JV GC - WISUTEC
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The Kyrgyz Republic:
Disaster Hazard Mitigation Project (DHMP), Component A
Relocation of TP3 and TP18 to TP6
Conception of the Cover Design for the
New Landfill on Tailings Pond 6
Authors:
U. Barnekow (WISUTEC GmbH / WISMUT GmbH)
M. Roscher (WISUTEC GmbH / WISMUT GmbH)
DATE: NOVEMBER 2007
Disaster Hazard Mitigation Project (DHMP)
Conception of the Cover Design
Relocation of TP03 and TP18 material toTP6
page 2 of 14
Table of Contents
1 INTRODUCTION .......................................................................................................... 3
2 INPUT DATA FOR THE WATER BALANCE CALCULATIONS ................................................. 6
2.1 Geometry data .................................................................................................. 6
2.2 Climate data...................................................................................................... 6
2.3 Data of soil properties of the cover .................................................................... 7
2.4 Data for calculation of runoff ............................................................................. 7
2.5 Vegetation period data ...................................................................................... 8
3 PROPOSED COVER SYSTEM TO BE EVALUATED ............................................................ 9
4 HYDROLOGIC CALCULATIONS ....................................................................................10
5 RESULTS OF THE WATER BALANCE CALCULATIONS ......................................................11
5.1 Results for long-term state (Scenarios 30 and 40) ...........................................11
5.2 Results for the dry period (scenario 31, 32 and 41, 42) ....................................11
5.3 Results for the wet period (scenario 33, 34 and 43, 44) ...................................12
6 CONCLUSIONS REGARDING THE CONCEPTION OF THE COVER DESIGN ..........................13
7 REFERENCES ...........................................................................................................14
List of Annexes
Annex 1:
Table 1: Results of HELP-modelling of the cover designed for the new landfill on
TP 6
Disaster Hazard Mitigation Project (DHMP)
Conception of the Cover Design
Relocation of TP03 and TP18 material toTP6
page 3 of 14
1 Introduction
The Disaster Hazard Mitigation Project – Component A encloses, among other remedial
activities, the relocation of up to approximately 130,000 m3 tailings, radioactively
contaminated soils and mine wastes from tailings pond no. 3 (TP 3) and in addition
approximately 5,000 m3 of tailings, subsoil and mine wastes from tailings pond no. 18 (TP
18) to tailings pond no. 6 (TP 6). The relocated materials shall be disposed into a new landfill
planned to be constructed on TP 6.
The tailings, radioactively contaminated soils and mine wastes disposed in the new landfill
must be covered by a proper surface cover system. The preferable cover system was
evaluated in [1]. Resulting from this evaluation no specific functional requirement was
derived with respect to the acceptable maximum percolation rate through the surface cover
of the new landfill on TP 6. The surface cover must avoid any contact or direct access to the
wastes for people and animals. In addition the cover system is to reduce radon exhalation
rate to an acceptable value. Therefore it was proposed in [1] to evaluate the functionality of a
cost-effective store-and-release-cover (SRC). The use of such a store-and-release cover is
supported by the fact, that with respect to the environmental impact of the new landfill on TP
6 the water pathway was identified in [1] to be of minor concern.
The functionality of a store-and-release cover depends on the geometry of the landfill, the
soil properties of the cover layer and of the underlying layers and on the climate of the
location. The day-to-day water balance of different cover designs were modelled and
evaluated in [2].
This report presents the conception of the cover design for the new landfill on TP 6. As part
of the conception this report presents the results of the water balance calculations applying
the HELP modelling tool (German version 3.80). The model results are used to derive the
design conception for the cover system as a basis for the cover design of the new landfill on
TP 6 presented with [3].
The water balance of a cover system was calculated for the plateau area of the new landfill
inclined ca. 11% and for dam slope area of the new landfill inclined at least 40%.
The cover design process (not withstanding the comments below on the model used) has not
addressed a number of critical areas that must be addressed before it can be implemented,
they are:
1. Clearly defined and measurable performance objectives have not been set for the
cover system. Without these it is not possible to design an appropriate cover system
for TP6. For example; what is the maximum nett percolation amount that will be
acceptable while achieving performance objectives? All of the design objectives
should be clearly stated and be measurable.
2. Page 9 of the EIA states that “… the stability of the waste disposal solution shall be
ensured over a period of 1000 years, but at least 200 years.”. The cover design
provides no evidence of this as having been a design objective.
Disaster Hazard Mitigation Project (DHMP)
Conception of the Cover Design
Relocation of TP03 and TP18 material toTP6
page 4 of 14
3. Whilst there have been geotechnical dam stability calculations (discussed elsewhere)
undertaken for TP6, the issue of containment from an erosion impacts perspective
has not been addressed. Typically this would require some form of landform and
erosion modelling. Given the objective stated in the EIA this is a critical oversight.
4. The life of performance of the cover system has not been demonstrated, ie; will the
required performance objectives (nett percolation etc) still be met 200 years after
construction?
5. Monitoring – the Monitoring and Radiation Protection Plan does not address postconstruction performance monitoring of the cover system. Without ongoing post
construction monitoring how can it be demonstrated that;
a. the cover system is performing as designed
b. the performance is being maintained over time,
Performance monitoring will also give early warning if the performance is
deteriorating and allow time to plan and implement corrective actions if required.
6. Overall there are a number of items in the cover design report and other
documentation referring to the cover design and construction that require explanation,
examples include:
a. Why is the store and release cover layer (that above the 50cm compacted
barrier layer) being applied in nominal 50cm layers with track rolling (two
passes of a dozer) on each layer and that the erosion resistant layer is
specified as requiring compaction with a sheepsfoot roller. All of these
activities are inconsistent with construction of a store and release cover
system.
b. The specifications require a compacted 50cm layer at the base of the cover
system to “…we recommend to compact the lower 50cm thick part of this
layer.” By compacting this layer it no longer is a part of the store and release
cover system, but instead is intended to function as a barrier layer below the
store and release layer. The cover modelling reviewed is based on a cover
with a total thickness of 200 cm, however, if the bottom 50 cm is a compacted
barrier layer then the cover thickness is only 150 cm.
c. The cover design documentation makes the following statement, “In order to
avoid any relevant upward pore water flow during long dry periods of intensive
evapotranspiration we recommend to compact the lower 50 cm thick part of
this layer.” This 50cm layer referred to consists the bottom 50cm of 200cm of
material placed on TP3, however, in Appendix 1 the evaporative zone depth
for all scenarios modeled is only 60 cm.
d. Changes in properties of the barrier layer over time and their consequent
impacts on performance do not appear to have been addressed.
Disaster Hazard Mitigation Project (DHMP)
Conception of the Cover Design
Relocation of TP03 and TP18 material toTP6
page 5 of 14
e. No information has been supplied on the types of testwork undertaken on the
proposed cover material, nor have the number of samples taken or their
locations been provided.
7. Throughout this project there have been a number of references to the use of
International Best Practice (IBP), the PoE does not consider that the use of the HELP
model to design the cover system any longer represents IBP. A number of reasons
supporting this view are provided following, the PoE would appreciate a written
response to these comments.
a. It appears that the materials properties have been to represent a change
resulting from weathering factors (wet-dry, freeze-thaw, etc.). If this is the
case, and because HELP can’t do a bi-modal SWCC or k-function, then they
have overestimated evaporation rates because while the infiltration capacity
increases by altering the functions due to weathering, with only uni-modal
functions, so does the rate that water can move out of the profile for
evaporation. Hence, for dry climate conditions, net percolation rates are
typically under estimated.
b. In HELP the user inputs an evaporative zone depth, which controls the depth
over which daily evaporation is drawn from the profile. Hence, a model
prediction can be completely changed by changing the evaporation zone input
value in HELP. At the least this variable must be a key part of the sensitivity
anaylsis as it has a controlling influence on the predicted water balance.
There must be a realization that HELP, by using this approach, goes out of its
way to de-couple soil-atmosphere interaction (which was the key
advancement in modelling by the introduction of the SoilCover and Unsat-H
models, and continues with the Vadose/W model).
c. The user inputs a CN-value, which control RO partitioning. As with the above,
at the least it needs to be a sensitivity variable as this as a controlling
influence on the predicted water balance.
d. There must be variability of not only climate conditions within the database as
has been done, but also of the database itself given that the climate data
came from a number of sources (none close to the site). This is a key
component of the sensitivity modeling that is missing.
e. There must be variability in the actual material properties modelled, both
before and after the assumed impact on material properties due to
weathering. How can this not be the case given that the borrow source will
most likely be variable. Also, how many samples were collected to determine
the material properties (i.e. what is the basis), and what lab tests were
conducted (i.e. SWCC and Ksat testing, or were the PSDs only collected and
then assume default material properties in HELP?).
f.
The approach to predicting performance must be on the basis of probability,
not a deterministic approach. For example, what is the probability that radon
Disaster Hazard Mitigation Project (DHMP)
Conception of the Cover Design
Relocation of TP03 and TP18 material toTP6
page 6 of 14
egress will be greater than the standard? What is the probability that nett
percolation will be greater than the design criteria? Rather than average net
percolation is X%. Then, for different designs you can get a feel for what level
of risk is being taken on versus the cost of that cover alternative.
Input data for the water balance calculations
The HELP-model needs consistent and complete data sets to model the day-to-day water
balance of the soil layers. The required datasets are listed below:
1. Geometry/design data of the landfill site (area of the landfill site, slope
inclination of plateau and dam slope surfaces, slope length, design of the
cover system, "curve number value" (CN-value) for calculation of the runoff
applying the SCS-method
2. Climate data (precipitation, air temperature, wind speed, humidity, solar
radiation)
3. Soil physical properties (porosity, field capacity, plant-available field
capacity, hydraulic conductivity)
4. Vegetation data (growing season start and end day, maximum leaf area
index, evaporative zone depth)
2.1
Geometry data
The geometry of the new landfill surface area was implemented from [3]. The transverse
slope inclination of the plateau surface is 5%. The longitudinal slope inclination of the plateau
surface is ca. 13%. Consequently the resulting slope is approx. 11%. The average slope
length of the plateau surface was estimated to be 115 m. The plateau area covers 2.0
hectare. The slope inclination of the dam slope area is 40%. The average slope length of the
dam was estimated to be 50 m. The dam slope area covers nearly 0.85 hectare. The entire
cover surface of the new landfill on TP 6 encloses nearly 2,85 hectare.
2.2
Climate data
Climate data for the region of Mailuu Suu were not available. Therefore the data of the
nearest weather station located in Jalal-Abad were used. This weather station is located on a
similar altitude like Mailuu-Suu. Like Mailuu-Suu Jalal-Abad is located at the northeastern
border of the Fergana valley. Therefore the climate data of both locations can be estimated
to be comparable.
The following climate data of this weather station have been available for the period 20012005 as listed below:
Disaster Hazard Mitigation Project (DHMP)
Conception of the Cover Design
Relocation of TP03 and TP18 material toTP6
page 7 of 14
-
daily sums of precipitation
-
daily average values of the air temperature
-
daily average values of the wind speed
-
monthly average values of the humidity.
No data have been available regarding the solar radiation. Therefore the solar radiation data
were estimated based on climate data of a comparable climate station at a similar latitude
like the latitude of Mailuu Suu. Finally the solar radiation data used for the HELP-modelling
were generated based on the measured daily sums of precipitation for Jalal-Abad and on the
climate data of the meteorological station in Northplatte, USA.
In addition the measured period of available climate data for Jalal-Abad is very short.
Therefore the applicability of the results of the water balance modelling applying HELP must
be seen to be limited. Usually the series of climate data used for such water balance
calculations shall enclose a period of at least 20 years.
Therefore the available short climate data series available from the meteorological station at
Jalal-Abad for the period of 2001 till 2005 were added to series of 20 years. The
implementation of such added data rows allowed to get results of the HELP-modelling
applicable for cover designing.
2.3
Data of soil properties of the cover
Soil data of the cover material were taken directly from the available data or derived based
on the available soil property data. In addition soil samples were taken from different
locations in the area of Mailuu Suu to get data from the potential cover material for the new
landfill on TP 6. The soil samples were analyzed to estimate the soil type and soil properties
of the available cover material.
Potential cover material is located near TP 6 and can be classified in average as a clayey silt
soil. The soil parameters of this potential cover material depends on the bulk density of the
soil after placement of the respective surface cover. The bulk density immediately after the
construction change with time to the long term. Therefore both scenarios were modelled the
short term state immediately after construction and the long term state of the cover. The
physical soil properties used for both scenarios are shown in table 1 (Annex 1).
2.4
Data for calculation of runoff
The HELP-model needs a curve number value for the calculation of the runoff. The cover soil
curve number values ("CN-values") for the calculations were estimated based on experience
from HELP-modelling on other sites. The CN-values of the cover from TP 6 depends on the
type of use and the surface slope. For the calculations on the plateau surface we used a CNvalue of 80,9. On the dam surface we implemented a CN-value of 82,3.
Disaster Hazard Mitigation Project (DHMP)
Conception of the Cover Design
Relocation of TP03 and TP18 material toTP6
page 8 of 14
2.5
Vegetation period data
The growing season's start and end day could be determined with respect to the air
temperature. As a boundary condition the first day of a year with an air temperature above
0°C was the first day of the growing season (here: February, 24th). The last day of the year
with an air temperature below 0°C was the end of the growing season (November, 27th).
Disaster Hazard Mitigation Project (DHMP)
Conception of the Cover Design
Relocation of TP03 and TP18 material toTP6
page 9 of 14
3 Proposed cover system to be evaluated
Resulting from the evaluation of different cover systems we proposed a preliminary cover
design for the plateau area and for the dam slope area with [2].
Resulting from the evaluation of the climate data (heavy precipitation rates) and of the soil
data of the available cover materials we concluded in [2] that it is necessary to additionally
plan for erosion protection measures on top of the proposed surface cover system of the new
landfill on TP 6. We recommend herewith to build an erosion protection layer on the top of
the store-and-release cover on both the plateau area and the dam slope area. This layer
shall be 50 cm thick. It shall consist of a mixture of coarse-grained gravel-pebble material
and fine-grained material. The sizing of proper coarse- and fine-grained materials depend on
the slope inclination.
The erosion protection layer is underlain by the store-and-release cover proposed with [2].
The required minimum thicknesses of this store-and-release cover were evaluated in [2]. The
results of the calculations presented with [2] were used to optimize the design for the cover
system on the plateau surface and the dam slope. Resulting from [2] and implementing the
required erosion protection layer presented above the day-to-day water balance of the
following cover designs were calculated in this report:
Plateau surface:
On the plateau surface we calculated the day-to-day water balance of a cover with a total
thickness of 2.0 m.
The upper 50 cm will be built as an erosion protection layer consisting of 50% of coarsegrained material (gravel-pebble mixture 80/150) and 50% of sandy-loamy soil.
Under the erosion protection layer we propose to place a 150 cm thick store-and-release
layer.
In order to avoid any relevant upward pore water flow during long dry periods of intensive
evapotranspiration we recommend to compact the lower 50 cm thick part of this layer.
Dam slopes:
On the dam slopes we calculated the day-to-day water balance of a cover of in total 1.5 m
thickness.
The upper 50 cm layer of the cover shall be an erosion protection layer. The amount of
coarse-grained material (gravel-pebble mixture) of this layer should be 50%, the amount of
sandy loamy soil shall be about 50%.
The erosion protection layer shall be underlain by a single 1.0 m thick storage layer. This
layer shall not be compacted.
Disaster Hazard Mitigation Project (DHMP)
Conception of the Cover Design
Relocation of TP03 and TP18 material toTP6
page 10 of 14
4 Hydrologic calculations
The day-to-day water balance was calculated applying the HELP-model for the two cover
designs presented with chpt. 3. Only the climate data (dry period, wet period, 20 years
period) and the soil properties (short term state immediately after construction and long term
state) were modified for the different scenarios.
At first we calculated the day-to-day water balance for the two types of the cover design for a
period of 20 years. Because of the available short data series the values of Jalal-Abad for the
period of 2001 till 2005 were added to series of 20 years (chapter 2.2). The soil properties of
the different layers are depending on the bulk density in situ. Therefore we implemented the
bulk density immediately after construction phase for the first five years of the calculation.
The soil properties for a the bulk density in the estimated long-term state were used starting
from the 6th year of calculation till the end.
Scenario 30 and 40 represent the water balance calculation of the cover on the plateau
surface and the dam slope area for a period of 20 years.
Secondly we calculated the day-to-day water balance for a dry period. This dry period is an
estimation with respect to the driest year of the period 2001 to 2005. The driest year 2001
was added to five years period. The day-to-day water balance of the cover was calculated for
such a dry period implementing the soil properties for both scenarios the state immediately
after the construction and the long-term state. Scenario 31, 32 and 41, 42 represent the
water balance calculations of the cover on the plateau surface and the dam slope for the dry
period.
At last we calculated the day-to-day water balance for a wet period. This wet period is an
estimation with respect to the wettest year of the period 2001 to 2005. The wettest year 2003
was added to five years period. The day-to-day water balance of the cover was calculated for
such a wet period implementing the soil properties for both scenarios the state immediately
after the construction and the long-term state. Scenario 33, 34 and 43, 44 represent the
water balance calculations of the cover on the plateau surface and the dam slope for the wet
period.
The detailed input data used for the hydrologic calculations are shown in table 1 (Annex 1).
Disaster Hazard Mitigation Project (DHMP)
Conception of the Cover Design
Relocation of TP03 and TP18 material toTP6
page 11 of 14
5 Results of the water balance calculations
The modelling results for all scenarios are listed in detail in table 1 (Annex 1).
5.1
Results for long-term state (Scenarios 30 and 40)
Scenario 30 and 40 include the hydrologic calculations of the cover for the period of 20
years.
Table 1 (Annex 1) shows that on the plateau surface (scenario 30) the percolation through
the cover has been calculated to be around 31 percent of the annual precipitation rate. Most
of the remaining 65 percent of the annual precipitation rate will evaporate. Only a little part of
the precipitation will run off on the surface (ca. 4%). The change in water storage of the cover
layer is nearly constant for this scenario.
Sceanrio 40 represents the designed cover on the dam slope. According to the steeper slope
the runoff rate on the dam slope is calculated to be 10% of the precipitation rate. Only 57
percent of the annual precipitation rate evaporate. The percolation rate slightly increases on
the dam surface by 2 percent. The reason for this increment is the lacking lowest compacted
layer and the permeable dam body underlying the cover.
The calculation results of these scenarios can be seen as representative for the two different
cover designs. With regrad to the climate data we determined a percolation rate of about
30% of the annual precipitation rate. This percolation rate is acceptable because no specific
requirements regarding the maximum percolation rate are needed acc. to [1].
5.2
Results for the dry period (scenario 31, 32 and 41, 42)
Scenario 31 and 41 include the hydrologic calculations of the cover for the dry period for
both the plateau surface and the dam slope area with respect to the short term state
immediately after construction.
Scenario 32 and 42 include the hydrologic calculations of the cover for the dry period for
both the plateau surface and the dam slope area with respect to the long term state.
Both the calculation for plateau surface and the calculation for the dam slope area show
comparable results. During the period after construction the annual runoff will be larger than
for the long-term state for both areas. On the plateau surface the runoff was calculated to be
13% and on the dam slope area 33% of the annual precipitation rate for the state after
construction. For the long-term state the runoff will decrease to 1%…2% for both the cover
on the plateau area and on the dam slope area.
The time-dependent development of the evapotranspiration rate also depends on the bulk
density of the cover material. Immediately after construction phase the evaporation rate was
calculated to be 60% of the annual precipitation rate on the plateau area and 48% of the
annual precipitation rate on the dam slope area. In the long-term state the evapotranspiration
rate will increase to 66 or 56 percent respectively.
Disaster Hazard Mitigation Project (DHMP)
Conception of the Cover Design
Relocation of TP03 and TP18 material toTP6
page 12 of 14
The percolation rate will increase from the short-term to the long-term state on both areas.
Especially on the dam slope area the percolation rate will increase significantly in the longterm state (46% of the annual precipitation rate). The reason is the estimated increase of the
hydraulic conductivity of the cover material to the long term.
The HELP-modeling shows that the during the summer months of the dry period the water
content of the evaporative zone of the cover system will be near the welting point. This could
result in temporary stress for the vegetation on the cover system. Therefore the cover is to
be vegetated by seeding sorts of grass adopted to the regional climate conditions.
5.3
Results for the wet period (scenario 33, 34 and 43, 44)
Scenario 33 and 43 include the hydrologic calculations of the cover for the wet period for
both the plateau surface and the dam slope area with respect to the short term state
immediately after construction.
Scenario 34 and 44 include the hydrologic calculations of the cover for the wet period for
both the plateau surface and the dam slope area with respect to the long term state.
The results for scenario 33 and 34 presented with table 1 (Annex 1) show evapotranspiration
rates of 57% and 59% of the annual precipitation rate. The time dependent development of
the runoff on the plateau surface for the wet period is comparable with scenario 31 and 32.
On the plateau surface the annual runoff reduces from 11% immediately after construction to
2% of the annual precipitation rate in the long term state. According to the decreasing runoff
the percolation rate is increased from the construction state till the long-term state on the
plateau surface by 6%.
The results for scenario 43 and 44 presented with table 1 (Annex 1) show an
evapotranspiration rate of 51% and 55% of the annual precipitation rate. The runoff and the
percolation rate are the only two parameters that will change time dependently to the long
term. The runoff decreases from the construction state to the long-term state from 40 to 1
percent of the annual precipitation rate. The percolation rate will increase at comparable
values because of increas of the hydraulic conductivity for the cover material to the long
term.
The HELP-modeling shows that the during the summer months of the wet period the water
content of the evaporative zone of the cover system will be near the welting point, particularly
from June till September. This could result in temporary stress for the vegetation on the
cover system. Therefore the cover is to be vegetated by seeding sorts of grass adopted to
the regional climate conditions.
Disaster Hazard Mitigation Project (DHMP)
Conception of the Cover Design
Relocation of TP03 and TP18 material toTP6
page 13 of 14
6 Conclusions regarding the conception of the cover design
The water balance of the evaluated cover system of the new landfill on TP 6 depends on
different factors:

The climate in the area of Maillu Suu is very variable. During winter and spring the
average monthly precipitation rate is quite high. During the summer months (June till
September) the average monthly precipitation rate is very low. In average a
precipitation sum from June till September is only 30 mm. This could result in
temporary stress for the vegetation on the cover system. Therefore the cover is to be
vegetated by seeding sorts of grass adopted to the regional climate conditions.

The time dependent development of the bulk density of the cover material from the
stage immediately after construction to the long term significantly influences the water
balance of the surface cover. Immediately after the construction of the cover system
the bulk density is quite high. With time the bulk density will decrease due to rooting,
weathering and bioturbation. The decrease of the bulk density leads to an increase of
hydraulic conductivity thus increasing the percolation rate to the long term.
Resulting from the hydrologic calculations we conclude that the evaluated cover design
conceptions presented with chpt. 3 meet the requirements of the surface cover as defined in
[1]. The conceptions of the cover designs are presented below:
Plateau surface:
On the plateau surface we propose a cover with a total thickness of 2.0 m consisting of (from
top to bottom):

a 50 cm thick erosion protection layer consisting of a mixture of 50% coarse-grained
gravel-pebble mixture (sizing 80/150 mm) material and 50% sandy-loamy soil.

a 150 cm thick store-and-release layer. During construction phase the 150 cm
storage-and-release layer shall be build by placing three layers of ca. 50 cm each. In
order to avoid any relevant upward pore water flow during long dry periods of
intensive evapotranspiration we recommend to compact the lowest 50 cm thick
sublayer.
In addition, erosion protection measures have to be planned as part of the design phase with
respect to the short term (initial phase after construction) and to the long term (after
vegetation will have developed).
Dam slopes:
On the dam slope area we propose to construct a cover with a total thickness of 1.5 m
consisting of (from top to bottom):

a 50 cm thick erosion protection layer consisting of a mixture of coarse-grained
(gravel-pebble mixture) material and fine-grained material. The coarse-grained
material (gravel-pebble mixture: 80/150 mm) should be 50% as well as the sandyloamy soil.
Disaster Hazard Mitigation Project (DHMP)
Conception of the Cover Design
Relocation of TP03 and TP18 material toTP6
page 14 of 14

a 100 cm thick store-and-release layer. With regard to hydrological aspects a certain
compaction degree of the storage layer is not specified. We recommend to compact
the layer by at least 2 passes of the dozer everywhere to achieve sufficient ersosional
stability.
Before placing the SR-layer an at least 0.75 m thick layer consisting of coarse-grained waste
dump materials shall be placed in the upper part of the dam body. If possible the entire dam
body should be built of coarse-grained waste dump material.
As part of the design further erosion protection measures, like i.e. ditches, must be planned
for to avoid unacceptable erosion of the cover surface.
7 References
[]
[2]
[3]
JV GC – WISUTEC: The Kyrgyz Republic: Disaster Hazard Mitigation Project
(DHMP), Component A. Feasibility study - Remediation of Tailings Pond # 3
(Subcomponent A6), September 2006.
WISUTEC GmbH / WISMUT GmbH: The Kyrgyz Republic: Disaster Hazard
Mitigation Project (DHMP), Component A: Evaluation of Cover Designs for
the Landfill to be constructed on Tailings Pond 6 - Design Principles for Store
& Release Cover (SRC).- Chemnitz, January 2007
JV GC – WISUTEC: Kyrgyz Republic: Disaster Hazard Mitigation Project
(DHMP); Relocation of TP 03 and TP 18 material to TP 06, Working Design,
Explanatory Notes, November 2007
Disaster Hazard Mitigation Project (DHMP)
Conception of the Cover Design
Relocation of TP03 and TP18 material toTP6