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CROW BUTTE PROJECTSOLAR EVAPORATION POND

ENGINEERING DESIGN REPORT

April 27, 1988

Prepared For:

Ferret Exploration Company ofP.O. Box 169

Crawford, Nebraska

Nebraska, Inc.

69339

Prepared By:

Western Water Consultants,P.O. Box 3016 701 Antler DriveSheridan, WY Casper, WY82801 82601

Inc.P.O. Box 4128Laramie, WY82071

OFFICIAL: DOCKET COPY J.A9508210055 880523 /PDR ADOCK 04008943

PC PDR ~6O

TABLE OF CONTENTS

Page

1.0 INTRODUCTION .............................................. 1

2.0 DESCRIPTION OF DESIGN...................................... 2

2.1 Site Layout ........................................... 22.1.1 Location and Dimensions......................... 22.1.2 Surface Drainage................................ 2

2.2 Hydraulic Capacity .................................... 42.2.1 Operating Levels and Reserve Capacity ........... 42.2.2 Freeboard Capacity ............................. 7

2.3 Synthetic Membrane Liners....................82.3.1 Membrane Liner Otos.................82.3.2 Applicability of Specified Lining Materials ...... 92.3.3 Gas Venting.................................... 102.3.4 Liner Installation............................. 10

2.4 Leak Detection ....................................... 112.4.1 Optional Systems...............................1.12.4.2 Single Liner OptionA .......................... 112.4.3 Double Liner Option B........................... 14

3.0, GEOTECHNICAL INVESTIGATION................................. 16

3.1 Field Investligation................................... 163.2 Laboratory Analyses................................... 163.3 Slope Stability Analysis.............................. 18

4.0 CONSTRUCTION SPECIFICATIONS AND QUALITY ASSURANCE ...........19

4.1 Specifications ....................................... 194.2 Engineer Supervision .................................. 224.3 Quality Assurance .................................... 22

5.0 EVAPORATION POND OPERATION................................. 23

5.1 Wastewater Characteristics and Piping Details .......... 235.2 Operational Monitoring................................ 255.3 Maintenance........................................... 255.4 Fencing.............................................. 26

6.0 REFERENCES................................................ 26

APPENDICES

APPENDIX A. 10 Sq. Mi. 6-Hour PMP Flood Studies .................28

APPENDIX B. Geotechnical Test Hole Logs ........................ 29

APPENDIX C. Soil Lab Test Results, Braun Engineering ............30

APPENDIX D.. Construction Specifications ........................ 31

i

TABLE OF CONTENTS (Continued)

Page

LIST OF TABLES

Table 1. Drainage Basin Parameters and Calculated Runoff forthe 10 Sq Mile 6-Hour PMP ..............................

Table 2. HEC-2 Computerized Flood Study Results for the PMF .....

Table 3. Soil Engineering Test Results for the Pond 2 CompositeSample .................................................

LIST OF FIGURES

Figure 1. Solar Evaporation Pond Slope Stability Analysis(2H:IV Inside Slopes) .................................

Figure 2. Solar Evaporation Pond Slope Stability Analysis(2.5H:IV Outside Slopes) ..............................

Figure 3. Typical Solar Evaporation Pond-Plant Building PipingDetail ................................................

LIST OF MAPS

Map 1. Solar Evaporation Pond Location Map

Map 2. Solar Evaporation Pond Site Layout

Map 3. Solar Evaporation Pond Cross Sections (2 Sheets)

Map 4a. Solar Evaporation Pond Detail (Single Liner Option)

Map 4b. Solar Evaporation Pond Detail (Double Liner Option)

ii

5

6

17

20

21

24

CROW BUTTE PROJECT SOLAR EVAPORATION POND ENGINEERING DESIGN REPORT

1.0 INTRODUCTION

This report presents detailed design information and the results of

engineering studies which form the basis for the design of five solar

evaporation ponds at Ferret Exploration Company of Nebraska's Crow Butte

in-situ uranium project southeast of Crawford, Nebraska. This report

and the design presented herein were prepared by Western Water

Consultants, Inc. under the direct supervision of Mr. Paul Rechard,

Nebraska P.E. No. E-6477.

The solar evaporation ponds discussed in this report have been

designed to meet the requirements of the U.S. Nuclear Regulatory

Commission Regulatory Guides 3.11 and Staff Position Paper #WM-8101.

The design was also developed to comply with the requirements of the

Nebraska Department of Environmental Control, specified in Title 123.

Designs are presented herein for solar evaporation ponds equipped

with membrane liners and leak detection systems. Two optional pond

lining and leak detection systems are presented in this report in order

to allow the applicant some flexibility in determining the most cost

effective system prior to construction. Detailed design information is

presented for each optional plan in this report. The two optional plans

are considered environmentally equivalent in that each is designed to

meet the requirements of the regulatory agencies discussed above.

Evaporation pond construction will be staged in consideration of

the time-dependent storage and evaporation requirements of the proposed

mining and restoration activities. Ponds 1 and 2 will be constructed

first and will constitute the only ponds to be operated during the

I

initial mining phase (years 1-3). The remaining ponds (Ponds 3, 4 and

5) will be constructed to be operational by year 4, when inflows are

expected to increase due to restoration activity in the initial well

field locations.

2.0 DESCRIPTION OF DESIGN

2.1 Site Layout

2.1.1 Location and Dimensions

The general location of the solar evaporation ponds is shown on Map

1 and a detailed plan is presented on Map 2. The commercial pond site

is in an area adjacent to the ore body and the five rectangular ponds

will be placed with their longest direction parallel to the topographic

slope to optimize earthwork and to insure adequate drainage of surface

runoff. Map 3, sheets 1 and 2 of 2, present the pond cross sections and

dimensions. In order to accommodate topographic and drainage

conditions, the evaporation pond system is composed of two types of

ponds with different geometries. Ponds 1, 2 and 5 have similar

dimensions, with bottom dimensions of 850 ft x 200 ft, while Ponds 3 and

4 are slightly wider and shorter, with bottom dimensions of 700 ft x 250

ft. Each pond is 15 feet deep from the crest to the toe of the side

slope and the floor of each pond slopes at a uniform 2 percent inward,

toward the longitudinal axis. Pond embankments have crest widths of 10

feet, inside slopes of 2H:1V and outside slopes of 2.5H:IV.

2.1.2 Surface Drainage

The evaporation ponds have been designed to prevent the capture of

surface runoff. Runoff control ditches will intercept and convey runoff

2

away from the ponds into adjacent drainages. The location and design of

the collector ditches are illustrated on Map 2. The runoff control

ditches will be constructed as V-ditches with minimum depths of 3 feet

to insure adequate capacity. The uphill dikes of the evaporation ponds

are all within approximately 700 feet of the drainage divide (see Map

1), and the maximum area estimated to drain to the head of the ditch

east of Pond 2 is about 5 acres. With a ditch slope of 0.005 ft/ft and

a calculated peak discharge for the 6-hour PMP of 70 cfs, the ditch,

near the head, would flow at a depth of about 2.9 ft., assuming a

roughness coefficient of 0.03. The contributing drainage area increases

to about 15 acres at the mouth of the ditch on the southeast corner of

Pond 2 and the calculated 6-hour PMP discharge is 208 cfs corresponding

to a flow depth of 4.3 feet at this point. The runoff control ditch at

the southeast end of Pond 2 will be at least 4.5 feet in depth and the

proposed ditch cross sections will be adequate to convey runoff around

the pond embankments. The summary sheets for these runoff calculations

are included in Appendix A of this report.

A flood study was conducted to evaluate the capacity of the

drainageway between Pond 5 and the remaining ponds. The 6-hour probable

maximum precipitation (PMP) was used as the design storm for the flood

study. The PMP was determined according to the method described by

Hydrometeorological Report No. 55 (NOAA, 1984). According to Plate Vb

of the report, the study area is located in a minimum orographic region,

and using Figure 11.6 (Depth-Area-Duration Curves) results in a 10

square mile 6-hour PMP of 23 inches. This PMP is an extremely

conservative design rainfall which is nearly 1.5 times the PMP

3

calculated for the same location using the methodology previously/

recommended by the USBR (USBR, 1973).

The PMP rainfall was used to calculate the probable maximum flood

(PMF) using the verified rainfall/runoff computer program TRIHYDRO (WWC,

1986) which utilizes the triangular hydrograph procedure as recommended

by the SCS and *USBR (1973). Table 1 presents the drainage basin

parameters, rainfall, runoff and peak discharge calculated to result

from the 6-hour PMP. A summary output of the computerized runoff

calculation is included in Appendix A.

The peak discharge calculated for the PMP was used for input into

the U.S. Army Corps of Engineers HEC-2 (U.S. Army COE, 1986) computer

program for the determination of water surface profiles. The computed

flood boundary for the 6-hour PMF is shown on Map 2. Table 2 summarizes

the results of the HEC-2 study. The results of the HEC-2 computer study

show that for all cross sections the crests of the pond embankments are

at least 7 feet above the computed water surface elevation of the PMF.

As this study documents, the drainageway between the ponds has the

capacity to convey the 6-hour PMF without any danger of overtopping the

encroaching embankments.

2.2 Hydraulic Capacity

2.2.1 Operating Levels and Reserve Capacity

The evaporation ponds have been sized to provide storage and

evaporative surface for wastewater generated by mining and restoration

activities at the Crow Butte Project. The capacity of the ponds to

store and evaporate wastewater will be augmented by the use of various

techniques such as inflow dispersion manifolds to enhance evaporation.

4

Table i. Drainage Basin Parameters and Calculated Runofffor the 10 sq mile 6-Hour PHP

DRAINAGE BASIN PARAMETERS

Drainage Unit:

Drainage Area:

Hydro. Soil Type:

Stream Length:

Elev. Difference:

Runoff Curve No:

Minimum Inf. Loss:P.

Precipitation:

Subarea A

0.06 sq ml

Group B

0.4 ml

80 ft

69

14 iph

23 in

2.COMFUTED HYDROGRAPH VALUES

Peak Discharge: 517. 78 cfs

Runoff Volume: 92.68 ac-ft

Time to Peak: i0.02 hr

Notes: i. The 6-Hour PMP was determined from HMR No. 55(NOAA, 1984) with no areal adjustment.

-2. Runoff and peaR discharge were determined byTRIHYDRO (WWC, 1986), a computerized version ofthe triangular hydrograph procedure asrecommended by the SCS and USBR (USBR, 1973).

5

Table 2. HEC-2 Computerized Flood Study Results for the PMF

CrossSection

No.

ComputedWater SurfaceElevation

(ft-msl)

MeanChannel

Velocity(fps)

FlowArea

(sq ft)Depth(ft)

0+002+004+005+056+008+05

10+7011+5511+7512+7014+7516+7518+7520+3021+3522+4023+2524+1025+4026+1527+6529+05

3844.893851. 253854. 683858. 553859. 363864. 713867.743869. 703870.073873. 033876. 333879.463881. 813884. 203885.063886. 523888. 653891. 303894.683897. 873902. 553907.40

4.895.743. 554. 172. 574.683.996.075. 905. 506. 146.084.426. 171. 394.054.394.994. 685. 294. 144.79

106.0090.23

145. 86124. 21201. 40110.69129. 91

85. 3687. 7994. 2284. 3285. 15

117. 1783.90

373. 79128.06118.00103.74110. 63

97. 98124. 98108. 16

0. 891. 250.680.551. 360.711.741. 702.071. 032. 331. 461. 812.203. 060. 520.651. 300.680. 870. 551. 40

Note: i. The cross section locationsare shown on Map 2.

and flood boundaries

6

The capacities and operating levels of the evaporation ponds are shown

on Map 3, sheet 1 of 2. Although the pond system includes ponds of two

different geometries, the maximum and operating capacities of the two

types of ponds are nearly identical. During the initial phase of

commercial operation (years 1-3) only two ponds will be required to

contain wastewater generated during mining. Therefore, the applicant is

proposing to construct only Ponds 1 and 2 initially. These ponds will

be operated at a maximum water level of seven (7) feet during the first

three years of operation. This will provide an adequate reserve

capacity for the contents of either pond to be transferred to the other,

should the need arise.

The remaining ponds (3, 4 and 5) will become operational beginning

in year 4 when wastewater inflows are expected to increase due to

restoration activities. When at least three ponds are operational,

starting in year 4, the operating level of each will be increased to 10

feet. The increased operating level will still provide adequate reserve

capacity for dewatering any one pond into the other two if the need

should arise. The volume calculations and emergency capacity

calculations for the evaporation pond system for the phases of operation

are shown on Map 3, sheet 1 of 2. During all operational phases reserve

capacity will be maintained in the pond system to allow the dewatering

of the contents of any one pond if it becomes necessary.

2.2.2 Freeboard Capacity

Under operational conditions, a freeboard of at least 5 feet will

be maintained between the crest of the embankments and the operational

water level. This freeboard is adequate to contain the runoff from the

7

probable maximum precipitation over the catchment area of the pond

(equivalent to 25 inches) and the wave runup calculated to occur from

the 2-year wind speed of 60 mph over the longest fetch of the pond

surface (1.1 foot) with an additional 1.8 feet of freeboard remaining as

a safety factor. The freeboard capacity of each pond is also adequate

to contain at least one-half of the operating capacity of any one pond

to allow the dewatering of a pond into two of the other ponds if it

should become necessary.

2.3 Synthetic Membrane Liners

2.3.1 Membrane Liner Options

Two design options are presented for the solar evaporation ponds at

the Crow Butte Project. The optional designs will allow the applicant

the choice of determining the most cost effective system prior to

construction. The options differ in the design of the pond bottom liner

and leak detection systems, although both meet the applicable regulatory

requirements. Option A consists of side slopes lined with a double

synthetic membrane with geonet installed between the liners for

transmitting potential leakage. A single synthetic liner would be

placed on the pond bottom, underlain by leak detection sand and piping,

over a compacted foundation. The detailed design of Option A is

illustrated on Map 4a, Solar Evaporation Pond Detail (Single Liner

Option).

Under Option B, the entire pond interior, both sides and bottom,

would be lined with two synthetic membrane liners with geonet and leak

detection piping installed between the liners. The detailed design of

Option B is illustrated on Map 4b, Solar Evaporation Pond Detail (Double

Liner Option).

8

Both pond design options include inside slopes overlain with two

synthetic membrane liners. The double lining system will consist of a

primary geomembrane (uppermost synthetic liner) with a geonet between

the two liners to convey leakage to the detection pipes and a secondary

geomembrane (lowermost liner). The single liner used on the pond bottom

in Option A will consist of one liner (primary geomembrane) which will

be underlain by leak detection sand and a compacted soil foundation.

Synthetic liners to be used in the construction of the solar

evaporation ponds will include the following materials:

Primary Geomembrane (both options):

36 mil HYPALON (TM) or60 mil high-density polyethylene (HDPE)

Geonet (Option A (sides only) and Option B):

high-density polyethylene (HDPE)

Secondary Geomembrane (Option B):

20 mil polyvinyl chloride (PVC)

The physical properties and detailed specifications of the proposed

lining materials areý presented in Appendix D, Construction

Specifications.

2.3.2 Applicability of Specified Lining Materials

The use of a HYPALON or HDPE primary geomembrane will provide a

puncture and tear resistant inner liner that is resistant to photo and

chemical degradation. Both materials have been used extensively in this

type of application, and their performance in the containment of both

hazardous and nonhazardous wastes is well documented. Geonet will be

used to provide a porous, highly transmissive media for the rapid

9

transport of potential leakage to the leak detection system. The geonet

is also constructed of HDPE and is, therefore, highly resistant to

biological and chemical deterioration.

The use of a PVC underliner (secondary geomembrane) will provide a

cost-effective barrier to the small amount of infiltration that could

potentially occur if a leak should develop. Although PVC is highly

resistant to deterioration from the chemical constituents of the in-situ

wastewater, it is susceptible to damage from ultraviolet light. The use

of PVC for only the lowermost liner will avoid problems in this regard

since the PVC will not be exposed to sunlight in this application.

Specifications and physical properties of the proposed lining materials

are presented in Appendix D, Construction Specifications.

2.3.3 Gas Venting

To reduce the potential of gas accumulation under the pond liners,

the ponds have been designed with bottom slopes of two percent toward

the longitudinal axis from the toe of the side slopes (see Map 3, Sheet

1 and 2 of 2). This bottom slope will help to convey any gas which

collects under the liner toward the side slope and up to gas vents which

will be installed every 50 feet along the crest of the pond embankments

as shown on Maps 4a and 4b. The gas vents will also serve to balance

air pressures above and below the liner, reducing the potential for

billowing and air-foil effects when the ponds are empty.

2.3.4 Liner Installation

All lining materials will be installed in strict accordance with

manufacturer's specifications. The pond subgrade will be carefully

10

prepared to remove organic materials and protrusions and to provide a

smooth and stable base for the lining system. The membrane liners will

be anchored to the pond side slopes as shown in the accompanying

drawings. More detail concerning the installation and testing of the

synthetic membrane liners is presented in Appendix D.

2.4 Leak Detection

2.4.1 Optional Systems

The leak detection system to be installed depends on and is an

integral part of the liner option selected. The pond bottom leak

detection media for Option A will consist of coarse sand, while geonet

will be used in Option B. Both design options will use coarse sand for

the backfilling of leak detection pipe trenches. HDPE geonet will be

used to convey leakage to the leak detection piping from the pond side

slopes under both optional plans. The details of the leak detection

systems for single liner Option A and double Option B are shown on Maps

4a and 4b, respectively. Details relating to material and construction

specifications for the leak detection system are presented in Appendix

D.

2.4.2 Single Liner Option A

Under single liner Option A, coarse sand will be placed under the

primary geomembrane on the pond bottom. The final sand specifications

will be based on the availability of materials. A typical specification

for coarse sand is provided below. The installed sand blanket will have

a similar gradation and a permeability of at least 100 times the

permeability of the underlying compacted soils.

11

Texture: Coarse Sand

Gradation: Sieve Size Percent Passing (Wt)

3/8 inch 100No. 4 95 -100No. 8 80 -100No. 16 60 -90No. 30 25 -65No. 50 10 -30No. 100 2 -10No. 200 0- 5

If a leak should occur under the Option A plan, the sand would

convey the liquid to one of fourteen equally-spaced horizontal leak

detection laterals consisting of 4-inch perforated SDR 35 PVC pipe. The

leak detection piping will be placed in trenches at a 0.5 percent grade

from the center of the pond toward both ends. Each perforated pipe will

be wrapped in filter fabric to prevent clogging and will be placed a

minimum of 6 inches below the bottom liner. Flow which enters the pipe

will be conveyed to leak detection taps located at the ends of the

laterals. A 6-inch PVC ELL will be installed at the base of each tap to

collect liquid from the laterals.

An estimate of the response time required for liquid from a

potential leak to reach the detection tap from the most hydraulically

remote pond location was made assuming the pond to be at operational

capacity. A leak in the liner high on the inside slope on one end of

the pond would have to travel a maximum distance of 20 feet to reach the

sand at the toe of the embankment. The leak would then have to travel a

maximum distance of 41.7 feet to reach a leak detection tap. In the

middle of the pond, a leak would have to travel a maximum of 47.1 feet

through the sand and then through the 4-inch perforated PVC pipe a

maximum of 415 feet to reach a leak detection tap.

12

The travel time through the geonet on the side slope is minimal due

to its high transmissivity and permeabilities in the range of 200 to 100

cm/sec. For a flow distance of 20 feet and a hydraulic gradient of 0.45

ft/ft (2H:IV), the travel time would be less than one minute. Travel

time through the coarse sand can be expected to be greater due to its

lower permeability. It can be assumed that the effective porosity and

porosity are nearly equal for coarse sands and gravels (Rahn, 1986).

Another assumption can be made that the actual flow velocity is more

closely represented by the true interstitial velocity than by the Darcy

velocity, a fact supported by the relatively short response times noted

during actual tests of in-situ leak detection systems. For a coarse

sand with a porosity of 25 percent and a hydraulic conductivity (k) of

2.0 x 10-2 (Bouwer, 1978), the Darcy velocity (Vd) can be calculated as

follows:

Vd = k x i

where: i = 10 ft/41.7 ft = 0.24

Vd = (2.0 x 10- 2 cm/s) x 0.24

Vd = 4.8 x 10-3 cm/s

The interstitial velocity (Vi) can be calculated from the Darcy velocity

by dividing by the porosity (n):

Vi = Vd/n

V 4.8 x 10 cm/s0.25

Vi = 1.9 x 10- 2 cm/s

13

The travel time through the coarse sand can then be estimated as

follows:

- 41.7 ft x 30.48 cm/ft

1.9 X 10-2 cm/s

Tt = 18.6 hrs

Since the travel time along the side slope is estimated at less than one

minute and the travel time through the pipe is also negligible (from 5

to 10 minutes for a flow rate of 6 to 10 gpm), the travel time through

the sand is the limiting factor. The leak detection system will be

monitored at least once every 24 hours and, therefore, a response time

of less than 20 hours should prove adequate for the timely

identification of any potential leakage. The efficiency and actual

response time of the leak detection system will be determined during

field testing of the system during construction. The details of the

installation and testing of the leak detection system are provided in

Appendix D, Construction Specifications.

2.4.3 Double Liner Option B

The leak detection system for Option B (double liner option) is

designed with fewer perforated laterals and taps due to the much higher

hydraulic efficiency of the geonet which will be used in place of coarse

sand on the pond bottom. The leak detection design for the double lined

system is shown on Map 4b. The piping layout consists of three 4-inch

perforated PVC laterals equally spaced along the bottom of the pond.

The perforated leak detection piping will be wrapped in filter fabric

and placed in sand-filled trenches sloping toward the pond ends in a

14

manner similar to the design of Option A. The maximum distance between

the laterals will be 125 feet for Ponds 3 & 4.

A typical 0.508-cm thick geonet has a transmissivity of

approximately 1.5 x 10-3 sq m/sec at a static pressure of 1 ksf (NSC,

1987). The permeability (k) can be calculated from the transmis~sivity

(T) by dividing by the saturated thickness (b), where b is the thickness

of the geonet.

k = T/b

k (1.5 x 10-3 m2/s)(1 x 10-4 cm2m2)0.508 cm

k = 29.5 cm/s

The flow velocity can then be estimated from Darcy's equation.

V= k i

where: i = 10 ft/125 ft = 0.08

V = 29.5 cm/s x 0.08

V = 2.36 cm/s

Using the maximum distance between laterals (125 ft), the response time

can be estimated as follows:

= 125 ft x 30.48 cm/ft2.36 cm/s

Tt = 26.9 minutes

Under this design option, the total travel time from the most remote

area of the pond should be less than one hour including the time

required for flow to travel through the maximum length of perforated

pipe as calculated previously. The actual efficiency and response time

15

for the leak detection system will be determined by field tests

conducted during construction. Details of the installation and testing

of the leak detection system are included in the Construction

Specifications (Appendix D).

3.0 GEOTECHNICAL INVESTIGATION

3.1 Field Investigation

A subsurface investigation of the commercial pond site was

conducted by staff of Western Water Consultants in late April 1988.

Geotechnical work conducted at the site included the completion of 6

test borings. One boring was located in the approximate center of each

of the five evaporation pond locations and another was drilled at the

location of the proposed facilities building. The boreholes were logged

and field samples were composited from cuttings at specified intervals.

The logged description of the soils encountered during drilling

identifies the deeper (greater than 3 feet) material in all six

boreholes as silty sand. Due to the stratigraphic and textural

similarity of all six boreholes, one split spoon sample. was sufficient

to provide an estimate of in-place soil conditions. The logs of the

boreholes are included in Appendix B.

3.2 Laboratory Analyses

A composite sample of the soil material underlying Pond 2 was sent

to Braun Engineering Testing, Billings, Montana, for analysis. Analyses

performed by the laboratory included direct shear, compaction, gradation

and permeability tests. The results of the laboratory tests are

summarized in Table 3, and copies of the results of the lab analyses are

16

Table 3. Soil Engineering Test Results for the Pond 21. 2.

Composite Sample

Unified Soil Classification: SM (Silty Sand)

Maximum Dry Density: 105 pcf

Optimum Moisture Content: 16. 5 X-6

Hydraulic Conductivity: 3. 1 x 10 cm/s(95Z Std. Proctor)

RECOHMENDED STREBGTH FARAMETERS

0

Friction Angle: 40

Cohesion: 0

Note: i.

2.

Soil analyses were conducted by Braun EngineeringTesting, Billings, Montana.Copies of the lab test results are included inAppendix C.

17

included in Appendix C. The gradation analysis confirms the field

description of a non-plastic soil classified as a silty sand (SM) under

the Unified Soil Classification Method.

A compaction test of the composite sample was conducted according

to ASTM D698 to determine the optimum moisture content and corresponding

maximum dry density. The results of the compaction test fix the maximum

dry density at 105 pcf and the optimum moisture content at 16.5 percent.

A direct shear test was performed to provide an indication of the

strength properties of the foundation and borrow materials underlying

the pond area. As shown in Table 3, the suggested strength design

parameters include a friction angle of 40 degrees and a cohesion of 0.

The results of falling head permeability tests performed on a split

spoon sample from the 10-11 foot interval underlying Pond 5 show a

permeability of 1.3 x 10-5 cm/s. Permeability tests were also performed

on the composite Pond 2 material after achieving 95 percent Standard

Proctor compaction. The results of three tests show an average

permeability after compaction of 3.1 x 10-6 cm/s.

3.3 Slope Stability Analysis

A computer evaluation of embankment slope stability for the solar

evaporation pond design was conducted using the recommended soil

strength parameters discussed above and shown in Table 3. The

basic-language computer program REAME (Huang, 1983) was used to perform

the evaluation. The program is based on the simplified Bishop method

and employs an iterative search procedure to find the critical failure

surface.

18

The stability evaluation was conducted for the maximum embankment

cross section for the pond system in the northwest corner of Pond 3 (see

Map 2). Figures 1 and 2 show the evaluated cross sections of the inside

and outside slopes and illustrate the results of the stability analyses.

Static and dynamic factors of safety were determined for each cross

section. A seismic coefficient of 0.05 was used in the dynamic

stability analyses. The effects of the synthetic membrane liner and the

operational water surface were neglected in the analysis of slope

stability for the inside embankment slope. This results in a

conservative approach since the tensile strength of the liner and static

pressure of the water would tend to buttress the inside slope of the

pond thus increasing the safety factor (Koerner, 1986).

The lowest computed factor of safety for the conditions studied is

1.7, the dynamic safety factor for the inside pond slope. A static

safety factor of 1.9 is estimated for the inside slope and static and

dynamic safety factors of 2.2 and 1.9, respectively, were calculated for

the outside slope. The results of the stability analyses shown in

Figures 1 and 2 demonstrate that the design slopes are appropriate for

the construction materials and methods proposed for these structures.

Earthwork specifications for the evaporation pond construction are

presented in Appendix D.

4.0 CONSTRUCTION SPECIFICATIONS AND QUALITY ASSURANCE

4.1 Specifications

Detailed specifications for the materials and work associated with

the construction of the solar evaporation ponds are provided in Appendix

D, Construction Specifications. The appendix presents the general

19

FIGURE

3906-

3896

E 3886

I. SOLAR EVAPORATION POND SLOPE STABILITY ANALYSIS(2H:IV Inside Slopes)

CENTER PT (38.00. 3902)I

1I

/

All 4

K!I

- -

-W 3876-0ci

3866--

CREST ELEV. 3881 k,•

I, OPERATING WSL 3876

CO MPUTMIDUR

SURFACE"OE ELEV. 3866

3856I -1 0 I I I I I I I I I I I I I i I I I I I . I I I I I I I I I I I I I I I I I I I I I I I I I-00 10 20 30 40 50 60

Horizontal Distance (ft)

FIGURE 2. SOLAR EVAPORATION POND SLOPE STABILITY(2.5H:lV Outside Slopes)

ANALYSIS

CEUM PT (81.35. 3968)3970

3950

3930 -

E

**'3910

0

> 3890-

3870-

3850

3881

ELEV. 3858

-10 10Horizontal Distance (ft)

construction and technical specifications required to be met during the

construction of the solar evaporation ponds at Crow Butte. The

information presented herein is provided for permitting purposes and to

aid reviewers in determining the adequacy of proposed construction and

quality assurance methods. The specifications summarized in this

section will form the basis of a construction document to be developed

after regulatory approval. This approach will save the time and effort

involved in creating and revising a formal construction document during

the permitting process.

4.2 Engineer Supervision

During major phases of construction, an engineer familiar with the

.plans and specifications will be on site and shall sup ervise the work.

It will be the responsibility of the engineer to insure the quality of

the work. Installation contractors will be utilized for the

installation of lining materials and will be responsible for that

portion of the work. All lining materials will be installed in strict

accordance with the manufacturer's recommendations. Methods to be used

to insure quality materials and workmanship are specified in Appendix D.

4.3 Quality Assurance

In general, quality assurance will be insured by the use of field

testing which will be conducted as specified in the Construction

Specifications to maintain quality control. In addition, documentation

will be required from suppliers and installers to validate the quality

of materials and the qualifications of contractors and warranties of

22

materials and workmanship will be required for the major components of

work such as the installed liners.

5.0 EVAPORATION POND OPERATION

5.1 Wastewater Characteristics and Piping Details

The estimated operational average daily flow rates expected to be

discharged to the evaporation pond system include the following:

Average Daily Flow (years 1-3) 18,300 gpd

Average Daily Flow (years 4-10) 108,200 gpd

The characteristics and estimated waste strength for the wastewater

influent to the ponds are as follows:

Wastewater EstimatedParameter Concentration (mg/l)

U30 8 0.2 - 100

Cl- 200 - 75,000

SO4 500 - 40,000

CO3 (total) 10 - 5,000

Na 50 - 75,000

Ca 10 - 1,000

NOTE: A limited amount of reverse osmosis (R.O.) permeate mayoccasionally be sent to the ponds which would have parameterconcentrations lower than those shown above.

Piping between the evaporation ponds and the plant building will

consist of buried pipelines. A schematic of the typical piping detail

is illustrated by Figure 3. The pond system will be operated so that

individual pond contents can be transferred to any other pond by the use

of portable submersible pumps.

23

FIGURE 3. TYPICAL SOLAR EVAPORATION POND-PLANT BUILDING PIPING DETAIL

Plant Building

Ground Level

oBurid pipeline topond cell, typical,

Legend

FE.....Flow MeterFT ..... Flow Totalizer

S.....Sample Port

5.2 Operational Monitoring

-The evaporation ponds will be, inspected quarterly for signs of

settlement and erosion. Daily inspections will be performed to

determine if any damage has occurred to the liner, external pipes, or

earthwork. Quarterly reports will be prepared and kept at the project

site for reference and review.

The leak detection system which is described in detail in Section

2.4 will be monitored daily for liquid in the sumps. If a liquid level

of 3 inches or more is detected, a sample will be collected for analyses

and the location and time will be noted. Once a, leak. is determined to

exist, the pond will be dewatered by pumping the contents into the

reserve capacity of one or two other ponds. During dewatering, leak

detection taps which collect leakage will be continuously pumped to an

adjacent pond.

After the pond is evacuated, the leak will be located by inspection

and testing and the liner will be repaired and retested according to the

manufacturer's specifications. No wastewater will be reintroduced into

the pond until the liner has been thoroughly and satisfactorily tested.

5.3 Maintenance

The evaporation pond embankments and slopes will be inspected

regularly as discussed above and corrective measures undertaken if

problems are noted. The outslopes and ditches will be stabilized

against erosion by the establishment of vegetation which will consist of

the following seed mix:

25

Proposed Mix Lbs. PLS/acre % Mix Lbs. PLS/acre

Smooth Brome Manchar 13 35 4.5Russian Wildrye Vinall 10 30 3.0Crested Wheatgrass Nordan 10 35 3.5

PLS: Pure Live Seed 11.0

The fence will be maintained throughout the operational life of the

structures.

All piping and other appurtenances will be inspected and maintained

to insure that conditions detrimental to the environmentally safe

operation of the pond system do not develop. A log of inspections and

required maintenance activities will be kept at the project site and

will be available for reference and review.

5.4 Fencing

Access to the pond area will be controlled by fencing. The

immediate pond area will be protected by a game-proof fence consisting

of a 7-foot high 6" x 6" woven wire fence with a single-strand, barbed

top wire. The fence will be located as shown on Map 1.

6.0 REFERENCES

Bouwer, Herman, 1978, Groundwater Hydrology, McGraw-Hill Book Company.

Huang, Yang H., 1983, Stability Analysis of Earth Slopes, Van NostrandReinhold Co., New York, NY.

Koerner, R. M., 1986, Designing With Geosynthetics, Prentice-Hall,Englewood Cliffs, NJ.

National Seal Company, 1987, Technical Manual.

Nebraska Department of Environmental Control, April 1975, Title 123 -Rules and Regulations for Design, Operation and Maintenance ofWastewater Treatment Works.

26

Rahn, P. H., 1986, Engineering Geology - An Environmental Approach,Elsevier Science Publishing Co., Inc., New York, NY.

U.S. Army Corps of Engineers, 1986, The Hydrologic Engineering Center,HEC-2 Water Surface Profiles Generalized Computer Program, UpdatedPC Version.

U.S. Department of Commerce, March 1984, National Oceanic andAtmospheric Administration, Hydrometeorological Report No. 55:Probable Maximum Precipitation Estimates - United States Betweenthe Continental Divide and the 103rd Meridian.

U.S. Department of Interior, Bureau of Reclamation, Design of SmallDams, 2nd Edition 1973, Revised Reprint, 1977.

U.S. Nuclear Regulatory Commission, Office of Standards Development,December 1977, Regulatory Guide 3.11: Design, Construction, andInspection of Embankment Systems for Uranium Mills, Revision 2.

U.S. Nuclear Regulatory Commission, Uranium Recovery Licensing Branch,Staff Technical Position Paper #WM-8101, Design, Installation, andOperation of Natural and Synthetic Liners at Uranium RecoveryFacilities.

Western Water Consultants, Inc., 1986, TRIHYDRO - a computer program forthe calculation of rainfall/runoff using the SCS triangularhydrograph procedure.

27

APPENDIX A

10 Sq. Mi. 6-Hour PMP Flood Studies

28

FEN Runoff Control Ditch Capacity for 6-Hr PMP = 23"

EBA IN in FHAE RF I ET I- X E

DRAINAGE AREA (SQ. MI.) ........ ............ = 0.008STREAM LENGTH (MI.) .................... = 0.095ELEVATION DIFFERENCE (FT.) . . ......... ........ = 24.000RUNOFF CURVE NUMBER, CN ........ ........... = 69.000MINIMUM INFILTRATION LOSS (IN./HR.) ......... = 0.140

F='F;E=Cý I F=" I TATci-I I CON4F= : F;:R E SF'E-= - I F:: I FnE ! -ST3OR M

ADJUSTED PRECIPITATION FOR SELECTED STORM . . . . = 23.00

LN I -T- YD:CRAF' F'A- =AMETEF

UNADJUSTED TIME OF CONCENTRATION (HR.) ... ..... = 0.05ADJUSTED TIME OF CONCENTRATION (HR.) ............... = 0.05DURATION OF EXCESS RAINFALL, D (HR.) .... ...... = 0.01.TIME TO PEAK (HR.) . . . . . . . . . . . . . . 0. 7BASE TIME (HR.) ............. ................. . .0.09QPEAK:: (PEAK FLOW IN CFS FOR UNIT HYDROGRAPH) . . = 115.2

RE SLJLLTANT H°DROGGRAF'- AL1JES

PEAK DISCHARGE (CFS) ............ .............. = 69.47RUNOFF VOLUME (ACRE-FEET) ....... ............ = 12.36TIME TO PEAK DISCHARGE (HR). . ..... . . . ... = 10.00

USED 6-HR GENERAL STORM, ZONE C, EXTENDED FOR 18 HOURS

FEN Runoff Control Ditch Capacity +or 6-Hr PMP = 23"

BASI NJ CAFATEF: I S;T I CS

DRAINAGE AREA (SQ. MI.) .............. ..... = 0.024STREAM LENGTH (MI.) ............ ............. = 0. 189ELEVATION DIFFERENCE (FT.) ........ ........... = 66.000RUNOFF CURVE NUMBER., CN. . . ..... ........ = 69.000MINIMUM INFILTRATION LOSS (IN./HR.) .......... = 0.140}

F' R E=Cý I F°" I TAT In ON E 3P -C FOR E SF' EC- (-I F= I E=_ D E3STCOF::RM

ADJUSTED PRECIPITATION FOR SELECTED STORM . . . . = 23.]00

UN I T H DROGRAF'H F'R •NT

UNADJUSTED TIME OF CONCENTRATION (HR.) ..... = 0.08ADJUSTED TIME OF CONCENTRATION (HR.) .. ...... = 0).08DURATION OF EXCESS RAINFALL, D (HR.) .. ...... = 0.01

TIME TO PEAK (HR.) .................. .............. 05BASE TIME (HR.) ...................... = 0.13QPEAK (PEAK-: FLOW IN CFS FOR UNIT HYDROGRAPH) = 230. 6

1ES=;FE L N T H D GFRAF='" VALUJES

PEAK DISCHARGE (CFS) ............ .............. = 208.31RUNOFF VOLUME (ACRE-FEET) ......................... = .7.7

TIME TO PEA:K DISCHARGE (HR) ......... ........... = 10.01


FERRET EXPLORATION PMF, SUBAREA A -- 6-HR 10 SQ. MI. PMP = 23 INCHES

EBA4 I N CH " R=CTE R I I CS

DRAINAGE AREA (SQ. MI. ). ... ............... . = .0.06- 0STREAM LENGTH (Mi.) ... ................... = .400ELEVATION DIFFERENCE (FT.) ........ ........... = 80.000RUNOFF CURVE NUMBER, CN *...............- = 69. (:)00MINIMUM INFILTRATION LOSS (IN./HR.) ... ....... = 0.140

ADJUSTED PRECIPITATION FOR SELECTED STORM .... = . .U

UNADJUSTED TIME OF CONCENTRATION (HR.) . .... = 0.17ADJUSTED TIME OF CONCENTRATION (HR.) .. ...... = 0. 17DURATION OF EXCESS RAINFALL, D (HR.) ...... = 0.02TIME TO PEAK (HR.) . .......... = . .. iBASE TIME (HR.) ................. ................. = C.QPEAK (PEAK FLOW IN CFS FOR UNIT HYDROGRAPH) = ct2. 1

PEAK DISCHARGE (CFS) ............ .............. = 517.78RUNOFF VOLUME (ACRE-FEET) ....... .......... . . = 92. 6ETIME TO PEAK DISCHARGE (HR) ....... ........... = 10.02


APPENDIX B

Geotechnical Test Hole Logs

29

BOREHOLE 1

PAGE -I- OF ILOG OF EOREHOLELOC. ORCOORDS T.31 N, R. 51 W DRILLER CHUCK CORLEY START FINISH

SEC 19 WESTERN WATER CONSULTANTS

GROUND ELEY -3900" ABOVE MSL DATE 3/29/88 3/29/88

TOTAL DEPTH 17.0' RIG GIDDINGS SOIL SAMPLER TIME 2:30 3:30

BOREHOLE DIAM. 3" BIT(S) SOLID STEM AUGER GEOPHYS LOG

------__ __ __ _ FLUID NONE

DEPTH MATERIAL DESCRIPTION AND COMMENTSi-

0

a_t-

o

z

I(JU

0-j

m0J

-J

0-2.0'

2-6.0'

6-17.0'

SANDY SOIL

SILTY SAND

SILTY SAND

DARK BROWN, MOIST, SANDY SOIL. ABUNDANT ORGANIC DEBRIS.

BROWN, SLIGHTLY MOIST, SILTY SAND. SAND IS VERY FINE TO FINE-GRAINED, UNCONSOL ID ATED, VERY WELL SORTED, SUB ANGUL ARGRAINS, ARKOSIC. DOES NOT REACT TO HYDROCHLORIC ACID.SAMPLE IS SEMI-COHESIVE UNDER HAND-APPLIED PRESSURE.

BROWN, SILTY SAND, SAME AS ABOVE. SAMPLE IS CALCAREOUS,OCCASIONAL (3%) FINE GRAVELS. OCCASIONAL ORGANIC DEBRIS(ROOTS AND PLANT REMNANTS), SLIGHTLY MOIST TO MOIST.SAMPLE IS SEMI-COHESIVE UNDER HAND-APPLIED PRESSURE.(SAMPLES FROM THIS BORING APPEAR MORE MOIST THAN PREVIOUSHOLES)

14.0'- INCREASING PERCENTAGE OF HORNBLENDE/BIOTITE WITHDEPTH.

GROUND COVER: YUCCA CLUSTERS AND PRAIRIE GRASS

a--

CCZ

C-) LL

u

0D -

(JjL

-30

c, aterY on~utsitnts

BOREHOLE 2

P AGE 1 1FLLOG OF BOREHOLELOC.ORCOORDS T. 31 N, R. 51 W, DRILLER CHUCK CORLEY START FINISH

SEC 19 WESTERN WATER CONSULTANTS

GROUND ELEY -3902" ABOVE MSL DATE 3/29/88 3/29/88

TOTAL DEPTH 13.0' RIG GIDDINGS SOIL SAMPLER TIME 11 :05 12:00


FLUID NONE

DEPTH MATERIAL DESCRIPTION AND COMMENTSzC)

CL

L_0c.

z

u

C-,

C

F-

--J

0~

ILa

0-2.8' SANDY SOIL

m,J

00_j

2.8-5.0'

5-13.0'

SILTY SAND

SILTY SAND

DARK BROWN, MOIST, SANDY, ORGANIC SOIL. VERY RICH 'EARTHY'ODOR. VERY FINE TO FINE-GRAINED SAND, SILTY, ROOT AND PLANTDEBRIS ABUNDANT.

BROWN, MOIST, SILTY SAND. SAND IS VERY FINE TO FINE-GRAINED,ARKOSIC, VERY WELL SORTED, SUBANGULAR. SILT CONTENT MAKESSAMPLE SEMI-COHESIVE UNDER HAND-APPLIED PRESSURE. DOES NOTREACT TO HYDROCHLORIC ACID. -355 FINE GRAINED GRAVEL, MINOR% ORGANIC DEBRIS (BORING IS LOCATED IN A STAND OF YUCCA),S AMPLE IS PREDOMINANTLY SAND.

SAME AS ABOVE EXCEPT SAMPLE IS LIGHT BROWN (TAN) IN COLOR,CALCAREOUS AND SLIGHTLY MOIST. SAMPLE IS SEMI-COHESIVEUNDER HAND-APPLIED PRESSURE. OCCASIONAL ROOTS PRESENT TO8.0'.

GROUND COVER: YUCCA CLUSTERS AND PRAIRE GRASS

CC

cc.

C0 neoter nW' a ter

TConsu(ltante

BOREHOLE 3

PAGELOF ILOG OF BOREHOLE

LOC.OR COORDS T. 31 N, R. 51 W, DRILLER CHUCK CORLEY START FINISHSEC 19 WESTERN WATER CONSULTANTS

GROUND ELEY 3871 ABOVE MSL DATE 3/29/82 3/29/88TOTAL DEPTH 17.5' RIG GIDDINGS SOIL SAMPLER TIME 3:40 4:30

BOREHOLE DIAM. 3' BIT(S) SOLID STEM AUGER GEOPHYS LOG

FLUID NONE YESXN0DEPTH MATERIAL DESCRIPTION AND COMMENTS

z

C)

0~

z

-Cc

0-dE

-J

0-3.0'

3-I 7.5'

SANDY SOIL

SILTY SAND

In

0

-J

DARK BROWN, MOIST, ORGANIC, SANDY SOIL. ABUNDANT ROOTSAND PLANT DEBRIS. DOES NOT REACT TO HYDROCHLORIC ACID.

BROWN, SILTY SAND. SAMPLE IS PREDOMINANTLY SAND (~90%SAND/ib% SILT), SAND IS VERY FINE TO FINE-GRAINED, WELLSORTED, SUB ANGUL AR, UNCONSOL ID ATED, SL IGHTLY MO IST,SMALL % ORGANIC DEBRIS, ARKOSIC.

7.0'-SAMPLE EFFERVECES WITH THE ADDITION OF HYDROCHLORICACID (C ALC AREOUS).

1 7.0-576 FINE TO MEDIUM GRAVELS.

GROUND COVER: PRAIRIE GRASS

C-)

CL.

_7D

ca

a.I-I

W;Cl

"3C-)

Ci

.ea

aaLL

L.L

-1e-tprn.afer

BOREHOLE 4

PAGE__L OFLLOG OF BOREHOLE

LOC.ORCOORDS T. 31 N, R. 51 W,SEC 19

GROUND ELEY -3886' ABOVE MSLTOTAL DEPTH 12.0'

BOREHOLE DIAM. 3"

DRILLER CHUCKCORLEY START FINISHWESTERN WATER CONSULTANTS

DATE 3/29/88 3/29/88

RIG GIDDINGS SOIL SAMPLER TIME 1 :20 2:20

BIT(S) SOLID STEM AUGER GEOPHYS LOG

FLUID NONE -YES XŽ.NO-I

v0

za-

z0 :

('u 0

_o,

-a

p.-

o'lCL

I

5 _5'

SANDY SOIL

SILTY SAND

SILTY SAND

SILTY SAND

SILTY SAND

SILTY SAND

DESCRIPTION AND COMMENTS

DARK BROWN, MOIST, SANDY SOIL. ABUNDANT ORGANIC DEBRIS.

LIGHT BROWN (TAN), SLIGHTLY MOIST, VERY SILTY SAND. SAND ISVERY FINE TO FINE-GRAINED, ARKOSIC, VERY WELL SORTED, SUB-ANGULAR. SILT CONTENT MAKES SAMPLE SEMI-COHESIVE UNDERHAND-APPLIED PRESSURE. DOES NOT REACT TO HYDROCHLORýICACID. SAMPLE APPEARS MORE FINE-GRAINED/SILTY THANBOREHOLES a ,I2, U3 AND -5.

3.0'-REACTS TO HYDROCHLORIC ACID (CALCAREOUS).

SAME TAN SAND. SILT CONTENT DECREASES SLIGHTLY, MOIST.SEMI-COHESiYE UNDER HAND-APPLIED PRESSURE. VERY FiNE-GR A INED, WELL SORTED, SUB ANGULAR, UNCONSOLIDATED,CALCAREOUS, ARKOSIC. SLIGHTLY MOIST FROM 5.0' TO 6.'

SAME TAN SAND AS ABOVE, EXCEPT SAMPLE IS SLIGHTLY MOISTTO MOIST WITH A NOTICEABLE INCREASE IN SILT CONTENT.BOREHOLES a I, 02, 03 AND *5 WERE COMPRISED OF -85-903ZSAND AND 10-157 SILT. BOREHOLE n4 IS 70-80-6 SAND AND20-30"7, SILT. SILT 'SMEARS' ARE NOTICEABLE ON THE AUGER.DRILLING IS INCREASINGLY MORE DIFFICULT WITH DEPTH. SAMPLESTICKS TO AUGER.

SAME SILTY SAND AS ABOVE. SILT CONTENT DECREASES SLIGHTLY.

SAME AS ABOVE. SILT CONTENT INCREASES SLIGHTLY.

GROUND COVER FR AIRE GRACS

ww. et er fl"W

t e r

Sor~sultsnta

BOREHOLE 5

PAGE I OF 1LOG OF BOREHOLE

LOC.ORCOORDS T.31 NR.51 W,SEC 19

GROUND ELEY -3893' ABOVE MSLTOTAL DEPTH 10.0'BOREHOLE DIAM. 3"

DRILLER CHUCK CORLEYWESTERN WATER CONSULTANTS START FINISH

DATE 3/29/88 3/29/88

RIG GIDDINGS SOIL SAMPLER TIME 9:05 9:55

BIT(S) SOLID STEM AUGER GEOPHYS LOG

FLUID NONE _YES.-ŽLNOt

Lo

z0

0~Ix.

z

0

DESCRIPTION AND COMMENTS

-J I-J

m0LaCDCD0-I

SANDY SOIL

SILTY SAND

SILTY SAND

SILTY SAND7-

DARK BROWN, MOIST, SANDY, ORGANIC SOIL. ABUNDANT PLANTAND ROOT DEBRIS.. DOES NOT REACT WITH HYDROCHLORIC ACID.

BROWN, SLIGHTLY MOIST, VERY FINE-GRAINED TO FINE-GRAINED,SILTY SAND. DOES NOT REACT TO HYDROCHLORIC ACID (NON-C ALC AREOUS), WELL SORTED, UNCONSOLIDATED, SUB- ANGUL ARGRAINS, ARKOSIC. SILT CONTENT IS HIGH ENOUGH THAT SAMPLEIS SEMI-COHESIVE UNDER HAND-APPLIED PRESSURE. SAMPLE ISPREDOMINANTLY SAND.

SAME AS ABOVE. SILT CONTENT INCREASES. NO PHYSICAL CHANGEEXCEPT SAMPLE IS COHESIVE UNDER HAND-APPLIED PRESSURE.

SAME AS ABOVE. CALCAREOUS (REACTS WITH HYDROCHLORIC ACID),SLIGHT COLOR CHANGE TO LIGHT BROWN (TAN).

SPLIT SPOON SAMPLE OBTAINED FROM 10.0-1 1 .0' INTERVAL FORLAB ANALYSIS.BLOW COUNT: 8-8-9 FOR 18".

GROUND COVER. PRAIRE GRASS

QI

Ow-lof•

0dI•

ola

0_

aterCo.nultants

BOREHOLE PLANT SITE

PAGE--L_ FLLOG OF B3OREHOLE

LOC.ORCOORDS T. 31 N, R. 51 W, DRILLER CHUCKCORLEY START FINISH

SEC 19, NW SE WESTERN WATER CONSULTANTS

GROUND ELEY. DATE 3/29/88 3/29/88

TOTAL DEPTH 15.o- RIG GIDDINGS SOIL SAMPLER TIME 4:50 5:35


FLUID NONE

DEPTH MATERIAL DESCRIPTION AND COMMENTSL.JI'-C',I'-z-Jci-L&J

L.~.

0-2.5' SILTY SAND

z

0C-

m

.J

0(D0-i

5-8.0'

8-10.0'

10-15.0'

SILTY SAND

SILTY SAND

SILTY SAND

SILTY SAND

BROWN, VERY SLIGHTLY DAMP, SILTY SAND. SAND. IS VERY FINE-GRAINED, WELL SORTED, SUBANGULAR, UNCONSOLIDATED,SAMPLE COMPRISES -90% SAND AND IO¶Z SILT. -55 ORGANICDEBRIS (ROOTS AND PLANT FRAGMENTS), NON-CALCAREOUS (DOESNOT REACT TO HYDROCHLORIC ACID), ARKOSIC.

SAME SILTY SAND AS ABOVE, EXCEPT SAND IS DRY AND CAL-CAREOUS.

SAME SILTY SAND AS ABOVE, SLIGHTLY DAMP. % HORNBLENDE/BIOTITE INCREASES SLIGHTLY. SAMPLE IS COHESIVE UNDER HAND-APPLIED PRESSURE.

SAME AS ABOVE WITH THE ADDITION OF CALCAREOUS BLEBS(COMPRISE -3% OF SAMPLE).

BROWN, SILTY SAND, VERY SLIGHTLY DAMP TO DRY, VERY FINE-GRAINED, WELL SORTED, SUBANGULAR, UNCONSOLIDATED, 90•SAND AND 1OZ SILT, CALCAREOUS, ARKOSIC. SAMPLE IS SEMI-COHESIVE UNDER HAND-APPLIED PRESSURE, OCCASIONAL (05s)CALCAREOUS BLESS.

3 COMPOSITE SAMPLES OBTAINED:0-5.0'5-10.0'10-15.0'

GROUND COVER: PRAIRIE GRASS

0- It

Q~Ck

-a

D-

QA.

CD

L-

h i

" eBtern, aterwConrwultanta

APPENDIX C

Soil Lab Test Results, Braun Engineering

30

ILR TETB @IF TBrAM l@H0]=TViRz L

Frontage Rd., P.O. Box 30697, Billings. MT 59107-0697 - 406 / 652-3930x 6190, Bozeman, MT 59771-6190 - 406 / 587-9410

DRAUN'ENGINEERING TESTING

OF MONTANA, INC.

Quality Services Since 1957

Consulting Soils andMaterials Engineers

J.S- BRAUN. P.E. PresidentP.H. ANDERSON, Vice PresidentC.G, KRUSE, PE., Vice PresidentB.M. THORSON. P.E. Vice Pres./Area Engr.

TO Western Water Consultants, Inc.

P.O. Box 3042

Sheridan, WY 82801

DATE 4/13/88 /JOB"°O B88-029

ATTENTION Nick Tiffany

RE:LAB TESTINGSolar Pond SamplesCrow Butte Project

Urawtord, NAb

GENTLEMEN:

WE ARE SENDING YOU

W Test Reports

El Copy of letter

LI

El

Attached LI Under separate cover via_

Prints LI Plans [] Samples

the following items:

L0 Specifications

COPIES DATE NO. DESCRIPTION

1 Direct Shear

1 Compaction Test

1 _Gradation Test

THESE ARE TRANSMITTED as checked below:

EJ For approval LI For your use [3 As requested 0I For review and comment

LI

LI FOR BIDS DUE .19_

REMARKS: Permeability tests are in progress.

Bruce M. Thorson, P.E.Vice Presiden Area Engineer

COPY TOSIGNED:

-Environmental Testing & Consulting Services Affiliate -- Braun Lnvironmental Laboratories, Inc.

Affiliated Offices: Minnesota - Minneapolis - Hibbing - St. Cloud - Rochester - St. PaulNorth Dakota - Williston - Bismarck

Illinois - Chicago

GRADATION TESTHYDROMETER ANALYSIS

TIME READINGS

15 min 60 min 19 min 4 min25

45m1001

hr I~i~ W;. A IU.S. STANDARD SERIES

#50i #AD 0 VI

SIEVE ANALYSIS

I 4

OR NA I/910 .

CLEAR SQUARE OPENINGS/ 3/4, 1 A" 3"

Unn S " 6"in*1 "' min 20 - i

V.10

/

CL

0z

UU'

4.

90 - - ' 0

80 - - ............L..... _ __ __- .. ... .0

I I.

III I

I I i

SI I

I t I

30 7_I_0

20 -8- --

1I I9

z9-w

I-IwU

w0.

I

I t It I I I IllI I I III I I I I 1 I . I I I I I l I1 I01 - *'' ~ ~ 4 ~ 4 A1S ~ 4 . .~ -. 4. --- '-~- 4 4 , 4 ~'' 4 L. 4-'.- 4 L~.J-~J. 4'.L..4..4 -

.001 .002 .005 .009 .019 .037 .074 .149cIAU9D

.297 .590Al DAD*Ibftg4

1.19 2.081.19 2.38 6 9.52

5:

4.7 19.11 7

38.1 76.2 127 152

1100

1n

cM

FINES I SAND I GRAVELI FNE INE MEDIUM COARSE I INE 7 COARSE COBE

CLASSIFICATION SYMBOL SM AT-Gravel .0 % LiSand __ % PIFines 48.9 % Sh

SAMPLE NO. Composite

TERBERG LIMITS -quid Limit -- %asticity Index NP %

rinkage Limit -- %

HOLE NO. Pond #2

SPECIFIC GRAVITY NOTES B88-029

Minus No. 4 -- SOLAR EVAPORATPlus No. 4 Crow Butte Pro

Bulk Apparent -- Crawford, Nebr

DEPTH 0-13' ft( m)

7ION PONDS

Jectaska

1ALI* COMPACTION TEST PROCEDUREASTM Designation:

.Method:Laboratory Maximum Dry Density:

Laboratory Optimum Moisture Content:

4 'rc

DU

r,

z

I-

=

(9

115-

110-

105-

yo-

90-I f

a

80-0 10 15 '20 25 30 35 40

WATER CONTENT-PER CENT OF DRY WEIGHT600?NG I I (E DEP IL SOIL DESCRIPION SOLAR. PONDS

NO. NO (FEET) PL Pi LLI11A JO D .Pond Corm- 773' NP SILTY SAND,.nonplastic, very fine grained, light reddish COMPACTION TEST#2 posit- brown (SM)

DRAWN BY: LFK JOB NO.B88-029CHECKED BY: BMTDATE: 4/7/88 PLATEP-

4

I-

S.

'4'U

U)

.4

3

1

0

E T!

rt

I

]

!

0.00

2 -0.02

> -0.04

I

.J.J.J.

Z.4-

I-1

-- 4

94

+ -

t~I~

L

-4. -,---7 -

ZI

-- 5---

0~

m,

4

3

2

1

0

iI

0 1 2 3 4 5 6NORMAL STRESS, a, T/SQ FT

I

31RIN W-. I 111THI Ili##ft # -1 4fiIt .... +H4

+++-------------- 4-T. --------- i 9t .. I

M M 'q 11-1i 11- 1 i I I

I I . ' ' I .... s . . 1 . 1 1 1 A . I t 1 .

:tt = m t ... .......

VtatI

Ei1 .-1i:IV,

0 0.1 0.2 0.3 0.4 0.5

HORIZ. DEFORMATION, IN.

SHEAR STRENGTH PARAMETERSMax. Ult.

• = 42 ' 4no _

TAN.'= 0.90 0.84

. 0.35 n ,9 ,,soFT

TESt NO. 0 1 A2

WATER CO•T W. 13.3" 13.3% _ % %

MVO4O e. --R --

-SATURATION S. -- % --

t/cu"T " 100.7 100.5

Density A•RI1CONSOLIDATION e 102.6 102.5

TIME POn 5O "IRCENT -- --CONSOtlIDATION, MIN tse

WATRONTEN w, 19 % % O%

VOID RATIO er ..

SATURATION s _ - %

NORMAL STRESS,T/SQ IT 1.00 1.00

MAXIMUM SHEAmsPR..,s. ?/" 1.25 3.90ACTUAL TIME TO 50 40FAI•URE, •IN

RATE 0 STIAIN, IN./1MN0.002 0_-02[E coNmIoLED STRESS

El CONTROLLED STRAINULTIMATE SHEARSTRESS, T/So FT I rotI 1.10 3.62

YPEOFSPCIMEN Remolded (compacted) f 2.50 N. Depth 1.00 IN.THICK

CLASSIFICATION SILTY SAND, very fine. grained, light reddish brown (SM)

LL -- NP P. -- P2 0 0 =49% I -.

REMARKS Sample was compacted to PROECT B88-029 SOLAR EVAPORATION PONDS

about 96% and consolidated to Crow Butte Project

about 971% prior to testing. AREA Pond #2 Crawford, NebraskaSuggest using 0=40', c=0 fordesign.oE"H DATE APRIL 12, 1988

DIRECT SHEAR TEST REPORT

rontage-Rd., P.O. Box 30697, Billings. MT 59107-0697 - 406 / 652-39306190, Bozeman, MT 59771-6190 - 406 / 587-9410

ENGINEERING TESTINGOF MONTANA, INC.


Consulting Soils andMaterials Engineers

J.S. BRAUN. P.E.. PresidentP.H. ANDERSON. Vice PresidentC.G. KRUSE. P.E.. Vice PresidentS.M. THORSON, P.E. Vice Pres.iArea Engr.

Western Water Consultants, Inc.0

P.O. Box 3042

Sheridan, WY 82801

GENTLEMEN:

DATE 4/25/88 J°SN° B88-029

ATTENTION Nick Tiffany

RE: LABORATORY TESTING

Solar Pond Samples

Crow Butte Project

Crawford. NB

WE ARE SENDING YOU E] Attached 13 Under separate cover via the following items:

o Test Reports

El Copy of letter

0 Prints 0l Plans El Samples El Specifications

El

COPIES DATE NO. DESCRIPTION

1 4/25/88 Permeability Tests (2)

THESE ARE TRANSMITTED as checked below:

El For approval El For your use El As requested El For review and commentEl

El FOR BIDS DUE ,19

REMARKS:

COPY TO

Bruce M. Thorson, P.E.Vice President/Area Engineer

SIGNED:Environmental Testing & Consulting Services Affiliate - Braurn Environmental Laboratories, Inc.

Affiliated Offices: Minnesota - Minneapolis - Hibbing - St. Cloud - Rochester - St. PaulNorth Dakota - Williston - Bismarck

Illinois - Chicago

ENGINEERING TESTINGOF MONTANA, INC.


Frontage Rd., P.O. Box 30697, Billings, MT 59107-0697 - 406 / 652-3930 Affiliated Offices:

Minnesota North DakotaMinneapolis Williston

St. Cloud BismarckRochester

Hibbing Montana

St. Paul Billings

Bozeman

Illinois

Chicago

LABORATORY PERMEABILITY TEST (FALLING HEAD)

Date: April 25, 1988

ReportedTo: Western Water Consultants

Attn: Nick TiffanyP.O. Box 3042Sheridan, WY 82801

B88-029 LABORATORY TESTINGProject: Solar Pond Samples

Copies: Crow Butte Project

SAMPLE DATA:

Sample No. Split spoon Location: Pond 5 Depth: 10-11'Description: SILTY SAND, fine grained, light reddish brown

LL: NT PL: NT PI: - % Passing #200: NT % Passing 0.002 mm: NT.Unified Classification: SM (visual) Textural Classification: Sandy Loam (visual)

Maximum Dry Density (ASTM D -- ): NT pcf Optimum Moisture Content: - %Sampled By: Western Water Consultants Natural Moisture Content: 12.0 %

Final Moisture Content; 41.1%

SPECIMAN DATA.

Molding MC: NA % Dry Density: 77- pcf Relative Compaction: NA %Sample Diameter: 3.71 cm Height: 11.24 cm Cross-Section Area: 10.8 cm'Standpipe Area: 0.317 cm' Confining Pressure: -

TEST RESULTS:

Initial Final Time, Permeability

Run Head, cm. Head, cm. sec. cmrsec ftlmin

4 154.3 6.8 SY W I.jIgx-55 152.9 9.3 86,100 i.IxlO-56 152.9 9.2 86,110 l.1xl0-5

Average 13 x10- 5 2.5*.X1O-5

REMARKS:

Sample was delivered in split spoon sampler. It was fragile, so it was frozen topermit handling. When it thawed, it settled somewhat and increased in diameter in-dicating disturbance.

BRAUN ENGINEERING TESTING

OF MONTANA, INC.

Bruce M. Thorson, P.E.Area Engineer

BRAND1ENGINEERING TESTING

OF MONTANA, INC.


3'"1 •Frontage Rd., P.O. Box 30697, Billings. MT 59107-0697 - 406 / 652-3930 Affiliated Offices:

Minnesota North DakotaMinneapolis Williston

St. Cloud BismarckRochester

Hibbing Montana

St. Paul Billings

Bozeman

Illinois

Chicago

LABORATORY PERMEABILITY TEST (FALLING HEAD)

Date: April 25, 1988

Reported To: Western Water Consultants

Attn: Nick TiffanyP.O. Box 3042Sheridan, WY 82801

Project: B88-029 LABORATORY TESTINGSolar Pond Samples

Copies: Crow Butte Project

SAMPLE DATA:Sample No. Composite Location: Pond #2 Depth:. 0-13'Description: SILTY SAND, nonplastic, very fine grained, light reddish brown

LL - PL: NP Ph: - % Passing #200: 49 % Passing 0.002 mm: 10Unified Classification: SM Textural Classification: Sandy LoamMaximum Dry Density (ASTM D 698 ): 105 pcf Optimum Moisture Content: 16-

Sampled By: Western Water Consultants Natural Moisture Content: -- %

Final Moisture Content 22.7%

SPECIMAN DATA-Molding MC: 17. 6 % Dry Density: 99.8 pcf Relative Compaction: 95 %Sample Diameter. 7. 11 cm Height: 14.22 cm Cross-Section Area: 39.7 cm,

Standpipe Area: 0.317 cm2 Confining Pressure: -

TEST RESULTS:

Initial Final Time, PermeabilityRun Head, cm. Head, cm. sec. cmrsec ftlmln

4 165.4 22.8 55,200 4.1xlO-65 159.8 17.5 86,100 2.9xlO-66 159.2 .21.5 86,100 2.6xi0-6

"Average 3.,x10-6 6.0x10-6

REMARKS:

Remolded sample.

BRAUN ENGINEERING TESTINGOF MONTANA, INC.

Bruce M. Thorson, P.E.Area Engineer

APPENDIX D

Construction Specifications

31

CONSTRUCTION SPECIFICATIONS

This document presents the general construction and technicalspecifications required for the construction of five solar evaporationponds at Ferret Exploration Company's Crow Butte in-situ uraniumproject. These specifications were prepared by Western WaterConsultants, Inc. to accompany plans and a design report dated April 27,1988.

The information presented herein is provided for permittingpurposes and is to aid reviewers in determining the adequacy of proposedconstruction and quality assurance methods. Specifications summarizedin this section will form the basis of a construction contract documentto be developed after regulatory approval of the pond design.

Nebraska P.E. No. E-6477

1

1.0 EARTHWORK SPECIFICATIONS AND TESTING

Earthwork required for the construction of the solar evaporationponds will consist of clearing and grubbing; 'stripping of topsoil;excavation; and placement of compacted fill for the pond bottomsand embankments. During all phases of earthwork the Contractorshall use extreme caution to avoid a conflict with or contact ordamage to overhead utilities, such as power lines, telephone lines,poles or other appurtenances during construction.

Prior to the beginning of construction, and throughout theconstruction period the pond locations will be- inspected by theContractor and Engineer to look for obvious evidence of drillingactivity and unsealed holes which may adversely effect theperformance of the evaporation ponds and their associated leakdetection system.

1.1 Clearing and Grubbing

.Clearing and grubbing will consist of the removal and disposal ofall timber, brush, trash and other organic material within thedesignated work limits. Grubbing shall include the removal anddisposal of roots, stumps and other objectionable debris from thework area.

Trees, logs, stumps, brush and other rubbish shall be piled andburned or otherwise disposed of so as to leave the work area in aclean condition. Permits for the disposal or burning of debrismust be obtained as required and will be the responsibility of theContractor. Clearing and grubbing must be completed to *thesatisfaction of the Engineer prior to the commencement of generalearthwork.

1.2 Stripping

Stripping will consist of the removal of the top 6 inches oftopsoil and waste material within the specified work limits to thedepths specified by the Engineer. Topsoil will be segregated fromthe waste materials and stockpiled for later use in a manner thatprotects the stockpiled material from wind and water erosion. Allstockpiles will be placed in designated areas out of prominentdrainageways and shall be constructed to avoid the ponding ofsurface runoff.

1.3- Excavation

Excavation will consist of the earth movement required to achievethe lines, grades and dimensions shown in the Construction Drawingsor designated by the Engineer. All necessary precautions shall betaken to preserve the material below and beyond the lines of allexcavation in the soundest possible condition. Where required tocomplete the Work, all excess excavation required to removeunsuitable or objectionable materials and overexcavation shall be

2

refilled with suitable materials acceptable to the Engineer. Noexcavation will be made in frozen materials.

All unsuitable materials removed from the excavations shall bedisposed of in designated waste or spoil areas. All, suitablematerial removed from excavations shall be placed as fill in theconstruction of the embankments or shall be stockpiled at adesignated location for later use. No suitable excavated materialshall be wasted without the Engineer's permission.

1.4 Placement of Fill

The placement of fill will consist of the earth movement, placementand compaction of suitable earthen materials as required to achievethe lines,- grades, dimensions and density specified in theConstruction Drawings and Construction Specifications.

Prior to the placement of fill, the pond foundation and areasunderlying embankments shall be prepared according to the methodsspecified in Section 1.1, Clearing and Grubbing. The base of thepond and the ground surface over which fill is to be placed willthen be scarified to a minimum depth of eight inches, watered oraerated as necessary to bring the moisture content to within plusor minus 2 percentage points of the optimum moisture content andcompacted to a depth of six inches at a density not less than 95percent Standard Proctor Maximum Dry Density as determined by ASTMD-698.

Fills shall be constructed to the lines, grades, and cross sectionsindicated on the Construction Drawings. Material used for theconstruction of fills shall be designated as suitable by theEngineer and shall be free of organic matter, frozen material, androcks greater than 4 inches in the maximum dimension. Anyunsuitable material placed as fill will be removed and replaced bysuitable material at the Contractor's expense.

All suitable material used as fill shall be placed in successivesix-inch (compacted) horizontal layers. All suitable materialshould be worked to a uniform moisture content within plus or minus2 percent of the optimum moisture content. Material deficient inmoisture shall be watered and mixed thoroughly, and material wet ofoptimum shall be worked and aerated until an acceptable moisturecontent is achieved. Whenever possible water shall be added at theborrow area. The distribution of materials throughout thecompacted earthfill shall be- such that it will be free from lenses,pockets, streaks, and layers of material differing substantially intexture or gradation from the surrounding fill-material.

Each successive layer shall be compacted to not less than 95percent of Standard Proctor Maximum Dry Density as determined byASTM D-698. If the specified density is not achieved, the areawill be reworked to plus or minus two percent of the optimummoisture content and recompacted to the specified density.

3

1.5 Field Testing and Quality Assurance

Field density testing will be conducted to insure that thespecified compaction is achieved during construction. Densitytests will be performed according to one or more of the followingmethods:

Standard Test Methods for Density ofSoil Aggregates in Place by NuclearMethods - ASTM D2922-81

Test for Density of Soil in Place bythe Sand-Cone Method - ASTM D1556-82

Test for Density of Soil in Place bythe Rubber-Balloon Method - ASTM D2167-84

Field density tests will be performed at a rate of one test foreach 10,000 sq ft of compacted foundation area and at a rate ofthree tests for each layer of compacted fill material. Fill areasfailing to meet the specified compaction criteria will be reworkedand recompacted to the specified density. All work will beconducted under the supervision of an engineer familiar with thedesign and construction of compacted earth structures who will workwith the Contractor to insure that all work is in accordance withthe Plans and Specifications.

2.0 LEAK DETECTION SYSTEM INSTALLATION AND TESTING

This section includes specifications for the work associated withthe installation and testing of the leak detection trenches,piping, trench backfill, and optional sand drainage layer (requiredfor the single liner optional design, Option A).

2.1 Trenching and Compaction of Trenches

The Contractor shall excavate pipe trenches in the locations and tothe grades and lines shown in the Construction Drawings or asspecified by the Engineer or Construction Specifications. Allexcavated materials not required or not suitable for backfill shallbe stockpiled as directed by the Engineer. Any unsuitable materialat grade level as'determined by the Engineer shall be undercut andreplaced by suitable material.

The trenches shall not be used to dewater the excavation for thepond cells and shall be kept free of water. The base and sides ofthe trench shall be accurately graded and compacted to 95 percentof Standard Proctor Maximum Dry Density as determined by ASTM D-698and shall be cleaned of all irregularities, protruding rocks andloose uncompacted soils or other debris prior to the installationof the leak detection piping.

4

2.2 Installation of Leak Detection Piping

a. Option A

After the Engineer's approval of the location, grade andcompaction of the pipe trenches, the Contractor shall installthe leak detection piping to the grades and lines shown in theConstruction Drawings or as specified by the Engineer orConstruction Specifications.

The perforated leak detection collector pipes shallconform toASTM D3034, SDR 35 and be provided with two horizontal rows of½- inch diameter holes spaced approximately 5 inches apart.The horizontal perforations shall be placed at a 120 degreeangle from the center of the pipe and shall be approximately 1inch above the pipe invert. The piping shall be checkedbefore being lowered into the trench to insure that no foreignmaterial, manufacturer's defects or cracks exist that mightprevent proper joining of the pipe or its operation as acollector drain.

The pipe and fittings will be placed in the trench in a mannerthat will prevent damage to the pipe. Pipes shall be joinedby approved solvent welding methods in strict accordance withthe manufacturer's recommendations. The pipe will be placedin the trench and rotated to keep the perforations one inch(1") from the trench bottom to provide a uniform flow sectionfor *the conveyance of liquid. Pipe laying and backfillingwill be conducted in a manner that will insure that vehiclesand heavy machinery are not operated over the installed pipelocations.

A geotextile filter cloth shall be placed to completelyenclose the 4-inch perforated pipe. The filter cloth shall bea nonwoven 100 percent polyester material having a weight ofat least 0.5 lb/sq yd and a tensile strength of 170 lbs inaccordance with ASTM D751 Grab Method. The filter cloth shallbe placed in accordance with the manufacturer'sspecifications. The working surface shall be leveled andcompacted and all sharp objects removed prior to rolling outthe filter cloth. All joints shall be overlapped inaccordance with the manufacturer's specifications. TheContractor shall insure that equipment traffic or backfillplacement operations do not damage the filter cloth or disruptthe overlapped joints. Punctured sections of filter clothshall be patched, and separated joints shall be reoverlappedprior to backfilling.

b. Option B

After the Engineer's approval of the location, grade andcompaction of the pipe trenches and the installation of thesecondary geomembrane, the Contractor shall install the leakdetection piping to the grades and lines shown in the

5

Construction Drawings or as specified by the Engineer orConstruction Specifications.

The perforated leak detection collector pipes shall conform toASTM D3034, SDR 35 and be provided with two horizontal rows of½-inch diameter holes spaced approximately 5 inches apart.The horizontal perforations shall be placed at a 120 degreeangle from the center of the pipe and shall be approximately 1inch above the pipe invert. The piping shall be checkedbefore being lowered into the trench to insure that no foreignmaterial, manufacturer's defects or cracks exist that mightprevent proper joining of the pipe or its operation as acollector drain.

The pipe and fittings will be placed in the trench in a mannerthat will prevent damage to the pipe. Pipes shall be joinedby approved solvent welding methods in strict accordance withthe manufacturer's recommendations. The pipe will be placedin the trench and rotated to keep the perforations one inch(1") from the trench bottom to provide a uniform flow sectionfor the conveyance of liquid. Pipe laying and backfillingwill be conducted in a manner that will insure that vehiclesand heavy machinery are not operated'over the installed pipelocations.

A geotextile filter cloth shall be placed to completelyenclose the 4-inch perforated pipe. The filter cloth shall bea nonwoven 100 percent polyester material having a weight ofat least 0.5 lb/sq yd and a tensile strength of 170 lbs inaccordance with ASTM D751 Grab Method. The filter cloth shallbe placed in accordance with the manufacturer'sspecifications. The working surface shall be leveled andcompacted and all sharp objects removed prior to rolling outthe filter cloth. All joints shall be overlapped inaccordance with the manufacturer's specifications. TheContractor shall insure that equipment traffic or backfillplacement operations do not damage the filter cloth or disruptthe overlapped joints. Punctured sections of filter clothshall be patched and separated joints shall be reoverlappedprior to backfilling.

2.3 Leak Detection Taps

The 4-inch diameter PVC leak detection taps shall be placed in thelocations and to the grades and lines shown in the ConstructionDrawings and as specified by the Engineer. The leak detection tapswill consist of 4-inch Schedule 40 PVC pipe which shall conform toASTM D1785-83, Schedule 40. The leak detection tap fittings shallconform to ASTM D2466-78, Schedule 40.

The leak detection tap shall be installed between the syntheticmembrane liners over the geonet and anchored by stabilizer strapsas shown in the Construction Drawings or as specified by theEngineer. Care will be taken during installation to insure that

6

the leak detection tap and fittings are securely joined to theperforated pipe, that the joints remain secure throughoutconstruction, and that the tap is securely fastened to theembankment lining materials as specified.

At all times during construction, the Contractor will beresponsible for the protection of the integrity of the leakdetection tap. If for any reason the tap or adjoining fittings aredamaged, the Contractor shall replace the tap and fittings at hisown expense.

2.4 Backfilling

The pipe, trenches and filter cloth shall be inspected and approvedby the Engineer prior to backfilling. After the Engineer'sapproval, the Contractor shall place coarse sand meeting thefollowing specifications as backfill around the filter clothwrapped pipe:*

Sieve Size Percent Passing (Wt)

3/8 inch 100No. 4 95 - 100No. 8 80 - 100No. 16 60 - 90No. 30 25 - 65No. 50 10 - 30No. 100 2 - 10No. 200 0 -5

*Note: This sand specification is provided as an example of a typicalcoarse sand gradation. The actual gradation specification forthe sand to be used will depend on the availability ofmaterials. The installed sand will have a similar gradation andwill have a permeability at least 100 times greater than thecompacted-underlying soils.

Care will be taken during backfilling operations to insure thatbackfill is placed around the pipe to provide a sound pipe beddingwith a uniform contact surface for pipe support. The sand backfillshall be placed to the grades and lines shown in the ConstructionDrawings and will be compacted using a hand tamper as directed bythe Engineer. During the placement and compaction of trenchbackfill care will be taken to avoid the displacement, deflection,cracking or other damage to the pipe. Vehicle and heavy equipmenttraffic will not be allowed to cross the trench area unlessapproved by the Engineer. Any pipe broken during construction willbe replaced by the Contractor at the Contractor's expense.

7

2.5 Leak Detection Sand

a. Option A

This specification pertains to the installation of the leakdetection sand over the base of the pond as required underOption A (single liner option).

A uniform layer of coarse sand meeting the following gradationspecifications will be placed over the pond bottom to thegrades and lines shown in the Construction Drawings or asspecified by the Engineer:*

Sieve Size Percent Passing (Wt)

3/8 inch 100No. 4 95 -100No. 8 80 -100No. 16 60 -90No. 30 25 -65No. 50 10 -30No. 100 2 -10No. 200 0 -5

*Note: This sand specification is provided as an example of a typicalcoarse sand gradation. The actual gradation specification forthe sand to be used will depend on the availability ofmaterials. The installed sand will have a similar gradation andwill have a permeability at least 100 times greater than thecompacted underlying soils.

The Contractor shall be responsible for supplying materialmeeting the requirements of this section. Material to be usedfor leak detection sand shall be identified, sampled, testedand approved by the Engineer prior to its placement.

The sand layer shall not contain clay lumps, brush, roots,topsoil1 or other organic, perishable or deleterious matter.If for any reason the Contractor places material which doesnot meet the requirements contained in this section, all suchmaterials shall be removed and replaced with satisfactorymaterial at the Contractor's expense.

The leak detection sand shall be spread in one-foot lifts andcompacted to 90 percent relative density according toASTM-2049., The sand when compacted to 90 percent relativedensity, shall have a coefficient of permeability of at least0.02 centimeters per second when subjected to a falling headpermeability test.

It will be the responsibility of the Contractor to keep theprepared surface in an acceptable condition until installationof the pond lining is completed.

8

2.6 Field Testing and Quality Assurance

All phases of construction will be supervised by an Engineerfamiliar with the design plans and specifications. The supervisionwill include the inspection of the quality of materials andworkmanship and the performance or supervision of field testing andsurveying. Inspecting and testing methods for quality control ofthe work described in this section will include the performance offield density tests, gradation tests, the inspection of pipe andfilter wrap and surveying to insure proper grade lines.

Field density tests by the methods listed in Section 1.5 will beperformed at a rate of one test for each 200 linear foot ofcompacted trench. Sections of trench not meeting the compactionspecifications shall be reworked until satisfactory compaction isachieved.

The density of the compacted leak detection sand will be determinedaccording to ASTM-2049 at a rate of one test for each 10,000 sq ftof compacted surface. Areas failing to meet the specificationswill be reworked until satisfactory compaction is achieved.

Trench and pipe grades will be verified by means of a field surveyof each completed lateral prior to backfilling.

2.7 Testing of the Leak Detection System

a. Option A

A test of the installed leak detection system will beperformed following construction and prior to the placement ofthe primary geomembrane to determine the efficiency andresponse time of the system. The test will be carried outunder the supervision of the Engineer.,

The test will consist of the introduction of a steady flow ofwater at least fourteen locations in each pond. The locationsand fl~ow rates shall be determined by the Englineer but will beof adequate scope to thoroughly test the function of each leakdetection lateral and tap. The sumps at the base of the leakdetection taps will b e continuously monitored during the testto determine the response time for each test. If no waterreaches the tap within a reasonable time, the system will bechecked and repaired if necessary, then retested. A log ofthe method and results of each test will be maintained by theEngineer. The system will not be considered acceptable untileach lateral and tap is shown to be fully functional.

b. Option B

A test of the installed leak detection system will beperformed following construction and prior to the placement ofthe primary -geomembrane to determine the efficiency and

9

response time of the system. The test will be carried outunder the supervision of the Engineer.

The test will consist of the introduction of a steady flow ofwater in at least six locations in each pond. The locationsand flow rates shall be determined by the Engineer but will beof adequate scope to thoroughly test the function of each leakdetection lateral and tap. The sumps at the bases of the leakdetection taps will be continuously monitored during the testto determine the response time for each test. If no waterreaches the tap within a reasonable time, the system will bechecked and repaired if necessary then retested. A log of themethod and results of each test will be maintained by theEngineer. The system will not be considered acceptable untileach lateral and tap is shown to be fully functional.

3.0 LINER INSTALLATION AND TESTING

The solar evaporation pond lining system includes two designoptions and two material options. Design Option A consists of twogeomembranes lining the side slopes and a single geomembrane linerover a sand leak detection system on the pond bottom. DesignOption B includes the installation of a double geomembrane linerover the entire pond interior. Both options include the use ofgeonet between the synthetic liners wherever the double liner isused.

Lining material options for the primary geomembrane include HDPE orHypalon (TM) as alternatives. The secondary geomembrane willconsist of 20 mil PVC. Material, installation and testingspecifications for each material are provided in the followingsections.

3.1 PVC Underliner

3.1.1 Material Specifications

The PVC underliner (secondary geomembrane) shall have a nominalthickness of 20 mils. The liner shall be a single-ply constructionhaving polyvinyl chloride as its principle polymer and shall meetthe requirements of these spec-ifications. The physical propertiesof the PVC underliner shall conform to the properties andspecifications listed in Table CS-I. The materials supplied underthese specifications shall be first quality-products manufacturedspecifically for. the purposes of this work and shall have beensatisfactorily demonstrated by prior use to be suitable for suchpurposes.

The PVC lining material shall be formulated and manufactured from100 percent polyvinyl chloride resin and be specifically compoundedfor use in hydraulic structures. Reprocessed or reground materialshall not be used. No set up or trim materials that are foreign tothe formulation shall be used. The liner shall be so produced asto be free of holes, undispersed raw materials or blisters. Any

10

Table CS-I. Physical Properties of Polyvinyl Chloride (PVC) Membrane Liner

Property

Thickness (mils) (Nominal ± 5%)

Specific Gravity, min.

Tensile Strength (psi), min.(Breaking Factor, lbs/in width, min.)

Elongation @ Break (%), min.

Modulus @ 100% Elongation (psi), min.(lbs/in width min.)

Tear Resistance (lbs/in), min.(lbs, min.)

Low Temperature ('F)

Dimensional Stability (% change), max.

Water Extraction (% loss), max.

Volatility (% loss), max.

Resistance to Soil Burial (% change), max.

Tensile StrengthElongation @ BreakModulus @ 100% Elongation

Hydrostatic Resistance (psi), min.

Factory Seam Requirements*

Bonded Seam Strength(factory seam, breaking factor, ppi width)

Test Method

ASTM D-1593

ASTM D-792

ASTM D-882

ASTM

ASTM

D-882

D-882

ASTM D-1004

ASTM D-1790

ASTM D-1204(212 0 F, 15 min.)

ASTM D-3083

ASTM D-1203

ASTM D-3083

ASTM D-751

ASTM D-3083(as modified inAppendix A)

Specified Values

20

1.23

2,30046

325

1,000(20.0)

300(6.0)

-15

3.5

0.35

0.90

-5-20+20

60

36.8

* Factory bonded seam strength is the responsibility of the fabricator.

11

such defect shall be repaired using the thermoplastic sheeting andmanufacturer's approved method.

The roll goods shall be factory fabricated into panel s not toexceed 35,000 S.F. each. Size and seam direction shall be such asto reduce the amount of field seaming required during installation.All factory seams shall be a minimum of 1 inch in width and shallbe ,of sufficient bonded strength to obtain film separation upontensile testing. Transportation, handling and storage proceduresshall be planned to prevent damage. Material shall be stored in asecured area and protected from adverse weather.

3.1.2 Installation

This work consists of furnishing and installing a polyvinylchloride (PVC) plastic lining' where shown on the ConstructionDrawings or directed by the Engineer. The work shall includeground preparation, excavation, backfill and compaction of theanchor trench. Installation shall be performed under the directionof an installation Contractor who has installed a minimum of500,000 sq ft of similar lining material. The installationContractor shall be in charge of the installation and shall beresponsible for the work performed.

The surface (substrate) to receive the liner shall be free of sharpobjects that could damage the lining. All vegetation must beremoved. Underlying soil may need to be sterilized with anapproved defoliant. Prior to the commencement of the installation,the surface to be lined shall be jointly inspected by the Engineer,.excavation Contractor and the liner installation Contractor, andthe installation Contractor shall certify in Writing that theprepared surface on which the liner is to be placed is acceptable.No installation of liner shall commence until this certification isfurnished to the Engineer.

The installation Contractor shall furnish shop drawings andproposed method of installation for the approval of the Engineer.Written approval of the Engineer shall be obtained beforeproceeding with the work. The drawings shall show extent, sizesand details of the liner panels, including the position of allvents and indicating the location of all seams. Except for specialrequirements due to configuration and/or terminating the lining,the maximum use of large-sized panels shall be made.

The PVC lining shall be distributed over the surface in such amanner that sufficient excess lining material is available toaccommodate normal shrinkage and settlement, but not excessive tothe extent that large folds left in the lining material could causeit to break. The liner shall be installed iria relaxed conditionand shall be free of stress or tension upon completion of theinstallation. Stretching of the liner to fit is not permissible.The Contractor shall insure that equipment traffic or backfillplacement operation does not damage the PVC liner or disrupt theoverlapped joints.

12

The liner shall be sealed to all structures and other openingsthrough the lining in accordance with details shown on the drawingsubmitted by the Contractor and approved by the Engineer. Factoryfabricated pipe seals shall be used to seal all pipes penetratingthe liner.

The liner shall be anchored in a trench in accordance with thedetails shown on the Construction Drawings. Excavated materialshall be backfilled after the liner is keyed into the trench in6-inch lifts compacted to 95 percent Standard Proctor Maximum DryDensity using hand tampers.

Lap joints shall be used to seal factory fabricated panels of PVCtogether in the field. All field joints between sections of PVClining shall be made with an approved cold-applied solvent oradhesive. Lap joints shall be formed by lapping 6-inches minimumof the film. Actual welded surface shall be a minimum of 4 inches.The contact surfaces of the panels shall be wiped clean to removedirt and other foreign materials prior to applying adhesives.Sufficient cold-applied vinyl-to-vinyl bonding adhesive shall beapplied to the contact surfaces in the joint area and the surfacesjoined under pressure immediately thereafter. During the joiningprocedure, any wrinkles shall be smoothed out to insure a goodcontact between the surfaces to be joined.

Any portion of the lining damaged during installation by any causeshall be removed or repaired by using an additional piece of liningto patch the damaged area. The patch shall be made of roundedcorners, large enough to extend 4 inches in all directions from thepuncture. The joining of the patch to the liner shall be inaccordance with the field joint procedure discussed above.

3.1.3 Testing and Quality Assurance

The installation of the liner materials shall be under thecontinuous supervision of an installation Contractor who is trainedand who has had considerable experience in the installation of PVClining materials. A Fabricator Field Service Representative willbe required during the liner installation if the installation isnot done by an authorized installer. The Contractor will bear theexpense of the Field Service Representative.

Upon completion of the installation, the lining shall be jointlyinspected by the Contractor and the Engineer to determine theintegrity of the field seams as well as the general condition ofthe lining. The Engineer, at his discretion, may conduct tests tothe field seams that will demonstrate to his satisfaction that theparent lining material will break prior to the separation of thefield seams. Any lining surface damaged due to scuffing,penetration by foreign objects, or distress from rough subgradeshall, as agreed to by the Contractor and Engineer, be replaced orcovered and sealed with an additional layer of PVC.

13

Upon satisfactory inspection and testing results and acceptance bythe Owner, the installation Contractor shall warrant in writingthat the work is free of any defects in workmanship and/ormaterials, that the lining membrane will meet or exceed themanufacturer's specifications for the material.

3.2 Hypalon (TM) Primary Geomembrane


If Hypalon (TM) is used as the primary geomembrane lining, thematerial shall be three-ply laminated industrial grade reinforcedHypalon (TM), of new, first-quality products designed andmanufactured specifically for' the purpose of this work, and shallhave been satisfactorily demonstrated by prior use to be suitableand durable for such purposes. The manufacturer shall haveproduced, and have in service in similar applications for a periodof not less than one (1) year, at least one million (1,000,000)square yards-of this material.

The material shall be constructed of thermoplastic elastomericlining material consisting of one ply of fabric reinforcementencapsulated by two plies of Hypalon rubber sheeting. Thereinforcing fabric is a 10 x 10, 1000 denier polyester scrim with aplain weave. The rubber sheeting is compounded using DuPont'sHypalon 45 rubber polymer and specifically formulated for low waterabsorption.

The specifications and physical properties of the Hypalon primarygeomembrane liner are provided in Table CS-2. The Hypalonmaterials shall be manufactured from domestic Hypalon resin andspecifically compounded for use in hydraulic facilities.Reprocessed materials shall not be used.

A material with a nominal thickness of 36 mil shall be used.Certification test results showing that the sheeting meets thespecifications shall be supplied by the manufacturer on request.

The manufacturer shall furnish complete written instructions forthe storage, handling, installation, seaming and inspection of thematerial in compliance with this specification and conforming tothe conditions of the warranty.

The liner material shall be produced so as to be free of holes,blisters, undispersed raw materials or any sign of contamination byforeign matter. Any such defect shall be repaired in accordancewith the manufacturer's recommendations. Transportation, handlingand storage procedures shall be planned to prevent damage.Material shall be stored in a secured area and protected fromadverse weather.

14

Table CS-2. Physical Properties of Hypalon (TM) Membrane Liner

Property Test Method Specified Values

Gauge, nominal (mils)

Piles, reinforcing 10 x 10 1000d polyester

36

1

Thickness, minimum (mils)

OverallOver scrim

ASTM D-751

Optical Method(see Appendix,Part 1)

3411

200Breaking strength - fabric, minimum (lbs) ASTM D-751,Method A

Tear strength (pounds, minimum)

1.2.

InitialAfter aging

Low temperature flexibility (°F)

Dimensional stability (each directionpercent change maximum)

Volatile loss, maximum, for 30 milunsupported sheet (percent)

Resistance to soil burial (maximum percentchange from original values)

a. 30-mil unsupported sheet1. Breaking strength2. Elongation at break3. Modulus at 100% elongation

b. Membrane fabric breaking strength

Hydrostatic resistance, minimum (psi)

Ply adhesion, each direction,minimum (lbs/in)

ASTM D-751,Modified (seeAppendix, Part 2)

ASTM D-2136, 1/8in. mandrel,4 hrs - Pass

ASTM D-1204212'F, 1 hr

ASTM D-1203,Method A

8035

-40

2

0.5

ASTM D-3084 (perASTM paragraph9.5)

ASTM 0-751,Method A

ASTM D-751,Method AProcedure 1

ASTM D-413,Machine MethodASTM D-413,Modified Method(see Appendix,Part 3)

5202025

250

8

10

15

Table CS-2. Physical Properties of Hypalon (TM) Membrane Liner (Continued)

Property Test Method Specified. Values

Water absorption, maximum, 30 milunsupported sheet (percent weight gain)

ASTM D-47114 days @ 70'F30 days @ 70'F120 days @ 70'F14 days @ 158°F30 days @ 158°F120 days @ 158 0 F

1.52.02.0

30.030.030.0

16

3.2.2 Installation

This work consists of furnishing and installing a reinforcedHypalon (TM) liner to the limits shown on the Construction Drawingsand as specified herein. The work shall include substratepreparation, excavation, backfill and compaction of the anchortrench. Installation of the liner shall be performed by aContractor approved and licensed for installation work by thelining manufacturer. A copy of the approval or licensing documentshall be submitted to the Engineer upon request. The installationContractor shall have installed a minimum of 2,500,000 sq ft of thespecified liner.

The installation Contractor shall furnish shop drawings andproposed method of installation for the approval of the Engineer.Written approval of the Engineer shall be obtained beforeproceeding with the work. The drawings shall show extent, sizesand details of the liner panels, including the position of allvents and indicating the location of all seams. Except for specialrequirements due to configuration and/or terminating the lining,the maximum use of large-sized panels shall be made.

The surface (substrate) to receive the liner shall be free of sharpobjects that could damage the lining. Prior to the commencement ofthe installation, the surface to be lined shall be jointlyinspected by the installation Contractor and the Engineer', and theinstallation Contractor shall certify in writing that the preparedsurface on which the liner is to be placed is acceptable. Noinstallation of liner shall commence until this certification isfurnished to the Engineer.

The Hypalon lining shall be distributed over the surface in such amanner that sufficient excess lining material is available toaccommodate normal shrinkage and settlement, but not excessive tothe extent that large folds left in the lining material could causeit to break. The liner shall be installed in a relaxed conditionand shall be free of stress or tension upon completion of theinstallation. Stretching of the liner to fit is not permissible.The Contractor shall insure that equipment traffic, pipeinstallation or backfill placement does not damage the Hypalonliner or disrupt the overlapped joints.

The liner shall be sealed to all structures and other openingsthrough the lining in accordance with details shown on the drawingsubmitted by the.Contractor and approved by the Engineer. Factoryfabricated pipe seals shall be used to seal all pipes penetratingthe liner.


17

Field seams shall be used to seal factory fabricated panels ofH-ypalon together in the field. All field~.joints between sectionsof H-ypalon lining shall be made on a supporting smooth surface suchas a board, and unless the weather is warm and the sun is shiningbrightly, heat guns shall be used to make the sealing temperatureat least 100 degrees F. Lap joints shall be formed by lapping 4inches minimum of the reinforced portion of the film. The contactsurfaces of the panels shall be wiped clean to remove all dirt,dust, or other foreign materials and the matting surfaces will bescrubbed with Trichlorethylerie. The surface shall be scrubbed inonly one direction and only clean towels or paper towels used. Abodied solvent Hypalon adhesive will be applied sufficiently thatthe entire bottom liner surface is covered and that a bead of theadhesive will extend beyond the seam, edge. The two panels to bejoined must be pulled tight to keep the edges to be seamed smoothand wrinkle free. Immediately upon applying the adhesive the twolining surfaces shall be joined together and rolled smooth withhand rollers.

No field seaming shall be undertaken at an air temperature lessthan 45 degrees F. unless the installation Contractor provideswritten documentation from the manufacturer or manufacturer'srepresentative that the air temperature and the seaming method usedwill not degrade the integrity of the lap joint.

In light rain, portable protective structures and/or other methodsshall be used to maintain a dry sealing surface. When field seamsare affected by rain, installation shall be halted.

Any portion of lining damaged during installation by any causeshall be removed or repaired by using an additional piece of liningto-.patch the damaged area. The patch shall be made of roundedcorners, large enough to extend 4 inches in all directions from thepuncture. The joining of the patch to the liner shall be inaccordance with the field joint procedure discussed above.


The installation of the liner materials shall be under thecontinuous supervision of an installation Contractor who is trainedand who has had considerable experience in the installation ofHypalon lining materials.

Field seams shall be inspected continuously as seaming is done andany faulty area repaired immediately. All field seams will be 100percent inspected by the installation Contractor and/or themanufacturer's technical representative to insure the integrity ofthe seams.

Upon completion of the installation, the lining shall be jointlyinspected by the Contractor and the Engineer to determine theintegrity of the field seams as well as the general condition ofthe lining.

18

All seams must pass a 100 percent air lance inspection. TheEngineer, at his discretion, may conduct tests on the field seamsthat will demonstrate to his satisfaction that the parent liningmaterial will break prior to the separation of the field seams.The shear strength of the field seam shall be tested by obtaining a4-inch wide strip 8 inches long plus seam width across the finishedseam. The seam must be stronger when tested than the parentmaterial on either side of the seam. If the seam test samplefails, two more samples are to be tested at 10 feet on each side ofthe sample. When acceptable samples are obtained, the sample testhole is to be patched as specified in the field seaming procedureabove.

Any lining surface damaged due to scuffing, penetration by foreignobjects, or distress from rough subgrade shall, as agreed to by theContractor and Engineer, be replaced or covered and sealed with anadditional layer of Hypalon.


3.3 High Density Polyethylene (HDPE) Primary Geomembrane


If high density polyethylene (HDPE) is used for the primary.geomembrane lining, the material shall be a high densitypolyethylene containing no additives, fillers, or extenders.Carbon black 2 percent-3 percent shall be added to the resin forultraviolet resistance according to ASTM D 1603. The membraneliner shall consist of unsupported polyethylene liner manufacture~dspecifically for the purpose of liquid containment in hydraulicstructures.

The manufacturer/installer must have at least five (5) yearscontinuous experience in the manufacture and installation of thistype of liner and must have manufactured and installed at least10,000,000 sq ft of the material specified herein.

The specifications and physical properties of the (HOPE) primarygeomembrane liner are provided in Table CS-3. The liner materialshall be so produced as to be free of holes, blisters, undispersedraw materials, or any sign of contamination by foreign matter. Anysuch defect shall be repaired using the extrudate welding techniquein accordance with the manufacturer's recommendations.

A material with a nominal thickness of 60 mil shall be used.Certification test results showing that the sheeting meets thespecifications shall be supplied by the manufacturer of theproduct. Lining material samples and minimum specifications shallbe submitted to the Engineer prior to bid date. The specification

19

Table CS-3. Physical Properties of 60 Mil High Density Polyethylene (HDPE)Membrane Liner

Property

PHYSICAl

Gauge of Material (mils)

Specific Gravity (g/cc)

Minimum Tensile Properties

Tensile @ Yield (psi)Tensile @ Break (psi)Elongation @ Yield (%)Elongation @ Break (%)Modulas of Elasticity (psi)

Tear Resistance, Minimum (psi)

Low Temp. Brittleness (°C)

Resistance to Soil Burial (%)

Tensile @ YieldTensile @ BreakElongation @ YieldElongation @ BreakModulas of Elasticity

Environmental Stress Crack Res. (hrs)

Carbon Content (%)

Carbon Dispersion (score)

Melt Index (g/l0m)

Puncture Resistance (lbs)

Water Vapor Transmission(GM-MIL/24 HR/100 in 2/90°/RH

Hydrostatic Resistance (psi)

Test Method

L PROPERTIES

ASTM D-1593

ASTM D-792 A

ASTM D-638

ASTM D-1004

Die C

ASTM D-746 B

ASTM D-3083(NSF SPEC 54 )

Specified Values

60 (±5%)

> 0.935

2,0003,800

13600

80,000

7O0

-75

+/- 10+/- 10+/- 10+/- 10+1- 10

2,000

2-3

A-2

< 1.0

90

0.5

450

ASTM(NSF

ASTM

ASTM

ASTM

FTMS

D-1693SPEC 54),

D-1603

D-3015

D-1238

101 C

ASTM D-751 A

20

Table CS-3. Physical Properties of 60 Mil High Density Polyethylene (HDPE)Membrane Liner (Continued)

Property

NATIONAL SEAL SEAMING

Bonded Seam Strength, Shear (ppi)

Bonded Seam Strength, Peel (ppi)

Peel Adhesion, Minimum (ppi)

Resistance to Soil Burial

Bonded Seam Strength Change (%)Peel Adhesion

Test Method

PROPERTIES

ASTM D-3083

ASTM D-413

ASTM D-413

ASTM D-3083

Specified Values

130 (min.)

90 (min.)

Film Tear Bond

-20Film Tear Bond

21

sheet shall give minimum physical properties and test methodsemployed for on-site quality control of seams. A copy of themanufacturer' s quality control manual shall be submitted forapproval or alterations.

The manufacturer shall furnish complete written instructions forthe storage, handling, installation, seaming and inspection of thematerial in compliance with this spec~ification and conforming tothe conditions of the warranty.

3.3.2 Installation

This work consists of furnishing and installing a high densitypolyethylene (HDPE) liner to the limits shown on the ConstructionDrawings and as specified herein. The work shall include substratepreparation, excavation, backfill and compaction of the anchortrench. Installation of the liner shall be performed by aContractor approved and licensed for the installation work by thelining manufacturer. A copy of the approval or licensing documentshall be submitted to the Engineer upon request. The installationContractor shall have installed a minimum of 2,500,000 sq ft of thespecified liner.

The installation Contractor shall* furnish shop drawings andproposed method of installation for the approval of the Engineer.Written approval of the Engineer shall be obtained beforepro'ceeding with the work. The. drawings shall show extent, sizesand details of the liner panels, including the position of allvents and indicating the location of all seams. Except for specialrequirements due to configuration and/or terminating the lining,the maximum use of large-sized panels shall be made.

The surface (substrate) to receive the liner shall be free of sharpobjects that could damage the lining. Prior to the commencement ofthe installation, the surface to be lined shall be jointlyinspected by the installation Contractor and the Engineer and theinstallation Contractor shall certify in writing that the preparedsurface on' which the liner is to be placed is acceptable. Noinstallation of liner shall commence until this certification isfurnished to the Engineer.

The HDPE lining shall be distributed over the surface in such amanner that sufficient excess lining material is available toaccommodate normal shrinkage and settlement, but not excessive tothe extent that large folds left in the lining material could causeit to break. The liner shall be installed in a relaxed conditionand shall be free of stress -or tension upon completion of theinstallation. Stretching of the liner to fit is not permissible.The Contractor shall *insure that equipment traffic, pipeinstallation or backfill placement does not damage the HDPE lineror disrupt the overlapped joints.

The liner shall *be sealed to all structures and other openingsthrough the lining in accordance with details shown on the drawing

-2)2

submitted by the Contractor and approved by the Engineer. Factoryfabricated pipe seals shall be used to seal all pipes penetratingthe liner.


Field seams shall be made by overlapping adjacent sheets a minimumof eight inches (8") and extruding a ribbon of extrusion-joiningresin no less than 1.0 inch in width between the overlapped sheetsor over the seam between the sheets where hand welds are required.Resin used for extrusion-joined sheets and-sheet to pipe shall beHDPE produced from the same material as the sheet resin. Physicalproperties shall be the same as those of the resin used in themanufacture of the HDPE liner. The resin shall be supplied inblack.

Prior to extrusion welding of the seams, all areas which are tobecome seam interfaces shall be cleaned of dust and dirt. Thes-lick surfaces of the HDPE sheet which are to become seaminterfaces shall be roughened with a wire brush or other acceptablemeans before extrudate is placed between the overlapping sheets orover a lapped seam. Extrusion joining shall riot take place unlessthe sheet is dry and shall not take place unless the ambienttemperature is above 45 degrees F and below 90,degrees F.

Joints between the lining sheets shall be field welded using themanufacturer's extrusion joining equipment and techniques. Thejoining procedure shall consist of softening the liner material byheated air. The temperature of the air impinging on the sheet forthis purpose shall range from 420 degrees F to 680 degrees F. Theexact temperature used shall be determined by the installationContractor and shall be in accordance with the manufacturer'srecommendations. Directly following the application of heat, aone-inch minimum width strip of the same high density polyethyleneresin from which the sheet is made shall be extruded between theoverlapped sheets. The temperature of the resin as it emerges fromthe extrusion die shall range from 428 degrees F to 536 degrees F.The overlapped sheets are then pressed together to form theextrusion joint.

On-site welding of the liner shall be carried out, by an extrusionwelding process. This process shall guarantee consistent weld seamquality within a wide range of ambient conditions. The controlsystem of the welding machines shall be extensively automated toenable monitoring of the welding process by the operatingpersonnel.

The welds shall be formed in one procedure by means of an automaticwelding machine, which preheats the welding surfaces to the desired

23

temperature, injects a ribbon of molten HOPE material and thenapplies contact pressure to the seam.-

Penetrations through the liner for pipe flashings, patches, etc.,shall be field welded using an extrusion hand welder. The joiningprocedure shall consist of softening the liner material by heatedair as described above. Directly following the application ofheat, a hot strip of the same material from which the sheet is madewill be extruded over the joint to produce the extruded joint.

Any required repair of small holes in the liner surface shall bemade with the extrusion hand welder. Liner material shall becleaned of all dirt, dust, and other foreign material, all smoothHOPE surfaces roughened, air heated to the prescribed temperature,and a strip of HDPE resin extruded over the hole to produce anextruded welded repair.

.All pipe penetrations shall be sleeved with HDPE pipe. Each HOPEpipe sleeve shall be sealed to the liquid-carrying pipe to preventleakage. The basin liner shall be anchored to a concrete collarsurrounding the penetration. An HOPE apron shall be extrusionwelded to the pipe sleeve and shall be extrusion welded to the basesheet outside of the area where the base sheet is anchored to theconcrete collar.


The installation of the liner materials shall be under thecontinuous supervision of an installation Contractor who is trainedand who has had considerable experience in the installation of HOPElining materials.

Quality control of liner installation shall consist of three mainareas of concentration:

1. Checking the sheets delivered to the site for transportdamages.

2. Inspection and continuous control of all welding processparameters.

3. Testing of the completed weld seams.

Test welds shall be run preceding all extensive welding to assuregood weld quality under the prevailing site conditions; these weldsamples shall be subsequently subjected to mechanical testing.Production of a quality welding seam starts with a preliminary testweld. The machine settings, pretreatment of the weld surfaces andadjustment to environmental effects shall be tested on a samplewelding seam. A hand-operable tensile testing machine shall. be onsite for confirmation of the joint's tensile strength using stripsamples.

24

The main prerequisite for good bonding shall be continuousmonitoring of the welding process parameters, such as hot airtemperature, welding speed and contact pressure. This is bestcarried out by specially trained personnel. Visual inspection ofthe welding surfaces, the welding process and the completed weld byexperienced plastic welders allows a reliable evaluation of seamquality. Field seams shall be inspected continuously as seaming isdone and any faulty area repaired immediately. All field seamswill be 100 percent inspected by the installation Contractor and/orthe manufacturer's technical representative to insure the integrityof the seams.

After installation, two major types of quality control shall beavailable for testing the seams:

- Destructive material tests of weld samples (spot check).

- Nondestructive material tests of all welding seams.

Because it would be uneconomical to conduct destructive tests onall weld seams, destructive tests shall be conducted only on a spotcheck basis. Extensive site experience has shown that two samplesdaily are sufficient for evaluation purposes.

Point stressing of the newly produced weld shall be sufficient tolocate areas of nonadhesion (i.e., not fully bonded). This shallbe accomplished by running a screw driver or similar device alongthe weld seam between the lower sheet and the extrudate.

Following installation, the large size of the completed linersystem permits testing only from the upper side of the liner.There will be two optional nondestructive testing procedures.utilized to evaluate the continuity of the completed lining system.

- Ultrasonic Testing: Ultrasonic testing shall provideinformation on the homogeneity of the welding seam.' Thethickness of the weld shall be tested for homogeneity andexclusions by the use of sound waves similar to ASTME164-74.

- Vacuum Test: Vacuum testing of the seal consists ofplacing the seal under a clear plastic suction cupattached to a vacuum pump. A foaming agent indicates theexact position of any leaks encountered.

Following completion of the installation, the lining shall bejointly inspected by the Contractor and Engineer to determine theintegrity of the field seams as well as the general condition ofthe lining.

Upon satisfactory inspection and testing results and acceptance bythe Owner, the installation Contractor shall warrant in writingthat the work i s f ree of any defects in workmanship and/or

25

materials, that the lining membrane will meet or exceed themanufacturer's specifications for the material.

3.4 HDPE Geonet


The geonet to be placed between the synthetic membrane liners forconducting leakage to the leak detection piping shall be a profiledhigh density polyethylene HDPE mesh. The geonet will be producedby extruding two sets of HDPE strands together to form adiamond-shaped net.

The manufacturer/installer must have a least five (5) yearscontinuous experience in the manufacture and installation of thistype of liner and must have manufactured and installed at least10,000,000 sq ft of the material specified herein.

The specifications and physical properties of the (HDPE) geonet areprovided in Table CS-4. The liner material shall be so produced asto be uniform and free of defects, blisters, undispersed rawmaterials, or any sign of contamination by foreign matter.

A material with a nominal thickness of 0.2 inches shall be used.Certification test results showing that the sheeting meets thespecifications shall be supplied by the manufacturer of theproduct. Lining material samples and minimum specifications shallbe submitted to the Engineer prior to the bid date. Thespecification sheet shall give minimum physical properties and testmethods employed, for on-site quality control of seams. A copy ofthe manufacturer's quality control manual shall be submitted forapproval or alterations.

The manufacturer shall furnish complete written instructions forthe storage, handling, installation, seaming and inspection of thematerial in compliance with this specification and conforming tothe conditions of the warranty.

3.4.2 Installation

This work consists of furnishing and installing a high densitypolyethylene (HDPE) geonet liner to the limits shown on theConstruction Drawings and as specified herein. Installation of theliner shall be performed by a Contractor approved and licensed forthe installation work by the lining manufacturer. A copy of theapproval or licensing document shall be submitted to the Engineerupon request. The installation Contractor shall have installed aminimum of 2,500,000 sq ft of the specified liner.

The installation Contractor shall furnish shop drawings andproposed method of installation for the approval of the Engineer.Written approval of the Engineer shall be obtained beforeproceeding with the work. The drawings shall show extent, sizesand details of the liner panels, including the position of all

26

Table CS-4. Material Specifications and Physical Properties of High DensityPolyethylene (HDPE) Geonet

Specification

Roll Length (Maximum) (ft)

Roll Width (+I in.-O in.) (ft)

Thickness (in)

S.F. in Roll (S.F.)

Weight Per Roll (lbs)

Weight Per S.F. (lbs/S.F.)

Specified Values

300

6.750

0M200

2,025

330

0.160

Property

Raw Material (All Domestic and Virgin Material)

Manufacturing

Color

Carbon Black (%)

Density & Polymer (g/CM3)

Melt Index (g/10 min.)

Tensil Strength (Mach. Direction) (lbs/in)

Tensil Strength (Trans. Direction) (lbs/in)

Elongation to Break (Mach. Direction) (%)

Elongation to Break (Trans. Direction) (%)

Porosity

U.V. Resistance

Transmissivity

Polyethylene

Extruded

Black

2

0.936

1.10

53

31

925

425

0.81 -0.84

Stable

See Tables

27

.4,

vents and indicating the location of all seams. Except for specialrequirements due to configuration and/or terminating the lining,the maximum use of large-sized panels shall bemade.

The HOPE geonet lining shall be distributed over the surface insuch a manner that sufficient excess lining material is availableto accommodate normal shrinkage and settlement, but not excessiveto the extent that large folds left in the lining material couldcause it to break. The liner shall be installed in a relaxedcondition and shall be free of stress or tension upon completion ofthe installation. Stretching of the liner to fit is notpermissible. The Contractor shall insure that equipment traffic,pipe installation or backfill placement does not damage the geonetliner or disrupt the joints.


The installation of the liner materials shall be under thecontinuous supervision of an installation Contractor who is trainedand who has had considerable experience in the installation ofGeonet lining materials.

Following completion of the installation, the lining shall bejointly inspected by the Contractor and Engineer to determine theintegrity of the field joints as well as the general condition ofthe lining.


28

THIS PAGE IS ANOVERSIZED DRAWING OR

FIGURE,THAT CAN BE VIEWED AT THE

RECORD TITLED:"MAP 1

SOLAR EVAPORATION PNDLOCATION MAP."

WITHIN THIS PACKAGE... ORBY SEARCHING USING THE

DOCUMENT/REPORT NO.

D-01




SOLAR EVAPORATION PONDSITE LAYOUT."


DOCUMENT/REPORT NO.

D-02




SOLAR EVAPORATION PONDCROSS SECTIONS."


DOCUMENT/REPORT NO.

D-03



RECORD TITLED:"MAP 4a

SOLAR EVAPORATION PONDDETAIL

(SINGLE LINER OPTION)"


DOCUMENT/REPORT NO.

D-04


TIFFIGURE,

[AT CAN BE VIEWED AT THERECORD TITLED:

"MAP 4bOLAR EVAPORATION POND

DETAIL(DOUBLE LINER OPTION."

SI


DOCUMENT/REPORT NO.

D-05




SOLAR EVAPORATION PONDCROSS SECTIONS."


DOCUMENT/REPORT NO.

D-06X

official: docket copy j · solar evaporation pond detail (double liner option) ii 5 6 17 20 21 24....

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