F10AK029804_04.10_0500_a.pdf

FT FINAL MMRP PROPOSED PLAN, OB/OD AREA (MRS-04) AND REMAINING OB/OD AREA (MRS-14), FORMER FORT GLENN, UMNAK ISLAND, ALASKA

PROPOSED PLAN

FORMER FORT GLENN, UMNAK ISLAND, ALASKA

FUDS PROJECT NUMBERS: F10AK029804 AND F10AK029814

April 2014

F10AK029804_04.10_0500_a F10AK029814_04.10_0500_a

200-1e

at the Former Fort Glenn, Umnak Island, Alaska

PUBLIC COMMENT PERIOD

May 1 through June 2, 2014

PUBLIC MEETINGS

May 6, 2014

Time: 6:30 – 7:30 p.m.

Z.J. Loussac Public Library

3600 Denali Street Anchorage, Alaska 99503

May 7, 2014 Time: 6:30 – 7:30 p.m.

Unalaska Public Library

64 Eleanor Street Unalaska, Alaska 99685

Comments on the Proposed Plan will be accepted during the public comment period. Comments or questions concerning this Proposed Plan, or the Preferred Alternative, should be addressed to:

U.S. Army Corps of Engineers - Alaska District Attn: Ms. Valerie Palmer

P.O. Box 6898 (PM-ESP-FUDS) JBER, Alaska 99506-0898

Phone: (907) 753-2578 E-mail: POA-FUDS@usace.army.mil

For more information, please visit the Information Repositories, which contain project documentation such as work plans and reports:

Library Building, Suite 111

3211 Providence Drive Anchorage, Alaska 99508

Phone: (907) 272-7547

Unalaska Public Library 64 Eleanor Street

Unalaska, Alaska 99685 Phone: (907) 581-5060

Former Fort Glenn, Umnak Island 3

TABLE OF CONTENTS

Table of Contents

1 INTRODUCTION

2 SITE BACKGROUND

3 SITE CHARACTERISTICS

4 SCOPE AND ROLE OF THE

RESPONSE ACTION

5 SUMMARY OF SITE RISKS

6 REMEDIAL ACTION OBJECTIVE

7 SUMMARY OF REMEDIAL

ALTERNATIVES

7.1 Alternative 1: No Action

7.2 Alternative 2: LUCs

7.3 Alternative 3: Focused Surface

Removal and LUCs

7.4 Alternative 4: Surface Removal and

LUCs

7.5 Alternative 5: Surface Removal, Focused Subsurface Removal, and LUCs

7.6 Alternative 6: Surface Removal, Subsurface Removal, and LUCs

7.7 Alternative 7: Surface Removal, Focused Soil Cover, and LUCs

7.8 Alternative 8: Focused Surface

Removal, Focused Subsurface Removal, and LUCs

8 EVALUATION OF ALTERNATIVES

9 PREFERRED ALTERNATIVE

10 COMMUNITY PARTICIPATION

11 REFERENCES

12 GLOSSARY OF TERMS

TABLES

List of Tables

Table 1 – Detailed Analysis Summary of Remedial Action Alternatives

FIGURES

List of Figures

Figure 1 – Former Fort Glenn Location Map Figure 2 – OB/OD Area Details

ACRONYMS

Acronyms

ADEC Alaska Department of Environmental Conservation

ARAR applicable or relevant and appropriate requirement bgs below ground surface CERCLA Comprehensive Environmental Response, Compensation, and Liability Act CFR Code of Federal Regulations COPC chemical of potential concern DD Decision Document DGM digital geophysical mapping DoD Department of Defense EOD explosive ordnance disposal FS Feasibility Study FUDS Formerly Used Defense Sites HTRW hazardous, toxic, and radioactive waste JBER Joint Base Elmendorf

Richardson LUC land use control MC munitions constituents MD munitions debris MEC munitions and explosives of concern mm millimeter MRS Munitions Response Site MRSPP Munitions Response Site Prioritization

Protocol NCP National Oil and Hazardous Substances

Pollution Contingency Plan OB/OD Open Burn/Open Detonation PP Proposed Plan RI Remedial Investigation SI Site Inspection TNT trinitrotoluene TP Technical Paper USACE United States Army Corps of Engineers USEPA United States Environmental Protection

Agency UXO unexploded ordnance

Former Fort Glenn, Umnak Island 4

1 INTRODUCTION

This Proposed Plan1 (PP) identifies the Preferred Alternative for addressing munitions and explosives of concern (MEC) at the Open Burn/Open Detonation (OB/OD) Area at the former Fort Glenn, Umnak Island, Alaska. This PP provides the rationale for the selection of the Preferred Alternative and includes summaries of other alternatives evaluated for implementation at this site. This document is issued by the United States Army Corps of Engineers (USACE), Alaska District, the lead agency for site activities. USACE, after coordinating with the Alaska Department of Environmental Conservation (ADEC), will select the final remedy for the site after reviewing and considering all information submitted during the public comment period and the public meetings. USACE may modify the Preferred Alternative or select another response action presented in this Plan based on new information, public comments, or regulator comments.

Therefore, the public is encouraged to review and comment on all the alternatives presented in this PP.

USACE is required under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) §117(a) and National Oil and Hazardous Substances Pollution Contingency Plan (NCP) §300.430(f)(2) to issue this PP and seek public comment and participation. This PP summarizes information that can be found in greater detail in the Remedial Investigation (RI) (URS 2012) and Feasibility Study (FS) (URS 2013) Reports and other documents contained in the Administrative Record for this site. USACE and ADEC encourage the public to review these documents to gain a more comprehensive understanding of the site and investigation activities that have been conducted at the site. Stakeholder input (state regulator ADEC, public, tribal, landowners) to this PP will be documented in a Responsiveness Summary Report that will be included in a Decision Document (DD) that documents the selected remedial action.

2 SITE BACKGROUND

Fort Glenn is located on the eastern end of Umnak Island in the Fox Islands of the Aleutian Island Chain of Alaska (Figure 1). Umnak Island lies approximately 50 miles southwest of Dutch Harbor and 850 miles southwest of Anchorage, Alaska. Fort Glenn was established in 1942 as a 102,062 acre Army and defense garrison that covered the northeastern half of Umnak Island. The facility was utilized during World War II in support of the naval base at Dutch Harbor.

1 Boldfaced terms are defined in Section 12 – Glossary of Terms

The facility consisted of numerous structures, including Quonsets, revetments, metal sheds, hangars, reinforced concrete buildings, pump houses, ammunition magazines, and three airfields with support structures.

The main cantonment area consisted of three volcanic cinder runways surrounded by hangars and hardstands to park planes. Twelve camps in the main cantonment areas were utilized by infantry, field and coast artillery, ordnance department, the Army Air Forces, and others.

Historical records indicate a variety of ranges and munitions used at Fort Glenn.

A Site Inspection Report (Parsons, 2008) evaluated the entire former Fort Glenn site for the presence or absence of munitions and explosives of concern. The areas of concern have been divided into 11 separate Military Munitions Response Program projects covering a total of 292,311 acres (land and water) under the Formerly Used Defense Sites (FUDS) Program, including the 2 projects addressed in this Proposed Plan. The other areas of concern to be addressed in the future include: Suspect Burial Pit (05), Pistol Range (06), Bering Sea Bomb Target (07), Idak Range (08), Submachine Gun Range (09), Range Complex #1 (10), Range Complex #2 (11), Range Complex #3 (12), and the Discarded Military Munitions/Demo Area /Ammunition Dump (13). Three additional FUDS projects exist to address building demolition/debris removal (01), containerized hazardous, toxic, and radioactive waste (HTRW) (02), and HTRW (03).

The OB/OD Area is located in the southeastern portion of the former Fort Glenn installation (Figure 2). Fort Glenn was established in 1942 as an Army Airfield and defense garrison to support the United States Naval Base at Dutch Harbor. Fort Glenn was placed in caretaker status by late 1944 after the Japanese were driven from the Aleutian Islands during World War II.

Fort Glenn was removed from service between 1952 and 1955. The property was transferred to the Department of the Interior, Bureau of Land Management, the Alaska Department of Transportation, and to Alaska Native Corporations. Currently, the property is owned by the Aleut Corporation, the St.

George Tanaq Corporation, the State of Alaska Department of Transportation and Public Facilities, and the United States Fish and Wildlife Service. The former Fort Glenn is currently listed on the National Register of Historic Places.

In 2008, an eruption of Mount Okmok resulted in lahar being deposited across the former Fort Glenn, including approximately 70 acres of the OB/OD Area. Lahar thickness ranges from a few inches to over four feet.

In August 2001, a site visit during the preparation of an Archives Search Report noted several large craters created by demolition activity (USACE 2001). The

Former Fort Glenn, Umnak Island 5 area was described as being littered with debris, which included: electric blasting caps, an MkII hand grenade, 20 millimeter (mm) and 37mm projectiles, an armor piercing bomb (later determined to be a fragment only), fragments and components of M61 armor piercing high explosive bombs, fragmentation bombs, and other general purpose bombs.

In July 2002, an explosive ordnance disposal (EOD) team went to the site to dispose of the reported MEC (Ferris and Bivens 2002). The EOD team destroyed numerous MEC items until they expended all of their demolition materials. According to the EOD Incident Report, more MEC items remained in and around the northwestern demolition craters.

The OB/OD Area was investigated as part of a Site Inspection (SI) in 2007 (Parsons 2008). During the SI, this area was identified as the “Demolition Area” Munitions Response Site (MRS). Numerous craters were observed with unidentifiable metal fragments in the surrounding area and surface and subsurface anomalies were detected throughout the area using a Schonstedt metal detector. Areas of soil discoloration were also observed. Nine unfired 75mm projectiles were found just north of the Demolition Area MRS.

Three soil samples were collected, and one explosive compound (tetryl) and several metals were detected.

Surface water from the seep used by the ranch house for their water supply was tested, and perchlorate was detected well below its risk-based screening level.

In June and July 2011, a RI (URS 2012) was completed at the OB/OD Area to determine the nature and extent of MEC and munitions constituents (MC) contamination, and to assess the potential risks to human health and the environment. The RI fieldwork included a visual reconnaissance survey, a lahar boundary survey to determine areal extent, digital geophysical mapping (DGM) of 9.04 acres, intrusive investigation of 293 anomalies, and collection of 68 soil samples and one groundwater seep sample. During the RI, 102 MEC items were found and demolished (including the nine unfired 75mm projectiles identified during the SI), and 425 munitions debris (MD) items were found and shipped off-site for destruction by smelting.

Based on the results of the RI, the boundary of the OB/OD Area (MRS-04) was recommended to be reduced from 2,076 acres to 337 acres. The surrounding 1,739 acres were delineated into a separate project called Remaining OB/OD Area (MRS-14). A revised Inventory Project Report approved the new project designations in November 2013. The OB/OD Area (MRS-04) (337 acres) is being recommended for a response action and the Remaining OB/OD Area

(MRS-14) (1,739 acres) is being recommended for land use controls (LUCs).

In the past decade, two sets of public meetings have been held to discuss and receive public input on the Fort Glenn project. In July 2004, public meetings were held in Anchorage, Unalaska, and Nikolski. In May 2011, public meetings were held in Anchorage and Unalaska. Prior to each public meeting, fact sheets were developed and distributed in these communities and meeting notifications were published in local newspapers. In addition to public meetings, three Technical Project Planning meetings were held in Anchorage, Alaska with project stakeholders, including ADEC, United States Environmental Protection Agency (USEPA), and interested Alaska Native Corporations throughout the RI/FS process. ADEC has also participated in the RI/FS process through review and comment on plans and reports.

3 SITE CHARACTERISTICS

The OB/OD Area and Remaining OB/OD Area, consisting of 2,076 acres, are located on land owned by the State of Alaska Department of Transportation and Public Facilities. This area is surrounded by lands owned by the Aleut Corporation, the St. George Tanaq Corporation, and the United States Fish and Wildlife Service. The land is currently open with unrestricted access and the primary land use is grazing. Uses of surrounding lands include: the Bering Pacific Ranches Limited leases land on the eastern half of Umnak Island for free-range cattle grazing. The St. George Tanaq Corporation also uses land in the eastern half of Umnak Island for reindeer grazing. The population on the eastern half of Umnak Island is currently limited to Bering Pacific Ranch employees (typically five or fewer individuals who are on island seasonally). There are occasional visits to the island by scientists who study the Okmok Caldera and by reindeer hunting parties.

A total of 19 demolition craters were identified within the OB/OD Area during the RI, three in the northwest cluster and 16 in the southeast cluster. No additional demolition craters were discovered during visual reconnaissance of the site. Although only three demolition craters were visible in the northwest cluster, an additional five craters in this area have been covered by lahar from the 2008 Okmok Caldera eruption. The lahar has been estimated to cover approximately 70 acres of the site.

DGM and intrusive activities were completed to characterize the nature (type of contamination present) and extent (spread of contamination) of MEC. A total of 102 MEC items were found and demolished during the RI, and a total of 425 MD items were recovered and

Former Fort Glenn, Umnak Island 6 shipped off-site. The MEC items included 75mm projectiles; 20mm high explosive incendiary cartridges;

an MkII grenade; fragmentation bombs and components; Explosive D residue and trinitrotoluene (TNT); and fuzes. The depths of the MEC items ranged from the surface to 40 inches below ground surface (bgs). The estimated lateral extent of MEC encompasses the northeast and southwest clusters of demolition craters and surrounding kickout areas, for a total estimated area of 337 acres (i.e., OB/OD Area [MRS-04]). This acreage includes a discarded military munitions area to the north and a range-related debris washout area to the northeast that originates at a partially buried pile of M106 fuze shipping containers with erosion into a drainage feature.

The nature and extent of MC contamination was evaluated during this RI through the collection of 68 soil samples and one groundwater seep sample. The soil samples included 21 background samples for metals, 33 multi-incremental soil samples, and 14 discrete soil samples. Samples were screened against background concentrations and various health based criteria to develop a list of chemicals of potential concern. No chemicals of potential concern were identified from the multi-incremental sampling areas.

Three constituents (TNT, copper, and lead) were identified as chemicals of potential concern for human health receptors. These chemicals were detected at discrete sampling locations around discovered MEC items. Of the 14 discrete sampling locations, human health screening levels were exceeded by TNT in one sample, copper in two samples, and lead in one sample.

Zinc was detected above an ecological screening level, but was determined to not present a significant ecological risk. These detections are from localized areas around MEC items, so MC contamination is likewise expected to be localized around MEC items and not widespread across the entire site. However, MC sampling was not conducted at three demolition craters where the presence of numerous anomalies made conditions too unsafe for sampling.

Based on the results of the RI, the 2,076-acre OB/OD Area was recommended to be split into two new MRSs.

The OB/OD Area (MRS-04) (337 acres) is being recommended for a response action and the Remaining OB/OD Area (MRS-14) (1,739 acres) is being recommended for LUCs (e.g., educational awareness and five-year reviews) (see Figure 2).

It is anticipated that the remedy selected following this proposed plan will be the final action for the OB/OD Area (MRS-04). The overall strategy of USACE

Alaska District is to decrease or eliminate the potential for munitions-related accidents resulting from human interaction with MEC. This response will permanently reduce the toxicity, mobility, and volume of MEC which constitutes the principal threat at the site. Five-year reviews will ensure the remedy remains protective.

5 SUMMARY OF SITE RISKS

Based on historical data and RI field observations, potential MEC hazards have been identified at the OB/OD Area (MRS-04) (337 acres). No current site risks were identified during the RI at the Remaining OB/OD Area (MRS-14) (1,739 acres); however, due to the potential presence of MEC or MD, LUCs are being recommended.

A MEC hazard assessment was completed using the USEPA 2008 method, which takes into account the severity, accessibility, and sensitivity of potential explosives hazards. The OB/OD Area (MRS-04) has a baseline MEC hazard assessment score of 865 (out of 1,000), which results in a Hazard Level of 1 (the highest hazard level out of four levels). The primary factors leading to this high level are the presence of high and low explosive filler in fragmenting bombs, the accessibility of the site, the former use of the site for OB/OD, and the possibility of MEC including unexploded ordnance (UXO) items at the surface.

The Remaining OB/OD Area (MRS-14) was not given a MEC hazard assessment score because no MEC was identified during the RI.

Current activities at the site that were considered during the RI include agricultural (grazing by cattle or reindeer) and recreational (hunting). Potential future activities are the same, with the addition of residential use. For the current activities, potential exposure to MEC or MC would primarily be at the surface. For the future residential scenario, potential exposure could be up to 15 feet deep.

Risks were evaluated for human receptor (site worker, recreational user, and future resident) scenarios.

Chemicals of potential concern (COPCs) included TNT, copper, and lead in soils. For the site worker and recreational user, carcinogenic risk did not exceed 1x10-6, and noncarcinogenic hazard was less than 1.0.

For the future resident, potential carcinogenic risks of 3.3x10-5 were estimated based on detection of TNT at a single sample location, a noncarcinogenic hazard of 2.7 also was estimated based on copper at a single sample location, and lead slightly exceeded the residential soil cleanup level of 400 milligrams per kilogram at a single location. Since the TNT and copper results were deeper than 2.0 feet bgs, the risk is considered unlikely because the exposure is beyond the typical residential contact with surface soils (0 to 2 feet bgs).

Former Fort Glenn, Umnak Island 7

All four concentrations were measured at the source of MEC items (i.e., adjacent to or directly below the MEC item), any surrounding concentrations would be reduced via attenuating transport mechanisms.

Sampling in conjunction with isolated MEC items indicates a highly localized source, with the exposure concentration (maximum detected) biased high because the sample collected was in association with a small, single source item at depth. The actual exposure concentration can reasonably be expected to be substantially lower than the maximum concentration detected, and similarly, the associated risk or hazard would be substantially lower as well. Sampling was not conducted below other source items located within three demolition craters which were deemed unsafe to sample based on anomaly density, therefore an unknown risk exists associated with potential MC in soil.

Exposure pathways to groundwater in the OB/OD Area are considered to be potentially complete but insignificant based on both the screening results from the groundwater seep and the low frequency/localized nature of detected soil contamination that could be the source of groundwater contamination. Therefore, groundwater is no longer considered a medium of concern.

Potential ecological risks were also evaluated, and it was concluded that it is unlikely that MC pose potential risks to ecological receptors.

Data used to complete the USEPA MEC hazard assessment and human health and ecological risk assessments were also used to complete Munitions Response Site Prioritization Protocol (MRSPP) tables.

In 2005, the Department of Defense (DoD) published the MRSPP as a Federal Rule (32 Code of Federal Regulations [CFR] Part 179) to assign a relative risk priority to each defense site in the Military Munitions Response Program Inventory for response activities.

Risk is based on the overall conditions at each MRS taking into consideration various factors related to explosive safety (i.e., MEC hazards) and environmental hazards (i.e., MC contamination). In accordance with the DoD MRSPP Primer (DoD 2007), each MRS is assigned an MRSPP Priority ranging from 1 to 8.

Priority 1 indicates the highest potential hazard and Priority 8 indicates the lowest potential hazard. The overall MRSPP priority score is 3 for the OB/OD Area (MRS-04) (337 acres). The overall MRSPP priority score is No Longer Required for the Remaining OB/OD Area (MRS-14) (1,739 acres). The MRSPP worksheet tables are presented in Appendix K of the Final RI Report (URS 2012).

6 REMEDIAL ACTION OBJECTIVE

The Remedial Action Objective for the OB/OD Area (MRS-04) is:

· Reduce the potential for direct contact with MEC by human receptors, considering the current and future land use.

The MEC hazard can be mitigated by reducing the potential for direct contact through removal of MEC items and LUCs. The potential for MC risk can be mitigated by confirmation soil sampling after removal of damaged MEC items. The soil sampling results will be compared to 18 AAC 75.341 Method 2 cleanup levels to evaluate if additional action is necessary.

7 SUMMARY OF REMEDIAL

ALTERNATIVES

Eight alternatives were evaluated in the FS and are presented below. A detailed analysis of nine criteria (described in Section 8.0) and a comparative analysis, as required by the NCP, were completed for each alternative. A detailed analysis summary of the remedial action alternatives for the OB/OD Area (MRS-04) is shown in Table 1.

The Preferred Alternative for the OB/OD Area (MRS-04) is Alternative 5 – Surface Removal, Focused Subsurface Removal, and LUCs. The Preferred Alternative for the Remaining OB/OD Area (MRS-14) is Alternative 2 - LUCs.

An alternative to achieve unlimited use and unrestricted exposure was not proposed in the FS. MEC items are confirmed at depths greater than 4 feet and are possible at depths greater than 20 feet due to lahar flows and substantial demolition craters. Non-invasive technologies to detect MEC at these depths are not available. A large-scale removal of overburden to identify and remove all MEC poses unacceptable environmental risks and hazards that outweigh the potential hazards presented by MEC at this site. In addition, it would be cost-prohibitive to complete such a large-scale removal to depths greater than 4 feet over the entire 337 acres at the OB/OD Area (MRS-04).

Alternative 6 was included to evaluate a complete surface and subsurface removal over the entire 337 acres, but was not considered a UU/UE alternative because known MEC items may be present at depths greater than 4 feet and up to 20 feet under lahar areas.

Thus, LUCs would still be required.

7.1 Alternative 1: No Action

Alternative 1 assumes that no further action would be taken regarding MEC at the OB/OD Area (MRS-04).

This alternative is required by the NCP and it serves as

Former Fort Glenn, Umnak Island 8 a baseline against which the other alternatives are compared (40 CFR 300.430[e][6]).

Estimated Costs for Alternative 1:

Capital Cost: $0 Recurring 5-Year Review Costs for 30 Years: $0 Total Cost of Alternative: $0

7.2 Alternative 2: LUCs

Alternative 2 would implement LUCs that are intended to increase awareness of potential risks at the OB/OD Area (MRS-04) and Remaining OB/OD Area (MRS-

14) through administrative and engineering controls.

Administrative controls would consist of an educational awareness program and an inspection and maintenance program. An educational awareness program, with a goal of modifying behavior to reduce the risk of exposure or the impact if exposure occurs, would be implemented through an updated Public Involvement Plan. The interested parties listed in the Public Involvement Plan (e.g., Alaska Native Corporations, Bering Pacific Ranch, residents of Nikolski and Unalaska) would receive fact sheets and be invited to periodic public meetings. Commercial enterprises that organize hunting or hiking trips to the Fort Glenn area would also be contacted. The administrative controls would be maintained every 5 years by mailings to the identified parties, queries to address potential land use changes, and updates of the contact list. The landowner will also be requested to implement a notice of environmental contamination which documents the area which may contain residual MEC items. USACE will provide the landowner with available data and assist with implementation. Engineering controls may consist of warning signs placed around the OB/OD Area (MRS-04) and Remaining OB/OD Area (MRS-14) and along access roads, if requested by the landowners to inform potential receptors of the presence of MEC.

Five-year reviews would be conducted to evaluate the continued effectiveness of the administrative and engineering controls. A site inspection would be conducted as part of each 5-year review to make sure site conditions had not changed. The 5-year review would be documented and the Fort Glenn Administrative Record would be updated.

Estimated Costs for Alternative 2:

Capital Cost: $428,553 Recurring 5-Year Review Costs for 30 Years:

$102,446 (per event) Total Cost of Alternative: $1,043,229

Alternative 3 includes the administrative and engineering controls described for Alternative 2, with the addition of a focused MEC surface removal. The surface removal would involve removal, inspection, and disposal of MEC from the focus area, which is approximately 30 acres of land around the former demolition craters with the highest concentrations of MEC at the site. This alternative would reduce surface MEC hazards within the focus area, but would not reduce potential subsurface MEC hazards or potential surface MEC hazards in the remainder of the site surrounding the focus area. LUCs would address these remaining potential MEC hazards.

The focused surface removal would be completed by UXO technicians qualified in accordance with Technical Paper (TP) 18 (DDESB 2004), using hand-held detectors, and metal visible on the ground surface or found to protrude through the mineral soil layer into vegetation would be removed. Vegetation removal (i.e., mowing) may or may not be required to clear the area for the surface removal, depending on the time of year and density of vegetative cover. Recovered MEC and MD would be managed, stored, shipped, disposed of by detonation with consolidated shots, and demilitarized in accordance with the approved project plans and safety submittals. Typically, MEC would be destroyed on-site through controlled demolition and MD would be shipped off-site for destruction and recycling.

The effectiveness of this alternative requires future site inspections, which are included every 5 years after the focused surface removal action. Five-year reviews, to include a site inspection, would be conducted to evaluate the continued effectiveness and permanence of the alternative. The 5-year reviews would be documented and the Fort Glenn Administrative Record would be updated.

Estimated Costs for Alternative 3:

Capital Cost: $1,240,725 Recurring 5-Year Review Costs for 30 Years:

$102,446 (per event) Total Cost of Alternative: $1,855,401

Alternative 4 includes the administrative and engineering controls described for Alternative 2, with the addition of a MEC surface removal. The surface removal would involve removal, inspection, and disposal of MEC from the entire 337-acre site. This alternative would reduce surface MEC hazards, but would not reduce potential subsurface MEC hazards.

Former Fort Glenn, Umnak Island 9

LUCs would address these remaining potential MEC hazards.

The surface removal would be completed by UXO technicians qualified in accordance with TP 18 (DDESB 2004) using hand-held detectors, and metal visible on the ground surface or found to protrude through the mineral soil layer into vegetation would be removed. Vegetation removal (i.e., mowing) may or may not be required to clear the area for the surface removal, depending on the time of year and density of vegetative cover. Recovered MEC and MD would be managed, stored, shipped, disposed of by detonation with consolidated shots, and demilitarized in accordance with the approved project plans and safety submittals. Typically, MEC would be destroyed on-site through controlled demolition and MD would be shipped off-site for destruction and recycling. Soil confirmation sampling will be conducted during the MEC removal activities to verify the identified COPCs (TNT, copper, lead, and zinc) do not present a risk.

The effectiveness of this alternative requires future site inspections, which are included every 5 years after the surface removal action. Five-year reviews, to include a site inspection, would be conducted to evaluate the continued effectiveness and permanence of the alternative. The 5-year reviews would be documented and the Fort Glenn Administrative Record would be updated.

Estimated Costs for Alternative 4:

Capital Cost: $4,844,519 Recurring 5-Year Review Costs for 30 Years:

$102,446 (per event) Total Cost of Alternative: $5,459,195

Alternative 5 includes the components of Alternative 4, with the addition of a focused MEC subsurface removal at the 30-acre focus area. The subsurface removal would be to the depth of detection of the metal detector selected for the response action. Reliable depths of detection range from a few inches for small, 20mm rounds to several feet for larger projectiles and bombs.

This alternative would reduce surface MEC hazards across the entire 337-acre site. It would also reduce subsurface MEC hazards within the focus area, but would not reduce subsurface MEC hazards beyond the focus area. LUCs would address these remaining potential MEC hazards.

The surface removal would be completed as described under Alternative 4. The focused subsurface removal would begin after the surface removal is completed.

Subsurface removal activities would include a comprehensive geophysical survey in order to acquire subsurface anomalies potentially representing MEC.

Geophysical data would include RI DGM survey data, additional DGM survey data, and analog geophysical data where vegetation and terrain inhibit the positioning quality of DGM surveying. The subsurface removal would be conducted by UXO technicians qualified in accordance with TP 18 (DDESB 2004) using hand-held detectors, shovels, and/or earth-moving machinery.

Recovered MEC and MD would be managed, stored, shipped, disposed of by detonation with consolidated shots, and demilitarized in accordance with the approved project plans and safety submittals.

Typically, MEC would be destroyed on-site through controlled demolition and MD would be shipped off-site for destruction and recycling. Soil confirmation sampling will be conducted during the MEC removal activities to verify the identified COPCs (TNT, copper, lead, and zinc) do not present a risk.

The effectiveness of this alternative requires future site inspections, which are included every 5 years after the surface and focused subsurface removal actions. Five-year reviews, to include a site inspection, would be conducted to evaluate the continued effectiveness and permanence of the alternative. The 5-year reviews would be documented and the Fort Glenn Administrative Record would be updated.

Estimated Costs for Alternative 5:

Capital Cost: $8,905,275 Recurring 5-Year Review Costs for 30 Years:

$102,446 (per event) Total Cost of Alternative: $9,519,951

Alternative 6 includes the components of Alternative 4 with the addition of a MEC subsurface removal from the entire 337-acre site. The subsurface removal would be to the depth of detection of the metal detector selected for the response action. Reliable depths of detection range from a few inches for small, 20mm rounds to several feet for larger projectiles and bombs.

This alternative would reduce surface and subsurface MEC hazards across the entire 337-acre site. LUCs would address the potential of any remaining MEC that is deeper than the depth of removal or not found during the removal action.

The surface removal would be completed as described under Alternative 4. The subsurface removal would begin after the surface removal is completed.

Subsurface removal activities would include a comprehensive geophysical survey in order to acquire subsurface anomalies potentially representing MEC.

Former Fort Glenn, Umnak Island 10

Geophysical data would include RI DGM survey data, additional DGM survey data, and analog geophysical data where vegetation and terrain inhibit the positioning quality of DGM surveying. The subsurface removal would be conducted as described under Alternative 5.

The effectiveness of this alternative requires future site inspections, which are included every 5 years after the surface and subsurface removal actions. Five-year reviews, to include a site inspection, would be conducted to evaluate the continued effectiveness and permanence of the alternative. The 5-year reviews would be documented and the Fort Glenn Administrative Record would be updated.

Estimated Costs for Alternative 6:

Capital Cost: $31,475,343 Recurring 5-Year Review Costs for 30 Years:

$102,446 (per eventl) Total Cost of Alternative: $32,090,018

Alternative 7 includes the components of Alternative 4 with the addition of a soil cover over the 30-acre focus area. The surface removal would involve removal, inspection, and disposal of MEC from the entire 337-acre site. This alternative would reduce surface MEC hazards, but would not reduce potential subsurface MEC hazards. The soil cover would reduce the potential for MEC to migrate to the surface in the focus area. LUCs would address the remaining potential MEC hazards.

The surface removal would be completed as described under Alternative 4.

Prior to construction of the soil cover, a topographic survey would be required to form the basis for the design. The topographic survey would be completed immediately after surface removal. It is assumed that the time required to complete the design would extend beyond the initial field season, so a second field season to construct the soil cover would be required. The soil cover would be installed to form a minimum 2-foot thick soil barrier over the 30-acre focus area. An estimated 114,800 compacted cubic yards of soil would be required, using locally available fill. Following final grading, the soil cover would be seeded with native vegetation.

The effectiveness of this alternative requires future site inspections, which are included every 5 years after the surface removal action and focused soil cover. Five-year reviews, to include a site inspection, would be conducted to evaluate the continued effectiveness and permanence of the alternative. The 5-years review would be documented and the Fort Glenn Administrative Record would be updated.

Estimated Costs for Alternative 7:

Capital Cost: $10,384,877 Recurring 5-Year Review Costs for 30 Years:

$102,446 (per event) Total Cost of Alternative: $10,999,553

Alternative 8 includes the focused surface removal of Alternative 3, the focused subsurface removal of Alternative 5, and the LUCs of Alternative 2. The surface removal would involve removal, inspection, and disposal of MEC from the 30-acre focus area. The subsurface removal would be to the depth of detection of the metal detector selected for the response action.

Reliable depths of detection range from a few inches for small, 20mm rounds to several feet for larger projectiles and bombs. This alternative would reduce surface and subsurface MEC hazards across the entire focus area. LUCs would address the potential of any remaining MEC that is below the depth of detection, not found during the focused removal actions, or located in the remainder of the site surrounding the focus area.

The focused surface removal would be completed as described under Alternative 3. The focused subsurface removal would begin after the surface removal is completed, as described under Alternative 5.

The effectiveness of this alternative requires future site inspections, which are included every 5 years after the focused surface and subsurface removal actions. Five-year reviews, to include a site inspection, would be conducted to evaluate the continued effectiveness and permanence of the alternative. The 5-year reviews would be documented and the Fort Glenn Administrative Record would be updated.

Estimated Costs for Alternative 8:

Capital Cost: $7,454,649 Recurring 5-Year Review Costs for 30 Years:

$102,446 (per event) Total Cost of Alternative: $8,069,325

8 EVALUATION OF

ALTERNATIVES

Nine evaluation criteria are statutory criteria required by the NCP (40 CFR 300) and described in the Guidance for Conducting Remedial Investigations and Feasibility Studies under the Comprehensive Environmental Response, Compensation, and Liability

Former Fort Glenn, Umnak Island 11

A c t (USEPA 1988). The nine criteria were used to evaluate the different alternatives individually and against each other in order to select a remedy. These nine criteria are segregated into three groups and are briefly described below.

Threshold criteria are requirements that each alternative must meet in order to be selected. There are two threshold criteria, as listed below:

· Overall Protection of Human Health and the Environment determines whether an alternative eliminates, reduces, or controls threats to public health and the environment.

· Compliance wi th Applicable or Relevant and Appropriate Requirements (ARARs) evaluates whether the alternative meets federal and state environmental statutes, regulations, and other requirements that pertain to the site, or whether a waiver is justified. No applicable ARARs were identified in the FS.

However, soil confirmation samples will be collected after removal of damaged MEC items and analyzed for TNT, copper, lead, and zinc. Analytical results will be compared to 18 AAC 75, Table B1, direct contact, over 40 inch zone cleanup levels.

In addition, for alternatives which identify the use of consolidated shots, the Resource Conservation and Recovery Act (RCRA), Subpart X is a relevant and appropriate requirement.

Primary balancing criteria are used to weigh major trade-offs among alternatives. There are five balancing criteria, as listed below:

· Short-Term Effectiveness considers the length of time needed to implement an alternative and the risks the alternative poses to workers, residents, and the environment during implementation.

· Long-Term Effectiveness and Permanence considers the ability of an alternative to maintain protection of human health and the environment over time.

· Reduction of Volume, Toxicity, and Mobility through Treatment evaluates an alternative’s use of treatment to reduce the harmful effects of principal contaminants, their ability to move in the environment, and the amount of contamination present.

· Implementability considers the technical and administrative feasibility of implementing the alternative, including factors such as the relative availability of goods and services.

· Cost includes estimated capital and annual operations and maintenance costs. Cost estimates are expected to be accurate within a range of +50% to –30%.

Modifying criteria may be considered to the extent that information is available during the FS, but can be fully considered only after public comment is received on the PP. In the final balancing of trade-offs among alternatives upon which the final remedy selection is based, modifying criteria are of equal importance to the balancing criteria. There are two modifying criteria, as listed below:

· State Acceptance considers whether the state agrees with the USACE analyses and recommendations, as described in the FS and this

PP.

· Community Acceptance considers whether the local community agrees with the USACE analyses and Preferred Alternative. Comments received on the PP are an important indicator of community acceptance.

An evaluation of the eight alternatives requiring detailed analysis was conducted against the nine criteria identified above. In addition, an analysis was conducted to compare the alternatives against each other in order to determine the Preferred Alternative. The detailed analysis summary can be found in Table 1.

9 PREFERRED ALTERNATIVE

Based on the evaluation of the alternatives with respect to the threshold and balancing criteria and in comparison with each other, the Preferred Alternative for the OB/OD Area (MRS-04) is Alternative 5 – Surface Removal, Focused Subsurface Removal, and LUCs. The USACE believes that Alternative 5 meets the threshold criteria and provides the best balance of trade-offs among the other alternatives with respect to the balancing and modifying criteria. The USACE expects the Preferred Alternative to satisfy the following statutory requirements of CERCLA §121(b): (1) be protective of human health and the environment; (2) comply with ARARs (or justify a waiver); (3) be cost-effective; (4) utilize permanent solutions and alternative treatment technologies or resource recovery technologies to the maximum extent practicable; and (5) satisfy the preference for treatment as a principal element, or explain why the preference for treatment will not be met.

The elements of this alternative are technically and administratively feasible, but require specialized personnel and equipment to implement. A detailed work plan and a safety submittal must be developed.

Alternative 5 achieves the balancing factors of long-term effectiveness, permanence, and reduction of

Former Fort Glenn, Umnak Island 12 explosives hazards through MEC removal from the surface and subsurface of the focus area, the primary location where MEC has been found. The other elements of Alternative 5 (LUCs including an educational awareness program, warning signs if requested, notice of environmental contamination, and periodic inspection and maintenance program), provides additional protection from the residual risks that are not addressed by the removal action. The five-year review process also evaluates the effectiveness of the implemented remedy to ensure protectiveness.

The Preferred Alternative for the Remaining OB/OD Area (MRS-14) is Alternative 2 – LUCs. The community will provide its comments during the public comment period. The Preferred Alternatives can change in response to public comment or new information obtained for the sites.

10 COMMUNITY PARTICIPATION

Information regarding the cleanup at the OB/OD Area (MRS-04) is provided to the public through the issuance of information and documents to property owners, the Administrative Record file for the site, and announcements published in the Anchorage Daily News and Dutch Harbor Fisherman newspapers. The public is encouraged to refer to these sources to stay informed on issues pertaining to the restoration activities.

In accordance with the NCP, an Administrative Record file has been established for the former Fort Glenn.

The contents of the file include a variety of written material, such as pieces of correspondence, data reports, assessments, plans, newspaper articles, notices, and fact sheets. The Administrative Record files are located at the Information Repositories (e.g., Alaska Resources Library & Information Services and Unalaska Public Library).

USACE is soliciting input from the community on this PP. The comment period will extend from May 1, 2014 through June 2, 2014. Written comments must be postmarked no later than the last day of the public comment period, which is June 2, 2014. Comments or questions concerning this PP, or the Preferred Alternative, should be addressed to Ms. Valerie Palmer.

During the comment period, two public meetings will be held to present the PP and to answer questions relevant to the PP. Following the public meetings, the comments received on this PP will be summarized and responses provided in the Responsiveness Summary section of the DD. The DD will present the final selected remedy for the site.

Public Comment Period May 1 – June 2, 2014

Public Meetings

May 6, 2014 Anchorage

May 7, 2014 Unalaska

Contact for Comments/Questions?

U.S. Army Corps of Engineers

Alaska District Ms. Valerie Palmer (PM-ESP-FUDS)

P.O. Box 6898 JBER, Alaska 99506-0898

Phone: 907-753-2578 POA-FUDS@usace.army.mil

Information Repositories Alaska Resources Library &

Information Services Library Building, Suite 111

3211 Providence Drive Anchorage, Alaska 99508

Phone: (907) 272-7547

Unalaska Public Library 64 Eleanor Street

Unalaska, Alaska 99685 Phone: (907) 581-5060

11 REFERENCES

Department of Defense (DoD). 2007. Munitions Response Site Prioritization Protocol Draft Primer, Office of the Deputy Under Secretary of Defense Installations and Environment, Office of Environmental Management. April.

Department of Defense Explosives Safety Board (DDESB). 2004. Minimum Qualifications for Unexploded Ordnance (UXO) Technicians and Personnel. December.

Ferris and Bivens. 2002. SSG Tom Ferris and SGT John Bivens. 24-29 Jul 02 Combined Incident to Kodiak and Fort Glenn, Alaska. July.

Parsons. 2008. Site Inspection: Former Fort Glenn, Umnak and Unalaska Islands, Alaska. Final Revision 3.

5 September.

URS Group, Inc. (URS). 2012. Final Remedial Investigation of OB/OD Area. Former Fort Glenn.

Former Fort Glenn, Umnak Island 13

Umnak Island, Alaska. F10AK029804_03.10_0500_a 200-1e. 23 March.

URS. 2013. Final, Revision 2, Feasibility Study of OB/OD Area. Former Fort Glenn. Umnak Island, Alaska. F10AK029804_04.09_0500_a. December.

United States Army Corps of Engineers (USACE), St.

Louis District. 2001. Archives Search Report Findings for Fort Glenn, Umnak Island, Alaska. September.

United States Environmental Protection Agency (USEPA). 1988. Guidance for Conducting Remedial Investigations and Feasibility Studies under the Comprehensive Environmental Response, Compensation, and Liability Act.

USEPA. 2008. MEC Hazard Assessment Methodology (Interim). October.

12 GLOSSARY OF TERMS

Administrative Record: A compilation of all documents relied upon to select a remedial action pertaining to the investigation and remediation of the project site.

Anomaly: Any identified subsurface mass that may be geologic in origin, MEC/MD, or some other man-made material. Such identification is made through geophysical investigation and reflects the response of the sensor used to conduct the investigation.

Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, otherwise known as Superfund): A federal law that addresses the funding for and remediation of abandoned or uncontrolled hazardous waste sites. This law also establishes criteria for the creation of key documents such as the RI, FS, PP, and DD.

Decision Document (DD): The USACE uses the term “Decision Document” for the documentation of remedial response decisions at FUDS properties.

Concurrence on the DD by USEPA or the state regulatory agency is sought and the Army approves the document.

Ecological Receptor: A plant, animal, or ecosystem exposed to an adverse condition.

Feasibility Study (FS): A FS evaluates possible remedies using the information generated from the RI.

The FS becomes the basis for selection of a remedy that effectively eliminates the threat posed by contaminants at the site.

Human Receptor: A hypothetical person, based on current or potential future land use, that may be exposed to an adverse condition.

Lahar: A moving fluid mass composed of volcanic debris and water. Lahar deposited in 2008 covers approximately 70 acres of the OB/OD Area (MRS-04), and it ranges in…