Data_Gap_Assessment_Statement_of_Work_-_finalv2.pdf

Assessment and Remedial Activities Regarding Petroleum and Herbicide Impacts to Trust Resources of the Shoshone-Paiute Tribes of the Duck Valley Indian Reservation

Table of Contents

I. INTRODUCTION

II. BACKGROUND

A. Site Description

B. Heating Oil Line, Injection Well, and Petroleum Storage Tanks

C. Herbicides

D. 1995 Administrative Order

III. STATEMENT OF WORK

A. Work Objectives

B. Work Requirements

C. Work Specifications

Task 1: Project Coordination and Communication

Task 2: Project Scheduling and Organization

Task 3: Records Review

Task 4: Data Gap Analysis

Task 4a: Petroleum Releases from the Heating Oil Line and Storage Tanks

Task 4b: Hydrogeology

Task 4c: Releases from the Use and Storage of Herbicides

Task 4d: Impacts Associated with the Application of Herbicides

Task 5: Initial Site Visit and Project Planning Meeting

Task 6: Preliminary Field Work

Task 6a: Field Work Plan

Task 6b: Groundwater Monitoring

Task 6c: Assessment of the School Grounds

Task 6d: Vapor Intrusion

Task 6e: Assessment of Canals, Depositional Areas, and Roadways

Task 7: Project Work Plan

Task 8: Field Work and Data Gap Analysis Report

Task 8a: Soil Sampling – Petroleum Releases

Task 8b: Soil Gas Sampling – Petroleum Releases

Task 8c: Soil Sampling – Herbicide Releases

Task 8d: Surface Water, Soil, and Sediment Sampling – Herbicide Applications

Task 8e: Groundwater Assessment and Monitoring Well Installation

Task 9: Elevation Surveys

Task 10: Groundwater Monitoring and Testing

Task 10a: Groundwater Monitoring

Task 10b: Slug Testing

Task 10c: Aquifer Pump Testing

Task 11: Groundwater Assessment Reporting

Task 12: Remedial Action Plan

Task 13: Remedial Implementation Work Plan

IV. DELIVERABLES

V. PERIOD OF PERFORMANCE

VI. PLACE OF PERFORMANCE

VII. OPTIONAL WORK

VIII. NOTICE TO BIDDERS

IX. LIST OF ATTACHMENTS

I. INTRODUCTION

Trust resource assessment and remedial planning activities associated with the releases of petroleum and herbicides are planned within the community of Owyhee, Nevada, and on lands near irrigation canals and roadways (see Figure 1). Work entails records review, project management and planning to include coordination, presentations and meetings with the Bureau of Indian Affairs (BIA), the Shoshone-Paiute Tribes of the Duck Valley Indian

Reservation (Tribes), and the Environmental Protection Agency (EPA). Work includes soil, soil gas, surface water, and groundwater sample collection and analysis, data and information analysis and interpretation, groundwater monitoring and well elevation surveying, slug testing, aquifer pump testing, monitoring well installation, and possible monitoring well abandonment or repair, reporting of assessment activities and results through the development of drawings and tables, remedial alternative analyses, remedial design, and remedial implementation planning. Deliverables include work plans, a data gap analysis report, a remedial action plan to include the analysis of remedial alternatives, and a remedial implementation work plan.

The selected contractor will be the subject matter expert for the BIA and will provide technical support to the BIA to advance effective analyses and solutions to develop plans to resolve environmental conditions. All field work and deliverables will be reviewed, monitored, and/or approved by participating federal and tribal stakeholders to include the

BIA, Tribes, and the EPA. Travel to Owyhee, Nevada and vicinity is required for the performance of field investigations and in person meeting attendance to present project planning and technical information to stakeholders during the 510-day assessment and remedial planning period of performance.

The contractor shall schedule, coordinate, and communicate all field work with Tribal personnel, as needed, and the Division of Environmental, Safety, and Cultural Resources

Management (DESCRM), Western Regional Office, BIA.

II. BACKGROUND

A. Site Description

The town of Owyhee, Nevada is located 97 miles north of Elko, Nevada and 97 miles south of Mountain Home, Idaho, and is located just south of the Idaho-Nevada border on Nevada

State Highway 225, which turns into Idaho State Highway 51 at the Idaho-Nevada state line.

The town of Owyhee is situated at an approximate elevation of 5,400 feet above mean sea level (amsl). The land to the east rises sharply to an elevation of approximately 6,700 feet amsl. Duck Valley is on the Snake River Drainage, just north of the Great Basin. Irrigation water is controlled by the Wild Horse Dam located approximately 30 miles upstream (to the southwest) on the Owyhee River.

Groundwater occurs in a shallow alluvial aquifer. The depth to groundwater recorded in monitoring wells between 2005 and 2019 ranged from approximately 3 feet to 21 feet below ground surface (bgs). The direction of groundwater flow in Owyhee, Nevada historically has been westerly to northerly, but generally to the northwest at a gradient range between 0.003 and 0.006 feet per foot (ft/ft). The direction of groundwater flow in the vicinity of the former

Indian Health Service (IHS) hospital facility has historically been to the west; however, the hydraulic gradient is steeper in this area at 0.05 ft/ft.

B. Heating Oil Line, Injection Well, and Petroleum Storage Tanks

In February 1985, 8,000 gallons of heating oil were delivered to a 16,000-gallon aboveground storage tank (AST), located approximately 75 feet east of Highway 225. Five days later and before the 8,000 gallons should have been consumed, the tank was empty, suggesting that the pipelines that carried fuel to consumers had substantial leaks. Use of the heating oil pipeline was discontinued in 1985, and the 16,000-gallon AST continued to be used to store fuel, which was transferred by truck to individual ASTs. The location of the former 16,000-gallon heating oil storage tank is shown on Figure 2.

From September 1987 through March 1988, users of the Owyhee public water system reported a strong oil smell in the water. In March 1988, nine test pit excavations to depths

12 to 15 feet below the ground surface (bgs) were conducted at locations to the east, west and north of the Tribal maintenance building. Free-phase hydrocarbons (FPH) were observed on the groundwater surface in two test pits located north of the Tribal maintenance building. Soil was excavated along the buried pipeline north of the Tribal maintenance building to groundwater, and FPH were encountered beneath pipeline fittings. Soil samples obtained from underneath the pipeline contained concentrations of total petroleum hydrocarbons (TPH) in the diesel range (TPH-d) from 11,000 to 12,000 milligrams per kilogram (mg/kg). See page 189 of the Subsurface Investigation Report, SECOR, May 2000 attachment.

Additionally, in March 1988, the 12,000-gallon diesel underground storage tank (UST) located on the east side of the former Roads maintenance building was removed (see

Figure 2). No leakage or petroleum contamination of soils was observed. Soils tests were purportedly conducted, but no data was found. Also, in March 1988, a 12,000-gallon diesel

UST located south of the former power plant (east of the highway) was removed (see Figure

2). No leakage or petroleum contamination of soils was observed. Apparently, soil sampling was not conducted.

Also, in May 1989, a 2000-gallon UST adjacent to the old BIA office, currently the Tribal

Resources building was removed. In July 1990, a 1500-gallon diesel UST at the BIA Law

Enforcement building, Building 305, was removed.

Sometime during 1989, a former 1,000-gallon AST containing gasoline located at the northeast corner of the Roads maintenance yard was vandalized. It was estimated that between 200 to 800 gallons of gasoline were released to the ground surface.

During the installation of a water line in November 1995, approximately sixty feet of pipeline was removed northeast of the Tribal maintenance building near the intersection of Gah-Nee

Road and BIA Road. Soils in the vicinity of the heating oil line were reported to be impacted with heating oil. See page 332 of the Subsurface Investigation Report, SECOR, May 2000 attachment.

In June 1995, the EPA Region 9, pursuant to the Safe Drinking Water Act (SDWA), issued an Administrative Order (Order) to BIA. Among other findings in the Order, EPA found that the sump or drain in the Roads maintenance building led to a shallow injection well allowing spills and drainage from the interior of the building to reach subsurface soils and the shallow groundwater table. The EPA directed BIA to immediately cease use of the injection well and assess and abandon the well. Following that Order, the sump or drain in the Roads maintenance building was plugged or sealed preventing any further drainage from the interior of the building to reach the injection well.

Roads Shop Facility Work Plan, Bureau of Reclamation, October 1998

In response to the Order, the Bureau of Reclamation assisted BIA with the development of a

Work Plan to facilitate removal of impacted soils, the removal of pipelines and drains, the sampling and analysis of soil and groundwater, characterization of contaminant impacts in soil and groundwater, and groundwater monitoring.

Subsurface Investigation Report, SECOR, May 2000

In 1999, BIA removed most of the remaining heating oil pipeline and significant quantities of petroleum contaminated soils, where feasible. The heating oil line locations under streets and Highway 225 were integrity tested but not removed. PCS under streets and Highway

225 were not removed and PCS near utilities and under structures were not removed.

Associated with the removal of the heating oil line BIA also conducted a subsurface investigation to estimate the remaining heating oil impacts to soil and groundwater and characterized the hydrogeology of the site. The results from this investigation and the previous investigation conducted in April 1998 suggest that four major releases (Locations 1 through 4, below) and two moderate releases (Locations 5 and 6, below) of petroleum products had occurred. Their locations were:

(1) Along the heating oil pipeline east of Highway 225;

(2) At a former heating oil UST, located southeast of Building 310, 200 feet west of

Highway 225;

(3) At a 90-degree turn in the pipeline, 475 feet west of Highway 225 at the intersection of Gah-Nee Road and BIA Road;

(4) Along the pipeline near the ASTs located in the northeast corner of the Tribal maintenance yard;

(5) At a former UST location at the Law Enforcement building, Building 305; and

(6) At the discharge pipe outlet west of the BIA Roads maintenance building.

Of these releases, four of them (Locations 2 through 5) have impacted groundwater.

Evidence of groundwater impact in these four areas consisted mainly of TPH-d, although groundwater down-gradient from the ASTs located in the Tribal maintenance yard release location (Location 4) contained both TPH-d and total petroleum hydrocarbons in the gasoline range (TPH-g). Groundwater was not encountered during excavation at Location

1, and the rocky subsurface prohibited water sample collection; it is therefore not known whether groundwater in this area was impacted. Groundwater samples collected in the area surrounding the discharge pipe outlet at the injection well (Location 6) indicated that groundwater was not impacted.

Numerous other areas where petroleum releases occurred along the pipeline, at former storage tank locations, and along the Roads maintenance building drain line and injection well were investigated in 1999 and mitigated through soil removal. Relatively shallow subsurface soils that were impacted with petroleum products by past activities (e.g., equipment storage) at the former Roads maintenance yard were also excavated and removed. In total, approximately 2,850 cubic yards (yd3) of impacted soil were removed from throughout the site. Of the nearly 30 areas excavated during this investigation, TPH contaminated soil was left in 18 of the areas due to the location of buildings or structures, roads or utilities prevented further excavation, or where the amount of clean soils overlying impacted areas made the removal of the soils cost prohibitive.

See pages 60 through 79, 332, 361 and 364 of the Subsurface Investigation Report, SECOR, May 2000 attachment for figures showing site features and contaminated soil removal areas to include the heating oil alignments.

Groundwater Impact Assessment of former BIA Road Shop on Owyhee Drinking Water

Wells, SRK Consulting, May 2001

In 2000, BIA advanced and sampled 21 soil borings, 18 of which were converted to groundwater monitoring wells (MW-1 through MW-18). See Figure 2 for monitoring well locations. The analytical data from samples collected during the installation of the wells provided further evidence that soils and groundwater in the areas delineated in 1999 were impacted with TPH. During the November 2000 sampling event, groundwater samples from the wells were analyzed for TPH-g, volatile organic compound (VOCs), semi-volatile organic compounds (SVOCs) and the eight metals identified by the Resource Conservation and

Recovery Act (RCRA) as hazardous (arsenic, barium, cadmium, chromium, lead, mercury, selenium, and silver).

The VOC and SVOC analyses provided an indication of the concentration of degraded TPH-d components and solvent constituents in the groundwater but did not provide TPH-d concentrations. No metal concentrations were detected in the groundwater samples and all

VOC concentrations reported were below the Federal primary drinking water standards.

Samples from MW-5 were also analyzed for pesticides and herbicides because of possible historic improper disposal of these compounds to the injection well in the vicinity of the former drinking water wells, Well #1 and Well #2. No pesticides or herbicides were detected in MW-5.

BIA also removed two USTs and one AST from the former IHS Hospital site. Only non-native backfill soils were removed from the UST basin, and soil samples collected from native soils in the excavation had TPH-d concentrations ranging from 560 mg/kg to 6,100 mg/kg. Three monitoring wells were installed in the vicinity of the hospital (MW-16, MW-17, and MW-18). Low concentrations of naphthalene, a degradation product of TPH-d, were detected in each of the three wells.

Report of Findings from Soil Excavation and Groundwater Monitoring, SECOR, December

In 2002, the BIA removed and replaced roads in Owyhee, Nevada. While the roads were removed, BIA removed PCS from beneath the roads where these soils had been previously inaccessible during PCS removal in 1999. Approximately 1,932 yd3 of PCS were excavated from beneath roads. The total volume of soils excavated was comprised of 1,348 yds3 from the area near the intersection of Gah-Nee Road and BIA Road; 560 yd3 from the area along the pipeline near the ASTs in the northeast corner of the Tribal maintenance yard; and 24 yds3 from approximately 50 feet west of Highway 51 along the northern edge of Justice

Road. Approximate locations of the 1999 and 2002 excavations are found in the two reports, Subsurface Investigation Report, SECOR, May 2000 and Report of Findings from

Soil Excavation and Groundwater Monitoring, SECOR, December 2002.

Associated with the 2002 excavation of PCS, the extent of PCS that had not been excavated during the 1999 and 2002 excavations was estimated. PCS not excavated remain in the ground in areas west of Gah-Nee Road west of Building 312, under and north of College Way north of the Tribal maintenance yard, southeast of Building 310, along utility corridors, and throughout the soil/water interface (capillary fringe). Soil in the vicinity of well

MW-10 on the east and west sides of Highway 225 is impacted with TPH-d.

Emergency Order Issued to the Bureau of Indian Affairs, SECOR, July 2005

In a letter dated July 21, 2005, from SECOR to the EPA, SECOR documented assessment and remedial efforts performed associated with the removal of the Roads maintenance building drain line and injection well indicating that the groundwater was not impacted above detection limits of the analyses, approximately 50 cubic yd3 of impacted soils was over excavated and removed from the area of the discharge outlet at the injection well, and impacted soils along the drainage line were over excavated to successfully remove the contamination.

Summary Report, Well Installation, Abandonment and Monitoring Activities, October 2007 to

May 2009, December 2009

From September 2004 and June 2005, BIA monitored and sampled 17 monitoring wells for four quarters. The June 2005 analytical data indicated that groundwater in the area encompassing wells MW-6, MW-8, MW-11, and MW-13 continued to have TPH-g concentrations ranging from 0.54 to 2.0 milligrams per liter (mg/L) and TPH-d concentrations from 1.3 to 67 mg/L. TCE was first detected in monitoring well MW-10 during the

September 2002 sampling event. The observed TCE concentration has remained relatively stable, ranging from 1.2 to1.6 micrograms per liter (µg/L) over the entire period of groundwater monitoring.

Based on the 2004 and 2005 groundwater monitoring events, in 2007, BIA received a contractor proposal recommending that groundwater sampling be continued, and additional soil borings and monitoring wells be installed to further delineate the extent of TPH impacts to soils and groundwater

During August and September 2008, BIA abandoned five monitoring wells (MW-4, MW-5, MW-16, MW-17, and MW-18) since data collected over numerous sampling events has shown that these wells are not impacted. Also, during this period, three municipal wells

(Well #1, Well #2, and Well #3) were abandoned, and 13 monitoring wells (MW-5R, and

MW-19 through MW-30) were installed. These new and existing wells were monitored quarterly for a year. See Figure 5 for well locations. Samples were analyzed for TPH-g, TPH-d, benzene, toluene, ethylbenzene, and total xylenes (BTEX), and naphthalene.

Additionally, the sample collected from well MW-10 was analyzed for trichloroethylene

(TCE).

Associated with the results of the work conducted between August and September 2008, in

2009, the contractor recommended that remedial objectives for the site be established, including threshold remedial action goals for criteria contaminants, followed by the development and implementation of a Remedial Work Plan and continued monitoring to evaluate the effectiveness of remedial activities.

Groundwater Assessment, Groundwater Contaminant Characterization and Groundwater

Monitoring, DSE, November 2013

In April 2013, a groundwater monitoring event occurred involving the sampling and analyzing of groundwater from each of the existing monitoring wells. Samples were collected from a total of twenty-three (23) monitoring wells and reported that areas of groundwater contamination were relatively localized (TPH-d being the exception), and that only benzene, was detected above the Regional Screening Level (RSL) in MW-24. Each sample was analyzed for BTEX, TCE, Dinoseb, gasoline and diesel range organics.

Dinoseb and TCE was not detected in any of the samples.

Groundwater Assessment Report, Akana, August 2021

In 2021, a Groundwater Assessment Report was completed summarizing the recent delineation of the extent of petroleum hydrocarbon impacts to shallow groundwater at the site. The report findings indicate that groundwater containing petroleum hydrocarbons at concentrations exceeding EPA health-based standards continues to persist beneath two areas at the site, termed by the contractor, the “East and West Groundwater Areas”. In these areas, residual concentrations of petroleum hydrocarbons in subsurface soil within the vadose and groundwater fluctuation zones continue to dissolve in groundwater. Three new wells, MW-31, MW-32, and MW-33 were installed. Locations of the wells are shown on

Figure 2.

Analytical results for constituents in groundwater are summarized in these three reports, Summary Report, Well Installation, Abandonment and Monitoring Activities, October 2007 to

May 2009, December 2009, Groundwater Assessment, Groundwater Contaminant

Characterization and Groundwater Monitoring, DSE, November 2013, and Groundwater

Assessment Report, Akana, August 2021.

C. Herbicides

During 1995 and 1996, BIA:

• Removed and disposed of several 55-gallon drums containing used motor oil, roads sealant, herbicides (2,4-D, 2,4,5-T, and Dinoseb) from the Roads maintenance yard.

• Through an interagency agreement with EPA, approximately 40 cubic yards of

Dinoseb contaminated soil located in a dirt floor shed were removed. Soils were excavated to a depth of seven feet bgs.

In managing the assessments of the Roads maintenance yard and the former location of the

Irrigation Warehouse , BIA had looked at this information from the perspective of these properties as industrial use. Initially, it was thought that these properties were Agency reserve land, but it was later found out to be leased land.

In June 1999, during this excavation of PCS in the storage bays in the Roads maintenance yard (Yard), a yellow material, Dinoseb was discovered. The work involving the excavation of PCS in the yard is found in the Subsurface Investigation Report, SECOR, May 2000.

The initial work conducted regarding the discovery of Dinoseb involved preparing the work plan, Site Characterization Work Plan, SECOR, July 1999. This plan involved describing air monitoring, the rationale for work to include soil sampling and analyses, and the strategy to characterize the Yard. After the development of this work plan, two investigations were conducted: Phase One, Site Characterization Report, SECOR, November 1999, and Phase

Two, Site Characterization Report, Herbicide Contamination, SECOR, February 2000.

After the demolition of the Roads maintenance building and storage bays, an investigation occurred of the drain line underneath the former location of the building. Additional herbicide investigative work was conducted as well. This work resulted in the report, Additional Road Shop Soil Investigation, SECOR, November 2004.

In 2004, after the demolition of the Irrigation Shop, herbicide investigative work occurred at the former location of this building. This work resulted in the report, Irrigation Shop Soil

Investigation, SECOR, January 2005.

Regarding the historic use of 2,4-D and 2,4,5-T, in February 2024, a review of the report, Phase I Environmental Site Assessment, Former Irrigation Shop and Former

Hospital, Pezonella Associates, Inc., 1997 indicated the following information found on Page

10: "According to Mr. [Jim] Smith, the only chemicals he can recall using as an employee there were the herbicides 2,4-D more recently, and possibly 2,4,5-T more than 20 years ago. These chemicals were used to kill foliage that grows in the irrigation canals. Due to the amount of irrigation canals, any one spot would get an application of herbicide every three years”

The mixture of 2,4-D and 2,4,5-T is commonly referred to as "Agent Orange". Use of 2,4,5-

T has been banned due to the evidence of health problems exhibited by people who used larger amounts of the herbicide. The historic uses of 2,4-D and 2,4,5-T was thought to only have been used for weed control along roadsides since facilities management staff had communicated this anecdotal information.

Associated with the data gap assessment work awarded to Akana, Akana recommended additional work as found in the work plan, Supplemental Soil Sampling Work Plan, Akana, December 2016. This work was implemented and resulted in the report, Supplemental Soil

Pesticide Investigation Report, Akana, July 2019.

D. 1995 Administrative Order

In the Order, EPA directed BIA to implement corrective actions. These actions were included among other requirements stipulated by the Order and summarized below:

➢ Locating all piping and drains associated with injection well

➢ Sampling fluids within the disposal well and piping

➢ Permanently plugging the disposal well and associated drains

➢ Proper storage or disposal of contents of drums

➢ Removal and disposal of all standing pools of contaminants and stained soil

➢ Proper storage or disposal of contents of drums

➢ Develop work plan for remediation of impacted soil and groundwater if necessary

In a letter dated May 2, 2018, from EPA to the BIA, EPA found that BIA had satisfied the requirements of the Order and terminated the Order based on the completion of the Order requirements and the analytical results of groundwater source sampling from the Owyhee

Public Water System (Owyhee PWS) including:

• Verification that BIA permanently ceased the injection or disposal of waste fluids at the former Roads maintenance building in 1995.

• Verification that BIA provided sufficient documentation in 2005 that releases to the disposal/injection well were characterized and remediated and that these releases did not impact groundwater.

• Analytical results of monitoring the System below SDWA Maximum Contaminant

Levels (MCLs) for the contaminants that resulted in EPA’s issuance of the Order in

1995.

• BIA’s completion of multiple environmental investigations and removal actions since

1995, including assessment and remedial activities as provided in a letter from BIA to

EPA, dated September 29, 2016.

• Through coordination with the Tribes, BIA confirmed that there were not any privately or publicly operated drinking water wells or any plans for any new public water system wells in Owyhee, Nevada.

• BIA would continue to monitor groundwater to determine the effectiveness of natural attenuation of any remaining residual contaminants in Owyhee, Nevada.

III. STATEMENT OF WORK

A. Work Objectives

The overall objective of this statement of work (SOW) is the performance/conduct of contracted services, support, and products necessary to assess and remediate identified contamination to eliminate contaminant exposures and risks using cleanup goals developed through coordination with the Tribes and EPA. Activities and objectives include:

• Assessment and remedial activities necessary to assess and perform remedial planning associated with petroleum (heating oil, diesel, gasoline, and trichloroethylene) contamination to subsurface soils and shallow groundwater

• Assessment and remedial activities necessary to assess and provide remedial planning for herbicide (2,4-D, 2,4,5-T, and Dinoseb) contamination to surface soils at the former Roads maintenance yard and Irrigation Warehouse locations, along irrigation canal banks and associated depositional areas, and along roadways.

B. Work Requirements

The contractor will perform technical services and support, subcontracted as necessary, to implement and fully execute Tasks 1 through 13. Services and support are to include but are not limited to project management and coordination; furnishing of personnel, labor, equipment, materials and supplies necessary for the performance of work and the development and completion of acceptable deliverables.

All necessary permits or approvals will be obtained prior to implementation of field work.

Permitting and planning requirements include access agreements, archaeological stakeholder approval, and environmental compliance requirements. No work shall commence without approval from applicable regulatory agencies and stakeholders.

The contractor will be required to comply with all environmental regulations associated with the work outlined in this SOW. The contractor shall adhere to applicable federal, Tribal, and state requirements. Application and procurement of permits and licenses and payment of fees are the responsibility of the contractor.

This requirement includes a total of thirteen tasks as listed below.

PHASE I: Project Planning

- Task 1: Project Coordination and Communication

- Task 2: Project Scheduling and Organization

- Task 3: Records Review

- Task 4: Data Gap Analysis

- Task 5: Initial Site Visit and Project Planning Meeting

- Task 6: Preliminary Field Work

- Task 7: Project Work Plan

PHASE II: Field Investigations and Assessment Reporting

- Task 8: Field Work and Data Gap Analysis Report

- Task 9: Elevation Surveys

- Task 10: Groundwater Monitoring and Testing

- Task 11: Groundwater Assessment Reporting

Phase III: Remedial Planning

- Task 12: Remedial Action Plan

- Task 13: Remedial Implementation Work Plan

C. Work Specifications

Task 1: Project Coordination and Communication

Although meetings are planned to be virtual, the contractor will need to conduct site visits and interact with Tribal and BIA personnel as necessary to plan and implement the tasks in this SOW.

The contractor shall include coordination and communication costs including, but not limited to, nine virtual meetings and three on-site meetings with notes and summaries, meeting preparation and presentations; project status calls, emails, and travel as part of the management costs to complete the requirements in this SOW. Associated with this task, the contractor shall propose and develop the technical approach and project team representation to facilitate communication and coordination. Since the composition and caliber of the project team and support staff will vary among proposals, project team meeting organization and attendance will be critical in evaluating the contractor’s approach to the work and the costs bid for this task. This task shall also include staffing (e.g. GIS, environmental technicians, engineers, etc.) to support the project team. The contractor will be required to utilize Microsoft Teams as their virtual platform for these virtual meetings.

The contractor shall include costs for travel and coordination to support the following nine virtual and three on-site meetings with site reviews:

• Presentation of the draft Field Work Plan (virtual)

• One on-site planning meeting to include presentation of the draft Project Work Plan and on-site review of field conditions, and preliminary groundwater monitoring

• Presentation of final Project Work Plan (virtual)

• One on-site meeting to present the results of the field work, and the draft Data Gap

Analysis Report

• Presentation of the draft analysis of alternatives (virtual)

• One on-site meeting to present the draft Remedial Action Plan

• Presentation of the final Remedial Acton Plan (virtual)

• Presentation of the draft Remedial Implementation Work Plan (virtual)

• Presentation of the final Remedial Implementation Work Plan (virtual)

• Three additional virtual meetings as determined

Task 2: Project Scheduling and Organization

The contractor shall prepare the project schedule to communicate project milestones for completion of the work. The schedule shall include SOW task completion timelines and provide scheduling to plan and implement the work. Associated with the performance of this work, the contractor will need to update as circumstances merit. This task includes management of the project schedule for the duration of the project. The contractor shall submit the project schedule within thirty (30) calendar days of the Notice to Proceed (NTP) date.

The contractor shall prepare their project organization to include contractor and subcontractor staffing. Key federal and suggested contractor project personnel are provided in Table 1 below. The contractor’s proposal will establish the roles and responsibilities of key contractor personnel. Contractor staffing disciplines may differ from the conceptual staffing included in this SOW. The contractor should consider that the project schedule will need to be adjusted through the project. Any changes or adjustments to the schedule associated with the optional work will be a part of the costs associated with the applicable optional work/modification.

Table1: Key Federal and Contractor Project Personnel

Name Organization/Title/Role Telephone

Number Address Email Address

John F. Krause

BIA/ Program

Manager/Contracting Officer’s

Representative

(602) 240-8446 2600 N Central Avenue

Phoenix, AZ 85004 John.Krause@bia.gov

Melanie Schiaveto BIA/Contracting Officer (602) 88811 2600 N Central Avenue

Phoenix, AZ 85004

Melanie.Schiaveto@bia.gov

Lydia Dorrance EPA Region 9/ Project Manager (415) 972-3461

75 Hawthorne Street

San Francisco, CA

94105

Dorrance.Lydia@epa.gov

Marissa Snapp Shoshone-Paiute

Tribes/Environmental Manager

(208) 759-3100 Owyhee, Nevada Marissa.Snapp@shopai.org

TBD Contractor, Project Manager

TBD Contractor, Field Manager

TBD

Contractor, Field

Technician/Geologist

TBD Contractor, GIS/CAD/Graphics

TBD Contractor, Chemist

Task 3: Records Review

The contract shall thoroughly review all technical reports, correspondence and other documents related to the environmental assessment and remediation of soils and groundwater contamination in the community of Owyhee, Nevada. This information shall include, but not necessarily be limited to the reports and documents provided as attachments to this requirement.

The contractor shall complete this task within sixty (60) calendar days from the NTP date.

mailto:John.Krause@bia.gov mailto:Melanie.Schiaveto@bia.gov mailto:Dorrance.Lydia@epa.gov mailto:Marissa.Snapp@shopai.org

Task 4: Data Gap Analysis

Based on the document review and information assembled during Task 1, the contractor will develop a project work plan to resolve data gaps as provided in the SOW and as determined and recommended by the contractor. As applicable, the contractor will identify and incorporate as practicable, the performance and/or conduct of Phase II field investigations and Phase III cleanup or remedial plans that are necessary to complete/fulfill the requirement into the approved Project Work Plan deliverable (see Task 7). The results of this review shall be reported in the Project Work Plan and referenced as needed to support rationale for the contractor’s approach, activities, and methods proposed and memorialized in the Project Work Plan. Results of this review will also be included and incorporated into the evaluation of remedial alternatives considered during development of the Remedial

Action Plan (see Task 12).

This task involves the analysis of existing data and information to determine data needs to resolve ambiguities in the nature and extent of petroleum and pesticide releases. The overlying issue is Tribal concerns that the releases of herbicides (2,4-D, 2,4,5-T and

Dinoseb) and petroleum have caused, and/or are causing a public health threat to the Tribal community. The contractor shall establish a data gap assessment process and sampling and analysis plans to address those data gaps. In addition to soil, soil gas, water, and groundwater sampling, soil borings and groundwater monitoring wells will be introduced.

Data needs are comprised of four categories: (1) petroleum releases from the heating oil line, and storage tanks; (2) hydrogeology; (3) releases from the use and storage of herbicides; and (4) impacts associated with the application of herbicides. The contractor will evaluate these data gaps and for each data gap, develop an assessment strategy to resolve those data gaps as feasible and as best as practicable.

Task 4a: Petroleum Releases from the Heating Oil Line and Storage Tanks

Tribal concerns exist that petroleum releases have caused and/or are causing a public health threat and that the petroleum plume in the groundwater resides under the Owyhee

Combined School property.

• Delineation of the heating oil plume to determine the northern extent of the plume in the east groundwater area west of Highway 225.

• Determination of possible impacted groundwater north-northwest of the former

Power Plant.

• Determination of possible impacted groundwater at and to the north-northwest of the former Irrigation Warehouse

• Delineation of the heating oil plume to determine whether this plume impacts school property.

• Delineation of the gasoline plume to determine the source location of the plume.

• Delineation of the TCE plume to determine the source location of the plume.

• Determination of possible soil gas issues caused by petroleum releases.

• Delineation of soil vapor plume(s) associated with soil and groundwater contamination.

• Survey of private water wells.

Task 4b: Hydrogeology

Tribal concerns exist concerning the downward migration of petroleum. Associated with this concern, the contractor will evaluate the shallow aquifer stratigraphy, the nature of lateral and vertical sediment heterogeneity, the thickness and depth of higher versus lower permeability zones, pinch-outs, or other large changes in lithology or sediment facies that may influence horizontal and vertical groundwater flow directions.

This data gap analysis will be needed to support the observation that the reduction in groundwater concentrations of contaminants over time is due to natural attenuation processes and not vertical migration to other groundwater zones.

The existing aquifer information (field and literature) appears to be sufficient for a determination of shallow groundwater flow rates. Municipal wells drawing water from the deeper groundwater in the vicinity have been closed and abandoned. Municipal wells drawing water from the deeper groundwater are located at least a mile away. Consideration should be given as to whether these wells can impact the downward migration of groundwater in the community of Owyhee, Nevada. Geologic cross sections will need to be generated to understand lithology and degree of heterogeneities in the subsurface within the impacted zones.

This analysis is critical to developing a Conceptual Site Model (CSM) of the aquifer system and the distribution of contaminants in local groundwater. The CSM must include at least a general description of this system to guide an assessment of the potential effect of shallow groundwater zone contamination on the regional aquifer system.

Task 4c: Releases from the Use and Storage of Herbicides

Although the Roads maintenance yard and Irrigation Shop area were assessed for herbicides, further analysis is needed with the goal of cleaning up these sites to residential or unrestricted use rather than industrial use. The contractor shall review the information and develop a plan to further delineate for herbicides to include 2,4-D, Dinoseb, and 2,4,5-T.

Task 4d: Impacts Associated with the Application of Herbicides

The recent discovery of the apparent use of herbicides along irrigation canal banks indicates that investigation is necessary. This investigation will involve records review, if available, and employee interviews to obtain any information as to the: (1) quantities of herbicides used; (2) the extent of canals, or any other areas, including areas along roadways, where these chemicals were applied; and (3) areas that are irrigated. Since the use of toxic herbicides occurred over 40 years ago, historical information related to the use and application of toxic herbicides probably will not be available.

The contractor will develop a factual background that will affect the sampling needed. Flood irrigation was/is utilized and irrigation canals flow into reservoirs where Tribal members fish and recreate. A broad phased sampling plan is needed to encompass these depositional areas, including probable testing of receptors (e.g. crops and fish). The contractor will utilize existing mapping of the canals, develop sampling and analysis plans of the soils along the canal banks and sediment where these materials were potentially applied, sampling and analyses of the soils and sediment in depositional areas; sampling and analyses of the irrigation water and reservoir water, and sampling and analyses of receptors.

The contractor shall complete this task within ninety (90) calendar days from the NTP date.

Task 5: Initial Site Visit and Project Planning Meeting

Within one hundred fifty (150) calendar days from the NTP date, the contractor will travel to

Owyhee, Nevada to attend, facilitate and conduct a project planning meeting with federal and tribal officials and personnel to discuss the work activities and deliverables of this requirement, project logistics, and schedule. During this meeting the contractor will present to the audience a Microsoft PowerPoint presentation. The presentation will include an overview of past environmental assessment and remedial activities contracted by BIA, summary of informational and data needs to be gathered by the contractor during the performance period of this requirement, and potential future short- and long-term requirements for environmental monitoring and remediation. The contractor will present a conceptual site model during the presentation/discussion, and based on available information, identifying potential risks from contaminant releases to human health and/or natural resources.

During the meeting, the contractor will provide participants with hard copies of the Task 4

Draft Project Work Plan deliverable. The contractor shall make an estimated twelve (12) copies available to the participants attending the planning meeting. The contractor’s presentation will complement the introduction and scope and deliverables of this requirement, as outlined in the Draft Project Work Plan. The duration of the meeting shall be an estimated minimum of three (3) hours.

The contractor shall conduct a minimum six (6) hour site visit the day before the planning meeting (two to three days is anticipated for this task). Observations, notes, photographs, and other information collected during this task and documented during periodic teleconferences shall be utilized by the contractor for revision and finalization of the Project

Work Plan.

Task 6: Preliminary Field Work

To address concerns regarding environmental conditions, the contractor will immediately conduct field work to initially address these concerns and to assist in developing the Project

Work Plan. The contractor shall complete the field work within one hundred (100) calendar days from the NTP date.

Task 6a: Field Work Plan

Within forty-five (45) calendar days from the NTP date and prior to the initiation of field work, the contractor shall submit a brief (less than fifteen (15) pages) concise field work plan and a virtual presentation of the Field Work Plan. This plan is intended to ensure that the field work meets the intent of this task. Contractor protocols regarding site safety and health and sampling and analyses will be referenced.

The contractor will allow a minimum thirty (30) calendar day review and comment period following the distribution of the draft Field Work Plan at the project planning meeting. The contractor shall incorporate to the greatest extent practical, and as appropriate, any comments, concerns and/or recommendations provided. The contractor will provide one (1) hard and one (1) electronic copy of the Field Work Plan to DESCRM, the Tribes, and EPA.

The Field Work Plan deliverable shall be submitted within ninety (90) calendar days from the

NTP date.

Task 6b: Groundwater Monitoring

The last groundwater sampling of the monitoring wells at the site was completed in

December 2019. This task includes the monitoring and sampling of 29 wells.

Prior to finalization of the Project Work Plan, the contractor shall collect groundwater samples from each of the twenty-nine (29) monitoring wells to establish current contaminant concentrations in groundwater. Samples will be analyzed for VOCs by Method

8015D/gasoline range organics (GRO), SVOCs by Method 3511/8015, VOCs by Method

8260D, polynuclear aromatic hydrocarbons (PAHs) and SVOCs by Method 8310/8270E, and chlorinated herbicides by Method 8151A. Samples will be analyzed to at least a limit of

0.1 mg/l. The contractor shall collect samples from existing monitoring wells: MW-1R, MW-

2, MW-3, MW-5R, MW-6, MW-7, MW-8R, MW-9 through -15, MW-19 through -29, MW-30R, MW-31 through -33 (29 samples plus 3 duplicate samples and 3 trip blanks for a total of 35 samples).

The existing well locations and Top of Casing (TOC) elevations will be surveyed by a licensed surveyor and added to the site database. The wells will be developed prior to sampling. The sampling will be conducted using low flow sampling methodology. The sampling purge waters will be stored in 55-gallon drums and disposed of appropriately.

Task 6c: Assessment of the School Grounds

The Tribes have expressed concerns that the school grounds are contaminated. Planned groundwater work through the installation of groundwater monitoring wells will occur as a part of Task 8e. This task involves the collection of soil samples throughout the school grounds.

The proposal will assume 40 soil sample locations with the collection of soil samples near surface (3 to 6-inches). Samples will be analyzed for VOCs by Method 8015D/gasoline range organics (GRO), SVOCs by Method 3511/8015, polynuclear aromatic hydrocarbons

(PAHs) and SVOCs by Method 8310/8270E, and chlorinated herbicides by Method 8151A.

Task 6d: Vapor Intrusion

An exposure route of concern is the vapor intrusion pathway. Several factors including the shallow groundwater table, seasonally cold climate, and residential use of the impacted area indicate the potential for vapor intrusion at the site. Associated with the development of a probable vapor intrusion investigation, encompassing indoor air sampling of occupied buildings and seasonal conditions, the contractor will initially conduct soil gas studies as discussed below.

The site groundwater data indicate that petroleum hydrocarbons are present in shallow groundwater exceeding the EPA screening level concentrations for the vapor intrusion exposure pathway. To investigate whether this pathway is complete, ten samples of soil gas will be collected. These locations include two near MW-24, one downgradient of MW-24 and upgradient of Tribal Resources building, one near Well MW-8R, and one near well MW-28, and five locations at other locations to include the school grounds as determined by the contractor.

The samples will be collected following the protocols described in the EPA Office of Solid

Waste and Emergency Response (OSWER) Technical Guide for Assessing and Mitigating the Vapor Intrusion Pathway from Subsurface Vapor Sources to Indoor Air. The boreholes for sampling will be advanced using appropriate installation/drilling methodology techniques

(e.g. direct push rig or a hollow stem auger drill rig) to a depth of three ft bgs. Samples will be collected into Suma canisters supplied by an accredited analytical laboratory. Sample locations will be recorded in field notes. Soils encountered during drilling will be logged as described in Task 8a.

The collected soil gas samples will be sent to the laboratory for the following analyses: (1)

VOCs and TPH-GRO by Method TO-15; and (2) SVOCs and TPH-DRO by Method TO-13.

Task 6e: Assessment of Canals, Depositional Areas, and Roadways

Due to the apparent use of the herbicides, 2,4-D, 2,4,5-T and Dinoseb along irrigation canal banks and along roadways. The contractor will collect 70 soil and sediment samples and 20 samples of irrigation water and reservoir water. These 90 samples will be analyzed using

EPA Method 8151A. Additional duplicate and trip blank analyses will be performed as determined by the contractor. The analytical results from this effort along with the preparatory and field work will inform the development of the Project Work Plan and the

SAP as required in Task 8d.

Task 7: Project Work Plan

The contractor shall prepare and submit draft and final copies of a Project Work Plan to communicate and to formalize project objectives, approach, methods, notification procedures, schedule (Gantt chart or similar, with schedule of significant milestones), regulatory requirements, organizational structure (including list of subcontractors), and contractor and personnel licenses and certifications.

The Project Work Plan shall include, but not be limited to, the following components:

- Site description

- Identification of all current and former UST and AST systems within the study area to include storage tank systems that have not been assessed for releases or for which no data exists

- Nature and extent of contamination

- Project overview and objectives

- Figures

• Nature and extent of contamination

• Existing and proposed monitoring wells

• Former and existing storage tanks in the community of Owyhee, Nevada

• Wells within two miles of the community of Owyhee, Nevada

- Previous investigations

- Environmental setting

- Project schedule

- Summary of current conditions

- Supplemental data needs

- Scope of work for additional investigations

- Site conceptual model

- Sampling and Analysis Plan (SAP)

- Health and Safety Plan (HASP)

- Quality Assurance Project Plan (QAPP)

The contractor will allow a minimum forty-five (45) calendar day review and comment period following the distribution of the draft Project Work Plan at the project planning meeting. The contractor shall incorporate to the greatest extent practical, and as appropriate, any comments, concerns and/or recommendations provided. If any comments, concerns and/or recommendations are not incorporated, the contractor shall explain why. The contractor will provide one (1) hard and one (1) electronic copy of the Project Work Plan to DESCRM, the

Tribes, and EPA.

The Project Work Plan deliverable shall be submitted within one hundred fifty (150) calendar

Task 8: Field Work and Data Gap Analysis Report

The contractor will prepare and submit a draft and final Data Gap Analysis Report upon completion of the field work in this section and the completion of the second groundwater monitoring event and elevation survey. All Task 8 field work to include the Data Gap

Analysis Report shall be completed within two hundred forty (240) calendar days from the

NTP date.

Through the data gap analysis described in Task 4, additional field work will be necessary.

This work will be considered optional work.

Utility locating and land use approvals will be performed before drilling or the collection of soil sampling, as applicable. Investigative Derived Waste (IDW) from drilling and groundwater collection will be stored in 55-gallon steel drums for disposal and disposed of appropriately.

Task 8a: Soil Sampling – Petroleum Releases

Sampling of subsurface soils will be conducted in three areas of the site. The data will be used to estimate the location, extent, and volume of…