of concrete for slab and riser. A four inch vent is used from the riser to above the roof. Pit privies require little maintenance. The ventilation should keep the pit materials dry and small in bulk, consequently a pit should serve for 10 years or more, particularly if toilet paper is used, and no garbage or other refuse is thrown in. Water should be prevented from entering so far as possible, and mosquito breeding can be a problem. Screening the ventilator and keeping the seat cover down can discourage mosquito breeding. Disinfectants should not be used in the pit. Addition of ash or lime can help keep the contents dry. Vault Toilet: Devised to prevent the possibility of pollution of soil and ground water, the vault toilet consists of a watertight concrete vault over which the seat and house are placed. There is a cleaning door on top of the vault. The vault is vented through the roof. The vault contents will become liquid rather than dry. As a rule the cleaning door and the seats are not well maintained, resulting in proliferation of flies that are potential disease vectors. The vaults must be periodically emptied, which can be a dangerous nuisance, especially if they overflow. Composting Toilet3: The composting toilet is a variation of the vault toilet, however, a separate provision must be made for urine disposal. Details from a World Bank project in water supply and sanitation are shown below.

3 http://www.clean-water-for-laymen.com/composting-toilet.html

Features: Raised level base with access steps

Two chambers to alternate usage with composting Chambers must be maintained completely dry, so urine must be separated from feces in toilet bowl Users must add frequent layers of ash to dry feces When chamber is full, left to compost for > 6 months

Conditions: Must be used in flood-free areas Requires training for entire family

Requires significant labor input (stirring contents, rotating chambers) Preferably for areas where there is a need for cheap compost Benefits: Reduced odor and fly problems Free source of organic compost Long life if well-maintained Separated urine can be captured and used as insecticide Problems: High maintenance required (to stir and mix ash frequently) Urine separation impractical/unacceptable (especially women) Inadequate composting can present serious health hazard Liquids can destroy the ‘dry composting’ process4 Septic Privy 5 : There are variations of this concept, which are a bucket flushed toilet fixture connected to a septic tank via a 4 inch PVC pipe (a water carriage system discussed below), or the earlier version, which was a privy seat located directly above a septic tank. Only small amounts of water are required to maintain the older version of the septic toilet, since water is not used to carry the excreta to the septic tank. In the older version, small amounts of water are added to aid the digestion process. The tank is constructed of concrete with a capacity of 26 cubic feet (200 gallons), for 5 people. For each additional person an extra 3 cubic feet of capacity is added. The tank overflows to a filter, such as

4 Source: Steve Maber, Water for Sanitation and Health Project, World Bank

5 http://www.sswm.info/category/implementation-tools/wastewater-treatment/hardware/semi-centralised-wastewater-

treatments/s

a leach field (discussed below). A baffle is placed within the tank to prevent travel of waste directly from the place of deposit to the outlet. The digestion is anaerobic, so the tank should be vented through a stack so odorous gases can escape. Maintenance of the older version is simple but absolutely necessary to ensure proper operation. When first constructed the tank should be filled with water. Two buckets of water should be added to the tank daily (5-person size), or serious clogging will result. Use of newspaper will also cause clogging, only toilet paper should be used. No disinfectants can be added to the tank, since they will kill the bacteria digesting the waste. Sludge must be bailed or pumped out after several years of operation. A heavy scum may form on the surface of the tank contents upon which feces may accumulate, with consequent production of odors. This scum layer must be thoroughly broken up. Flies must be excluded from the tank by tight covers, and mosquitoes may breed in the tank and must be controlled.

The Septic Privy: Note This System Does Not Use Water to Flush.

Excreta Disposal with Water Carriage Cesspools6: In the privy design currently in use by the Cambodia Ministry of Education, a septic tank is connected to a second tank with graded gravel in the bottom. The operation of this second chamber is similar to a cesspool. A cesspool is the reverse of a well. The liquid wastes are run into a hole in the ground from which they seep off into the ground water. In the course of time the pores of the soil surrounding the cesspool may choke up causing overflow, a common occurrence where cesspools are in use. The remedy is to dig a new cesspool. Leaching cesspools cannot be

6 http://labspace.open.ac.uk/mod/oucontent/view.php?id=453841&section=1.7.2

recommended in communities where wells are used for water supply, since their action depends on discharge of sewage into the ground water. When poorly covered they allow odors to escape and are breeding places for mosquitoes. Septic Privy: The newer version of the septic privy includes a toilet bowl fixture with built-in trap (optional7), or a "P" trap. A bucket of water is used to flush the toilet fixture and convey the excreta though a short drainpipe to the septic tank located directly behind the privy. Photos of a household installation are shown in Annex 1. This design is similar to the one in use by the Ministry of Education and Save the Children in Cambodia, with some notable exceptions. The following changes would improve the current Cambodian Ministry of Education model:

There should be no box below the toilet fixture to accumulate feces, the toilet fixture is connected directly to the drainpipe, if possible;

The slope of the plumbing to the septic tank should be steep;

There should be no inaccessible "encased" plumbing, such as the box directly under the toilet fixture in the Cambodian designs.

Septic Tanks8: The septic tank is a convenient primary treatment unit for a water carriage system. Septic tanks are also known as tight cesspools to distinguish them from the leaching cesspool described above. The septic tank is usually constructed of concrete, although brick is sometimes used. When constructed of brick the inside should be carefully plastered with Portland cement mortar in order to make the tank as tight as possible. The sewage runs into the tank, is retained for a predetermined period, and is then discharged from the opposite side. During the period of retention the solid matter settles to the bottom where digestion by anaerobic bacteria takes place. This results in transforming a percentage of the solids into liquids and gases, and the indigestible residue is a black semi-liquid known as sludge. The tank must be designed with care, with knowledge of the principles involved, and above all, it must not be considered as a final treatment.

Source: http://www.sswm.info/category/implementation-tools/wastewater-treatment/hardware/semi-

centralised-wastewater-treatments/s

7 The ceramic fixtures with built-in traps were built locally in the project area in Honduras.

8 http://www.engineersdaily.com/2011/01/septic-tank-overview.html

Septic Tank Capacity and Dimensions: If the capacity of the septic tank is not properly designed, the tank will fill with solids, digestion will not be completed, and either the downstream filter (such as a leach field) will clog, the septic tank will clog or become a mere conduit for raw sewage, or both. The tank should hold an amount of sewage equal to the production in 24 hours. The amount of sewage produced per capita, per day must be estimated conservatively, to ensure proper operation and maximize the periods between maintenance sludge removal. A minimum of 400 gallons should be maintained, and in rural schools a rule of thumb has been 20 gallons per day up to 20 persons, thereafter the allowance may be reduced to 15 gallons per person. Careful consideration should be given to the dimensions of the septic tank as they govern the velocity of flow through it and also the vertical distance which suspended matter must travel to the bottom. Sludge accumulation will reduce the working depth of the tank. The depth should be sufficient so that the sludge accumulation will not unduly lessen the cross-section of the tank. On the other hand, it the tank is made too deep, especially in a tnk of small capacity, a current will be set up from inlet to outlet with little or not retention period for digestion of solids. A clearance of 8 to 12 inches between the surface of the sewage and the cover of the tank should be maintained to allow for the floating scum. Tanks are usually rectangular with the width approximately half the length. Cylindrical tanks of proper size will give satisfactory service. Septic Tank Effluent: Septic tank effluent has not been purified to acceptable levels to release into the environment. A portion of the suspended organic matter has settled out, but the matter still in suspension and in solution is still present and is still putrescible. Bacteria are present in the effluent in great numbers, there is no assurance that all pathogenic bacteria have been eliminated. There will also be suspended matter that gives the effluent a dark color. If left to stand, the musty odor will increase to offensive proportions. Further treatment is necessary to oxidize and make inoffensive the remaining organic matter, and further reduce any pathogens. This treatment is usually in the form of a biofilter, using a leach field in soil (subsurface irrigation), a sand filter (box, mound or buried), or a trickling filter, a variation of which is called a vegetated submerged bed constructed wetland (VSB). In Europe the vertical VSB (called a trickling filter in the past) has again proved effective for small flow onsite treatment in rural communities. The various secondary filter systems are discussed below. Refinements in septic tank design to reduce suspended solids, and to pulse dose the secondary treatment filter bed, in order to extend the life of the bed and periodic maintenance are also discussed below. Cleaning and Operation of Septic Tanks: Small septic tanks are not particularly odorous and can be located close to buildings. If space permits, they can be located at a distance for convenience of removal of the sludge. Little attention is required for septic tanks, aside from inspections of the effluent. The tank requires cleaning when large amounts of septic sludge appear in the effluent. The solid matter that accumulates in the septic tank settles and is digested by the anaerobic bacteria, reducing the volume and changing the character of the sludge. This residue must be removed at intervals. Small septic tanks require cleaning only once in several years, while larger installations may require cleaning once or twice a year. Some tanks are made with hopper bottoms with a sludge pipe leading to the lowest point, so arranged that by opening a valve the difference in head between the level of the sewage and the outlet of the pipe will force the sludge out onto a drying bed. Sludge Drying Bed: The sludge drying bed is made up of a layer of cinders or fine gravel 6 or 8 inches thick and under-drained by means of drainage tile (opened-jointed tile pipe or perforated plastic). Most of the liquid seeps away through the gravel or cinders, and the sludge dries to a hard cake. Most small installations bury the sludge in a trench.

Siphon Chambers: Pulse dosing the secondary filter will enhance the lifetime of the filterbed, as well as the effectiveness of the filter bed. A smaller size filter bed may be designed for pulse dosing. The effluent from a siphon discharges automatically, and a rush of the effluent runs off through the outlet pipe into the secondary filter bed. The siphon chamber increases the efficiency of the filter bed. In subsurface irrigation the rush of sewage enters the soil and seeps off. Time is

allowed during refilling of the siphon chamber for the air supply to be renewed in the porous soil.

Note: a manhole for sludge cleanout must be included in the design. Sludge may also be emptied from a tank with a hopper bottom through a valve located at the bottom of the hopper, if enough head is available. Sludge from in-ground tanks is pumped from the top manhole. Imhoff Tanks: Named after the inventor, Karl Imhoff of Germany, the Imhoff tank is a variation of the septic tank. Two chambers are built into the tank. The upper chamber is the flow chamber through which the sewage passes at low velocity, the lower chamber is where anaerobic digestion takes place. The solids of the sewage settle to the bottom of the upper or flow chamber, which has sloping bottom walls. At the lowest point of the flow chamber is a slot through which the settled solids fall into the lower chamber. The slot is overlapped or trapped in such a way that the gases generated in the sludge chamber cannot enter the flow chamber. A gas vent, or scum chamber, is connected to the sludge chamber. The advantage of this type of tank is the more3 complete separation of the digesting sludge from the sewage, which means fewer suspended solids in the effluent. The fact that the sewage does not come into contact with the septic sludge keeps the flow chamber sewage from becoming septic (foul odor) itself. This has merit for above ground installations in flood prone areas. Keeping the sewage fresh with fewer solids facilitates secondary treatment (less clogging). The greater complication and construction cost has limited application in the past to facilities that serve over 25 people.

In large Imhoff tanks the capacity of the flow chamber is relatively small, from 2 to 3 hours flow. Because of large fluctuations in smaller installations, the retention period in the flow chamber is designed to be longer, 5 to 6 hours being considered safe. This should remove 50 to 60 per cent of the suspended solids from the sewage leaving only the very finest particles. The amount of sludge storage to be provided is important. For small sewage disposal plants this is generally 3 1/2 cubic feet per person contributing to the tank. The total depth required in small plants will usually be around 10 feet (3 meters). Scum boards are placed about 12 inches before inlet and outlet. The scum boards extend about 12 inches below the flow line and also act as baffles. The area of the gas vent should be at least 25 per cent of the area of the tank, and the slot connecting the flow and sludge chambers should be 5 inches wide and have a horizontal overlap of at least 4 inches.

Sludge removal from Imhoff tanks is usually through a vertical pipe through which the sludge is pumped, or a horizontal branch is placed 3 to 4 feet below the level of the sewage, allowing draw off of the sludge by the difference in hydrostatic head. The sludge produced is much the same as ordinary septic tanks, though somewhat better digested and denser. The sludge is disposed in the same manner as sludge from septic tanks. Secondary Treatment The septic tank treatments above remove a part of the suspended matter. The septic tank effluent has little or no dissolved oxygen. Imhoff tank effluent will be fresher, but if allowed to stand untreated it will also become black and septic (foul odor). Further treatment is required: secondary treatment uses digestion by aerobic bacteria (nitrification). Secondary treatment processes provide a porous material on which the active bacteria lodge and digest the sewage as it trickles over the filter material. Filtration can be cost-effectively accomplished by applying sewage (septic tank effluent) to soil, natural or artificial sand beds, or to beds of crushed stone. Subsurface Irrigation: In small flow installations (such as homes) the septic tank effluent is applied to the soil through perforated plastic pipe (or open jointed tile pipe) installed in trenches. The soil must be dry (above the water table) and porous, and the application field (leach field) must be large enough to absorb the daily load of effluent. Heavy clay soils are not suitable for leach fields.

Limestone formations should never be used, since solution channels may carry the effluent directly to a well. Knowing the percolation capacity of the soil is necessary to calculate the length of subsurface drainage pipeline required. A percolation test is used to determine the soil suitability for disposal, by measuring the perolation rate of water into soil in a standard-size hole. There are numerous health department formulas for determining the required length of drain in the leach field. For instance, with suitable soil percolation one-fifth to one-sixth of a foot of drainage tile per gallon of tank capacity would be used for septic privies and 9 inches of drainage tile line per gallon of septic tank capacity. On this basis for a septic tank the required length of drainfield line will be 25 to 40 feet of drain tile per person contributing (less for schools, see above for recommended school tank capacities). In soils with slow percolation rates more drainfield length will be required, in sand and gravel the length can be reduced. With the exception of sandy or gravellt soil the trench in which the drainfield pipe is laid is filled with coarse sand, broken stone, gravel, cinders, or coke so that the drain pipe is surrounded. This facilitates absorption by the soil. In order to prevent clogging of the drainlines by earth or fine sand, the tile pipe joints are protected with tarpaper or similar material. Since the bacterial activity is greatest near the soil surface, the drainfield pipe should not be buried to deep. The grade of the drainpipe must be carefully laid out. If too steep, the sewage will rush to the lower ends with poor distribution closer to the tank. The best distribution is obtained by a slope of 2 to 3 inches in 100 feet. The layout of the disposal pipe will depend on the shape and slope of the disposal field. Distribution boxes to branches may be used, since the effluent should have few suspended solids. Since the horizontal distance of percolation through soil will not ordinarily exceed 5 feet, the pipe branches can be spaced about ten feet apart. In certain soils with low percolation rate, underdrains may be placed at a sufficient depth below the effluent drainfield tile and between the drainfield lines. These drainage lines will prevent groundwater contaminationand also carry off the effluent after it has percolated through the soil (a variation of the sand filter or VSB). Underdrainage may be particularly useful or even necessary in clay soil. Trenches in which the drain tiles (or perforated plastic pipe) are placed should be filled with gravel in a manner similar to the trenches for the effluent drainfield. The disposal field should be plowed with a subsoil plow before installing the pipe system in clay soils.

Sand Filters: Other variations used for locations with unsuitable soils are sand or gravel filters, either in a pit in the ground or in a mound or box above grade. A sand filter designed to treat septic or Imhoff tank effluent should provide an area of 32 square feet per person. The filtering material is clean, coarse sand 30 to 36 inches deep and supported by 4 to 6 inches of graded gravel. The upper two inches of gravel should be 1/4 to 3/4 inch size to prevent the sand from working into the pore spaces in the gravel. The balance of the gravel should be 1 to 2 inches in size. The bottom of the bed should be gently sloped to underdrains which may be made of perforated plastic or open-jointed tile pipe surrounded by gravel. One 6-inch drain should be sufficient for a bed about 30 feet square. Lining the bed with concrete is not necessary except in very wet, soft soil. The sand filter area is divided into two units so that when clogging occurs one bed can be rested a week or more, and if necessary the upper layers of sand, and especially the organic mat which

forms on the surface, can be scraped off. Siphon dosing is advisable so that the bed may re-aerate between doses. The head required by a tank with sand filter beds is 5.5 to 6 feet. The sand filters are effective, but require the maintenance described above. The Mounded Leach Field Variation: In areas where groundwater levels are high, the leach field is elevated to ground level, and a layered mound of sand, gravel, rocks and soil is built above the field. Another advantage is greater dispersion over a more confined area. Some owners have turned their septic mounds into attractive flower and rock gardens. A typical mound leach field is shown below.

Source: Homeowner's Complete Guide to Plumbing, Merle Henkenius, 1989

Vegetated Submerged Bed Wetland (VSB): Another variation of secondary filtration is the vegetated submerged bed wetland (VSB), a rectangular pit filled with gravel through which the effluent flows. A VSB is not an actual wetland because it does not have hydric soils. Wetland vegetation is planted on top of the gravel in the VSB, however, the vegetation's role in treatment is moot, since the majority of flow is below the root zone. Data suggests these systems work as well without plants as with them. The avoidance of surfacing of the effluent is a major design criterion, and high amounts of precipitation can increase the design flow of a VSB. The system is shallow and has sufficiently sized gravel to permit long-term subsurface flow without clogging. The main advantage of a VSB over a free water surface constructed wetland for waste treatment is the isolation of wastewater from vectors, animals and humans in the VSB. Concerns with pathogen transmission and mosquitoes are greatly reduced with a VSB system. Properly designed VSB systems may not need to be fenced off or otherwise isolated from people and animals. The free water surface constructed wetland (FWS) presents problems with mosquitoes, other vectors and human access, and will not be considered here. The vast majority of VSB systems have used horizontal flow, but several systems in Europe have used vertical flow. In the last five years several unsaturated vertical flow systems have been constructed and tested in Europe. They have been used for treatment of septic tank and other effluents. They appear to perform significantly better than conventional VSB systems, with recommended design loadings twice that of conventional VSB systems.

Source: Constructed Wetlands Treatment of Municipal Wastewaters, EPA/625/R-99/010, September, 2000

Gravity-Flow Trickling Filter: Re-invented as the "vertical flow VSB," the trickling filter is a secondary treatment method in which the sewage is allowed to flow intermittently through a bed of crushed stone, coke, lath or brush. Modern non-woven proprietary textiles have improved the performance of this type of filter many fold; however, the various media mention will also work. The purpose of the filter media is to supply as much surface area as possible for attachment (or capture) of a film of aerobic microbiota. The effectiveness of the filter media is proportional to the surface area made available. Plastic cuttings and various other inert materials have been used for filter media. Trickling filters have also been constructed of brush, cleaned of leaves, and tightly bound in bundles. The buyndles are laid in successive layers 8 to 10 inches thick, each layer being at right angles to the next. As the thin film of sewage trickles down over the filtering material it is oxidized by the bacteria living in the organic coating which covers the surfaces of the filter media. The effluent is stable but may contain considerable suspended matter, due partially to sloughing of the aerobic biofilm. The suspended matter may be removed by final sedimentation. For small installations, good results have been reported for lath filters, built up of ordinary laths placed in successive layers, placed at right angles to the next course. Each lath is centered over the opening left between the laths below. The laths are spaced 3 inches apart in each course. The volume of the bed should be about 8 cubic feet per capita, and the depth should not be less than 3.5 and preferably 5 feet. Provision should be made for the entrance of air into the bed. Distribution of sewage onto the filterbed can be by means of a tipping bucket, that when full tips its contents into small distributing channels on the filter surface. A small Imhoff tank can be used to remove the suspended solids from the final effluent. Imhoff tanks for this purpose should have a capacity in the flow chamber of 2 hours for a plant serving 25 people or less, and 1 hour for larger plants. A sludge capacity of 2 cubic feet per capita should be included in the final Imhoff tank.

The disadvantage cited for trickling filters is the head needed; however, this could be used to advantage in an installation built on stilts above flood level. Not less than 7 feet of fall are required. There is also a possibility of flies being drawn to the filter. There is much literature on control of trickling filter flies. At times odors may also be present. Overall, the trickling filter is one of the most viable secondary treatment systems for use in seasonally flooded areas, since it can be elevated (along with an Imhoff tank) and the gravity head is available in toilet installations built on stilts above the design flood.

Imhoff tank and lath trickling filter for 10 people. Inlet sewer upper left corner. Smaller second Imhoff tank for effluent

polishing lower right.

4.5 Recommended Site Screening

MOE shall develop a procedure for screening sites for potential wastewater disposal problems, that is, slow percolating soils, seasonal lack of water supply, and seasonal flooding.

Identify existing sources (if any) for hydrologic information that can be used to predict level and duration of flooding and to evaluate groundwater resource availability.

Using the screening system developed above, list the appropriate alternative system(s) according to problem area. For example, list the sanitary systems that would be applicable to identified BEIC project flood-prone areas, areas with high water tables, and sites with soils with slow percolation (clays). Testing Soil for Absorption (Percolation Test): Soils vary widely from region to region, and even from one site to another. The test for soil percolation properties is simple. Dig about 4 to 5 evenly spaced holes about 30 inches deep in the proposed leach field area of the site. Take care not to glaze the sides of the hole. Fill each hole half full of water and ideally let stand for 24 hours. This will more accurately simulate actual system use. On the following day place nails into the sidewalls of each hole 10 inches from the bottom. Note the exact time and pour water into the holes up to the level of the nail markers. In exactly one hour, measure the distance from the nail to the remaining water level. The difference between the two water levels gives the per-hour soil absorption rate. Log the data. Continue to check the absorption each hour for five consecutive hours. If all water drains away before the five hours is up, log that time. As a rough indicator, if the soil absorbed less than an inch an hour, a conventional leach field is not practical.

Source: Homeowner's Complete Guide to Plumbing, Merle Henkenius, 1989

4.6 Treatment Selection Recommendations:

The plumbing mistakes in current designs should be rectified.

Water supply pumps and toilet facilities should be elevated above flood design level, as currently practiced, and would be more usable if attached to the school platform.

A program of water supply testing with inexpensive field tests for E. coli and a method of well chlorination should be initiated.

Maximum use should be made of water supply storage.

Septic tank effluent should receive secondary treatment prior to release into the environment.

There are a variety of secondary treatment options, some are appropriate to high groundwater levels or restricted space.

The Imhoff tank/trickling filter/Imhoff tank polishing unit shown above can be built as a self-contained gravity flow system that can be elevated above design flood, and this system benefits from the head (vertical height) available. With more modern filter media, such as non-woven textile scraps, these units can be made relatively small and efficient.

Alternatives for non-water carriage sanitation are detailed in this paper, including the "septic toilet."

A site screening process to determine the best system for school size, land availability, and environmental conditions, such as flooding and soil percolation, should be initiated for all proposed project sites. The appropriate technology should be matched to the specific project and site.

5. References

Constructed Wetlands Treatment of Municipal Wastewaters, EPA Manual, EPA/625/R-99/010, September, 2000. Homeowner's Complete Guide to Plumbing, Merle Henkenius, Popular Science Publications, Sedgewood Press, New York, 1989. Leverenz Harold, P.E., L Ruppe, P.E., G. Tchobanoglous, Ph.D, P.E., J. Darby, Ph.D., P.E.: Evaluation of High-Porosity Medium in Intermittently Dosed, Multi-pass Packed Bed Filters for the Treatment of Wastewater, in Small Flows Quarterly, Spring 2001, Vol. 2 No. 2. Maber, Steve, personal files from: World Bank Water and Sanitation Project, Honduras, 2004. Municipal and Rural Sanitation, Third Edition, Victor Ehlers, C.E., and Ernest W. Steel, C.E., McGraw-Hill, New York, 1943. National Small Flows Clearinghouse, products listing, http://www.nesc.wvu.edu/nsfc/nsfc_index.htm Price, Michael S. Improving the Performance of Soil Based Receiving Environments Using Flow Equalization, Effluent Filtration and Solids Retention, in Proceedings, NOWRA 2001 10th Annual Conference and Exhibit, October, 2001. W. J. Shoupp, Dingess, J. M. Moe, P. G., Microbial Purification of Recycled Wastewater in a Closed System, Water Research Institute, West Virginia University, Information Report 15, 1981.

The Pour-Flash Latrine (Honduras)

6. ANNEXES

ANNEX 1. Environmental and Social Safeguards Checklist

ENVIRONMENTAL SCREENING FORMAT School and Sanitary facilities Construction

Instructions: This form has to be filled by local authorities or school committee

I. General Information 1. Name of village, commune and province

2. Name of proposed scheme

3. Type of scheme New construction □

Reconstruction □

Rehabilitation □ Other (please specify) □

4. Objective of the proposed scheme and brief description

Please check ( √ )

5. Does the proposed scheme involve all types and classes of the people in the locality? □ □ □

II. Environmental Checklist (please check the box where appropriate)

1. Does the scheme located in the land mine or UXO area? □ □ □

2. Is there any cultural heritage area nearby the propose scheme? □ □ □

3. Does the scheme’s implementation interrupt the natural flow of river, canal or any stream? □ □ □

4. Does the scheme’s implementation increase the possibility of ground water pollution? □ □ □

5. Does the scheme’s implementation increase the possibility of surface water pollution? □ □ □

6. Does the scheme generate any waste? □ □ □ 7. Is there any waste management plan for the scheme if it generates waste? □ □ □ 8. Is there any chance of increased public health problem by throwing waste into open water bodies? □ □ □

Instructions: This form has to be filled by local authorities or school committee

9. For construction of school buildings, is there any chance of creating problems to water bodies that are used for irrigation or other community purposes? □ □ □ 10. Does the scheme generate air and dust pollution? □ □ □ 11. Does the school construction generate noise or disturbance? □ □ □

12. For the sanitary latrine construction, is there any drinking water source within 30m distance of the latrine? □ □ □ 13. Is there any chance of trees to be cut down by the implementation of the proposed scheme? (If yes, then please specify the number of trees to be cut down) □ □ □ 14. Is there any chance of destruction of biodiversity (fish, birds, and animals) habitat by the implementation of the scheme? □ □ □ 15. Mitigation measures:

III. Other Information (if any)

IV. Evaluation by Environmental Safeguards Specialist

Is the form filled correctly? Yes □ No □

Are the proposed mitigation measures satisfactory? Yes □ No □

If the mitigation measures are not satisfactory, why? Any recommendations for improvement? (where necessary):

Name of Environmental Safeguards Specialist

Signature

Date

ANNEX 2. Environmental Codes of Practice (ECOPs)

ENVIRONMENTAL CODES OF PRACTICE (ECoP)

FOR CONSTRUCTION SITES Introduction The Environmental Codes of Practice (ECoP) for construction sites of the proposed Cambodia Global Partnership for Education Second Education Sector Support Project is prepared in order to help developers and contractors working in Cambodia to understand what standards should normally be adopted when undertaking the following types of construction works:

a. Demolition b. Site clearance and preparation c. Construction d. Maintenance and repair

It is the responsibility of the main contractor to ensure that all sub-contractors and site personnel are aware of and comply with the requirements of the ECoP. 1. Legal Framework Whilst compliance with the ECoP is voluntary, it should be avoided to use statutory notices for the enforcement action. However, whenever the ECoP has been incorporated into a bidding document as part of the contract agreement, failure to comply with its requirements could result in enforcement action under Cambodia law. 2. Community Relations Past experiences of construction works within community/village area clearly demonstrated the benefit of warning residents and commercial operators in advance of the disruption that may arise. It is important to ensure that contractors who are intending to undertake construction works:

1. Establish a local point of contact for any enquiries and/or complaints relating to the construction works; and

2. Nominate a staff member who will liaise (as necessary) with MoEYS, residents, construction school committee and commercial operators (if any).

In addition, the main contractor should display details of its name, address and telephone number, together with an indication of the expected duration of the works at the prominent position on the site boundary. 3. Working Hours It is important that the following working hours should apply when there are sensitive receptors (e.g. school, hospital, pagoda/temple, residential property) next to the construction site. 08:00 – 18:00 (Monday-Friday) 08:00 – 12:00 (Saturday-Sunday)

Unless agreed in advance with MoEYS, no construction activities should be undertaken on a Public Holiday. MoEYS can also acknowledge that some activities may be undertaken on site without causing disturbance to neighbors (e.g. electrical rewiring, painting), and therefore works may be scheduled outside the normal working hours. Prior notice of such works and schedules should be given to the Environmental Safeguards Specialist of MoEYS. 4. Child Labor Is Not Accepted (Refer to ILO Conventions 138 and 182 and to the UN Convention on the Rights of the Child.) According to the UN Convention on the Rights of the Child, a person is a child until the age of 18. Child labor is not allowed in the construction site. No person shall be employed at an age younger than 15, or younger than the legal age for employment. The contractors must take the necessary preventive measures to ensure that they do not employ anyone below the legal working age. 5. Security and Safety Fence Construction sites should be fully enclosed to protect the general public, teachers, and pupil from entering. The safety temporary fence should be appropriately built for such purpose. 6. Access Gates and Scaffolding Access to and from the site should be organized to allow vehicles to enter and leave the site in a forward gear. When necessary, a gate keeper should be employed to ensure the safety of pedestrians walking on the public walkways around the construction site. Scaffolding that encroach onto the public road will require the Environmental Safeguards Specialist’ approval prior to installation. 7. Lighting The contractors should ensure that any lighting of the site and its perimeter is sufficient to ensure the safety of pedestrians. In addition, the lighting should be located and orientated so that it does not cause intrusion to adjacent residential property or distract passing motorists. 8. Access Road Management Where reasonably practicable all loading and unloading of contractors’ vehicles should be within the site boundary. Deliveries and collections should be scheduled to coincide with the normal working hours. Contractors should avoid parking vehicles on the public access road. Any damage to the pavement, kerbs or other public assets that is attributable to the site works should be repaired to the satisfaction of property owners. 9. Mud on the Road Hard-standing or equivalent compacted areas should be provided on site for vehicle parking and adjacent to access points. A wheel washing facility should be provided to minimize the deposit of mud onto public road. 10. Environmental Control

10.1 Dust Although a high standard of general site housekeeping will minimize dust emissions, the following steps should assist:

1. Bulk storage of potentially dusty materials should be located away from the site boundary. 2. Mixing large quantities of concrete on site should be undertaken using enclosed plant. 3. Cutting and grinding operations should be undertaken using appropriate dust suppression

techniques. 4. Potentially dusty spoil and other waste materials should be damped down regularly when

handled and transported in sheeted vehicles. 5. Rubble-chutes should be used with care and drop heights kept to a minimum.

10.2 Construction Waste Management Much building/construction waste is made up of materials such as bricks, concrete and wood damaged or unused for various reasons during construction. Responsible management of waste is an essential aspect of sustainable development. Hence contractors/builders are requested to:

1. Properly dispose waste in a safe place and waste separation should be applied for organic, liquid, battery and chemical by on-site sorting and stored in appropriate containers;

2. Properly collect all waste generated within the site and dispose by licensed collectors (if there is in the area);

3. Re-use and recycle, whenever possible i.e. excavated material, bricks in order to minimize the waste;

4. Burning of waste should be avoided, especially for plastic waste which is widely used in Cambodia.

10.3 Air Pollution Smoke, fumes and particulate emissions can be minimized by ensuring that:

1. No on-site bonfires are used for the disposal of any waste. 2. All plants are properly maintained and throttled down or switched off when not in use. 3. Fuel storage tanks are located away from the site boundary and vented at a point remote

from sensitive receptors (e.g. school, hospital, pagoda or residential property). 10.4 Land Contamination In some cases the remediation of known or suspected land contamination may require the excavation and disposal of soils and other waste materials. Such materials should be adequately segregated and removed to a suitably licensed facility in accordance with article 13 and article 16 of Sub-decree on Solid Waste Management (No. 36 ANRK.BK, April 1999). If there is likely to be an offensive odour or vapour associated with the excavation and disposal operation the local authorities should be advised in advance. 10.5 Asbestos Works involving the treatment or removal of asbestos products should be undertaken by a licensed contractor and handled in accordance with hazardous waste management of Solid Waste Management Sub-decree, 1999, of the Ministry of Environment. See further in ESMF Section 3.3.

10.6 Noise and Vibration The contractors should take necessary measures to minimize noise and vibration impacts to nearby community. Noise from the proposed construction works should comply with article 7 of Sub-decree of Air Pollution Control and Noise Disturbance (July 2000) of Ministry of Environment. The contractors have to use the best practicable means to minimize noise for example:

1. All plants and equipment should be selected having regard to its published sound power level.

2. If an activity is inherently noisy (e.g. cutting steel bars or mixing concrete) then an alternative technique should be investigated.

3. Effective silencers and acoustic covers should be provided and maintained in good working order.

4. Plant and equipment should be located having regard to its proximity to sensitive receptors (e.g. existing classroom/school, hospital, library, kindergarten and residential property).

5. Temporary structures and buildings may provide useful noise screening. 6. Fixed items of plant (e.g. generators) should be electrically powered rather than diesel or

petrol driven. 7. Sufficient time should be allocated for large concrete pours. 8. Anti-social behaviors involving swearing, shouting and loud radios should be avoided.

10.7 Water and Effluent Water and effluent generated from on-site activities should be treated and disposed of in accordance with the provisions on waste and hazardous discharge of the Sub-decree on Water Pollution Control, April 1999 of Ministry of Environment. Adequate pollution prevention techniques should be adopted to ensure that any potentially hazardous substances do not come into contact with vulnerable water (e.g. via surface water drainage systems). Recycling water should be encouraged. 10.8 Pest Control Preventive measures should be adopted to control any rodent activity on site and test baiting may be necessary to confirm the existence or otherwise of an infestation. All redundant drainage and sewerage infrastructure should be improved or stopped up and accumulations of putrescible waste should be avoided. 11. Provision for chance finds procedure Chance finds are defined as physical cultural resources encountered unexpectedly during project implementation. If this case occurred during construction, the borrower is obliged to prepare measures for chance finds which is acceptable to the Bank.

ANNEX 3. Environmental Assessment Field Visit Report

ENVIRONMENTAL ASSESSMENT ON CAMBODIA GLOBAL PARTNERSHIP FOR EDUCTION SECOND

EDUCATION SUPPORT PROJECT

A. Background and Objectives The global commitments to the Millennium Development Goals (MDG’s) and Education for All (EFA) are promoting major investments in school construction and rehabilitation around the world. Cambodia, in efforts to reduce poverty and increase prosperity, has recognized the key importance of education to its national development; and now is preparing the Cambodia Global Partnership for Education Second Education Support Project to be financed by the Global Partnership for Education (GPE) which the World Bank administers. The project objective is to assist the Government of Cambodia to expand access to ECE (Early Childhood Education) for 3-5 year olds and improve access to and quality of basic education for students, particularly those from disadvantaged background. One of the project components involve civil works, the construction of ECE facilities within community areas. There are likely to be some concerns relating to environment and safety during construction. To assess environmental issues that may derive from civil works, field visit to different school constructions (completed under EFA-FTI-Project) was prepared. The objectives of this field visit are to:

1. Visit ECE classrooms construction buildings and reassess overall environmental conditions and potential impacts that may arise during construction

2. Assess the school committee awareness in relation to EMP implementation 3. Understand the role and responsibility of local authority/school committee with regards to

environmental mitigation measures which include the solutions or what the contractor must do during construction (EMP)

4. Improve existing EMP and other tools if required

B. Methodology First field visit to school construction (completed under EFA-FTI Project) was conducted on 15 March 20013 to Kampot province and second field trip was from 18-20 March 2013 to Kampong Thom and Banteay Meanchey provinces. Two school constructions of each province are selected and proposed by the Department of Construction of MoEYS. Prior to field visit an initial meeting was made with World Bank-Cambodia office to understand the purpose and objectives of the assignment. Discussion was also made with the Director and staffs of Department of Construction of Ministry of Education, Youth and Sport to (a) understand environmental related issues during project implementation and suggestions for better improvement; (b) select school for lessons learn field visit. At each visited site, school principle and school support committee members were invited to a meeting to discuss environmental related issues (noise, dust, solid waste, safety, site management, sanitation facilities, surrounding environment, etc.) during school construction. They are also consulted for their opinions and suggestions for better project implementation in terms of

environmental safeguard. Students in the school were also consulted with regards to the use of facilities.

C. Field Findings All of school constructions are located in residential area where it is generally not associated with any major environmental concerns. Through consultation with school committee during field visit, the construction issues related to the project were identified as follows: Sanitation Facilities Sanitation facility/ toilet have a soak away system which is good and appropriate practice in rural area of Cambodia. However, water stagnant in the toilet entrance is a health concern for pupil. It is observed that a small water spillway, in the toilet entrance, is covered with dust/soil. During School Construction In general, the discussion with relevant stakeholders revealed that the construction of school and school facilities did not result in adverse environmental impacts including air, noise, etc. The EMP was implemented on the ground by the contractors and supervised by site engineers of MOYES. Existing EMP which was used for FTI is a well drafted document, and can be applied for construction of facilities under GPE. Minor improvement is made on existing EMP (see updated EMP enclosed). The team prepared an ECOPs which is trusted to be simpler and practical for safeguarding the construction of facilities. An environmental checklist was also drafted for school committee, site engineers, and other relevant stakeholders for site selection and for monitoring the implementation of EMP/ECOPs during construction. These documents are to be included in the bidding documents to inform contractors their responsibility to implement EMP and other safeguard documents. However, the rapid environmental assessment noticed some minor issues to be considered as below:

1. Workers’ Sanitation: Most of the school visited, workers used school toilet together with pupil and teacher.

2. Waste Generation: Impact on surrounding areas if not disposed of properly. But it is noted that in all visited sites the contractor managed to put it in a small disposal area within school compound.

3. Environmental Mitigation Plan: The EMP notice was to install at public places within school premise. But it has not much been the case according to the discussion. School committee did not pay much attention 9 to read and understand the content of the notice. When question if they were participated in construction and environmental training session, school committee confirmed their participation in a one day training organized by Department of Education, Youth and Sports in the province. And the training is very much focus on construction technical specification rather than focusing on environmental safeguard and safety. However, the committee did not check if all mitigation measures in the notice paper are complied by contractor during construction.

4. One of the pupil during consultation reported that he was injured in his foot by construction nail (school construction in Kampong Thom province). Hence the risk of accidents and injuries requires that various preventive measures are taken.

9 Most of School Construction Committee consulted has seen the notice but do not read and do not know what the

contents of the notice are.

5. School committee is still not fully well aware of environmental related issues during construction. Thus EMP was regarded less important. Attention should be paid and training session of MoEYS should allocate time for safeguard rather than put together in same session of technical specification.

D. Recommendations

Environment construction related issues awareness and site safety should be well trained to local school committee who is responsible for daily site supervision. Only one day training session is not enough to cover both construction supervision and environmental related issues. It is recommended that apart from training session given to school committee on technical specifications and site supervision, more attention should be paid to safeguards.

EMP implementation: The contractor/site engineers should be well aware of the contents of EMP which is included in bidding document and should be enforced/monitored by school committee.

A meeting between site supervisor and school committee more often during every his/her site visit to discuss, share, explain or follow up construction activities.

The consultation with local school committee shown that there is a lack of environmental specialist during construction. The site engineer is very much focus on technical issues rather than environmental issues. It is recommended that an environmental safeguard specialist should involve in every school construction. Together with site engineer, environmental safeguard specialist should provide a refreshment training on site safety, supervision and environmental safeguard issues.

APPENDIX: Schedule for Field Visit

Date Departure

Time

Province District Primary School

15.03.2013 6:00 AM Kampot - Dang Tung

- Damnak Chang

aeur

1. Reaksmey Udom

2. Phnom Tauch Thlok Phlong

18.03.2013 6:30 AM Kampong

Thom

- Kampong Thom

- Staung

1. Krachap (instead of Darey Slap,

since appointment cannot be made)

2. Kunthean

19.03.2013 6:00 AM Banteay

Meanchey

- Poipet

- Thmar Puork

1. Reaksmey Serei Pheap

2. Samaki Chrork

20.03.2013 7:30 AM Travel back to Phnom Penh