SOW_Hi-Yu_Mine_EECA_mh.pdf

Statement of Work

Hi-Yu Mine – Alaska

Engineering Evaluation and Cost Analysis

A. Introduction/Background

The Hi-Yu Mine (Hi-Yu) is the site of a historic gold mine in the Fairbanks area. Ore extracted from an adit in the western wall of the Moose Creek valley was processed in a stamp mill and the fine gold was amalgamated using elemental mercury. Processed tailings were pushed out of the stamp mill, into a pile next to Moose Creek. Although the claim occupied by this old mine is active, no mining activity is known to have occurred since the early 20th century.

The tailings pile has remained in place for decades without significant human disturbance. In recent years, the pile has begun to erode into a small wetland complex adjacent to Moose Creek.

Based entirely on visual inspection, it is impossible to estimate how far the tailings have migrated. The presence of processed mine tailings that are actively eroding into a wetland adjacent to a water body create environmental conditions that warrant evaluation.

Project Description

The BLM intends to perform a non-time critical removal action of the tailings pile at the Hi-Yu

Mine. The removal action shall be conducted in accordance with the processes defined under the

Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), specifically, 40 CFR 300.415. This project involves data collection and analysis that will characterize the tailings pile, and a feasibility assessment of multiple removal alternatives.

Current understanding of tailings pile characteristics is limited to the data reported in a master’s thesis discussing water concentrations in the vicinity of the tailings pile (Clark, 2005). Existing data indicate that the tailings are limited in lateral and vertical extent and contain measurable concentrations of arsenic and mercury. Recent observations of the tailings pile indicate that it is eroding, creating the potential for material enriched in arsenic and mercury to impact Moose

Creek and adjacent wetlands.

B. Scope of Work

The contractor shall develop an Engineering Evaluation/Cost Analysis (EE/CA) for a non-time critical removal action under consideration for the tailings pile located on the Hi-Yu Mine. The

EE/CA shall be performed in a manner that is consistent with Guidance on Conducting Non-

Time-Critical Removal Actions under CERCLA (EPA 540/F-93/057) and Guidance for

Conducting Treatability Studies Under CERCLA (EPA/540/R-92/071a).

B.1 Task 1 – Project Management

The project manager regularly coordinates with the BLM Contracting Officer’s Representative

(COR), participates in technical discussions with BLM Alaska State Office and Anchorage Field

Office staff, coordinates contracted project staff, provides BLM with regular progress reporting, and generates project invoices.

A project schedule shall be developed and submitted to BLM as the initial submittal under this

Scope of Work. The dates for all other draft and final submittals covered in this Scope of Work will be established in coordination with the BLM COR and documented in the project schedule.

The project schedule shall be submitted to BLM within one week of receiving authorization to proceed.

B.2 Task 2 – Fence Repair and Vehicle Removal

The BLM erected a fence prohibiting easy access to the mine claim. In recent years, the fence around the historic stamp mill has been damaged and refuse that is not related to mining has been left on the site. The contractor shall repair or replace the fence such that it is in working condition equivalent to when initially installed.

The contractor shall remove a wrecked and burned pickup truck from the tailings pile and dispose in a permitted solid waste facility. The contractor shall record the coordinates of the pickup location prior to removal, noting specific locations where plastics inside the truck have melted and dripped on to the tailings pile. The contractor shall also remove miscellaneous solid waste from the tailings pile that was left at the time the truck was burned.

B.3 Task 3 – Characterize Tailings and Surrounding Area

The contractor shall collect site specific data that will characterize the tailings pile and potentially affected surrounding area. The objectives of this task are to:

• Define the nature and extent of contamination associated with the processed tailings

• Establish the impacts of tailings migration on soil, surface water, sediment, and groundwater

• Estimate the volume of tailings and impacted soil/sediment

The contractor shall collect qualitative and quantitative data as necessary to meet the objectives listed above. Data quality objectives shall be defined in the Site Characterization Work Plan and overall data quality should support remedial decision making under CERCLA.

All sampling locations, regardless of media, shall be recorded using GPS. All characterization data shall be archived in an ESRI-compatible GIS database and site maps shall be submitted in native format with the final report (refer to Task 5 – Deliverables in this scope of work).

Surface Tailings and Soil: The contractor shall characterize surface soil and tailings in and near the tailings piles by documenting visual observation, field screening methods, and laboratory analysis. All data collection locations shall be recorded using GPS at a level of accuracy that will support mapping at a site scale.

Surface soil characteristics and concentrations shall be measured in the field using an X-ray

Fluorescence (XRF) meter. Surface soil data shall be collected at regular intervals to provide complete and even coverage of the tailings piles and surrounding area. The contactor shall establish an asymmetric grid covering the tailings pile and wetlands complex downstream of the pile, encompassing an area approximately 1200 feet by 250 feet. The grid shall coincide with the lateral extent of the area where tailings appear to be present based on satellite imagery and preliminary site reconnaissance. The grid shall have a node spacing of approximately 85 feet in the short direction and 100 feet in the long direction (52 field screening locations). It may be necessary to collect field screening data data at closer intervals at the upstream and downstream ends of the estimated tailings footprint. The contractor shall assume that an additional 20 locations for field screening may be defined at the discretion of the field team lead.

Surface soil samples shall be collected for laboratory analysis at 24 of the locations where field screening data are collected. The exact locations of the samples will be defined based on results of field screening. The laboratory samples shall reflect the full range of concentrations measured in the field and represent all areas within the grid, with emphasis on nodes on or near outer edges of the grid in order to establish the lateral extent of contamination.

Tailings within the Abandoned Truck Footprint: A pickup truck was burned and abandoned at the northern end of the tailings pile. It is anticipated that plastic material from the truck melted onto the tailings material below the truck. Three surface samples shall be collected, within the truck footprint, where melted plastic is most likely to have pooled. Three additional samples shall be collected from an approximate depth of 1 foot below each surface sample. All samples shall be submitted to a laboratory for analysis.

Subsurface Tailings and Soil: Subsurface soil samples shall be collected for laboratory analysis at 14 of the locations where field screening data are collected, plus 10 additional locations outside the estimated contaminant plume to establish background contaminant levels. The exact locations of the samples will be defined based on results of field screening and at the discretion of the field team lead. The contractor shall drill 24 soil borings to collect the subsurface samples.

Each boring shall be advanced to a depth that is approximately 1 foot below the water table. The contractor shall assume that the water table is 5 feet below the ground surface.

Subsurface soil samples shall be collected at 2.5-foot intervals from the surface to total depth of

5 feet. Each sample shall be logged and field screened using an XRF meter. One subsurface sample collected from each boring at 2.5 feet below ground surface shall be sent to an offsite laboratory for analysis (24 samples plus QA/QC samples). The other samples will be held under chain of custody under conditions that will preserve data quality as long as possible. The extra samples may be analyzed at the request of the BLM.

Groundwater Monitoring Wells: Four of the soil borings shall be completed as monitoring wells per requirements defined in the Alaska Department of Environmental Conservation, Division of Spill Prevention and Response, Contaminated Sites Program, Monitoring Well

Guidance. The monitoring wells will be constructed as follows:

• Blank pipe and screen shall be Schedule 40 PVC flush thread and extend approximately

2.5 feet above ground surface

• The screen shall be 10 feet long with 0.20 machine slot and set such that the middle of the screen is the same depth as the water table

• The bottom cap shall be Schedule 40 PVC, flush thread

• The wellhead will be constructed using a steel security casing with locking top that is set at least 2 feet below the ground surface and cemented in place

Each well shall be developed until the discharge is clear and free of sediment.

The four wells shall be placed such that water table elevations measured at all four wells will support an estimate of groundwater flow direction and gradient. The location of all four wells shall be recorded using GPS and the elevations of the top of the steel security casing, top of the

PVC casing and adjacent ground surface shall be recorded.

Groundwater Sampling: No less than 72 hours after all four wells have been fully developed, the depth to water level will be measured in each well and a groundwater sample shall be collected from each for laboratory analysis. All groundwater samples shall be analyzed for the same parameters as those specific for subsurface soils. No field screening for metals will be required for groundwater samples.

Each monitoring well shall be sampled using EPA’s low flow (minimal drawdown) water sampling procedures per EPA/540/S-95/504. The following parameters shall be monitored during sample collection and data shall be used to establish that the sample is representative of in situ conditions per standard low flow sampling methodology: total dissolved solids, pH, specific conductance and dissolved oxygen.

Table 1: Summary of Sample Analyses

Sample Type Field Screening Laboratory Analysis Comments

Surface Soil X RCRA Metals Final sample locations shall be selected in the field based on field screening data

Surface Soil/within truck footprint X

RCRA Metals, Polyaromatic

Hydrocarbons, VOCs, SVOCs

Subsurface Soil

X RCRA Metals

Samples shall be selected for laboratory analysis based on field screening data

Groundwater RCRA Metals Total Concentrations

B.4. Task 4 – Community Meeting Support

The BLM may conduct one or more public meetings to inform the public of the selected removal action approach and to seek input on that proposed action. The contractor shall develop a slide presentation in support of the public meetings. The slide presentation shall document the project objectives and findings and describes the rationale behind the selected removal action approach.

The slide presentation shall be no longer than 15 slides and include maps and graphics that illustrate the results of the site characterization and feasibility assessment documented in the

EE/CA.

The contractor shall create a one-page fact sheet that briefly summarizes historical mining activity on the Hi-Yu site and the results of this project. The contractor shall use text and graphics to convey the information in the fact sheet. The fact sheet will be distributed at public meetings organized for this project.

B.5. Optional Task 5 – Bench Scale Treatability Study

The contractor shall plan, execute, and report a bench scale treatability study of a process that complexes the mercury in the tailings to prevent leaching in water. The study shall be designed to demonstrate the feasibility of reducing mercury mobility in water under conditions similar to those at the Hi-Yu Mine. The contractor shall plan the treatability study in coordination with

Task 3 (Characterize Tailings and Surrounding Area) so that any data specific to the site or in situ tailings needed to complete the treatability study is collected as part of site characterization.

The contractor shall coordinate with the BLM in identifying a technology with demonstrated history of inhibiting mercury mobilization in water through the process generally referred to as leaching. The contractor shall design, implement and report a bench scale study that will demonstrate effectiveness in preventing mercury from mobilizing in water that is exposed to Hi-

Yu Mine tailings.

The contractor shall develop a work plan that describes the technology to be evaluated and discuss why it was selected. The plan shall also describe the methods to be used, data that will be collected and the general approach to data analysis. The contractor shall submit the work plan to

BLM and DEC for review and comment prior to beginning the bench scale study.

The contractor shall develop a report that describes the methods used for the study, emphasizing any deviations from the methods described in the work plan. The data collected as part of the study shall be summarized and results shall be reported. Data analysis and conclusions shall be discussed in sufficient detail to allow reviewers to understand the basis for conclusions. The report shall discuss the feasibility of the process evaluated through the study and recommend next steps.

C. Task 5 – Deliverables

Requirements: all schedules, plans and reports shall be submitted as required deliverables. The primary deliverables for this scope of work are:

• Project Schedule (prepared in coordination with the BLM)

• Site Characterization Work Plan

• Engineering Evaluation/Cost Analysis (EE/CA)

• Action Memorandum

• Slide presentation and fact sheet for public meetings

• Treatability Study Work Plan and Report

Draft and final versions of all deliverables shall be submitted to BLM for review and comment.

The Site Characterization Work Plan, EE/CA Report, Action Memorandum and Treatability

Study Plan and Report shall also be submitted to the Alaska Department of Environmental

Conservation (DEC) for review and comment. The contractor shall be prepared to meet with the

BLM to discuss comments on all draft documents. The revised draft document shall be submitted to the DEC for comment and BLM shall be supplied a copy of the DEC draft. The contractor shall be prepared to meet with the BLM and DEC to discuss comments on all draft documents.

The final document shall reflect resolved DEC comments. The number of draft and final hard copies listed in Table 2 reflect the number of copies to be provided to both the BLM and DEC.

Table 2: Summary of Deliverables

Deliverable Draft Final

Format

No. of Hardcopy

Format Native Format

No. of Hardcopy

Project Schedule PDF 0 PDF * 5

Site Characterization Work Plan

MS Word &

PDF

4 PDF

EE/CA Report MS Word &

PDF

4 PDF

Action Memorandum MS Word &

PDF

4 PDF

Public Meeting Slide Presentation

PowerPoint 0 PowerPoint

& PDF *

Project Fact Sheet PDF 4 PDF * 30

Treatability Study Work Plan MS Word &

PDF

4 PDF

Treatability Study Report MS Word &

PDF

4 PDF

* Native format is the format in which the text, table or figure was originally generated. Because deliverables are compiled and submitted as PDF, individual components of the final deliverable are to be submitted as part of the deliverable package.

The deliverables listed above are produced in a variety of file formats which are then compiled into a single document for submittal. All but the project schedule and presentation slides generally consist of text, tables and figures. The final version of each document shall be accompanied by separate documents in native format consisting of:

• Text in Microsoft Word 2010 format

• Tables in Microsoft Word or Excel format

• Figures in PDF or, if generated using GIS software, as shape files in ESRI compatible format

The native files shall be submitted electronically along with the final PDF document. The final versions of the schedule and slide presentation are descried below.

Project Schedule: The contractor shall develop a project schedule within 20 working days of receiving authorization to proceed. The project schedule shall be submitted to BLM as a Gantt chart in PDF.

Site Characterization Work Plan: The work plan shall describe field data collection objectives, methods, and quality assurance/quality control measures.

EE/CA Report: The contractor shall compile a report consistent in format and content with an

Engineering Evaluation/Cost analysis as described in Guidance on Conducting Non-Time-

Critical Removal Actions under CERCLA (EPA 540/F-93/057). Note that Appendix C of the referenced EPA guidance lists components of an EE/CA report.

Action Memorandum: Once the EE/CA report has been finalized, the contractor shall draft an

Action Memorandum for BLM/DEC review and comment. The Action Memorandum shall be consistent in format and content with Guidance on Conducting Non-Time-Critical Removal

Actions under CERCLA (EPA 540/F-93/057).

Public Meeting Slide Presentation and Fact Sheet: The contractor shall develop the slide presentation for public meetings using PowerPoint. The BLM will provide the contractor with a standard BLM format to be used for all slides in the presentation. The draft and final slide presentation shall be submitted to BLM in PowerPoint and PDF format along with hard copy.

The fact sheet shall be no longer than one page and summarize the current project findings and selected removal action. The fact shall convey project findings in text and color figures.

Accessible Documents: The electronic PDF version of the final EE/CA and final Action

Memorandum/Decision Document shall be in Rehabilitation Act Section 508 compliant. The

PDF shall be generated using Adobe Acrobat version 10 and in Microsoft Word version 2010 format. Section 508 requires that Federal agencies' electronic and information technology is accessible to people with disabilities to assure accessibility by the visually impaired using assistive technology such as screen readers and refreshable Braille displays. Guidance on Section

508 compliance is available at http://www.section508.gov/. In meeting this requirement, the contractor shall use the following checklist:

1. Document file name does not contain spaces or special characters.

2. Document file name should be concise, generally be limited to 20-30 characters, but make the content of the file clear in the context in which it is presented.

3. Document properties for Title, Author, Keywords, and Language are properly filled out.

4. If the edit function of Adobe Acrobat was used, all Comment and Markup items must be deleted.

5. A visual check has been done to ensure no hidden data from MSWord or other applications used to create the original document are present.

6. All images and/or non-text elements have alternative text descriptions (see Note 4 below).

7. All charts and graphs have an alternative text description and provide a description in the text immediately below the chart/graph.

8. Files of 10 pages or more have internal bookmarks.

9. Color is not used to convey important information, e.g., "See red text below."

10. Data tables identify row and column headers.

11. Layout tables do not identify row and column headers

12. Data cells in tables are associated with row and column headers.

13. All tables read from left to right and top to bottom.

14. All hyperlinks use the full Web address, e.g., http://www.blm.gov/ (not simply www.blm.gov).

15. Pages with multi-column text, tables, or call-out boxes have been checked for correct reading order using the Acrobat Professional "Read Aloud‟ function.

http://www.section508.gov/ http://www.blm.gov/ http://www.blm.gov/

16. All needed accessibility tags have been added and a full Accessibility Report has been run in Adobe Acrobat Professional 10* or higher showing no errors present.

17. A separate text-only version has been provided when there is no other way to make the content accessible. (Example: An organizational chart must have a text-only version).

Checklist Notes:

1. If content will be available as html or text, it is not required that the accompanying PDF file be Section 508 accessible.

2. A PDF created by scanning a paper document in TIFF or another image format is not 508 compliant. Either a text-only version must be provided, or, for complicated figures and maps, the ALT tag must have title and description and a point of contact person as defined in the following:

a. Map Title _____ Description ________. If you need help in using the data or information here, please contact the Alaska State Office Public Information Center at

907-271-5960.

3. Adobe provides Accessibility best practices at:

http://www.adobe.com/accessibility/best_practices.html#acrobatx

4. PDF forms require a specialized accessibility review because they present an additional degree of complexity.

5. If a graphic is purely decorative or included for spacing purposes (such as a 1 pixel gif spacer), an ALT tag is not required. If the graphic is not referenced at a specific point in the text, it is best to include it in the reading order at a convenient point, for instance, at the end of a paragraph.

Additional guidance on DOI policy for complying with Section 508 of the Rehabilitation Act can be found at: http://www.hhs.gov/web/policies/checklistpdf.html.

D. D. BLM and Other Government Points-of-Contact:

BLM Points of Contact:

• The Project Manager and Contracting Officer’s Representative is:

McKenzie Huso mhuso@blm.gov

907-474-2263

• The Contracting Officer is:

Patrick Euler peuler@blm.gov

907-271-4136 http://www.adobe.com/accessibility/best_practices.html#acrobatx http://www.hhs.gov/web/policies/checklistpdf.html

E. References

Alaska Department of Environmental Conservation, Division of Spill Prevention and Response, Contaminated Sites Program. Monitoring Well Guidance. 2013.

Clark, J. M. Chemical Variations in the Waters Draining the Hi-Yu Mine (thesis). 2005.

Harris, E., and Smith, D. Guidance for Conducting Treatability Studies Under CERCLA.

EPA/540/R-92/071a (NTIS PB93-126787), 1992.

OSWER Publication 9360.0-32. Guidance on Conducting Non-Time-Critical Removal Actions

Under CERCLA. EPA 540/F-93/057 (PB93-963402), 1993.

Puls, R., and Barcelona, M. Low-Flow (Minimal Drawdown) Ground-water Sampling

Procedures. EPA/540/S-95/504, 1996.