Riley_Pass_Final_Borrow_Soil_Resources_Bluffs_A_and_I.PDF

REPORT OF

Survey of Topsoil Borrow Resources for

Bluffs A and I Riley Pass Mining Area

AG-0355-D-10-0011

December 2010

Survey of Topsoil Borrow Resources for Bluffs A and I Riley Pass Mining Area

AG-0355-D-10-0011

Prepared for:

United States Department of Agriculture Custer National Forest Sioux Ranger District

Prepared by:

618 South 25th Street Billings, Montana 59101

(406) 248-9161 Fax (406) 248-9282

Tetra Tech Project No. 114-550424

Jeffrey R. Rice Environmental Group Manager

December 2, 2010

Survey of Topsoil Borrow Resources

Bluffs A and I, Riley Pass Mining Area Custer National Forest

Tetra Tech December 2, 2010 i

TABLE OF CONTENTS

1.0 INTRODUCTION

2.0 METHODS

2.1 Data Review

2.2 Field Investigations

2.3 Sample Collection

2.4 Laboratory Analyses

2.5 Soil Borrow Map Unit Development

2.6 Soil Suitability for Reclamation

3.0 EXISTING SOIL MAPPING

3.1 Bluff A

3.2 Bluff I

4.0 SOIL PROFILE RESULTS

4.1 Bluff A

4.2 Bluff I

5.0 LABORATORY ANALYTICAL RESULTS

5.1 Soil Physical Properties

5.2 Soil Acidity and Alkalinity

5.3 Specific Conductance (SC)

5.4 Sodium Adsorption Ratio (SAR)

5.5 Metals

5.6 Nutrient Content

6.0 SOIL SALVAGE CONCLUSIONS AND RECOMMENDATIONS

6.1 Bluff A

6.2 Bluff I

7.0 REFERENCES

LIST OF FIGURES

Figure 1 Survey Area Locations

Figure 2 Bluff A Previously Proposed Borrow Areas

Figure 3 Bluff A Soil Profile Locations

Figure 4 Bluff I Previously Proposed Borrow Areas

Figure 5 Bluff I Soil Profile Locations

Tetra Tech December 2, 2010 ii

LIST OF TABLES

Table 1 Preliminary Topsoil Suitability Criteria- Riley Pass Mining Area

Table 2 Soil Chemistry

Table 3 Borrow Soil Volume Estimate

LIST OF APPENDICES

Appendix A: Soil Map Unit and Series Descriptions

Appendix B: Soil Profile Descriptions

Appendix C: Laboratory Analytical Report

Tetra Tech December 2, 2010 1

1.0 INTRODUCTION

During September 2010, Tetra Tech completed a limited soil borrow resource assessment within the vicinity of Bluff A and Bluff I (Figures 1) of the former Riley Pass uranium mining area in the Cave Hills of Harding County, South Dakota. This work was conducted in accordance with the Riley Pass Removal Action Borrow Soil Characterization, Bluffs A and I Plan of Study (Tetra

Tech, 2010). This assessment was conducted to identify and quantify potential soil borrow areas for reclaiming these former uranium mine sites.

The specific objectives of the soil resource assessment included the following:

Describe soil profiles or pedons and document soil characteristics;

Sample and analyze physical and chemical properties of representative pedons in the project area; and

Evaluate soil suitability for reclamation (i.e. as a growth medium), propose suitable salvage depths of the soil found in the project area, and identify limiting characteristics.

This report describes the methods used by Tetra Tech to achieve the survey objectives, as stated above, and presents results of the September 2010 soil resources assessment.

Supporting information is included in the appendices of this report.

2.0 METHODS

The methods employed to collect and analyze soil resource data were generally consistent with plans of study prepared for similar projects in the western U.S. The methods employed to conduct the survey are described below.

2.1 Data Review

The following information was reviewed prior to initiation of the soil assessment:

Aerial photography and topographic mapping for the project area;

Soil survey information from Harding County (USDA, 2010);

Soil borrow suitability criteria as provided by the United States Forest Service (USFS) in the Statement of Work (USFS, 2010); and, Previous soil sample analytical data (MSE, 2010).

2.2 Field Investigations

This soil resource evaluation and inventory, including soil sample collection and laboratory analyses, were completed for potential borrow sites with suitable topsoil and subsoil chemical

Tetra Tech December 2, 2010 2 and physical characteristics for reclamation of adjacent disturbed areas. The project area for potential borrow areas included approximately 150 acres as shown on Figure 1. The Area investigated for Bluff A was approximately 100 acres and 50 acres for Bluff I.

The soil assessment was conducted in general accordance with the Riley Pass Removal Action

Borrow Soil Characterization, Bluffs A and I, Plan of Study (Tetra Tech, 2010). Specific soil pedon descriptions were conducted in general accordance with the guidelines provided by the

National Soil Survey Handbook (USDA, 2003) and the Soil Survey Manual, Handbook 18

(USDA, 1993). Map unit boundaries were identified by field observation and interpretation of aerial photographs, topographic maps, and other geographic models.

The Custer National Forest was previously mapped by the USDA Natural Resource

Conservation Service (NRCS) and USFS to a level of detail commensurate to an Order III

Survey (USDA, 2010). The soil map units for the Bluff A study area are presented as Cohagen-

Rock outcrop–Cabba variant complex, three to 100 percent slopes and the Cohagen fine sandy loam, 15 to 50 percent slopes.

The soil map unit for the Bluff I study area is also given as Cohagen fine sandy loam, 15 to 50 percent slopes and the Parchin-Bullock fine sandy loams, two to nine percent slopes. Map unit summaries and corresponding Soil Series descriptions are presented in Appendix A. These soils are presented as generally thin A horizons, three to six inches, over C or non-altered parent materials.

The databases and digital maps from these previous surveys were used to develop a conceptual model. The conceptual model was used in combination with aerial photographs to identify likely changes in soil conditions (map units) within the project area. The locations of soil profiles were selected to be representative of a map unit or to help determine the composition of a map unit. These sites were identified through review of aerial photographs, topographic maps, and site inspection. A backhoe was used to excavate the soil profile description sites. All soil profile locations were cleared by an on-site archeologist retained by the USFS prior to excavation.

Soil profiles were described using methods and abbreviations identified in the Field Book for

Sampling and Describing Soils (USDA, 2002), with modifications as noted in this section.

Complete or partial pedon descriptions were recorded on forms, which are included in

Appendix B. Complete pedon descriptions were recorded at the most representative locations as determined by the Soil Scientist, and selected sites were sampled for series representation.

2.3 Sample Collection

A total of 20 soil samples were collected from nine pedon locations for laboratory analyses.

These samples were selected in the field to be representative of soils in the area and to determine if the sampled horizon was acceptable as a borrow material. Selected soil samples

Tetra Tech December 2, 2010 3 were generally collected from pedons where the soil type was a dominant component of the map unit.

Soil samples were collected from horizons greater than three inches thick. Horizons less than three inches thick were occasionally sampled along with the most similar adjacent horizon, unless the horizon was anomalous in nature. Horizons greater than 18 inches thick were collected from the lower portion of the soil horizon.

2.4 Laboratory Analyses

Soil samples were transported under chain-of-custody protocol to Pace Analytical Laboratory

(Pace), in Billings, Montana for laboratory analysis. In general, laboratory parameters were analyzed using the methods specified by the Wyoming Department of Environmental Quality

(WDEQ) Topsoil and Overburden Guidelines (Guideline 1; WDEQ, 2004). Twenty soil samples were analyzed to include some or all of the following parameters:

Textural class (sand, silt, clay percentages) pH (acidity/alkalinity)

Calcium (Ca), Manganese (Mg) and sodium (Na)

Specific conductance (SC)

Sodium adsorption ratio (SAR)

Arsenic (As) , cadmium (Cd), copper (Cu), lead (Pb) and zinc (Zn).

The methods used for laboratory analyses are presented on the laboratory report included in

Appendix C. Field estimates for physical soil conditions are documented on the logs in

Appendix B.

2.5 Soil Borrow Map Unit Development

Preliminary map unit boundaries were identified in the field where supported by available data and site inspection. Boundaries of preliminary map units were further refined based on the results of pedon descriptions and development of conceptual map units. Many of the conceptual map units were documented in the field for further refinement based on review of all available information, including laboratory results and final pedon classifications.

Following completion of the field effort, color aerial photography was used to further assist in map unit refinement. These images revealed detail related to vegetation communities, saline-sodic surfaces, rock outcrop patterns and geologic parent materials. Each map unit within the project area was described by documenting soil pedons and salvage depths found in the map unit, their relative composition, and their placement relative to one another. Map units produced as part of this survey were composed primarily of similar soil complexes, with the smallest map units encompassing approximately one-half acre.

Tetra Tech December 2, 2010 4

2.6 Soil Suitability for Reclamation

Field observations and laboratory test information from soil samples were evaluated to determine relative suitability of soil as a plant growth medium. Site specific soil suitability criteria were developed by the USFS and MSE (MSE, 2010) to define and classify suitability

(Table 1). Soil profile characteristics and laboratory analyses are used to evaluate potential salvage depths for each soil type. Differences in suitability between horizons are reviewed to determine which soils are suitable topsoil or cover material.

The suitability criteria for cover soil presented in Table 1 are similar to criteria used for similar sites in the western US. However, due to the various potential metal toxicity issues the acidic pH number was elevated from an often used criterion of 5.5 to 6.5 (WDEQ, 2004). Soils with a pH of greater than 6.0 would also likely produce acceptable results. Therefore we have used an acceptance criterion of 6.0 assuming the soil horizon is less than a few inches thick and higher pH soil is also likely going to be utilized. However, due to the significant potential for metals toxicity at this site we recommend additional research and data collection, specifically into selenium and boron levels on-site.

For the purposes of this investigation it was anticipated only six inches of stripped topsoil would be needed to be replaced on the borrow locations. This replaced material would all be the topsoil, or A horizon, and the total depth of salvage to unsuitable borrow material was considered in determining the total salvage depth of each unit. We recommend 12 inches of borrow be placed on the reclamation sites.

3.0 EXISTING SOIL MAPPING

3.1 Bluff A

NRCS soil mapping (USFS, 2010; Appendix A) for Bluff A identified three main soil map units along with the Dumps, mine (Du), map unit. The three main map units are the Cohagen-Rock outcrop–Cabba variant complex (CrF), three to 100 percent slopes along the benches and side slopes, and the Cohagen fine sandy loam (CoE), 15 to 50 percent slopes in the drainages and lower slopes. The Werner-Watrous loams (WeC), two to nine percent slopes were located above the former mine site. These Soil Series are generally loamy-textured shallow soils.

The Cohagen and Cabba soils are generally shallow, loamy soils with weathered bedrock at depths of less than 20 inches below ground surface (bgs). The A horizons are generally two to seven inches thick. The Werner and Watrous loams are more developed soils, most often with

A and B horizons to bedrock. The Cohagen series is most often over weathered sandstones also at seven to 20 inches while the Watrous loam is moderately deep to bedrock (20-40 inches) and well developed. The Watrous Series would provide suitable borrow locations.

Tetra Tech December 2, 2010 5

3.2 Bluff I

The soil investigation area for Bluff I primarily contained two separate National Cooperative Soil

Survey (NCSS) soil map unit designations (USFS, 2010; Appendix A). Within this area, two primary map units were encountered: the Cohagen fine sandy loam (CoE), 15 to 50 percent slopes at the upper two thirds of the drainage, and the Parchin-Bullock fine sandy loams (PbB), two to nine percent slopes.

As discussed above, the Cohagen and Cabba soils are generally shallow loamy soils with weathered bedrock at depths of less than 20 inches bgs. The A horizons are generally two to seven inches thick. The Parchin consists of moderately deep, well-drained soils formed in residuum weathered from sandy and loamy sedimentary rocks. The depth to weathered soft-bedded sandstone bedrock is typically 25 to 30 inches but ranges from 20 to 40 inches. The

Bullock series consists of moderately deep loamy soils on residuum weathered from soft sandstone or silty or clayey shales interbedded with soft sandstone. These soils have both sandy clay loam and clay loam subsoils and have SARs up to 20 which exceeds suitability criteria for a borrow material (Table 2).

4.0 SOIL PROFILE RESULTS

4.1 Bluff A

Two areas were presented as potential borrow locations (Figure 2). One soil pit was advanced in Potential Borrow Area 1 (A9210-13; Figure 2). Based on soil physical and chemical characteristics (Tables 2 and 3), this area appears adequate to provide some borrow materials.

However, the extremely limited areal extent of this area and pockets of fine sandy loam soil textures within the soil profile, which are subject to increased soil erosion, will require additional borrow materials for reclamation in this area. Assuming six inches of topsoil could be removed from the area (A_5, Figure 3), less than 200 cubic yards of soil is available from this site.

Potential Borrow Area 2 (Figure 2) was also investigated but found unsuitable as a source of borrow due primarily to shallow soils with excessive coarse fragment size and content. Soil profile A9210-12 (Figure 2) was excavated near this proposed borrow source. No suitable borrow was observed at this location or along the entire south edge of Bluff A primarily due to coarse fragment size and volume or due to very shallow soils over bedrock.

Several gently sloping benches were investigated along the north access road (Figure 3).

However, while some salvage is available on these benches, the soil profiles are shallow to bedrock with sandy surface textures A9210-14 (Appendix B; Figure 3). Evidence of past disturbance can also be observed in this area which has lead to significant localized water erosion. Weathered bedrock was encountered at a depth of 16 inches bgs in soil profile A9210-

14 (Appendix B). Erosional cuts in this area indicated some slightly deeper soils (Watrous

Series, Appendix A) on bench. Therefore, approximately six inches appears to be available from these bench areas assuming erosion control measures are immediately taken following

Tetra Tech December 2, 2010 6 borrow operations. Assuming a six-inch borrow depth, approximately 1,800 cubic yards of borrow material may be available here (Table 3). We would recommend additional investigation of these benches for documentation of depths prior to finalizing reclamation plans.

Soil profile A9210-15 (Appendix B) was also excavated at the upper end of the Lone Tree

Spring drainage (Figure 3). This area was also determined to be less than 12 inches to soft bedrock making this area inappropriate as a borrow source.

Much of the former erosion around Bluff A appears to have stabilized considerably since previous disturbance. Disturbance of these shallow sandy soils has the potential to create increased erosion from this area. Additionally, due to the shallow nature of these soils there will be insufficient existing soil remaining to maintain a 12 to 18 inch depth of soil at the borrow locations which may be acceptable if aggressive revegetation and sediment control measures are taken.

4.2 Bluff I

The potential borrow area located north of Bluff I is characterized as a gently sloping shallow drainage bounded by moderately to steeply sloping side hills (Figure 4). Two borrow areas had been proposed for Bluff I (Figure 4). General soil characteristics included stratified alluvial parent material in the center of the valley and colluvium and residuum-derived soils on the side slopes.

A total of 17 soil pits were excavated in the proposed borrow areas north of Bluff I (Figure 5). Up to 80,000 cubic yards may be available for borrow in this area (Table 3). However, limiting factors included sodic soils in the alluvial-controlled areas in the center of the shallow drainage and at the lower (north) end of the drainage and depth to bedrock, and steep slopes along the east and west margins of the site (Table 2; Figure 5). Active erosion was observed at the south end of the area below Bluff I and deposition of these materials is occurring near the north end of the area. Soil textures are generally clay loams with 20 to 40 percent clay. However, sandy-textured soils were also observed. Sandy soils were often observed to be associated with sodic conditions. Laboratory data indicate SARs tend to be elevated in this area, often due in part to low calcium and manganese concentrations. Should additional borrow materials be required, these sodic soils have a potential for reclamation success using gypsum amendments.

This drainage has the potential to provide borrow material to cap and revegitate re-worked spoils in the formerly mined area I. However, care should be taken not to remove soils in the center of the drainage due to elevated SARs. Areas adjacent to the shallow drainage bottom were observed to have potential borrow up to 40 inches thick. Based on the USFS requirement for organic matter, compost or some other organic materials will need to be incorporated into the growth media. Additionally, disturbance and removal of a vegetative cover at the south end of this drainage will have the potential for creating additional saline-sodic conditions at lower elevations at the north end of the drainage due to increased subsurface soil water movement creating additional areas of saline seep.

Tetra Tech December 2, 2010 7

5.0 LABORATORY ANALYTICAL RESULTS

The results of the physical and chemical laboratory analyses from this investigation and the previous investigation conducted by MSE (MSE, 2010) are presented in Table 2. The following sections summarize the results of laboratory analyses and present interpretations relative to reclamation planning.

5.1 Soil Physical Properties

Soil textures in the project area are predominately clay loams with some sandy clay loams and sandy loams. Of the soil samples collected, clay content ranged from between six and 46 percent with an average of 20 percent. These soils throughout the survey area have potential for use in reclamation due to their low clay content. However, the sandy soils have low water-holding capacity which limits re-growth potential and promotes susceptibility to wind and water erosion.

5.2 Soil Acidity and Alkalinity

The acidity and alkalinity of soils in the project area are closely tied to parent materials and topographic position. The pH of samples tested ranged from between 5.9 to 9.3, and averaged

7.3 (neutral pH = 7). Five soil samples were slightly acidic with pH levels of 5.9 to 6.4.

However, these samples were all collected from thin surface soil horizons. At all locations, the soil samples collected directly below the surface horizon had a pH in excess of 6.6.

Two soil samples exceeded the alkalinity limit of 8.5. Both samples were collect by MSE at depths greater than three feet bgs. The sample (BP-3-97, Table 2) with the highest pH of 9.3 also had a SAR of 22.4 which indicates soil at this depth (36 to 72 inches bgs) is not suitable for borrow. Soil samples (9110-11, Table 2) collected within ten feet of this profile at depths of less than one foot and less than 20 inches had pH’s of 6.2 and 7.0, respectively. The other sample

(BP-1-95, Table 2) with a pH in excess of 8.5 was sampled at a depth of 36 to 48 inches bgs indicating borrow in this area should be limited to a depth of less than 36 inches.

Based on this information, we do not believe it is necessary to restrict any soil from this location for potential borrow due to acidic conditions. The alkaline soils were associated with sodic conditions and therefore not suitable as a borrow source. These soils were located in the center of the drainage.

5.3 Specific Conductance (SC)

A soil’s SC (often referred to as electrical conductivity or EC) is a measure of the salt content of the soil recorded in millimhos per centimeter (mmhos/cm) and is directly related to osmotic potentials and soil water availability. Soils with an SC less than 8.0 mmhos/cm are generally considered non-limiting. The USFS borrow restriction value was given as 6.0 mmhos/cm. Of the soils sampled in the project area, two soil samples (I9210-18, 11-21” and I9210-17, 0-7”) exceeded the USFS threshold value of 6.0 mmhos/cm. Along with elevated SC concentrations, Tetra Tech December 2, 2010 8 the SAR concentrations also exceeded the threshold indicating these soils are not adequate for borrow purposes. Sample I9210-17, 0-7” is considered saline and sodic based on the laboratory results.

The remainder of the samples had acceptable SC values. The average SC value was 2.0 mmhos/cm and therefore SC is not a notable limiting factor in most of the project area.

However, due to the elevated saline conditions observed in lower elevations of this drainage, removal of vegetation at the higher elevations has the potential to increase saline conditions at lower elevations since more soil water may be made available to transport salts through the subsoil profile.

5.4 Sodium Adsorption Ratio (SAR)

The SAR of the soil is an indicator of soil sodicity, which degrades soil structure and inhibits plant growth at higher levels. Levels above 8.0 can be limiting and may cause surface crusting.

Levels above 12.0 are further limiting and may require amendment treatments to re-vegetate.

The average SAR of soils sampled was less than seven which indicates numerous soil samples did contain SARs above the desired concentration. This indicates sodium concentrations are a concern at this site. However, SAR and total sodium concentrations out of the main drainage path and above a depth of approximately three feet were generally well below threshold value.

5.5 Metals

Soil samples were analyzed for arsenic, cadmium, copper, lead and zinc concentrations as part of this investigation. While elevated metals concentrations were occasionally observed, none of the samples exceeded the USFS threshold values and are not expected to limit regrowth.

5.6 Nutrient Content

The nutrient content of native soils was not analyzed as part of this investigation. However, organic matter content was generally observed to be low with depth in many of the soil profiles.

Soil organic matter (OM) is a critical source of nutrients in native soils and often accounts for free nutrient levels. Additionally, it is anticipated that borrow may be removed to a depth of up to three feet bgs which is most often very low in OM. Addition of OM through compost is recommended. Similar to OM content, phosphorus, nitrate, and potassium concentrations are expected to be low with depth but adequate and should not be limiting factors to re-growth potential.

6.0 SOIL SALVAGE CONCLUSIONS AND RECOMMENDATIONS

Soil salvage at the Riley Pass Mining Area will be affected by the topsoil physical and chemical characteristics, physiographic position on the landscape, and equipment available for salvage.

The topsoil horizons exhibit more loamy textures, fewer coarse fragments, higher organic matter content, and higher nutrient concentrations. These soils can be expected to promote vegetative growth, hydrologic function, long-term nutrient cycling, and erosional stability in the reclaimed

Tetra Tech December 2, 2010 9 landscape relative to deeper materials. The topsoil warrants segregated salvage and storage where conditions permit.

To determine potential borrow depths, each of the soil pedon descriptions was reviewed to determine the optimum and maximum salvage depth at each location. These depths were then used to identify the observed range and average salvage depth for each of the soils in the project area (Figure 5). The general site specific soil suitability criteria developed by the USFS to define and classify suitability (Table 1) appear appropriate. In Tetra Techs opinion the pH restriction of 6.5 could be lowered slightly but should not be allowed below 6.0. The SC and

SAR restrictions appear appropriate. However, we recommend additional research and data collection, specifically into selenium and boron levels on-site

The need for salvage to the maximum depth of available material will depend on the reclamation plan and the suitability of re-graded spoil in the re-graded landscapes. As such, the recommended depths may not be appropriate where more or less soil replacement is required to reclaim disturbances. It is recommended that the top six inches be handled separately and replaced on salvage areas to promote the quickest revegetation of these newly disturbed locations. This will help minimize potential saline and/or sodic impacts at lower elevations from the borrow source areas. We recommend 12 inches of borrow be placed on the reclamation sites.

6.1 Bluff A

Although limited analytical testing was conducted in the Bluff A study area, no restrictive laboratory analyses were noted in these soils. However, the predominance of shallow soils and thin A horizon thicknesses severely limits potential salvage in this area. Several erosional cuts were also observed along the benches, which the vegetation appeared to be stabilizing.

Assuming salvage operations were to be conducted on the benches along the north road of

Bluff A, approximately 2,000 cubic yards of soil could be salvaged if six inches of topsoil is maintained on these benches. Deeper pockets may occur along the benches and could be taken advantaged of.

6.2 Bluff I

The primary chemical property limiting salvage in the Bluff I study area was observed to be elevated sodium concentrations versus other cation concentrations as measured by a soil SAR.

These sodic soils are also occasionally saline, severely limiting them as potential borrow areas.

However, soil profiles excavated north of Bluff I indicated borrow materials are available along the east and west margins of the study area. Generally, borrow depths of up to 30 inches are available along these gently sloping areas. Assuming the top six inches of soil is stripped and either temporarily stored and replaced, or direct-hauled to adjacent salvage areas, a total salvage volume of approximately 80,000 cubic yards appears to be available.

Tetra Tech December 2, 2010 10

7.0 REFERENCES

MSE, 2010. Riley Pass Removal Action Borrow Soil Test Trenching and Sampling, Sioux

Ranger District. March 24.

Tetra Tech, 2010. Riley Pass Removal Action Borrow Soil Characterization, Bluffs A and I, Plan of Study. August.

USDA. 1993. Soil Survey Manual. Handbook Number 18. Soil Conservation Service. U.S.

Government Printing Office. Washington, D.C.

2002. Field Book for Sampling and Describing Soils. Version 2.0. National Soil Survey

Center, NRCS. September, 2002.

2003. National Soil Survey Handbook: Title 430-VI. Soil Survey Staff, Natural Resources

Conservation Service (NRCS).

2010. Soil Survey of Harding County, South Dakota.

http://websoilsurvey.nrcs.usda.gov/app/WebSoilSurvey.aspx

USFS. 2010. Statement Of Work, Riley Pass Removal Action Borrow Soil Characterization, Bluff A and Bluff I Sioux Ranger District, Custer NF, Harding County, SD. July 4.

WDEQ. 2004. Guideline 1: Topsoil and Overburden. Wyoming Department of Land Quality

Division. August.

FIGURES

Bluff I Survey Area

Bluff A Survey Area

October 2010 Figure 1Survey Area Locations

Riley Pass Removal Action Borrow Soil Characterization, Bluff A and Bluff I

G:

\Bi llin gs

\R ile yP as s\A rcM ap \Fi gu re1

_B as eM ap

.m xd

³ 0 1

Miles

Custer National Forest, Harding County, South Dakota

Legend ! Soil Profile Locations

Survey Areas

Potential Borrow Area 1

Potential Borrow Area 2

A9210-14

A9210-15

A9210-13

A9210-12

October 2010 Figure 2

Bluff A, Previously Proposed Borrow Areas Riley Pass Removal Action Borrow Soil Characterization

G :\B ill in gs \R ile yP as s\

A rc

M ap

\F ig ur e2

.m xd

0 500

Feet

Custer National Forest, Harding County, South Dakota

Legend

Soil Profile Locations

Potential Borrow Areas

10 ft contours

12"

12"

12"

12"

12"

A_1

A_2

A_5

A_4A_3

A9210-14

A9210-15

A9210-13

A9210-12

October 2010 Figure 3

Bluff A Soil Profile Locations Riley Pass Removal Action Borrow Soil Characterization

G :\E nv iro nm en ta l\C or ey

\R ile yP as s\ A rc M ap _9

.3 \F ig ur e3 .m xd

0 500

Feet

Custer National Forest, Harding County, South Dakota

Legend

12" Acceptable Soil Borrow Depth

10 ft contours

Potential Borrow SiteA_4 Soil Profile Locations

9110-1 9110-29110-3

9110-4

9110-5

9110-6

9110-9

9110-8 9110-7

9110-11

9110-10

I9210-18

I9210-17

I9210-16

BP-3-97

BP-2-96

BP-1-95

October 2010 Figure 4

Bluff I Previously Proposed Borrow Area Riley Pass Removal Action Borrow Soil Characterization

G :\E nv iro nm en ta l\C or ey

\R ile yP as s\ A rc M ap _9

.3 \F ig ur e4 .m xd

0 500

Feet

Custer National Forest, Harding County, South Dakota

Legend

Soil Profile Locations

Tetra Tech - w/ lab data

Tetra Tech - w/out lab data

MSE - w/ lab data

MSE - w/out lab data

10 ft contours

Proposed Borrow Areas

18.1 Acres

3.8 Acres

9110-1 9110-29110-3

9110-4

9110-5

9110-6

9110-9

9110-8 9110-7

9110-11

9110-10

I9210-18

I9210-17

I9210-16

BP-3-97

BP-2-96

BP-1-95

I_1

I_4

I_5

I_7

I_2

I_6

I_8

I_3

30"

30"

30"

24"

12"

18"

20"

20"

October 2010 Figure 5

Bluff I, Soil Profile Locations Riley Pass Removal Action Borrow Soil Characterization

G :\E nv iro nm en ta l\C or ey

\R ile yP as s\ A rc M ap _9

.3 \F ig ur e5 .m xd

0 500

Feet

Custer National Forest, Harding County, South Dakota

Legend

Soil Profile Locations Tetra Tech - w/ lab data

Tetra Tech - w/out lab data

MSE - w/ lab data

MSE - w/out lab data

Potential Soil Borrow Areas - Maximum Borrow Depth

10 ft contours

TABLES

Table 1 Preliminary Topsoil Suitability Criteria – Riley Pass Mining Area

Property Suitable Unsuitable

Depth (cover depth) 12-18 inches <12 inches

USDA Texture (thickest layer 0-40 in.) SL >45% Clay content and LS, S

Rock Fragments (by volume) <45 (all fragments less than six inches diameter) >45

Depth to High Water Table (feet) --- Perennial wetness

Soil Acidity (pH 0-40 inches) 6.5 to 8.5 <6.5 to >8.5

Arsenic <142 ppm >142 ppm

Cadmium < 4 ppm > 4 ppm

Copper < 100 ppm > 100 ppm

Lead < 100 ppm >100 ppm

Zinc < 250 ppm >250 ppm

SAR <12 >12

Specific conductance (entire depth of cover soil) <6 dS/m >6 dS/m

Legend: Depth of growth media above bedrock or unsuitable soils USDA = US Department of Agriculture SL = Sandy Loam, LS = Loamy sand, S = Sand, C = Clay PPM = Parts per million 1 decisiemens per meter (dS/m) = 1 millimhos per centimeter (mmho/cm)

N:\TYPING\ENV-FAC\550424\Riley Pass 2010 Soils\Table 1 Preliminary Topsoil Suitability Criteria.doc 1 of 1

SAMPLE ID LAB ID

Sample Interval (inches)

Texture pH

SC

(mmhos/cm) Ca

(meq/L) Mg

(meq/L) Na

(meq/L) SAR As

Cd (mg/Kg)

Cu (mg/Kg)

Pb (mg/Kg)

Zn (mg/Kg)

NA 6.5-8.5 4-6 NA NA NA 12 142 4 100 100 250

10137359001 0-9 Sandy Clay Loam 7.2 0.7 3.3 2.8 1.4 0.8 30.4 0.9 8.5 9.8 33.8

10137359002 9-18 Sandy Clay Loam 7.8 0.97 1.5 1.1 8.6 7.5 13.5 0.75 10.1 10.2 38.8

10137359003 0-5 Clay Loam 7.1 1.3 1.6 1.0 9.3 8.0 48.4 1.2 9.8 12.6 47.3 10137359004 5-11 Clay Loam 7.5 5.0 6.2 8.7 38.1 14.0 55.5 1.3 9.5 13.2 52.7 10137359005 11-21 Clay Loam 7.4 10.5 18.4 39.3 85.0 15.8 78.9 1.8 11.8 13.5 51.6

I9210-17 10137359006 0-7 Clay Loam 6.2 11.4 20.9 32.0 102.0 19.8 34.6 0.97 14.1 15.4 56.0

I9210-16 10137359007 3-17 Clay Loam 8.0 4.7 6.7 12.5 33.3 10.7 43.8 1.1 12.6 12.6 53.50

10137359008 0-12 Sandy Loam 6.2 0.30 1.1 0.76 0.81 0.84 36.7 0.82 4.8 9.5 36.30 10137359009 12-20 Sandy Loam 7.0 0.31 1.3 0.71 1.1 1.1 15.6 0.35 7.7 13.7 57.90

9110-08 10137359010 24-36 Sandy Clay Loam 8.4 0.58 0.78 1.8 3.5 3.3 123 2.7 10.7 11.7 40.2

10137359011 0-11 Clay Loam 6.4 0.39 0.74 0.40 2.7 3.6 22.0 0.67 10.4 11.5 48.7 10137359012 24-31 Sandy Clay Loam 6.8 0.27 0.62 0.32J 1.8 2.6 22.0 0.56 8.1 8.8 35.2

10137359013 0-7 Clay Loam 6.2 0.56 0.98 0.56 4.2 4.8 28.4 0.86 13.2 14.6 51.5 10137359014 7-18 Clay Loam 6.6 0.47 0.78 0.45 3.5 4.5 30.5 0.82 10 10.7 41.1 10137359015 18-26 Clay Loam 7.2 0.61 1.2 0.88 3.8 0.75J 65.0 1.5 14.6 15.6 51.2 10137359016 26-36 Sandy Clay Loam 7.9 0.51 0.74 0.54 4.2 5.2 77.9 1.6 11.8 13.7 42.5

10137359017 36-48 Sandy Clay Loam 8.9 1.2 0.69 0.97 10.3 11.2 35.4 0.8 7.2 8.0 31.0

10137359018 0-5 Clay 5.9 0.63 1.4 0.83 4.0 3.7 40.7 1.2 15.8 17.5 67.2

10137359019 5-11 Sandy Clay Loam 6.6 0.45 0.83 0.43 3.2 4.0 107 2.2 12.8 9.6 31.7

10137359020 30-40 Clay 7.1 0.75 2.0 1.3 4.4 3.4 36.9 1.1 17.5 14.6 58.5

BP-1-95 C09110280-001 36-72 Sandy Loam 8.3 0.32 0.52 0.93 1.84 2.16 17.90 NA 8.6 NA NA

BP-3-97 C09110280-002 36-72 Loam 9.3 1.72 0.4 0.8 16.0 22.4 132.0 NA 11.3 NA NA

7.3 2.0 3.3 4.9 15.6 6.8 49.8 1.2 11.0 12.3 46.3

Legend:

Sample Interval = Given in inches below ground surface mmhos/cm = Millimhos per centimeter Pb = Lead meq/L = milliequivalents per liter (saturated paste extract) Zn = Zinc mg/Kg = milligrams per kilogram (dry basis)

Cd = Cadmium Cu = Copper

9110-02

A9210-13

9110-11

I9210-18

Table 2: Soil Chemistry

Suitability Criteria

9110-06

9110-03

Averages

Mg = Manganese in milliequivalents per liter Na = Sodium in milliequivalents per liter

Sample ID = Samples collected by Tetra Tech. Samples BP-1-95 and BP-3-97 collected by MSE (MSE, 2007)

SAR = Sodium Adsorption Ratio pH = given in standard units SC = Specific conductance (Electrical Conductivity) given in mmhos per centimeter (dS/m ; deciSiemens per meter) corrected for 25 degrees Centigrade Ca = Calcium in milliequivalents per liter

N:\TYPING\ENV-FAC\550424\Riley Pass 2010 Soils\Table 2 Soils Chemistry.xls 1 of 1

Area Total Depth

(inches) Total Depth

(minus 0.5 feet) Acres Square feet

Volume (sq_ft) (Depth*Area in sq_ft)

Volume (cubic yards)

A_1 12 0.5 0.91 39,508 19,754 732 A_2 12 0.5 0.48 20,978 10,489 388 A_3 12 0.5 0.30 12,966 6,483 240 A_4 12 0.5 0.62 27,082 13,541 502 A_5 12 0.5 0.24 10,464 5,232 194 I_1 30 2.0 11.45 498,933 997,867 36,958 I_2 12 0.5 1.50 65,469 32,735 1,212 I_3 20 1.2 0.48 21,035 25,242 935 I_4 30 2.0 6.96 303,310 606,621 22,467 I_5 30 2.0 3.35 145,978 291,956 10,813 I_6 18 1.0 1.33 57,915 57,915 2,145 I_7 24 1.5 1.54 67,072 100,609 3,726 I_8 20 1.2 1.10 47,869 57,443 2,128

Total Borrow Area A 2,056 cubic yards Total Borrow Area B 80,385 cubic yards

Area: See Figure 5 Total Depth: Assumes top six inches not used except for replacement at borrow site.

Table 3: Borrow Soil Volume Estimate

N:\TYPING\ENV-FAC\550424\Riley Pass 2010 Soils\Table 3 Borrow Soil Volume Estimate.xlsx 1 of 1

APPENDIX A

SOIL MAP UNIT AND SERIES DESCRIPTIONS

APPENDIX B

SOIL PROFILE DESCRIPTIONS

APPENDIX C

LABORATORY ANALYTICAL REPORT

October 05, 2010

LIMS USE: FR - JEFFREY RICE

LIMS OBJECT ID: 10137359

10137359 Project:

Pace Project No.:

RE:

Jeffrey Rice Tetra Tech, Inc.

PO Box 30615 Billings, MT 59107

Riley Pass 114-550424

Dear Jeffrey Rice:

Enclosed are the analytical results for sample(s) received by the laboratory on September 03, 2010.

The results relate only to the samples included in this report.

REVISED - On Sept. 22, 2010 additional analysis was requested for total metals. The metals analysis is reported herein.

If you have any questions concerning this report, please feel free to contact me.

Sincerely, Denise Jensen denise.jensen@pacelabs.com Project Manager

Enclosures

REPORT OF LABORATORY ANALYSIS

This report shall not be reproduced, except in full, without the written consent of Pace Analytical Services, Inc..

Pace Analytical Services, Inc.

602 S 25th Street

Billings, MT 591014549

(406)254-7226

CERTIFICATIONS

Pace Project No.:

Project:

10137359 Riley Pass 114-550424

Minnesota Certification IDs 1700 Elm Street SE Suite 200, Minneapolis, MN 55414 Alaska Certification #: UST-078 Alaska Certification #MN00064 Arizona Certification #: AZ-0014 Arkansas Certification #: 88-0680 California Certification #: 01155CA EPA Region 8 Certification #: Pace Florida/NELAP Certification #: E87605 Georgia Certification #: 959 Idaho Certification #: MN00064 Illinois Certification #: 200011 Iowa Certification #: 368 Kansas Certification #: E-10167 Louisiana Certification #: 03086 Louisiana Certification #: LA080009 Maine Certification #: 2007029 Maryland Certification #: 322 Michigan DEQ Certification #: 9909 Minnesota Certification #: 027-053-137 Mississippi Certification #: Pace

Montana Certification #: MT CERT0092 Nebraska Certification #: Pace Nevada Certification #: MN_00064 New Jersey Certification #: MN-002 New Mexico Certification #: Pace New York Certification #: 11647 North Carolina Certification #: 530 North Dakota Certification #: R-036 North Dakota Certification #: R-036A Ohio VAP Certification #: CL101 Oklahoma Certification #: D9921 Oklahoma Certification #: 9507 Oregon Certification #: MN200001 Pennsylvania Certification #: 68-00563 Puerto Rico Certification Tennessee Certification #: 02818 Texas Certification #: T104704192 Washington Certification #: C754 Wisconsin Certification #: 999407970

Montana Certification IDs 602 South 25th Street, Billings, MT 59101 EPA Region 8 Certification #: 8TMS-Q Idaho Certification #: MT00012

Montana Certification #: MT CERT0040 NVLAP Certification #: 101292-0

REPORT OF LABORATORY ANALYSIS

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Pace Analytical Services, Inc.

602 S 25th Street

Billings, MT 591014549

SAMPLE SUMMARY

Project:

10137359 Riley Pass 114-550424

Lab ID Sample ID Matrix Date Collected Date Received

10137359001 A9210-13, 0-9" Solid 09/02/10 00:00 09/03/10 15:15

10137359002 A9210-13, 9-18'' Solid 09/02/10 00:00 09/03/10 15:15

10137359003 A9210-18, 0-5'' Solid 09/02/10 00:00 09/03/10 15:15

10137359004 A9210-18, 5-11'' Solid 09/02/10 00:00 09/03/10 15:15

10137359005 A9210-18, 11-21'' Solid 09/02/10 00:00 09/03/10 15:15

10137359006 A9210-17, 0-7'' Solid 09/02/10 00:00 09/03/10 15:15

10137359007 A9210-16, 3-17'' Solid 09/02/10 00:00 09/03/10 15:15

10137359008 9110-11, 0-12'' Solid 09/01/10 00:00 09/03/10 15:15

10137359009 9110-11, 12-20'' Solid 09/01/10 00:00 09/03/10 15:15

10137359010 9110-08, 24-36'' Solid 09/01/10 00:00 09/03/10 15:15

10137359011 9110-06, 0-11'' Solid 09/01/10 00:00 09/03/10 15:15

10137359012 9110-06, 24-31'' Solid 09/01/10 00:00 09/03/10 15:15

10137359013 9110-03, 0-7'' Solid 09/03/10 15:15

10137359014 9110-03, 7-18'' Solid 09/03/10 15:15

10137359015 9110-03, 18-26'' Solid 09/03/10 15:15

10137359016 9110-03, 26-36'' Solid 09/03/10 15:15

10137359017 9110-03, 36-48'' Solid 09/03/10 15:15

10137359018 9110-02, 0-5'' Solid 09/03/10 15:15

10137359019 9110-02, 5-11'' Solid 09/03/10 15:15

10137359020 9110-02, 30-40'' Solid 09/03/10 15:15

REPORT OF LABORATORY ANALYSIS

This report shall not be reproduced, except in full, without the written consent of Pace Analytical Services, Inc..

Pace Analytical Services, Inc.

602 S 25th Street

Billings, MT 591014549

SAMPLE ANALYTE COUNT

Project:

10137359 Riley Pass 114-550424

Lab ID Sample ID Method Analytes Reported LaboratoryAnalysts

10137359001 A9210-13, 0-9" EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

10137359002 A9210-13, 9-18'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

10137359003 A9210-18, 0-5'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

10137359004 A9210-18, 5-11'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

10137359005 A9210-18, 11-21'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

10137359006 A9210-17, 0-7'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

10137359007 A9210-16, 3-17'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

10137359008 9110-11, 0-12'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

REPORT OF LABORATORY ANALYSIS

This report shall not be reproduced, except in full, without the written consent of Pace Analytical Services, Inc..

Pace Analytical Services, Inc.

602 S 25th Street

Billings, MT 591014549

Project:

10137359 Riley Pass 114-550424

Lab ID Sample ID Method Analytes Reported LaboratoryAnalysts

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

10137359009 9110-11, 12-20'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

10137359010 9110-08, 24-36'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

10137359011 9110-06, 0-11'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

10137359012 9110-06, 24-31'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

10137359013 9110-03, 0-7'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

10137359014 9110-03, 7-18'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

10137359015 9110-03, 18-26'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

REPORT OF LABORATORY ANALYSIS

This report shall not be reproduced, except in full, without the written consent of Pace Analytical Services, Inc..

Pace Analytical Services, Inc.

602 S 25th Street

Billings, MT 591014549

Project:

10137359 Riley Pass 114-550424

Lab ID Sample ID Method Analytes Reported LaboratoryAnalysts

ASA 10-3.3 1 PASI-MTSC1

10137359016 9110-03, 26-36'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

10137359017 9110-03, 36-48'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

10137359018 9110-02, 0-5'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

10137359019 9110-02, 5-11'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

10137359020 9110-02, 30-40'' EPA 6010 5 PASI-MIP

EPA 6010 4 PASI-MIP

USDA 21A 1 PASI-MTSC1

ASA 15-5 mod 4 PASI-MTEJS

ASA 10-3.3 1 PASI-MTSC1

REPORT OF LABORATORY ANALYSIS

This report shall not be reproduced, except in full, without the written consent of Pace Analytical Services, Inc..

Pace Analytical Services, Inc.

602 S 25th Street

Billings, MT 591014549

PROJECT NARRATIVE

Project:

10137359 Riley Pass 114-550424

Method:

Client: Tetra Tech, Inc. - MT

EPA 6010

Date: October 05, 2010

Description: 6010 MET ICP

General Information:

20 samples were analyzed for EPA 6010. All samples were received in acceptable condition with any exceptions noted below.

Hold Time:

The samples were analyzed within the method required hold times with any exceptions noted below.

Sample Preparation:

The samples were prepared in accordance with EPA 3050 with any exceptions noted below.

Initial Calibrations (including MS Tune as applicable):

All criteria were within method requirements with any exceptions noted below.

Continuing Calibration:

All criteria were within method requirements with any exceptions noted below.

Method Blank:

All analytes were below the report limit in the method blank with any exceptions noted below.

Laboratory Control Spike:

All laboratory control spike compounds were within QC limits with any exceptions noted below.

Matrix Spikes:

All percent recoveries and relative percent differences (RPDs) were within acceptance criteria with any exceptions noted below.

QC Batch: MPRP/22512 A matrix spike and matrix spike duplicate (MS/MSD) were performed on the following sample(s): 10137359001,10137359020

M1: Matrix spike recovery exceeded QC limits. Batch accepted based on laboratory control sample (LCS) recovery.

• MS (Lab ID: 859678)

• Arsenic

• Cadmium

• Lead

• Zinc

Duplicate Sample:

All duplicate sample results were within method acceptance criteria with any exceptions noted below.

Additional Comments:

Analyte Comments:

QC Batch: MPRP/22512

• 9110-02, 0-5'' (Lab ID: 10137359018)

• Zinc

REPORT OF LABORATORY ANALYSIS

This report shall not be reproduced, except in full, without the written consent of Pace Analytical Services, Inc..

Pace Analytical Services, Inc.

602 S 25th Street

Billings, MT 591014549

Project:

10137359 Riley Pass 114-550424

Method:

Client: Tetra Tech, Inc. - MT

EPA 6010

Date: October 05, 2010

Description: 6010 MET ICP

Analyte Comments:

QC Batch: MPRP/22512

• 9110-02, 30-40'' (Lab ID: 10137359020)

• Zinc

• 9110-02, 5-11'' (Lab ID: 10137359019)

• Zinc

• 9110-03, 0-7'' (Lab ID: 10137359013)

• Zinc

• 9110-03, 18-26'' (Lab ID: 10137359015)

• Zinc

• 9110-03, 26-36'' (Lab ID: 10137359016)

• Zinc

• 9110-03, 36-48'' (Lab ID: 10137359017)

• Zinc

• 9110-03, 7-18'' (Lab ID: 10137359014)

• Zinc

• 9110-06, 0-11'' (Lab ID: 10137359011)

• Zinc

• 9110-06, 24-31'' (Lab ID: 10137359012)

• Zinc

• 9110-08, 24-36'' (Lab ID: 10137359010)

• Zinc

• 9110-11, 0-12'' (Lab ID: 10137359008)

• Zinc

• 9110-11, 12-20'' (Lab ID: 10137359009)

• Zinc

• A9210-13, 0-9" (Lab ID: 10137359001)

• Zinc

• A9210-13, 9-18'' (Lab ID: 10137359002)

• Zinc

• A9210-16, 3-17'' (Lab ID: 10137359007)

• Zinc

• A9210-17, 0-7'' (Lab ID: 10137359006)

• Zinc

• A9210-18, 0-5'' (Lab ID: 10137359003)

• Zinc

• A9210-18, 11-21'' (Lab ID: 10137359005)

• Zinc

• A9210-18, 5-11'' (Lab ID: 10137359004)

• Zinc

REPORT OF LABORATORY ANALYSIS

This report shall not be reproduced, except in full, without the written consent of Pace Analytical Services, Inc..

Pace Analytical Services, Inc.

602 S 25th Street

Billings, MT 591014549

Project:

10137359 Riley Pass 114-550424

Method:

Client: Tetra Tech, Inc. - MT

EPA 6010

Date: October 05, 2010

Description: Sodium Adsorption Ratio, ICP

General Information:

20 samples were analyzed for EPA 6010. All samples were received in acceptable condition with any exceptions noted below.

Hold Time:

The samples were analyzed within the method required hold times with any exceptions noted below.

Initial Calibrations (including MS Tune as applicable):

All criteria were within method requirements with any exceptions noted below.

Continuing Calibration:

All criteria were within method requirements with any exceptions noted below.

Method Blank:

All analytes were below the report limit in the method blank with any exceptions noted below.

Laboratory Control Spike:

All laboratory control spike compounds were within QC limits with any exceptions noted below.

Matrix Spikes:

All percent recoveries and relative percent differences (RPDs) were within acceptance criteria with any exceptions noted below.

Duplicate Sample:

All duplicate sample results were within method acceptance criteria with any exceptions noted below.

Additional Comments:

REPORT OF LABORATORY ANALYSIS

This report shall not be reproduced, except in full, without the written consent of Pace Analytical Services, Inc..

Pace Analytical Services, Inc.

602 S 25th Street

Billings, MT 591014549

Project:

10137359 Riley Pass 114-550424

Method:

Client: Tetra Tech, Inc. - MT

USDA 21A

Date: October 05, 2010

Description: USDA 21A pH

General Information:

20 samples were analyzed for USDA 21A. All samples were received in acceptable condition with any exceptions noted below.

Hold Time:

The samples were analyzed within the method required hold times with any exceptions noted below.

Initial Calibrations (including MS Tune as applicable):

All criteria were within method requirements with any exceptions noted below.

Continuing Calibration:

All criteria were within method requirements with any exceptions noted below.

Internal Standards:

All internal standards were within QC limits with any exceptions noted below.

Surrogates:

All surrogates were within QC limits with any exceptions noted below.

Method Blank:

All analytes were below the report limit in the method blank with any exceptions noted below.

Laboratory Control Spike:

All laboratory control spike compounds were within QC limits with any exceptions noted below.

Matrix Spikes:

All percent recoveries and relative percent differences (RPDs) were within acceptance criteria with any exceptions noted below.

Duplicate Sample:

All duplicate sample results were within method acceptance criteria with any exceptions noted below.

Additional Comments:

REPORT OF LABORATORY ANALYSIS

This report shall not be reproduced, except in full, without the written consent of Pace Analytical Services, Inc..

Pace Analytical Services, Inc.

602 S 25th Street

Billings, MT 591014549

Project:

10137359 Riley Pass 114-550424

Method:

Client: Tetra Tech, Inc. - MT

ASA 15-5 mod

Date: October 05, 2010

Description: PSA Percent Sand,Silt,Clay

General Information:

20 samples were analyzed for ASA 15-5 mod. All samples were received in acceptable condition with any exceptions noted below.

Hold Time:

The samples were analyzed within the method required hold times with any exceptions noted below.

Initial Calibrations (including MS Tune as applicable):

All criteria were within method requirements with any exceptions noted below.

Continuing Calibration:

All criteria were within method requirements with any exceptions noted below.

Internal Standards:

All internal standards were within QC limits with any exceptions noted below.

Surrogates:

All surrogates were within QC limits with any exceptions noted below.

Method Blank:

All analytes were below the report limit in the method blank with any exceptions noted below.

Laboratory Control Spike:

All laboratory control spike compounds were within QC limits with any exceptions noted below.

Matrix Spikes:

All percent recoveries and relative percent differences (RPDs) were within acceptance criteria with any exceptions noted below.

Duplicate Sample:

All duplicate sample results were within…