CHAPTER 5

Evaluation of remedial measures

Table of Contents of Chapter 5 5 EVALUATION OF REMEDIAL MEASURES ................................................................................................... 1

5.1 REVIEW OF SCENARIOS AND REMEDIAL OPTIONS................................................................................................. 1 5.2 EVALUATION OF REMEDIAL OPTIONS .................................................................................................................. 2

5.2.1 Do nothing.................................................................................................................................................. 2 5.2.2 In situ stabilisation of Tailing 3 (Chap. 4.3 and 4.4).................................................................................. 3 5.2.3 Transfer of tailings to a safer site (Chapter 4.5) ....................................................................................... 4 5.2.4 Landslide Stabilisation ............................................................................................................................... 6 5.2.5 Solutions to avoid River Blockage (Mailuu Suu river diversion tunnel or river-channelling) ................... 7 5.2.6 Proposed option: phased approach considering a combination of techniques .......................................... 9 5.2.7 Protection measures for drinking water supply........................................................................................ 13

5.3 DECISION MAKING............................................................................................................................................ 13 5.4 PROPOSED FUTURE WORK ................................................................................................................................ 19 5.5 INFORMATION EXCHANGE, COMMUNICATION OF PROJECT RESULTS TO POPULATION, DECISION-TAKERS, STAKEHOLDERS AND INCLUSION OF STAKEHOLDERS IN DISCUSSION ....................................................................... 22

5.5.1 Communication of project results/Building population trust ................................................................... 22 5.5.2 Working Groups ....................................................................................................................................... 23

5 Evaluation of remedial measures

5.1 Review of scenarios and remedial options The area of the town of Mailuu Suu and downstream villages is threatened by a potential radioactive pollution from radioactive substances stored in 23 tailings and 13 mine waste dumps some situated along the Mailuu Suu River of which the stability is sometimes at risk.

Major landslides potentially affect directly or indirectly uranium ore processing tailings deposited along the Mailuu Suu River valley (i.e. tailings deposits No. 3, 9, 10, 8, 5 and 7).

It could be concluded from the radiological assessment that, except for the special case of Kara Agach, that the dose to the habitants of Mailuu Suu and villages downstream the tailings is of no radiological concern. Even the amount of radionuclides leaching from Tailing 3 will not add significantly to the radiation dose.

However, given the limited stability of Tailing 3, a dam break may occur even with a slight impact, provoked by a an earthquake, even of low activity, additional deposits close to the present dam build on the tailing surface or increased water content in the tailing. Such dam break may result that part of the tailing content is taken to the Mailuu Suu River and radionuclide levels in the water will be above the limits for drinking water.

Even more serious scenarios can be envisaged: The accidental and catastrophic scenarios imply the following sequence of events (also see Chapter 4.2):

a) Major landslide or mudflow triggered by heavy rainfalls (eventually coinciding with seismic events during a period of high river discharge and or eventually impacting tailings in the Mailuu Suu river valley).

b) Full river blockage by the resulting landslide or mudflow.

c) Rapid formation of a lake behind the blockage with backwater effect leading to two consequences:

- Flooding of the base of upstream uranium tailings,

- Flooding of the various houses and settlements at low elevation along the river banks upstream of the blockage.

d) Over spilling of water above the obstruction and/or sudden rupture of the natural dam.

e) Resulting violent mud flow with three potential major effects:

- Partial or total destruction of some of the downstream tailings

- Partial erosion and destabilisation of the base of the upstream tailings in the wake of this mudflow due to wave and flow velocity,

- Flooding of the low areas of the Mailuu Suu town and downstream settlements beyond Mailuu Suu. This mudflow may contain, disperse and deposit various amounts of radioactive residues (tailings or mine wastes) which have been destabilised and picked up by the flood waters.

Within the framework of a critical analysis it must be realised that the various historically observed river blockages by landslides do confirm that river obstruction is a sheer reality and not a hypothetical working assumption. Therefore, the so-called accidental scenario has a non-negligible probability of occurrence. The only debatable point is the volume and height of the river obstruction and the stability of this obstruction with time.

Also it must be realised that the river blockage itself, independently of the presence of the tailings, is a real hazard for the Mailuu Suu town.

Chapter 5 page 1

Obviously considerable costs are involved in order to achieve a sustainable solution to the problems in Mailuu Suu. By addressing the tailings problem exclusively, the landslide problem remains and vice versa.

Options that could increase the safety against destructive slope movements and eventually related failure of unstable tailings impoundments must simultaneously incorporate elements of health- and environmental protection.

Considering in addition of the above, the economic aspect, comprehensive investigation programs and a detailed feasibility study are compulsory to select the preferred remedial option or approach.

The options considered under this project are summarized as follows:

1. Do nothing (remaining status quo with minimal control)

2. In situ stabilisation of tailings

3. Transfer of tailings at risk to a safer site

4. Action to stabilize slope-movements and –instabilities (expected limited feasibility)

5. Solutions to avoid river blockage a) river diversion tunnel b) river channelling.

6. A combination of remedial options and a phased approach: stabilise tailings at risk (short term-mid term) and continue feasibility assessment of two selected (preferable) options until a final decision can be taken, a design can be made for the preferred remedial action or combination of actions.

Option 6 would include:

- Improve and/or stabilise tailing deposits (and mine waste dumps) in situ in the short and medium long term

- Continue feasibility assessment on the transfer option 2 starting with T3 and simultaneously on option 5 under technical feasibility-, public and environmental health, economic and public acceptance considerations until reaching a decision.

- Improve and continue geo-technical, environmental and radiological monitoring and emergency preparedness. Transfer of population out of danger zones and relocation of endangered population.

Activities under 2, and continuing feasibility assessment- and (projecting)-work for options 3, and 5 to be incorporated and correlated in a multi-phased and time-“telescoping” approach as follows:

- in the short term – a) , c) and simultaneously proceed with b)

- mid term – decision on the basis of b) and complete evaluation of the feasibility of the preferred option. Secure the financing.

- mid to long term – design and finally execution of the preferred option.

Option 6 may lead to a full remediation approach if considered optimal and could lead to a complete dealing with both the tailing and landslide problem.

5.2 Evaluation of remedial options

5.2.1 Do nothing

The radiological assessments showed that the actual radiological exposure dose to the inhabitants of Mailuu Suu and villages located downstream the tailings is of no immediate radiological

Chapter 5 page 2

concern. The radiological situation at Kara Agach is of some concern. Following the present predictions, the amount of radionuclides leaching from Tailing 3 (and other tailings) will not add significantly to the radiation dose.

However, since dealing with a uranium mining and milling site, even the 'do nothing' option requires minimal action: maintenance of actual (be it not always appropriate) conditions of the tailings, maintenance of water diversion canals, fencing of the tailings or putting on warning signs, continuous monitoring to evaluate if situation is stable or aggravating.

The ‘do nothing’ option also entails an important risk. In case an accident would happen, this may entail a considerable increase in the radiological exposures (above 10 mSv/y) and may have important social (anxiety; disagreement with management of situation by responsible authorities), economic (decreased crop production, decreased value of land, unable to sell contaminated or suspected crops and food) and political (if contamination of Uzbek territory). The ‘costs’ of these potential consequences are difficult to estimate.

For the Consortium the ‘do-nothing-option is not an acceptable remediation option because of the likelihood that an accident would occur in the short-, mid-, or long-term with serious radiological consequences and justified related concern of the involved population. The radiological consequences of an accident may even result in transborder problems.

5.2.2 In situ stabilisation of Tailing 3 (Chap. 4.3 and 4.4)

Actual stability of Tailing 3

Stability calculations of GESTER for various options using the TALREN-programme led to the conclusion that the actual stability of the tailings pond is low. Overloads or surcharges (additional material induced by hill erosion or landslides) accumulating on the top platform or beach area generally have a limited unfavourable effect. However, when deposits are located close to the existing small (secondary) dam, tailing stability is jeopardised.

These calculations demonstrate that that the transfer of sediment load (and of the secondary dam) from this (central) area about 30m further uphill to the East has a positive (stabilizing) effect.

The new dam (2m high) will stop the erosion deposits originating from the slope above and an additional gutter along the dam will redirect the runoff waters towards the concrete gutter located at the south-west angle. A cover will limit water infiltration.

Also an additional embankment (cover or infill) located on the lower part of the downhill embankment of the tailing would have an extremely positive effect according to the GESTER calculations. On the other hand, an additional infill located on the upper part of the downhill embankment would have an extremely negative effect. A total cover should therefore not be applied on the entire downhill embankment but only on the bottom.

Very short term remedial measures

Accordingly reshaping and covering of the impoundment was therefore proposed by GESTER in the short term. These works can be rapidly executed using the logistics available regionally.

At the end of these first works, after erosion or the landslides have added an extra layer above the embankment, the safety coefficient F becomes, for a 15 meter wide bottom embankment:

- In the absence of an earthquake: F = 1,33 (compared to the initial 0.96)

- During an earthquake creating a pseudostatic horizontal thrusts γH = 0,1g and pseudostatic vertical thrusts γV = 0,05g : F = 0,87

- During an earthquake creating pseudostatic horizontal thrusts γH = 0,2g and pseudostatic vertical thrusts γV = 0,1g : F = 0,63

Chapter 5 page 3

Mid term remedial measures

Hence, GESTER concludes that in the mid term an additional stabilisation is necessary for important earthquakes.

The creation of reinforcements using the COLMIX columns (incorporation of cement and lime by mixing using a triple bore) strengthened by metallic girders will considerably help increase the stability.

At the end of these two first work stages, the safety coefficient in relation to a triple column density of 1 for 10 m², strengthened by 3 steel sections HEB 200, becomes for a 15 meter wide bottom embankment:

- In the absence of an earthquake: F = 1.33

- During the earthquake’s pseudostatic acceleration γH = 0,1g and γV = 0,05g : F = 0,96

- During the earthquake’s pseudostatic acceleration γH = 0,2g and γV = 0,1g : F = 0,67

It is thus assessed by GESTER that with one triple column per 10 m², an earthquake of a pseudostatic horizontal acceleration of 0.1 g will not jeopardize tailing stability.

The expected cost of the COLMIX method is estimated by GESTER with approximately 2,13 Mio Euro. All costs were estimated from prices before taxes applied in 2002 in western countries, by companies working according to western standards and using suitable materials. Cost for dealing with radiation protection and control issues during the works are estimated at an additional 0.2 Mio Euro.

According to the intensity of the earthquakes which should be taken into account, the tightness of the column grid should be more or less modified. As technical and economic improvement, GESTER suggests to choose a density of 1 triple column every 7 m², strengthened by 3 steel sections HEB 100. Instead of treated and strengthened COLMIX columns, another solution with vibrated ballast columns could be analysed in order to avoid residues liquefaction.

Drainage of excess pore-waters inside the bulk of the “pulpa” could eventually improve its resistance, but the tailing granulometry does not allow. There were cases were drainiage of fines was performed (WISMUT tailings) by applying surface pressure on the tailings and extruding the water through vertical wicks. However, the limited stability of tailing 3 does not allow for increased surface pressure. Maybe drainage by electro-osmosis would work but earlier tests by Russians failed (personal communication Geopribor). Detailed preliminary studies are required to test the feasibility of this option.

Hydraulic modelling for T3 suggested no significant decreased leaching from T3 to the Mailuu Su River.

5.2.3 Transfer of tailings to a safer site (Chapter 4.5)

It is understood that an earthquake has a direct adverse effect on tailing stability. Even the COLMIX improved tailings will fail in case of earthquakes with moderately high activity.

The second possible adverse effect is that of a landslide or of soil creep accumulations from the escarpment cliffs east and above T3, which would create an overload or surcharge on the tailing and could provoke dam rupture. A concomitant effect, is the risk of a liquefaction of the residues which are water-saturated, due to constant water influx or infiltration.

Therefore, and for the long term the alternative option of transferring T3 and other tailings depositories to a safer site has to be discussed and was investigated further .

It must be understood that the complexity of a tailings transfer with all the long term warranties, or the difficulty in extracting the radioactive residues most probably in form of a paste or mud

Chapter 5 page 4

(“pulpa”) should not be underestimated. Transport conditions around the northern city limits of Mailuu Suu must be adapted to this task, be safe enough and include appropriate measures for (radio)-protection of the population and workforce. Water treatment capacity must be installed and operate for several years. The selected alternative site must be thoroughly investigated and prepared and constructed along the guidelines of a disposal cell concept.

Hence, such relocation can not be accomplished before several years, since detailed pilot studies of the new tailings disposal site and a full fledged feasibility study still have to be prepared. Moreover it has to be realised that on top of providing appropriate transport conditions and important investment funds, adequate technologies, machinery, materials and personnel are still not yet fully available in Kyrgyzstan.

Under these circumstances it is important to start with the necessary short term stabilisation measures immediately or as soon as possible regardless of the outcome of the feasibility study and the final decision.

After pre-screening several sites proposed by Kyrgyzstan authorities, the location of Tailing 15 was selected for preliminary investigations including drilling a number of boreholes and examining the borehole samples. The ~15-km road is actually in poor condition. The advantages of this site are that transport does not pass through the city of Mailuu Suu or through other populated areas and that the site has sufficient free space next to tailing 15 to store tailing 3 plus additional residues. The disadvantage is access to tailing 15: the road must be improved if not reconstructed entirely.. It was decided jointly with Kyrgyzstan authorities that if waste from tailing 3 is to be transferred, the new depository will be built alongside tailing 15.

According to an assessment by GESTER (Chapter 4.5), the new storage site or depository for tailings T3 will be located in a depression next to tailing No. 15. It will be excavated in the upstream side of the valley and will be surrounded by dykes downstream. Other deposits could subsequently be transferred to the No. 15 site, e.g. T 7. In this case, the thick loess cover of and the already deposited tailings T15 will have to be excavated and temporarily stored in another area nearby. These deposits will be separated in hydraulically independent compartments by small dykes installed at the bottom. Several cells will have to be constructed at the disposal site. The bottom and sides of each cell and of the entire impoundment will have to be sealed in accordance with the so-called disposal cell concept and equipped with a proper cover design used in the western world for uranium tailings (Chapter 4.5.5).

A hydrological modelling of the new disposal (Chapter 4.8.3) suggested that by addition of one or more impermeable layers in the cover design , the water flux through the cap may be easily reduced to 1% of the net rainfall. Also addition of sorptive material to the bottom layer will significantly retard leaching.

5.2.3.1 Excavation and transport of the tailings

Due to the water saturated consistency ("pulpa") of processing residues stored in tailing No. 3, excavation will have to be done with a dragline or large cableway excavator, in order to avoid machines moving on top of the excavated material. The waste will partially drain on the edge of the tailing before being loaded. Transport will be in reinforced sealed containers, with sealed locked covers. The containers will be loaded aboard trucks that cannot drive on waste in the new deposit for unloading. These containers will be unloaded and emptied in the deposit by a cable device (sort of cable lift) or a crane with a large boom.

Drained waters will have to be collected in a sealed reservoir and water treatment capacities have to be installed.

Chapter 5 page 5

For the transfer of any drier tailings from other depositories, excavation and transport conditions are less difficult. This excavation can be done traditionally. Transport could be by dump trucks equipped with sealed and locked bodies.

When unloading, however, trucks cannot always drive on top of waste. In this case again, a crane with a large boom will be used to transfer the contents of trucks to the storage compartments.

5.2.3.2 Estimation of transfer costs (Chapter 4.5.4)

Costs were estimated by GESTER with about 3 million Euro for the transfer of Tailing 3 (110000m³) and 23 million Euro for the transfer of tailings T3, T5, T7 and T8 (880,000 m³) on the basis of prices before taxes applied in 2002 in western countries, by companies working according to western standards and using suitable materials.

Costs for radiological monitoring and radiation protection during the transfer of Tailing 3 works are estimated at 0.35 Mio Euro. Costs for continued monitoring after transfer of the Tailing are roughly estimated at 0.02 Mio Euro/year.

The costs presented however do not include investments for the water treatment installations nor potential costs with the disposal of contaminated trucks and other machinery.

Preliminary cost estimates were provided in the World Bank report (4) for the option Tailings relocation (based on the report by Clifton & Associates) (16), including emergency works for landslides hazard mitigation (2.5 Mio USD) as follows: approximately 21,7 Mio USD. These costs are expected to be seriously underestimated since costs refer to local market conditions.

5.2.4 Landslide Stabilisation

Transfer of the tailings does not solve fully the Mailuu Suu public safety issue due to river blockages caused by the unloading of landslides or unstable slopes and related inundation in a catastrophic scenario. Therefore the option of landslide stabilisation has to be considered among other options.

In a recent World Bank experts report (March 2002) several suggestions have been made to try to stabilize the critical slope areas menacing the tailings depositories either directly or indirectly in the Mailuu Suu river valley. The preliminary cost estimate of the World Bank for landslide stabilization for Koe- Tash and Tektonik Landslides including limited tailings remediation works amounts 24.4 Mio USD. These suggestions have been examined and assessed as outlined before (Chapter 4.2) and recapitulated below. In general the Consortium believes that landslide stabilisation by drainage is technically very difficult to realise and possibly not effective due to slumping of the drains by small continuous landslide moves. If to be realised, stabilisation can only be executed over very small areas and stabilisation will not be sustatinable in time.

Koi Tash landslide

Due to the volume of the Koi Tash landslide (estimated volume of unstable material is 5 million m3), to the thickness of the sliding mass (average 15m and 40 m at maximum), and to the severe earthquake conditions prevailing in the area, GESTER does not believe that the solutions presented by the Bank could be successful to stabilise the landslide under static and dynamic loading conditions.

Chapter 5 page 6

Tektonik landslide

The Bank considers that the slide could be stabilised with simple methods: deep drainage trenches, vertical shafts with radial drains, reshaping of the slope, small diameter wells.

Also in this case GESTER does not concur with the World Bank report of March 2002 and considers that the Tektonik landslide cannot be effectively stabilised for static and earthquake loading conditions with a reasonable cost effective civil engineering solution. The reasons are the type of landslide and the volume of the unstable soil mass. The landslide combines superficial mudflows on rather steep slope and mass movement. There is nearly no method to stabilise mudflows. The classical practice in Europe in mountain roads is to channel the mudflow above reinforced concrete structure. The only method to try stabilising the deep mass movement is drainage. The design of such a system would need a thorough investigation (boreholes, piezometers and inclinometers) to fully understand the deep sliding mechanism and the hydrogeological situation. In addition, the drainage system should not be sheared off by the slide. The drainage work will be a huge undertaking calling for a system of radial drains drilled from a main drainage gallery (wells from the surface will be destroyed). In addition, this system will be totally ineffective for the mudflow component of the slide.

GESTER (also see Chap 3.1) believes that given the size of this landslide, it is beyond human capacity to improve or stabilise the landslide.

Other experts (i.e. World Bank report of March 2002) have proposed stabilization by draining the Tektonik landslide, either with vertical drains drilled from the surface, or with sub-horizontal drains drilled from a gallery passing under the landslide. GESTER believes that both techniques are not realistic. For example, vertical drilling of a 0.30 m diameter wells would require machines that cannot be installed on the major part of the landslide surface. In addition, each drilling rig should be equipped with an electric-powered submersible pump and with an evacuation tube leading down to the river. In a landslide with such a brutal activity, these wells would be sheared off and their junctions cut, possibly even before they start operating. The other solution (sub-horizontal drains) involves the creation of a gallery in the substratum under the landslide. However, this would be extremely difficult since the substratum contains a major fault. Sub-horizontal wells would also be sheared off, probably before becoming operational.

Isolite Landslide

The Bank does not propose any method to stabilise the landslide (Relocation of Isolite plant is being considered). The Consortium considers that the landslide cannot be economically and successfully stabilised.

In conclusion GESTER considers that the classical landslide stabilisation solutions suggested by the World Bank will not be successful to stabilise the Tectonic and Koi Tash landslides in static and earthquake loading conditions. The technical feasibility of these actions is doubtful within a competitive budget. GESTER considers as well that the Isolite landslide cannot be stabilised economically. It is therefore proposed to find a solution to avoid the river blockage following a major landslide.

5.2.5 Solutions to avoid River Blockage (Mailuu Suu river diversion tunnel or river-channelling)

These options and their variants attempt the complete isolation of the tailings from the major transport vector which is the Mailuu Suu River realizing that the landslides, independently of the presence of the tailings, are a real hazard for the Mailuu Suu town public safety.

Chapter 5 page 7

A summary of the remedial solutions to avoid river blockage by projecting a Mailuu Suu River diversion tunnel or a river channelling is fully described in Chapter 4.2 and summarised here below.

5.2.5.1 River-Channelling

A solution may consist in channelling the river (even at maximum flow ) through pre-cast concrete tubes or through covered concrete channels which would be able to support the eventually accumulating sliding masses above and keep the river in free flow.

The tunnel is foreseen over a length of 2000 m with effective tunnelled parts over a distance of 1000 m. Dimensions are 7 m inner width and the prospected flow rate is 170 or 232 m³/s. The cost for this option is estimated with 21,4 million US$ (GESTER ; see Chapter 4.2 and Table 5.1.).

It follows from Table 5.1, that solution D (channelling the river) offers the lowest cost. Unfortunately the feasibility of the solution is not proven (technically difficult to excavate the stoney and wide river bed of a torrent) and the risk of landslide reactivation during the operation is a real hazard.

A previous cost estimate by the World Bank in March 2002 for the Hydraulic by-pass tunnel: amounted to 16 to 19 Million USD. Considering a flow rate of 170 m3/s, a 7 m diameter tunnel was found to be suitable to by-pass the tailings dumps area, and a unit cost of about 5,400 USD/m was assumed for this preliminary evaluation. A 3,500 m long tunnel was considered. Table 5.1 Remedial options proposed to avoid river blockage.

Solution Cost Mio US$

Main Comments

A. Long diversion tunnel LB 23.510 +5.329 28.839

• Should be combined to channelling of Kara Agach river to fully achieve the public safety objective (5.329 MUS$ included in the cost estimate). Some risk of reactivation of Tectonic landslide during this sequence of the works.

• Location of main fault and potential fault displacements (if active) to be clarified

• Location of mining galleries and shafts to be clarified

B. Long diversion tunnel RB 27.759 • Fully achieve the objective in terms of public safety

• Location of main fault and potential fault displacements (if active) to be clarified

• Location of Mining galleries and shafts to be clarified

C. Short diversion tunnels RB • Due to the constraints for locating the portals, the

tunnels cannot be short (unless T5 and T7 are relocated). Final solution equivalent to the long RB tunnel (Solution D).

D. Channelling the river 21,392 • The necessary excavations could reactivate Koi Tash

and Tectonic landslides during the works. Risk extremely difficult to evaluate. This makes the feasibility of the solution questionable.

Chapter 5 page 8

5.2.5.2 Mailuu Suu river diversion tunnel

The long diversion tunnel solutions (Solutions A and B) do achieve the public safety objective of decreasing almost fully the dispersion of radionuclides and heavy metals by the water flow. Solution A (Left Bank) is slightly more expensive and presents some risks of landslide reactivation1 when installing concrete elements to channel Kara Agach river (another potential contaminant transporter) flow in front of Tektonik Landslide. Therefore the best solution as considered by GESTER at the present state of knowledge appears to be solution B, the long diversion tunnel in the Right Bank which allows coping easily with the Kara Agach River.

GESTER believes that the crossing of active faults by the proposed tunnel (solutions A and B) does not impede the feasibility of the tunnel solution. Should there be evidence of recent activity of the Mailuu Suu fault, then engineering solutions could be designed to cross the fault. These solutions can be the combination of a larger chamber (say 8m diameter supported with flexible rock support solution) with the main river tunnel crossing the fault on a bridge inside the chamber. The tunnel in these critical sections could be a steel articulated penstock. The budget given in the present report allows coping with this type of situation along a few decametres. Local tunnel design adaptations will also be necessary if the tunnel crosses the area of underground mine workings. Due to these and the geological features, the tunnel should be excavated with classical drill and blast technique (and not with a full face tunnelling machine).

In this assessment costs estimated by GESTER for the tunnel construction (without landslides hazard mitigation and limited tailings remediation work) are close to 28 Mio Euro. These costs include design, construction (Mailuu Suu river diversion) and supervision (periodic inspections and fulfilment of public safety objectives) (also see Chapter 4-2).

Preliminary cost estimates were provided in the World Bank report (4) for the option Hydraulic by-pass tunnel at 24 to 27 Mio USD. This included some works for landslide hazard mitigation (2,5 Mio USD) and limited tailings remediation work (3Mio USD):.

It should be mentioned that resolving the problem of a possible river obstruction will not fully solve the problem for the people at Mailuu Suu. Imagine that by the impact of a landslide or an earthquake part of Tailing 3 is taken to the original Mailuu Suu River valley. People living nearby may be exposed to the tailing material by increased inhalation dose from contaminated dust and radon.

5.2.6 Proposed option: phased approach considering a combination of techniques

As outlined above, potential impact or indirect effect on some of the radioactive waste depositories deposits in the Mailuu Suu river valley (namely of Tailings 3,5,7,8,9,10,18,19,20 and 21) by seismic and/or slope- or structural instability - risks cannot be excluded. Historically this has been the case for tailings depository No.17 which was impacted by Tectonic Landslide in 1992. For this reason remediation options have to be selected that address the so-called accidental or catastrophic scenario as a non-negligible probability of occurrence.

Seismic hazards triggering slope instability and potentially loss of structural stability of waste deposits and associated repetition of river blockage events have to be classified as likely in the mid term and long term based on historical and even recent observations. Very little can be done against slope movements and seismicity in the critical sections of the Mailuu Suu river valley.

1 Risks are not as important as with solution D (reduced width of the concrete elements and necessary excavations).

Chapter 5 page 9

Therefore access restrictions, monitoring, emergency preparedness measures and structural or physical stabilisation of impoundments that have to be considered as unstable in their present condition (i.e. Tailing 3) can only have short to mid term significance but are nonetheless necessary.

Under present project, considering the project objectives, the Consortium focussed its attention on Tailing pond 3.

In the very short term it is proposed to proceed with the fencing of the tailings of concern (Tailings 3, 5, 4, 7 and 13), put on warning signs on all other tailings awaiting fencing, and perform the minimal maintenance work (repair and cleaning of gutters, damaged dams, etc…) and monitoring. Additionally to execute fully the short term stabilisation works on Tailing 3 as proposed in Chapter 4.4.1 (Reinforcement of foot of tailing and displacement of upper dike with 20 m with a resulting increased stability of 40 %). Even if these short term remedial options will not guarantee tailing stability following an earthquake of moderate intensity, they are required given the actual limited stability of the tailing.

Since an additional stabilisation is necessary for important earthquakes, it is proposed to stabilise the tailing 3 downhill embankment using COLMIX treated columns in the short-mid term. It can be decided by the responsible authorities that these stabilisations are sufficient for the reasonable foreseeable impediments. Under the consideration that catastrophic conditions could bring down (part of) Tailing 3 to the Mailuu Suu River, it may be decided to relocate the tailing. Such a translocation cannot be accomplished before several years since detailed pilot studies of the new tailing still have to be prepared. On top of that the transport conditions, the important investment funds, the meeting regarding available material, equipment and personnel which are still not fully available in Kyrgyzstan. It then becomes important to start the first stabilisation measures presented as soon as possible.

For all the other tailings the actual stability should be investigated, possibly following the method applied for Tailing 3. It should be decided if the actual stability is adequate or if it should be improved and if the improved stability is acceptable.

For the long term, and following the evaluation of a number of remedial options (Chapter 4.2, 4.4, 4.5), summarised in Table 5.2., two options are retained

- C: Excavation and transfer (first of T3 (110000 m³) then , T5 , T7 and T8 (800000 m³) to an alternative safer site which could be Tailings depository No. 15 (at 15 to 20 km distance) pending more detailed investigations which are necessary and beyond the scope of this Tacis project.

- F : Diversion of the Mailuu Suu river by the long diversion tunnel in the right Mailuu Suu river Bank which allows also to cope easily with the Kara Agach River

Both options could only be outlined to some extent within the framework of this project and require an even more detailed site investigation, detailed feasibility study and project design before a final decision can be formulated. Obvious drawbacks or obstacles to be overcome for both options are summarised in Table 5.2. and below.

Option C: (Chapter 4.5)

Advantages

- Removal of radioactive sources. Almost annihilation of the potential of dispersal of radioactivity.

- High public assurance

Potential disadvantages or problems

Chapter 5 page 10

- Difficulty in extracting the radioactive residues most probably as a mud (probably only applying for Tailing 3)

- Radiological and environmental impact of tailings transfer and potential public disturbance (therefore sealed trucks required)

- Environmental suitability and sustainability of new site

- Additional costs related to necessary radiological surveillance and radioprotection measures during and after operation and clean up and also related to the necessary water collection and treatment facilities and post project monitoring.

- The relocation of the tailings does not solve fully the Mailuu Suu town public safety issue due to inundation in case of catastrophic scenario.

Option F (Chapter 4.2.)

Advantages

- The area will become a nearly dry sanctuary in which tailings are isolated without any adverse river influence.

- Stop of dispersive action of river

Potential disadvantages and problems

- Knowledge of exact location of old mine workings

- Tunnelling in unstable terrain (faults, young fractures, neo-tectonics, seismicity and related phenomena) could be problematic by itself and ultimately be capable to trigger mass movement all by itself.

- Especially the tunnel portal entering the hillside beneath unstable slope sections would have to be reason for serious concern . Undermining of the slope by the tunnel with consequent disturbance to the overlying rocks and soils and depression of the water table can lead to instability problems

- Proper maintenance and regular surveillance of the tunnel section and related costs.

- Potential tunnel blocking

- A tailing dump taken to the ‘former’ Mailuu Suu river valley, may lead to an increased exposure of the population due to increased radiation exposure.

According the multi-staged approach proposed (Option 6 in section 5.1.) while continuing improving the physical stability of T3, monitoring, preparing emergency preparedness measures and establishing access restrictions and identifying population transfer zones in the short term, simultaneously start in the short and short-mid term with a mid-long term perspective assessing the feasibilities of both options C and F based on additional information gathering. Options should be evaluated in terms of technical feasibility, health and environmental impact, economic costs and public acceptance until a decision can be made to choose between the two alternatives which will be projected subsequently.

Chapter 5 page 11

Table 5.2. Summary table: remedial actions

Options Cost - Mio Euro Main Comments A. Do nothing (Institutional control)

• Minimal monitoring required

• Minimal actions to maintain actual dam stability, to guarantee deviation of surface water flows, …

• Minimal actions required to prohibit access to tailings

• Given the risk of landslide and the potential radiological consequences not considered as an option by the Consortium

B. In situ stabilisation of T3

2 to 4 (COLMIX 2,35)

• Significant for the short to mid term due to the actual state of limited stability of T3

• Remaining risks for the longer term (seismic and landslide hazards)

C. Transfer of risky tailings to a safer site

3.35 (T3) >23 (T3, 5,7,8)

• Technically complex undertaking (western experience and technology required)

• Adequate water treatment technology, transport, and radioprotection necessary

• Technical feasibility to be done parallel to appropriate site investigation of proposed site (T15) and development of a detailed engineering concept for disposal cell construction.

D. Landslide stabilisation 24.4 (WB-estimate incl.limit. tailings remed.)

• Doubtful technical feasibility of sustainable stabilisation success for Tektonik- and Koi-Tash landslides under static and dynamic (earthquake) loading conditions. Reasons are type of landslide (mudflows!) and volumes of unstable soil mass. Drainage systems will be sheared off.

• Reasonable cost effective civil engineering solution to solve the entire problem is questionable, stabilization can only very locally and temporarily be applied successfully

E. Long diversion tunnel LB

23.510 +5.329 28.839

• Should be combined to channelling of Kara Agach river to fully achieve the public safety objective (5.329 MUS$ included in the cost estimate). Some risk of reactivation of Tectonik landslide during this sequence of the works.

• Location of main fault and potential fault displacements (if active) to be clarified

• Location of mining galleries and shafts to be clarified

F. Long diversion tunnel RB

27.759 • Fully achieve the objective in terms of public safety

• Location of main fault and potential fault displacements (if active) to be clarified

• Location of Mining galleries and shafts to be clarified

G. Short diversion tunnels RB

• Due to the constraints for locating the portals, the tunnels

cannot be short (unless T5 and T7 are relocated). Final solution equivalent to the long RB tunnel (Solution F).

H. Channelling the river 21,392 • The necessary excavations could reactivate Koi Tash and

Tectonik landslides during the works. Risk extremely difficult to evaluate. This makes the feasibility of the solution questionable.

Chapter 5 page 12

5.2.7 Protection measures for drinking water supply

The only possible protection measure for the drinking water supply in the Mailuu Suu river valley is to extend the existing conduit all the way downstream the Mailuu Suu River (in accordance with the Mailuu Suu Hydraulic Service Project).

The right bank diversion tunnel option proposed as one of the potential long-term remedial options will also to a large extent guarantee the quality of the drinking water.

5.3 Decision Making The landslides, independently of the presence of the tailings, are a real hazard for the Mailuu Suu town public safety. In a Western Europe financial and institutional context, with the pressure of public opinion for the no human loss concept in public safety, the risk of river blockage followed by the temporary dam failure risk would definitely lead to make decision in favour of a river diversion tunnel. A recent example from the French Alps is quoted in Chapter 4.2. In Europe, diversion (or connecting) tunnels are also used in dams reservoir engineering where rock avalanche could isolate parts of the reservoir leading to uncontrolled blocked reservoir sections.

The tailings, when (slightly) impacted, independently of the presence of the landslides, are a potential hazard for the inhabitants of Mailuu Suu and people living downstream. In United States an example can be quoted where a uranium tailings or waste pile was transferred out of valley to prevent its loss of stability in case of flooding and than stored in disposal cell concept impoundment higher up topographically and several km away from the danger zone.

This demonstrates that decision making is very much subject to the socio-economic, socio-political and cultural context.

Decisions on the introduction of remedial measures for long-lasting exposure situations are subject to considerations of which option will result in the highest a net benefit. In reaching such decisions it is important to consider carefully the benefits and disadvantages based on multicriteria assessment and aaplication of optimisation procedures because some remedial actions can significantly disrupt the exposed population.

The analysis should address both radiological and non-radiological issues. Examination of the former will, in principle, be rather straightforward since it involves the radiation detriment to be averted and the costs associated with the remedial action (including both the direct cost of the action and costs to affected parties).

Several factors (attributes, accounts) have to be considered in the selection of an optimum remediation strategy, e.g. effectiveness of the remediation with respect to dose reduction, monetary and social costs, impact on the environment, acceptability of the public, personnel safety etc.

For the reasons stated above decision making in particular relies on close integration and cooperation between Kyrgyz authorities, experts and the local community. Comments of and discussions with all stakeholders and involved parties must be taken into account in a systematic way.

When the performance and costs of all the protection options have been assessed, a comparison is needed to define the optimum protection option. When the optimum is not self evident, the comparison can be carried out using a quantitative decision-aiding technique. The result of the application of the quantitative techniques is known as the analytical solution. If there are non-quantified, radiological protection factors to be taken into account, the analytical solution is not the optimum solution. The qualitative factors will have to be combined with the analytical solution to give the true optimum. Of the different techniques available there are, amongst others, cost-benefit analysis and multi-attribute utility analysis.

Chapter 5 page 13

Cost-benefit analysis involves a balancing of costs in order to establish optimum levels of radiation protection and health/life risk. Optimisation of protection can be generally limited to the selection of the best available combination of cost of radiation protection, X, and cost of detriment, Y, by minimising the sum (X + Y) and thus maximising the net benefit, B.

The essence of multi-attribute utility analysis is to use a scoring scheme (or multi-attribute utility function) for the relevant factors. If the score (or utility) is the same for two options there is no preference for one or the other and both options are, therefore, optimal. As a basis for comparison between options or alternative strategies, a multi-attribute value function approach can be used. There are two major components of such a value function: the evaluations of each of the alternative strategies with respect to the considered attributes, known as the scores or utilities and scaling factors which reflect the relative importance of each of the attributes, known as the weights. The use of utility functions allows introduction of factors which are not easy to quantify in monetary terms as is required in cost-benefit analysis. The utilities and weighting factors can be expressed in an additive form to give an overall evaluation of each of the alternative strategies, or options (see further).

Nowadays, multi-attribute utility analysis (MAUA) is advocated as an adequate means to select the optimal remedial option. Since it was the objective of this project to study the feasibility of a preferred option (and even more options are evaluated to a reasonable extent) and not to engage in a full-scale multi-attribute analysis, this methodology is only described to some extent and may be applied in the aftermath of present project phase.

The difficulty in this technique lies in the selection of the attributes considered important, the dependence of some attributes, the subjectivity in assigning weighing factors and subjective value judgements which will not be universally accepted. However, since it does not involve (in principle) expression of all factors in terms of a common denominator (e.g. monetary value) multi-attribute analyses is in principle capable of dealing with the most important factors. However, this kind of structuring can be helpful in promoting constructive discussions with involved parties and openness in decision making by providing a framework for the comparison of alternatives.

Assessment of remediation options and ranking

In order to select the optimal option from a list of alternative remediation options the evaluation must weigh the benefits and losses of each option. This involves four basic steps :

- Identification of possible remediation options .

- Identification of the impacts (benefits and losses) of each option to be included in the evaluation (assessment criteria);

- Quantification of the impacts (benefits and losses) for each of the criteria;

- Assessment of the combined or accumulated impacts for each option and comparison of these with other options to develop a preference list (ranking, scaling and weighting) of the options.

There may be threshold values for a particular impact which, if not achieved, constitutes a fatal flaw. A fatal flaw is one which, of itself, renders the option under evaluation unacceptable. Thus failure to meet, for example a mandatory water quality standard, may be a fatal flaw. Thus, step 2 includes a screening out of all options which fail to meet threshold values for all criteria. All options which survive the threshold test at step 2 must be included in the integrated (combined and cumulative) impact assessment of step 3. The diversity of impacts that must be considered makes integrated (combined and accumulative impacts) assessment difficult. To a large extent any comparison is subjective and depends on the flavour preference (value basis) of the analyst. It is not possible, and probably not desirable, to remove this subjectivity as each analyst seeks to

Chapter 5 page 14

have his/her value basis applied in the analysis. It is therefore an advantage if the evaluation methodology (analysis) is systemized and transparent allowing the various analysts to clearly indicate their value basis and results.

Following the MAUA, each of the remedial options considered in Table 5.2. and the advocated option 6 (phased approach, combined remedial actions, see Chapter 5.1), can be assessed based on the different attributes (factors) proposed. For example:

- Radiological

- Environmental

- Public safety

- Technical feasibility

- Stability and sustainability

- Economics

- Socio-political

- Risk

To each of these attributes a weighing factor is applied by each individual assessor or by the community of stakeholders following discussion.

Criteria characterizing the attributes should be defined. Criteria used generally must include:

- Compliance with regulatory requirements and international standards and guidelines (and with remediation objective)

- Compliance with radioprotection requirements

- Longevity of remedial action taken.

Ranking of remediation measures should also be considered according to the degree of urgency. Selecting a complete list of criteria ensures that no a priori judgments have been made regarding the selection of any alternatives. The criteria deemed important (selected fundamental or high value criteria) to the assessment of alternatives for the remediation of wastes from uranium mining and milling in Mailuu Suu are given in Table 5.3.

Chapter 5 page 15

Table 5.3 : Example of a hierarchy of factors (attributes) to be considered in a multi-attribute utility analysis for Mailuu Suu

1. S

tatu

s quo

2. S

tabi

lise

taili

ngs

in si

tu,

3. r

eloc

atio

n

4. st

abili

se sl

opes

5a. R

iver

div

ersi

on(t

unne

l)

5b. R

iver

cha

nnel

ling

6. M

ultip

le so

lutio

ns a

nd p

hase

d ap

proa

ch

ACCOUNT:long termshort termlong termshort term

long termshort termlong termshort term

Regulatory approvalPublic Acceptance

long termshort term

Dose (collective)

Gamma

Radiological Impact

OptionsHierarchy of factors

CRITERIA:Radon

Dust

Ingestion

Dose (individual)

stability

Public Safety & Risk

Other disturbance

EnvironmentalImpact

Surface WaterNoise

geochemical

geotechnical

GroundwaterAir

Sustainabilitywaste materials

waste watersDisposal and

treatmentFeasibility

CostsEffectieness

TechnicalFactors

Maintenance and surveill. timeSimplicity

Level of Institutional

Social Political Impact

Score:

Employment

Surface areas

ResourceCommitment

Materials neededTime,costs

Energy, water

Chapter 5 page 16

Each criterion has one or more indicators with which to measure, either qualitatively or quantitatively, the impact (benefit or loss) to each criterion by the various alternatives. For example, the criteria of water quality may have a list of indicators including, radionuclide-content, pH, concentration of Total Dissolved Solids (TDS), sulfate concentration etc. These indicators are likely different at different stages of remediation and therefore should be divided into time periods (before, during, after remediation).

Compliance or none-compliance or partial compliance with the indicator for each criterion is valued with a score, which can be derived from a utility function.

The utilities (scores per indicator or criterion) and weighting factors can be expressed in an additive form to give an overall evaluation of each of the alternative strategies, i, or options:

U wi jj

n

==∑

1

uij

Ui is here the overall evaluation of Option i, wj is the weight assigned to attribute j and uij is the score or utilities of the n factors (attributes) associated with each of the alternative i on attribute j. The higher the value of merit, Ui, the better the overall ranking of the option.

Preliminary ranking of the remedial options studied

It goes without saying that the MAUA requires an enormous amount of input for adequate evaluation which is, as said not the objective of present project phase.

If we consider the ‘Do nothing’ option (which includes as said restricted access, some monitoring, essential maintenance works), the radiological monitoring data show that; the actual gamma and radon values recorded are not exceptional for uranium mining area; additional external exposure above background is smaller than 0.4 mSv/a, except for one house in Kara Agach, action levels for radon in houses is not reached; the actual contamination of the river water is below the exemption limits for drinking water; but all soil and vegetation and crop samples collected at Kara Agach or at the tailings exceed the limits.

Hence, except for the people residing close to or on the Kara Agach mining waste dump, there is no actual radiological risk for the people. To assure radiological safety, given the present conditions (no accident), access to the tailings should be restricted.

This do nothing is actually ‘safe’ but there is the eminent risk of moderate or fierce earthquakes and the probability of a landslide blocking the river or taking tailing material to the river in its course down. The estimation and ‘valuation’ of the risk component will be very important.

In case (part of) tailing 3 is taken to the river, the drinking water limits and the individual dose limits are exceeded, hence, in case of the ‘fatal flaw’ approach, action to reduce the risk of an accident or disaster to happen is compulsary and must be evaluated.

If we make a simple cost-benefit calculation. In order to do this we express the benefit, the cancelled out potential dose increase following an accidental or a catastrophic scenario, in monetary terms. This can be done by assigning a cost value to a dose increment following a disasater: a cost per unit dose increment or when applying a remedial action, the associated monetory benefit of avoiding a unit dose, the reference value, α. For European countries a reference value of α between 25,000 USD per manSv dose increment or avoided dose and 250,000 USD Sv-1 is applied (Vandenhove et al. 2000). The Nordic radiation protection authorities have recommended a maximum value of α of 100,000 USD Sv-1.

Following an accidental scenario, the major change to the radiological exposure will come from the ingestion of contaminated drinking water (if river water would be consumed), contaminated

Chapter 5 page 17

fish and of contaminated food following irrigation with contaminated river water. Contribution from increased external radiation and inhalation of radon following radionuclide accumulation in the soil as a result of irrigation is just a small fraction of the total dose (compare Tables 4.8.4.13 and 14 and Tables 4.8.4.20 and 21).

The difference in individual dose in the actual situation and following a disaster resulting in a breakdown of Tailing 3 and a flow of the complete tailing content to the river under average river flow regimes is in large the difference in individual radiation exposure between Table 4.8.4.20 and 14; i.e. 26 mSv/a for an adult and 44 mSv/a for a child.

Considering the Kyrgyz population downstream Mailuu Suu actually using the river water as drinking water and not from a water treatment plant as in Mailuu Suu (5000 people, personal communication M. Muraliev, KyrgyzGIIS; we assume 50 % children) we can calculate the additional collective dose following an accident. If we would include all people (also Uzbek) living in the Fregana valley, the collective dose would be higher. Considering an alpha value varying between 25000 and 250000 Euro Sv-1 and 20 to 100 % of the tailing 3 material being taken to the river, the resulting equivalent dose increment costs are presented in Table 5.3. Values range between 0.88 and 43.75 Mio Euro, covering the full scale of the costs of the remedial options studied. Table 5.4. Equivalent dose increment cost in case 20 or 100 % of Tailing 3 is taken to the Mailuu Suu river (average flow regime), considering 5000 people (50 % children) living downstream Mailuu Suu

POPULATIONIndividual dose

accident (mSv/y)increment following 25000 Euro/Sv 250000 Euro/Sv

adult child total dose (Sv)equivalent dose cost

MEuroequivalent dose cost

MEuro100 % of tailing 3 to river 1 26 44 175 4.38 43.75 20 % of tailing 3 to river 0.2 26 44 35 0.88 8.75

WORKFORCE mSv Sv

Workers COLMIX 229 0.229 0.02 0.05Translocation 1157 1.157 0.09 0.23

COSTColmix 2.35 MEuroTranslocation 3.25 MEuroTunnel in right bank 27.76 MEuro

Table 5.4. is just given as an example to provide a rough balancing between benefits and costs. It can be assumed that the remedial actions will (partially) annihilate the dose increment.

Depending on the value selected for α (depending on countries GNP; subjective; subject to discussion) and the extent of disaster, the options proposed in Table 5.2. are justified are not.

In the example presented, the very short term remedial option for Tailing 3 (relocation of small dam and enforcement at foot of main dam) is always justified given the present example since the cost of the action is << 0.88 Meuro. The stabilisation of Tailing 3 by COLMIX and transport of the tailing 3 content is not justified in case of a disaster of rather limited extent (20 % of tailing to river) and a low α value since the costs (2.5-3 Meuro) exceed the monetary benefit (0.88 Meuro). Under all other conditions of the example presented, the actions are justified. The tunnel option is only in case of important disaster linked with Tailing 3 and rather high α value.

When an earthquake of moderate intensity would result in a dam brake resulting in a flow of 50 % of the T3 content to the river (expected equivalent dose increment cost 2.2 Mio Euro when considering the lowest alpha value), the application of the COLMIX stabilisation method (cost 2.35 Mio Euro including radiation protection costs) which would increase the tailing stability so it can resist moderate intensity earthquakes is justifiable on a cost-benefit basis.

Chapter 5 page 18

It can be deduced from Table 5.4. that the equivalent ‘dose increment cost’ for the radiation workers is negligible compared to the total project cost.

5.4 Proposed Future Work Apart from short term (and required continued) actions to restrict access to tailing, for tailing maintenance, minimal monitoring, apart from the short term to mid term stabilisation work as proposed for T3, activities to assess the feasibility of remediation options C and F above should start simultaneously until a decision crystallizes on the preferred option.

During the initial phase of the the feasibility study, activities (pilot testing) regarding landslides hazard mitigation should be more or less simultaneous with the activities on the tailing deposits in order to further assess their physical conditions. This should be carried on until reaching the required level of knowledge for a selection of the preferred remedial option. Also it is important during this study to complement and maintain the system and strategic locations for an environmental monitoring network along the conceptual contaminant pathways from source to receptor.

An emergency prepardness plan should be developped and established.

Since we propose a phased remediation approach, additional information has to be collected and additional investigations have to be performed at different levels.

Generally, the actual situation should be more comprehensively recorded. Due to budget constraints, only rather limited environmental monitoring could be performed. Information should be gathered to have a clear idea of the reference conditions, the environmental base line conditions with which the remedial actions should be compared. The majority of these requirements are summed up below.

In the phased approach we also proposed to (temporarily) stabilise the tailing 3 with the COLMIX method. Most important complementary studies and field investigations required are the following

- More detailed geotechnical and geophysical investigations of tailing 3

- Inertion tests to assess the increased mechanical resistance after the application of COLMIX

- Assessment of tailing stability with impacting factors and after COLMIX application

- More detailed radionuclide and other contaminants content of tailings for radiological and environmental assessment and to assess hazard to workers

- Design activities

- Refine the proposed design and elaborate a complete workplan

- Assess need for water treatment plant and dimension and cost plant if deemed required

- Detailed radiation protection guidance and programme during execution of works and radiation and environmental monitoring

- Post-project radiation and environment monitoring programme

- Costing

For Option C, transfer of selected tailings to a safer site, complementary studies and field investigations required are the following :

- Geotechnical and geophysical investigations of tailings considered for relocation and the new disposal area (borings and tests)

- Geological and structural survey of the new disposal site

Chapter 5 page 19

- Topography survey of new disposal site

- Assessment of actual tailing stability (with impact of landslide/earthquake/suction power of quickly emptying lake following river blockage dam break)

- Radionuclide and other contaminants content of tailings

- Environmental baseline study

- Dispersion relevant parameters for tailing materials/bedrock/sediment covers/bedrock

- Hydrological and hydrogeological information of tailings and new disposal site

- Radiological assessments

- Environmental hazard assessments

- Actual road characteristics

- Engineering design of transport system

Design activities to be performed in the next step of the project should:

- Detailed work programme and performance for loading at each specific tailing and un-loading of tailings at new disposal site

- Detailed road improvement plan or road construction works

- Investigation (and design) of potentially other transport mechanisms

- Refine the proposed disposal design and adapt the detailed siting to the amount of tailing material that has to be allocated at the site.

- Assess need for water treatment plant and dimension and cost plant if deemed required

- Detailed radiation protection guidance and programme during execution of works and radiation and environmental monitoring

- Post-project radiation and environment monitoring programme

- Costing

For option F. Long diversion tunnel RB the complementary analysis of existing documents supplemented by complementary studies and field investigations should bring clear answer and design parameters on the following aspects:

- Precise localisation of old mining works

- Detailed topographical survey especially portal areas and Kara Agach River valley.

- Geological cross section along tunnel route.

- Precise localisation of the Mailuu Suu fault. Diagnosis on fault activity and evaluation of possible displacements (average yearly displacement and estimated one in case of earthquake of various magnitudes (especially for the design basis earthquake – DBE- and maximum credible earthquake- MCE).

- Peak ground acceleration for various earthquake return periods (following western approach: tectonic analysis + statistical analysis of observed earthquake events).

- Final evaluation of the Mailuu Suu and Kara Agach rivers floods for various return periods (and especially the 1/100 year flood).

- Stability of slopes in tunnel portal areas.

- Environmental base line study, radiological and environmental risk assessment

Chapter 5 page 20

About 4 to 5 boreholes (with measurement of piezometer levels, water testing and sampling at tunnel level) should be drilled on the tunnel route. The location of the boreholes will be determined after the preliminary geological desk studies to confirm or amend the preliminary geological interpretation and adjust if necessary the tunnel route.

Note: In case a more detailed evaluation of inundation levels in Mailuu Suu town in the catastrophic scenario would be required, then a complete Dam Break analysis should be performed (with accurate topographical sections).

Design activities to be performed in the next step of the project should:

- Adapt the tunnel route to the geology,

- Finalise the hydraulic sizing of the tunnel,

- Detail the engineering solutions for the crossing of faults and mining galleries,

- Give the recommended location for Kara Agach incline,

- Make a zoning of the tunnel route in terms of internationally2 accepted rock mass quality ratings (Bienawski RMR3 or Hoek and Brown GSI4 or Barton Q system) with associated solutions for temporary rock support (before concrete lining),

- Design the tunnel intake and outlet structure,

- Finalise the route of the permanent road

- End up with a cost estimate including a revised evaluation of the unforeseen and contingencies,

- Give the preliminary construction program.

Assessement of the radiological consequences of a disaster scenario requires important additional information

For the evaluation of the potential total sediment load of a river

- hydraulic characteristics of the river such as the discharge, the depth, the shape of the wetted cross-section and the longitudinal bed slope

- characteristics of the sediments, such as the granulometric curve as coarse sediments are not so easily transported as fine sediments are.

For the disaster scenarios of a landslide blocking the Mailuu Suu river downstreem T5 and 7:

- topography of the river bed and borders upstream the natural dam and the river flow in order to calculate volume of the lake formed and the level to which the tailing is inundated

- information on the stability of Taling 5 and 7 (impacted by lake) or tailings 3, 8, 18, 21 and 22 (potentially impacted by flood wave) should be available to predict if the tailing dams would errupt yes or no

- content of the radionuclides in the tailings for predicting the concentration of radioactivity in the river if the tailing dam would fail

2 For Tunnel construction, there will be international bidding. The geological information should be provided to tenderers in an internationally accepted system. 3 Rock Mass Rating (Bienawski) 4 GSI: Geological Strength Index (Hoek and Brown)

Chapter 5 page 21

- content of the radionuclides in the tailings and tailing granulometry to predict the amount of radioactivity leached from the tailings to the lake water and hence to the river after the natural dam rupture

In addition to the detailed investigation of options C and F as mentioned above and the additional information required for assessing the radiological exposure in case of a disaster scenario, one should engage in

- a thorough risk characterisation

- an assessment of the averted risk by the option

- a thorough radiological assessment

- a thorough environmental hazard assessment

- a study on the economic and socio-political implications of the remedial options, including the do nothing option and considering the risk factor (accident and disaster)

Local stakeholders, already included in all former steps, should then be invited to assist in the selection of the optimal remedial approach by CBA or MAUA, or other optimization technique.

5.5 Information exchange, communication of project results to population, decision-takers, stakeholders and inclusion of stakeholders in discussion As mentioned before, in order to be able to propose a remediation approach which is accepted by the local authorities and stakeholders, involvement of the decision makers, the local scientists and engineers and the local stakeholders is required in every project phase. This we tried to achieve by different actions exemplified below.

5.5.1 Communication of project results/Building population trust

5.5.1.1 General Approach and Steps taken

At all stages of the project the public was informed and involved, where possible national and Consortium experts informed the public about the environmental situation, and explained how they will deal with the problem of Mailuu Suu, and communicate the expected outcome. Experts work towards public acceptance of their actions.

In order to make the information flow to the population more efficient and more transparent and secondly, to get the Mailuu Suu population involved in the monitoring and control of stabilisation and remediation, Working Groups have been created and local Stakeholders have been identified.

The Deputy Governor of Mailuu Suu, Mr. Ashir Abdullaev, also representative of the Ministry of Emergency Planning, agreed together with Mr. N. Mambetov, of the Sanitary Epidemiological Station (SES) to be involved in the local co-ordination. They agreed to co-ordinate local people who would

- assist in the local monitoring campaign and the surveillance of the monitoring equipment

- assist in the technical works

- to assist in the establishment of a local awareness network

- provide information to stakeholders and the public

- For this purpose the contractor also contacted local companies potentially affected by the programme of investigations and remedial steps that have to be taken or representing important stakeholder groups.

5.6.1.2 Meetings held to Create Relation and Establish Trust with Population

Chapter 5 page 22

The first round of meetings for public trust building took place during the first field visit in June 2001 in Mailuu Suu. These meetings were targeted to provide information on the Tacis programme and to foster interest and co-operation among local authorities and stakeholder representatives of the Mailuu Suu town and area. Another aim was to obtain an idea on their views and perspectives on the uranium mining legacies in Mailuu Suu.

Meetings took place with:

- the Mailuu Suu city administration and local Kenesh

- The mayor of Mailuu Suu Mr. Turusbek Toktosunov and head of the local Parliament (“Kenesh”) Mr. Sarchanbek Ünusaliev. Presentation of Program objectives. Explanations concerning the set up and aim of local Working Groups with the help of the town administration. Identification of local stakeholders

- The Director of local factory ISOLIT : Mr. Leonid Muratov

- The Director of Joint Stock Company Mailuu Suu Electric Lamp Factory Mr. Nicolay A. Melker. Largest employer in Mailuu Suu with 1300 employees.

- Chief Medical doctor of Sanitary Epidemiological Station (SES). Dr. Kochkan Aidarov

The second round of meetings for public trust building took place during the 2nd field visit in August 2001 in Mailuu Suu with representatives of the town and local parliament together with the local volunteers for the Working Groups that were created at this occasion. The objective of these meetings was to provide more detailed and first hand and practical information from Tacis and Beneficiary experts on current work of the Tacis team and subcontractors and to foster the integration of Working Groups in these activities. At this occasion during the field campaign (Aug.18 to 29) members of the Working Groups (notably Mr. Mambetov, Mr. Shaihutdinov, and Mr. Mamataliev ) were integrated in current field activities such as site surveying, environmental sampling, field investigations on tailings, waste deposits and landslides, and drilling activities.

The first Public Meeting took place October 3 , 2002, in Mailuu Suu and included a presentation of the project, of actual radiological situation and potential risks and remedial actions studied by Consortium; possibility to ask questions; very positive response (see list of participants in the Annex 5.1). Working Groups engaged in the preparation of public meetings

5.5.2 Working Groups

5.5.2.1 Working Groups Objectives and Activities

Three Local Working Groups in Mailuu Suu have been created to establish networks of local teams for a continuing working environment after termination of the project.

These local Working Groups (WG) involve actively the local population (volunteers), from relevant sectors of the community with a vested interest in the problem:

- the local and regional administration,

- public health authorities,

- teachers,

- stakeholders and representatives of the population concerned

During the first field campaign with local subcontractors in August 2001 the latter assisted with the establishment of the local WG´s by integrating WG participants in their work thus providing information and training .

Objectives of WG activities are summarised as follows:

Chapter 5 page 23

- Voluntary commitment of the local people and authorities in order to foster recognition of the importance of active local involvement

- Creation of self confidence and trust amongst the local population and encouragement of motivation to take initiatives;

- Improvement and concrete progress that is felt by local population;

- Establishment among the local community of a common and realistic view of the local radiological situation and how it can be managed locally

- Ensuring information of the population at all times during the project;

- Transfer of know-how, training and practical study.

An important aim of the project was also to encourage a dialogue and transfer of know-how from the Contractor, Subcontractors and the Beneficiary to local organisations in order to enable them in the future to perform similar work on their own, integrating the feedback of Western experience and of the existing know-how in Kyrgyzstan. Therefore each working Group integrates a Representative of the Beneficiary and is itself integrated as much as possible in the activities of the Contractor and Subcontractors. In this framework the role of the Beneficiary is not limited to providing background information and solving local organisational problems, but also includes active participation in the project related tasks. Also this work structure is meant to ensure that the project results are adapted to the local needs and to local organisational structures

Public active engagement is also designed to ensure public involvement in the decision making process and maximal assurance of continuation of site safety (protection and maintenance of fences and monitoring stations) and of surveillance after termination of the TACIS project.

5.5.2.2 Working Groups established in 2001 and their composition

In August 24, 2001, the mayor of Mailuu Suu Mr. Abdynazar Shermatov presented candidates for community volunteers to participate in the following Working Groups:

- WG1: Quick action and environmental (radiological) monitoring and sample analysis

- WG2: Geostabilisation / hydrogeological monitoring and remediation (works)

- WG3: Involvement of local stakeholders and local awareness

For each of these major categories of work the following persons from the Beneficiary Organisation (Ministry of Ecology and Emergency Situations and Civil Defence of the Kyrgyz Republic) were designated responsible by Mr. Moldobekov (National Co-ordinator of the Ministry) June 20, and August 27, 2001:

- WG1: Mr. Jenish Shatemirov, leading expert of the Monitoring Department of the Ministry and Mr. Minvalli Shaihutdinov, Safety Engineer , City of Mailuu Suu (and acting on behalf of the Ministry )

- WG2: Mr. Alexander Meleshko, Head of Monitoring Department of the Ministry

- WG3: Mr. Ashir Abdullaev, the Deputy Head of the Mailuu Suu “Kenesh” and Head of Civil Defense for the city of Mailuu Suu (acting as local representative of the Ministry )

Mr. Nemat Mambetov of the SES and Mr. Ashir Abdullaev Deputy Head of the local “Kenesh”in Mailuu Suu were appointed to select volunteers from the city of Mailuu Suu for participation in the Working Groups .

The following persons have been selected, agreed to participate and were assigned in August 2001:

Chapter 5 page 24

- WG 1 : Mr. Nemat Mambetov, Sanitary Epidemiological Station (SES); Mr. Akylbek Tagaev, Ecologist, City of Mailuu Suu; Mr. Minvalli Shaihutdinov, Safety Engineer , City of Mailuu Suu; Mr. Rasul Mamataliev, Specialist of City Administration on youth questions

- WG 2 :Mr. Victor Barinov, Chief engineer of the water supply system; Mr. Tenpe Chki, Economist , City of Mailuu Suu; Mr. Japarov Yuri, Security Officer, Light Bulb Factory

- WG 3 :Mr. Ashir Abdullaev, Deputy Head of the local “Kenesh” and Head of Civil Defence Department in Mailuu Suu; Mr. Alym Juraev, Chairman of the Village Administration

The Deputy Governor of Mailuu Suu, Mr Ashir Abdullaev, and Mr. Nemat Mambetov, of the SES are in charge of the co-ordination of all local activities of the Working Groups.

5.5.2.3 Projects Related to Working Groups

Specific Tasks and Projects Related to Working Groups

WG1: Quick action and environmental (radiological) monitoring and sample analysis

Local Working Group (WG) l was created with tasks aiming, at concrete improvement in the quality of life regarding the environment including the radiation dimension. Tasks were defined as follows :

- Monitoring and environmental sampling (techniques, philosophy and procedures are explained and trained by SCK Experts for radiology together with subcontractors CHU LABORATORIES, ALEX STEWART ASSAYERS, and by GESTER Experts for geotechnical monitoring).

- Introduction to TLD dosimeters for long term monitoring and to passive Rn detector installation etc. by SCK together with subcontractors CHU LABORATORIES and ALEX STEWART ASSAYERS. Members of WG 1, in particular Mr. N. Mambetov , Mr. M. Shaihutdinov and Mr. R. Mamataliev were integrated in the practical field work during the August 2001 campaign.

- Supervision and security of sites of sites where measuring devices have been installed

- Interfacing with local and other relevant authorities and with subcontractors and the other two WG`s

WG 1 Project:

Identification of Critical Group characteristics

A list of relevant parameters was distributed and discussed with local WG 1. The parameter requirements have then been fine-tuned to cope with local characteristics and the data have been collected during a series of interviews at the local level (50 families of the Mailuu Suu areas). The Local WG1 in person of Mr. Nemat Mambetov, Sanitary Epidemiological Station (SES)was responsible for the collection of these data. SCK•CEN experts provided the questionnaire and explained the requirements.

WG2: Geostabilisation/hydrogeological monitoring and remediation (works)

WG 2 Projects:

Establishment of a local task force on geostability and hydro(geo)logical Monitoring

This project has been started with introduction to and information of the local WG on tailings and to landslide situation and monitoring by Mr. I. Torgoev (Geopribor) and Mr. A. Meleschko (Ministry of Emergency Situations). This task force assisted in the continuous record keeping of monitoring results obtained and in the protection and maintenance of monitoring equipment, instrumentation and facilities. Monitoring results, changes, deficiencies and new developments

Chapter 5 page 25

have been made available and were communicated to the relevant authorities, administrations and to the representatives of the stakeholders and the public.

The WG2 helped to define the optimum but realistic conditions for an alternative, safe landfill site where the tailings from the deposit might be disposed off if unstable and /or endangered tailings will have to be transferred to an alternative site.

A list of criteria for safe landfill sites has been distributed.

Local costs, time requirements, necessary permits and legal requirements, technical and social feasibility, environmental impacts and potential side effects as well as available local technical capacities have been assessed.

The WG2 also contributed to study the preventive possible measures to avoid the flooding of the upstream area with all detrimental effects for the deposits, flora, fauna and the population. Potential solutions as for instance outlined below have been discussed and ejointly evaluated:

- Escape passages : Taking into account the blockage of the river by slope movements and the subsequent upstream flooding, new passageways might be designed in order to keep traffic, communications, supply of water and energy between the upstream and downstream populations functional. Drinking water pipes, gas and electricity cables must be deviated and protected by encapsulating them in reinforced concrete tubes or displaced along the escape passages . Moreover the Isolit plant opposite to the deposit n° 3 is endangered to be damaged or (partly) destroyed land or block-slides and/or flooding. A decision to transfer the plant has been taken in the meantime .

- Reinforcement of tailings depositories near the river banks by emplacement of gabions at the base of their dams or impoundment confinements.

Local task force on geostability and hydro(geo)logical monitoring

This project was started with introduction to and information of the local WG on tailings and landslide situation and the monitoring by Mr. I. Torgoev (Geopribor) and Mr. A. Meleschko (Ministry of Emergency Situations). This task force assists in the continuous record keeping of monitoring results obtained, provision of information and explanation to locals and in the protection and maintenance of monitoring equipment, instrumentation and facilities. Monitoring results, changes, deficiencies and new developments are made available or communicated on a regular basis to the local WG`s and relevant authorities, administrations and to the representatives of the stakeholders and the public.

WG 2 was involved in evaluations, discussions, assessment-results, designs and comparisons of considered remediation options.

WG3: Involvement of local stakeholders and local awareness

This Working Group engages in the following activities:

- co-ordination of local people/companies/institutions who assisted in

- -the local monitoring and public information campaigns

- -the surveillance of monitoring equipment

- -technical works

- -the establishment of the local awareness network

- Ensuring of efficient and transparent information flow to the population and involvement of the population in the

- -monitoring

Chapter 5 page 26

- -monitoring control

- -stabilisation works

- -remediation works and related cost benefit considerations and

- -decision making process

- This WG provides assurance and continuation of site safety (maintenance of fences and access restrictions) and monitoring after the project closure.

WG3 projects:

Organisation of public meetings involving stakeholders with information on the project objectives, actual status , planned activities and envisaged remedial concepts and options.

With respect to additional work projects in WG 3, it has been suggested by local representatives to publish or publicise the results of the radiological monitoring campaign in the form of a document or booklet issued by the Sanitary Epidemiological Station (SES) of Mailuu Suu for the concerned public ( after approval and in co-operation with the Ministry) .

The Deputy Governor of Mailuu Suu, Mr Ashir Abdullaev, also representative of the Ministry of Emergency Planning, together with Nemat Mambetov, and the Chief Doctor of the Sanitary Epidemiological Station (SES) Dr. Kochkon Aidarov engaged in the local co-ordination of local people/companies/institutions/public bodies/authorities/administrations etc. who :

- assisted in the local monitoring campaign and the surveillance of the monitoring equipment

- assisted in the technical works

assisted in the establishment of a local awareness network and the effective distribution of information .

Chapter 5 page 27