roi-namur pol yard removal action …...roi-namur pol yard removal action memorandum/ feasibility...

ROI-NAMUR POL YARD

REMOVAL ACTION MEMORANDUM/

FEASIBILITY STUDY

U.S. ARMY KWAJALEIN ATOLL/REAGAN TEST SITE,

REPUBLIC OF MARSHALL ISLANDS

Site ID CCKWAJ-003

JULY 2012

Contract No. DASG60-03-C-0081

Prepared for:

U. S. Army Space and Missile Defense Command

Von Braun Complex

Building 5220

Redstone Arsenal, Alabama 35898

Prepared by:

3150 C Street, Suite 250

Anchorage, Alaska 99503

DISTRIBUTION STATEMENT A. Approved for public release. Distribution is unlimited.

[THIS PAGE LEFT INTENTIONALLY BLANK]

Final Roi-Namur POL Yard RAM Sivuniq, Inc.

Kwajalein Atoll/Reagan Test Site i July 2012

TABLE OF CONTENTS

EXECUTIVE SUMMARY .................................................................................................... ES-1

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

1.1 Project Information .............................................................................................. 1-1

1.2 Physical and Environmental Setting .................................................................... 1-3

1.2.1 Environmental Setting ................................................................................... 1-3 1.2.2 Climate ........................................................................................................... 1-3

1.2.3 Regional Geology .......................................................................................... 1-4 1.2.4 Soil Characteristics ........................................................................................ 1-5 1.2.5 Hydrogeology ................................................................................................ 1-5

1.3 Site Description and History ................................................................................ 1-6

1.3.1 Site History .................................................................................................... 1-7

1.4 Removal Action Objective ................................................................................... 1-7

2.0 PRE-DESIGN ACTIVITIES TO DATE ..................................................................... 2-1

2.1 Previous Investigations ........................................................................................ 2-1

2.1.1 Conceptual Site Model ................................................................................... 2-9

2.2 Cultural Resource Assessment ........................................................................... 2-11

3.0 APPLICABLE REMEDIAL TECHNOLOGIES ..................................................... 3-13

3.1 Scope and Purpose of Removal Action ............................................................. 3-13

3.2 Justification for the Proposed Action ................................................................. 3-14

3.3 Technology Identification and Description ....................................................... 3-15

3.3.1 NAPL Removal Options .............................................................................. 3-18 3.3.2 Remedial Options......................................................................................... 3-23

4.0 ENGINEERING EVAULATION AND COST ANALYSIS OF

ALTERNATIVES .......................................................................................................... 4-1

4.1 NAPL Removal Options ...................................................................................... 4-1

4.1.1 Dual Phase Extraction .................................................................................... 4-1 4.1.2 Bioslurping ..................................................................................................... 4-5

4.1.3 Infiltration Galleries ....................................................................................... 4-7

4.2 Remedial Options............................................................................................... 4-10

4.2.1 Enhanced Bioremediation ............................................................................ 4-10 4.2.2 Thermal Treatment....................................................................................... 4-15

4.3 Comparative Analysis of Alternatives ............................................................... 4-17

4.3.1 NAPL Removal ............................................................................................ 4-18

4.3.2 Remedial Technologies ................................................................................ 4-19

4.4 Remedy of Record ............................................................................................. 4-20

4.5 Cultural Resource Evaluation ............................................................................ 4-21

5.0 FUTURE PRE-REMOVAL ACTION ACTIVITIES ................................................ 5-1

6.0 REMOVAL ACTION SYSTEM DESIGN PROCESS .............................................. 6-1

6.1 Removal and Remedial Action System Elements ............................................... 6-1

6.2 Design and Performance Criteria ......................................................................... 6-2


Kwajalein Atoll/Reagan Test Site ii July 2012

6.2.1 Cleanup Goals ................................................................................................ 6-2

6.2.2 Performance Criteria ...................................................................................... 6-3

6.3 System Design Concepts...................................................................................... 6-5

6.3.1 Infiltration Galleries ....................................................................................... 6-5 6.3.2 Enhanced Bioremediation ............................................................................ 6-11

6.4 Schedule ............................................................................................................. 6-11

7.0 PROPOSED WORK SUMMARY ............................................................................... 7-1

7.1 General Field Activities ....................................................................................... 7-1

7.2 Restoration Activities Approach .......................................................................... 7-2

7.2.1 Supplemental Data Collection ....................................................................... 7-3 7.2.2 Subsurface Modeling and Design Finalization .............................................. 7-3 7.2.3 Construction of Infiltration Galleries ............................................................. 7-3

7.2.4 Installation of NAPL Extraction Equipment.................................................. 7-3 7.2.5 Infiltration Galleries System Startup ............................................................. 7-4 7.2.6 NAPL Removal Monitoring and Operation ................................................... 7-4

7.2.7 Contaminated Soil Landfarming .................................................................... 7-4 7.2.8 NAPL Removal Verification Assessment and Reporting .............................. 7-5

7.2.9 Installation of Injection Wells ........................................................................ 7-5 7.2.10 Installation of Sparging Equipment and Pumps............................................. 7-6 7.2.11 Enhanced Bioremediation System Startup ..................................................... 7-6

7.2.12 Long-Term Monitoring .................................................................................. 7-6 7.2.13 Project Reporting ........................................................................................... 7-7

7.3 Sampling and Analysis Plan ................................................................................ 7-7

7.4 Quality Assurance Project Plan ......................................................................... 7-10

7.4.1 Data Quality Objectives ............................................................................... 7-11

7.5 Site Safety and Health Plan ................................................................................ 7-14

7.6 Archaeological Monitoring Plan ........................................................................ 7-16

8.0 REFERENCES ............................................................................................................... 8-1


Kwajalein Atoll/Reagan Test Site iii July 2012

LIST OF TABLES

Table 1-1 Document Crosswalk ................................................................................................ 1-2

Table 2-1 Frequency and Magnitude of Compounds Detected During the 2010/11 SI ............ 2-4

Table 2-2 Roi-Namur Plan Spill Site CSM ............................................................................... 2-9

Table 3-1 FRTR Screening Matrix Preferred Options ............................................................ 3-16

Table 4-1 DPE Effectiveness Evaluation .................................................................................. 4-3

Table 4-2 Infiltration Galleries Effectiveness Evaluation ......................................................... 4-9

Table 4-3 Enhanced Bioremediation Effectiveness Evaluation .............................................. 4-13

Table 4-4 Thermal Treatment Effectiveness Evaluation ......................................................... 4-16

Table 6-1 Current and Target COC Concentrations .................................................................. 6-3

Table 7-1 Field Screening Methods for Soils ............................................................................ 7-8

Table 7-2 Field Screening Methods for Water .......................................................................... 7-8

Table 7-3 Laboratory Analytical Methods for Soils ................................................................. 7-9

Table 7-4 Laboratory Analytical Methods for Water ................................................................ 7-9

Table 7-5 Quality Control Parameters Corresponding to Data Quality Indicators ................. 7-12

Table 7-6 Hazard Analyses for General Jobsite Activities ..................................................... 7-15

LIST OF FIGURES

Figure 1-1 Roi-Namur POL Yard Spill Site Overview ............................................................... 1-9

Figure 2-1 Roi-Namur POL Yard Soil Boring Locations and Analytical Detections ................. 2-5

Figure 2-2 Roi-Namur POL Yard Piezometer Locations and Analytical Detections ................. 2-6

Figure 2-3 Roi-Namur POL Yard Product Thickness Map ......................................................... 2-7

Figure 2-4 Roi-Namur POL Yard DRO Plume in Groundwater ................................................. 2-8

Figure 2-5 Roi-Namur Island Freshwater Lens and Dredge Fill Map....................................... 2-12

Figure 3-1 Flow Diagram for DPE ............................................................................................ 3-21

Figure 3-2 Bioslurping Flow Diagram ...................................................................................... 3-22

Figure 6-1 Infiltration Gallery Side View and Installation Procedure ........................................ 6-8

Figure 6-2 Infiltration Gallery Planning-Level Schematic .......................................................... 6-9

Figure 6-3 Proposed Initial Locations for Infiltration Gallery Installation ............................... 6-10

LIST OF APPENDICES

Appendix A Schedule

Appendix B RACER Supporting Documentation

Appendix C Detailed Evaluation of Remedial Technologies

Appendix D Soil Boring Logs

Appendix E Cultural Resource Evaluation


Kwajalein Atoll/Reagan Test Site iv July 2012

LIST OF ACRONYMS AND ABBREVIATIONS

% percent

%D percent difference

%Df percent drift

%R percent recovery

AMP Archaeological Monitoring Plan

ARSTRAT U.S. Army Forces Strategic Command

AST aboveground storage tank

ATSC Atmospheric Technology Services Company

bgs below ground surface

°C degrees Celsius

CEMML Center for Environmental Management of Military Lands

cm2

square centimeters

cm3/g cubic centimeters per gram

COC contaminant of concern

CRE Cultural Resource Evaluation

CSM conceptual site model

CY cubic yard

DCE dichloroethene

DEP Document of Environmental Protection

DO dissolved oxygen

DoD U.S. Department of Defense

DPE dual phase extraction

DQO data quality objectives

DQI data quality indicators

DRO diesel range organics

EE/CA Engineering Evaluation/Cost Analysis

EPA U.S. Environmental Protection Agency

ESL environmental screening level

°F degrees Fahrenheit

FRTR Federal Remediation Technologies Roundtable

FS Feasibility Study

g/cm3 grams per cubic centimeter

g/mL grams per milliliter

GIS Geographic Information System


Kwajalein Atoll/Reagan Test Site v July 2012

GEPA Guam Environmental Protection Agency

GRO gasoline range organics

HDH Hawai‟i Department of Health

ICBM intercontinental ballistic missile

KMR Kwajalein Missile Range

LCS/LCSD laboratory control sample/laboratory control sample duplicate

LNAPL light non-aqueous phase liquids

LOEL lowest observed effect level

µg microgram

µg/L micrograms per liter

µg/kg micrograms per kilogram

MCL maximum contaminant level

mg/kg milligram per kilogram

mg/L milligrams per liter

mi2 square miles

mmHg millimeters of mercury

mph miles per hour

MS/MSD matrix spike/matrix spike duplicate

MSL mean sea level

NA not analyzed

NAPL non-aqueous phase liquid

NC not calculated

NFA no further action

NOAA National Ocean and Atmospheric Administration

O2 oxygen

ORNL Oak Ridge National Laboratory

PAH polycyclic aromatic hydrocarbon

pH hydrogen concentration

PID photoionization detector

PMRF Pacific Missile Range Facility

POL petroleum, oil, and lubricants

ppm parts per million

PRG Preliminary Remediation Goal

QAPP Quality Assurance Project Plan

QC quality control

RACER Remedial Action Cost Engineering and Requirements


Kwajalein Atoll/Reagan Test Site vi July 2012

RAM Removal Action Memorandum

RC response complete

RFH Radio frequency heating

RMI Republic of the Marshall Islands

RPD relative percent difference

RSE Raytheon Service Company Range Systems Engineering

RSL Regional Screening Levels

RTS Reagan Test Site

SAP Sampling Analysis Plan

SI site investigation

SMDC U.S. Army Space and Missile Defense Command

SQuiRTs Screening Quick Reference Tables (NOAA)

SSHP Site Safety and Health Plan

SVE soil vapor extraction

SVOC semivolatile organic compound

TEO U.S. Army Test and Evaluation Office

TOC total organic carbon

TPH total petroleum hydrocarbons

UCL95 95% upper confidence level

UES U.S. Army Kwajalein Atoll Environmental Standards

USACE U.S. Army Corps of Engineers

USAEHA U.S. Army Environmental Hygiene Agency

USAKA U.S. Army Kwajalein Atoll

USGS U.S. Geological Survey

VOC volatile organic compound

VPH volatile petroleum hydrocarbon

WWII World War II


Kwajalein Atoll/Reagan Test Site ES-1 July 2012

EXECUTIVE SUMMARY

This document provides a Removal Action Memorandum (RAM)/Feasibility Study (FS)

pursuant to requirements in the U.S. Army Kwajalein Atoll (USAKA) Environmental Standards

(UES) section 3-6.5.8(g) for proposed nonaqueous phase liquid (NAPL) product removal. This

document outlines a Feasibility Study (FS) as described in UES 3-6.5.8(n) for future remediation

at the Roi-Namur Petroleum, Oils and Lubricants (POL) Yard Spill Site on Kwajalein Atoll,

Republic of the Marshall Islands. The NAPL removal is included as part of the RAM/FS, as it is

a time-critical action since it must be removed before other remedial options can be

implemented.

The Roi-Namur POL Yard site is the primary fuel storage area for the power plant containing

two storage tanks (ASTs) (Facilities 8046 and 8047). A large diesel fuel oil release of

approximately 22,500 gallons occurred on January 30, 1996. Emergency response and follow-up

recovery activities yielded almost 17,000 gallons, or approximately 75% of the spill volume.

Prior to the fuel release, several sites of potential environmental contamination were identified

(USAHEA, 1991). These included an unlined oil/solvent storage pit to the south of the POL

storage tanks, and a wash rack discharge ditch to the north and east of the POL storage tanks.

In 2010 and 2011, Sivuniq conducted a follow-up Site Investigation (SI), which included soil and

groundwater sampling. The SI revealed that soil and groundwater contamination remains at the

site, including over a foot of NAPL on the groundwater surface in the most contaminated area.

Contaminants were also identified in piezometers at concentrations below screening levels that

were installed on the beach, indicating that that future monitoring should be performed to

determine the extent of the impact to the lagoon. The primary contaminant in soil and

groundwater was diesel range organics (DRO), although concentrations of gasoline range

organics (GRO), benzo(a)anthracene, naphthalene, and phenanthrene exceeded applicable

screening criteria in soil.

Three alternatives were evaluated for the NAPL removal action:

Alternative 1 – Dual Phase Extraction

Alternative 2 – Bioslurping

Alternative 3 – Infiltration Galleries


Kwajalein Atoll/Reagan Test Site ES-2 July 2012

Two alternatives were evaluated for remediation of residual contamination:

Alternative 1 – Enhanced Bioremediation

Alternative 2 – Thermal Treatment

Comparisons of effectiveness, implementability, and costs indicate that a treatment train of

infiltration galleries followed by enhanced bioremediation would be the most cost effective

strategy for NAPL removal and residual remediation at the Roi-Namur POL Yard Spill Site.

The NAPL removal action will be the first phase implemented at the site, scheduled for early

2012. While NAPL removal begins, Sivuniq will initiate landfarming for excavated soils and

also begin to install enhanced bioremediation injection wells at the edge of the contaminant

plume. As NAPL is removed from the source area, the area covered by injection wells will be

expanded.

Sivuniq also proposed additional assessment to be performed prior to the NAPL removal action.

The supplemental site investigation began in December 2011, and will focus on delineating the

lateral extent of soil and groundwater contamination around the site. Soil samples will be

collected from borings advanced outside of the 2011 perimeter borings that indicated

contamination was present. Permanent groundwater monitoring wells will be installed for long-

term monitoring of the groundwater contamination, water table elevation, and groundwater flow

direction. In addition, data to support the development of an enhanced bioremediation design

plan (i.e., nutrient requirements and formation details) will be collected.


Kwajalein Atoll/Reagan Test Site 1-1 July 2012

1.0 INTRODUCTION

1.1 PROJECT INFORMATION

The Kwajalein Atoll is located in western chain of the Marshall Islands in the Pacific Ocean, just

west of the international dateline. It is 2,100 nautical miles southwest of Honolulu, Hawaii and

approximately 4,200 nautical miles southwest of San Francisco, California. Less than 700 miles

north of the equator, Kwajalein is in the latitude of Panama and the southern Philippines, and in

the longitude of New Zealand (2,300 miles south), and the Kamchatka Peninsula of the former

Soviet Union (2,600 miles north). Kwajalein, at the atoll‟s southern tip, and Roi-Namur, at its

northern extremity, are the principal islands at U.S. Army Kwajalein Atoll (USAKA)/ Ronald

Reagan Ballistic Missile Defense Test Site (RTS) and are 50 miles apart; the other islands used

by USAKA/RTS are situated between these two. The atoll‟s remoteness from centers of

population and proximity to the sea has a major bearing on the operation and maintenance of

USAKA/RTS.

The U.S. Army utilizes 11 of the over 100 islands in the atoll, with active facilities on all or part

of the eleven islands (one of which is Roi-Namur). Two of the islands, Kwajalein and Roi-

Namur, were sites of extensive battles during World War II (WWII); thus, investigation and

remediation activities are further complicated by potential unexploded ordnance (UXO) and

cultural/historical resource discoveries, including human remains.

This document is described as a Removal Action Memorandum (RAM)/Feasibility Study (FS)

pursuant to U.S. Army Kwajalein Atoll Environmental Standards (UES) 3-6.5.8(g), and also

includes elements of a Feasibility Study (FS) report pursuant to UES 3-6.5.8(n). Table 1-1

presents how the elements for these documents are included in this RAM/FS. The document

includes elements for both RAMs and FSs because there are two proposed phases for

remediation at the site: a time-critical removal action for NAPL reduction that must occur before

other remedial options are implemented (covered by the RAM/FS elements), and the reduction of

residual contaminant concentrations following this removal action (covered by the FS elements).

While the FS elements are discussed in this document, the required Document of Environmental

Protection and Notice of Proposed Action will be separate documents delivered after the removal

action is complete (as required by the UES). Residual remediation (i.e., enhanced



bioremediation, as described in Section 6.0) will be pursued under the non-time critical

mitigation approach after completion of the removal action.

Table 1-1 Document Crosswalk

UES Requirement Section

RAM - §3-6.5.8(g)

(1)(i)

Identify source and nature of contamination

Risk estimation

Extent of threat

Evaluation of factors

2.0

2.1

2.1

1.4, 2.1, 0, 4.3, 4.3.1

(1)(ii)Site background 1.1, 1.2, 1.3

(1)(iii)

EE/CA

SAP

QAPP

HSP

4.0

7.3

7.4

7.5

(1)(iv) Schedule Appendix A

(1)(v) Resource damage restoration 2.2, 4.5, 7.6

(2) Review by Appropriate Agencies Pending

(3) Waste management 7.0

FS - §3-6.5.8(n)

(1) Alternatives assessment 4.0

(2)(i)

Mitigation effectiveness

Technical feasibility

Cost effectiveness

4.0

4.0

4.0

(2)(ii) Proposed plan 3.0, 5.0

(2)(ii)(A) Summary description of remedial alternatives 4.2, 6.0

(2)(ii)(B) Summary of Appropriate Agency comments Pending

(2)(ii)(C) Rationale for preferred alternative 4.3, 4.3.2

(2)(ii)(D) Pertinent cleanup standards 3.0, 4.4, 6.2.1

(2)(iii) Public review and comment Pending

The Site Investigation (SI) performed by Sivuniq in 2010 and 2011 included many of the

components described in 3-6.5.8(g) (as well as those included in 3-6.5.8(k)). Specifically, the SI

included the components defined in 3-6.5.8(g)(1)(i) and (ii), so these components are

summarized here. Additionally, the sampling and analysis plan (SAP), quality assurance project



plan (QAPP), and site safety and health plan (SSHP) were included in the work plan for the SI

and will be adapted for future work at this site; a simplified summary is presented in Section 7.0,

pursuant to 3-6.5.8(g)(iii). Resource damage restoration, as mentioned in 3-6.5.8(g)(1)(v), is

included in the cost estimates provided in Section 4.0.

1.2 PHYSICAL AND ENVIRONMENTAL SETTING

1.2.1 Environmental Setting

Kwajalein Atoll is a coral reef formation in the shape of a crescent loop enclosing a lagoon. The

approximately 100 small islands share a total land area of 5.6 square miles (mi2). The largest

islands are Kwajalein (1.2 mi2), Roi-Namur (0.6 mi

2), and Ebadon at the extremities of the atoll;

together they account for nearly half the total land area. While the “typical” size of the remaining

islands may be about 450 feet by 2,100 feet, the smallest islands are no more than sand cays that

merely break the water's surface at high tide.

The Kwajalein Atoll lagoon enclosed by the reef is the world‟s largest, with a surface area of 902

mi2, and a depth that is generally between 120 to 180 feet (Sugerman, 1972). One notable

characteristic of the atolls is the steep slopes of the mounts seaward of the reef. Around

Kwajalein Atoll, the depth plunges to as much as 6,000 feet within 2 miles of the atoll, and

13,200 feet within 10 miles. Coral atolls are seamounts that have been capped by calcareous

marine growth constructed by lime-secreting organisms (coral polyps and algae). The lower parts

of atolls are composed of noncalcareous rocks, most often volcanic materials. The overlying

coral superstructures may be hundreds or even thousands of feet in thickness. Emergent portions

of the reef and islands tend to be composed of loose, poorly consolidated calcareous materials

derived from foraminifera, coral, shells, and marine algae, or their debris resulting from

destructive action of the elements. All of the islands that comprise the atoll are relatively flat

with few natural points exceeding 15 feet above mean sea level (MSL) (Sugerman, 1972). This

condition presents a major problem for underground construction and allows spilled

contaminants to easily reach the water table.

1.2.2 Climate

Kwajalein‟s tropical marine climate exhibits little variation through the year. The atoll

experiences a relatively dry windy season from mid-December to mid-May, and a relatively wet

calm season from mid-May to mid-December. Normal annual rainfall is approximately 100



inches; approximately 72 percent (%) of the annual rainfall occurs during the wet season and

28% during the dry season. On average, the prevailing wind direction is from the east-northeast

during the entire year, although winds may become more variable during the wet season when

occasional southerly or even westerly winds occur. The average wind speed is approximately 17

miles per hour (mph) from December to April, and 12 mph from May to November.

The average daily maximum temperature is 86.5 degrees Fahrenheit (ºF); the average minimum

temperature is 77.6 ºF. The extreme temperatures recorded at the atoll are 97 ºF and 68 ºF.

Average relative humidity ranges from 83% at local noon to 78% at midnight.

Most of the rainfall at Kwajalein comes from rain showers; thunderstorm occurrences are

infrequent. On average, thunderstorms occur fewer than 12 days each year. The frequency of

thunderstorms ranges from 0.1 per month from January to March to two per month in September.

During the modern era of recordkeeping, since 1919, a fully developed typhoon has never struck

Kwajalein Atoll; however, tropical storms with sustained winds from 40 to 74 mph impact the

atoll on average about once every four to seven years. Rainfall varies significantly across the

atoll with Roi-Namur receiving roughly 60% to 70% of the Kwajalein Island average of

approximately 100 inches per year (ATSC, 2010).

1.2.3 Regional Geology

The detailed geology of Kwajalein Atoll is primarily based on shallow boring logs prepared by

the U.S. Army Corps of Engineers (USACE) and drilling logs prepared during the construction

of monitoring wells by the U.S. Geological Survey (USGS) (Hunt, 1995).

Atolls have been studied intensively since the 1940s, and general models of atoll geology and

hydrology have emerged. Shallow subsurface materials are mainly unconsolidated, reef-derived,

carbonate sediments (sand, gravel, and rubble) with lesser amounts of consolidated rock (coral-

algal boundstone, sandstone, conglomerate, and recrystallized limestone) (Hunt, 1995).

Sediments of different ages are separated by erosional unconformities, which commonly are

marked by soils and leached zones (USGS, 1963).

Studies on Kwajalein Island have shown that the lagoon side of the island consists of

unconsolidated sediments that are thicker and contain a greater proportion of low-permeability

back-reef sand than the ocean side. Drilling logs suggest a greater proportion of coarse, high-



permeability rubble on the ocean side (Hunt, 1995). Conditions are expected to be similar for

Roi-Namur Island.

1.2.4 Soil Characteristics

Soils on Kwajalein Atoll mainly consist of unconsolidated, reef-derived calcium carbonate sand

and gravel with minor consolidated layers of coral, sandstone, and conglomerate. Core samples

and drilling logs at Kwajalein Island indicate mostly unconsolidated carbonate sediments down

to 111.5 feet below ground surface (bgs), with hard layers being more prevalent on the ocean

side of the island (Hunt, 1995); Roi-Namur Island is expected to be of similar composition.

Most of the Roi-Namur Petroleum, Oils, and Lubricants (POL) Yard Spill Site sampling area is

located within post-WWII fill dredged from the reef. The areas south of the perimeter road were

clearly fill material, often saturated with diesel fuel, with the lower portion of the profile

occasionally revealing what appeared to be intact marine sand deposits (Sivuniq, 2011). Soil

samples collected during the Sivuniq SI indicate that the soils are primarily coralline sand, with

some large coral fragments and little finer materials.

1.2.5 Hydrogeology

The thick accumulation of limestone layers, unconformities caused by sea level changes over

time, and tidal activity play an important role in the fresh groundwater dynamics. Groundwater is

very shallow throughout the atoll; a thin freshwater lens lies atop the brackish groundwater on

the largest islands, including Kwajalein and Roi-Namur. Lens thickness is proportional to island

width and rate of groundwater recharge, and inversely proportional to hydraulic conductivity

(Hunt, 1995).

The groundwater lens was identified as thickest near the lagoon (on Kwajalein Island), where

unconsolidated sediments were thickest and contained a greater proportion of low-permeability

back-reef sand. The lens was thinner near the ocean, where drilling logs suggested a greater

proportion of coarse, high-permeability rubble and where core samples of conglomerate were

obtained at a shallower depth than at a more lagoon-ward site (Hunt, 1995).

Groundwater gradients radiate out from groundwater mounds near the center of the islands. The

shallow depth to groundwater and the high permeability of the soils make the groundwater

systems of the Kwajalein Atoll islands highly vulnerable to contamination by chemicals

(USAEHA, 1991).



Studies on Kwajalein Island indicate that aquifer tidal efficiency (i.e. the ratio of feet of tidal

change to feet of change in aquifer water level) increases with depth and proximity to the ocean

and lagoon shores, and is somewhat higher on the ocean side (Hunt, 1995). This included areas

of native soil and areas created with dredge fill.

1.3 SITE DESCRIPTION AND HISTORY

The U.S. Army control of Kwajalein Atoll was established in 1964 after being transferred from

the U.S. Navy. The Navy operated the facility from 1944 to 1964 after the U.S. liberation of the

atoll from the Japanese during WWII. The USAKA/Kwajalein Missile Range (KMR) was

renamed to USAKA/RTS on June 15, 2001.

The naming designations of the installation at Kwajalein Island throughout recent history are as

follows:

USAKA from November 14, 1986 through September 30, 1997;

KMR from April 15, 1968 through November 13, 1986;

Kwajalein Test Site from July 1, 1964 through April 14, 1968;

Navy Operating Base Kwajalein, Naval Air Station Kwajalein, Naval Station

Kwajalein, and Pacific Missile Range Facility (PMRF) Kwajalein at various times

between 1945 and 1964.

The USAKA/RTS is a subordinate activity of the U.S. Army Space and Missile Defense

Command/U.S. Army Forces Strategic Command (SMDC/ARSTRAT), headquartered in

Huntsville, Alabama. Command of the site, with regard to its range mission as an element of the

Department of Defense‟s (DoD) Major Range and Test Facility Base (DoD Directive 3200.11),

is exercised under funding guidance from the U.S. Army Test and Evaluation Office (TEO).

The installation supports the RTS in support of theater missile defense, ballistic missile defense,

and intercontinental ballistic missile (ICBM) testing. Kwajalein also has a missile and space

objects tracking mission utilizing an array of powerful radar dishes located on Roi-Namur Island.

In addition, Kwajalein Island supports other DoD training activities as well as commercial space

launch operations.



1.3.1 Site History

The Roi-Namur POL Yard Spill Site is the fuel storage area for the power plant that

encompasses two diesel fuel aboveground storage tanks (ASTs) (Facilities 8046 and 8047). A

large diesel fuel release of approximately 22,500 gallons occurred at one of the two power plant

ASTs on January 30, 1996. The 350,000-gallon AST #8047 was overfilled because the available

tank volume was erroneously calculated and, due to a faulty level sensing system, the release

was not noticed until the tank was overfilled because the operator apparently left the vicinity

(Raspiller, 1998). At the time of the release, there was no secondary containment around the

POL tanks (although secondary containment has since been added). The fuel release occurred at

the overflow pipe at the base of the tank. Figure 1-1 presents the Roi-Namur POL Yard Spill site.

Emergency response teams recovered approximately 5,640 gallons of released product during the

initial response. An additional 2,888 gallons of product was recovered within the first 24 hours

of the release. Follow up recovery activities (skimming operations from trenches and sumps)

yielded an additional 8,347 gallons of recovery. In total, almost 17,000 gallons, or approximately

75%, of the spill volume was reportedly recovered. Recovery efforts ceased because it was

presumed that at this point, the feasible recovery phase had been achieved (Raspiller, 1998).

Prior to the fuel release, several sites of potential environmental contamination were identified

(USAHEA, 1991). These included an unlined oil/solvent storage pit to the south of the POL

storage tanks, and a wash rack discharge ditch to the north and east of the POL storage tanks

In the 2001 restoration report, it was noted that no humans inhabit the spill site and that no viable

pathways of exposure exist unless construction activities are undertaken at the site (RSE, 2001).

Product removal from the groundwater is reportedly feasible because of the fine- to coarse-

grained calcareous sands, relatively shallow depth to groundwater, predictable tides, and constant

temperatures, which facilitate the remediation process.

1.4 REMOVAL ACTION OBJECTIVE

Per UES 3-6.5.8(g)(3), the scope of the removal action involves the mitigation of contamination

which may pose undue harm or threat prior to the completion of remedial action activities.

Primary considerations are the stability of the wastes and the potential for public contact with the

hazardous materials/wastes. This RAM/FS describes actions to remove/minimize the hazard

indicated by the presence of non-aqueous phase liquid (NAPL) in the subsurface.



The NAPL removal is considered time critical mitigation in this document because it must be

accomplished before contaminant concentrations can be reduced to risk-free levels. Additionally,

the potential for contaminant migration into the lagoon is possible, as detections for multiple

contaminants were found in piezometers installed along the lagoon shoreline. Initiating the time

critical approached described under the RAM/FS process [UES 3-6.5.8(g)] will ensure that this

potential is mitigated in a short timeframe, as well as the potential for human contact if

excavation activities are initiated at the site.



Figure 1-1 Roi-Namur POL Yard Spill Site Overview



2.0 PRE-DESIGN ACTIVITIES TO DATE

2.1 PREVIOUS INVESTIGATIONS

Initial recovery efforts included recovering NAPL product from trenches and sumps, and the

recovery operations continued throughout 1996 primarily at one of the trenches where the

majority of the NAPL had accumulated. In addition to the trenches, four wells were installed

with skimmers to recover product. One of the wells continued to operate until March 1997, when

recovery operations ceased because it was presumed that at this point, the feasible recovery

phase had been achieved (Raspiller, 1998).

Historical contamination from previous activities at the site (the unlined oil/solvent pit, leaks

from fuel storage and associated piping, and/or the wash rack discharge ditch) became apparent

during the recovery operations because of weathered product that was being recovered. The 2001

RSE report indicates pipeline monitoring during transfer operations was conducted because of

previous leaks that had occurred that required rapid response to keep the product from entering

the lagoon. Also, this report suggests it was common practice to dispose of engine crank oil,

solvents, contaminated fuel, and petroleum sludge in an unlined pit adjacent to the site of the

1996 diesel fuel oil spill (RSE, 2001).

Prior to the spill, a study was conducted to preliminarily characterize potential contamination

associated with the oil/solvent pit and the wash rack discharge ditch (USAHEA, 1991). Aroclor

1260 and lead were identified as contaminants at the wash rack discharge ditch to the north of

the POL storage tanks. A monitoring well downgradient of the tanks (that has since been

removed) identified the presence of groundwater contamination by fuel oil, including NAPL

floating on the water table. 1,1-dichloroethane (DCE), naphthalene, and n-butyl-benzene were

detected at low levels (micrograms per liter [µg/L] range), while hydrocarbons were detected at

milligrams per liter (mg/L) levels. It was noted that a portion of the subsurface hydrocarbon

contamination at the site might have been due to a release of fuel from either the tanks or

associated piping, and not the oil/solvent pit. Additionally, human risk was not evaluated from

these results because the only identified risk pathway was due to excavation work at the site

(which was not expected to be performed). Since the scope of the study was limited, it is

uncertain how widespread POL and solvent contamination were prior to the 1996 spill.



An additional study conducted in 1991 references a limited SI at a power plant burn pit located

on Roi-Namur Island (ORNL, 1991). Although the report is ambiguous to the exact location of

this burn pit, it can be reasonably concluded that it was an investigation of the oil/solvent pit

mentioned above. From the limited data collected during this effort, the report concluded that the

power plant burn pit was contaminated by petroleum hydrocarbons (at milligrams per kilogram

[mg/kg] levels) and, to a lesser extent, lighter weight organics including some chlorinated

solvents (at micrograms per kilogram [µg/kg] levels). Total petroleum hydrocarbons were

present in the range of 5000 mg/kg near the pit and at appreciable but lower levels (500 mg/kg),

approximately 100 feet away and near the lagoon. These conclusions agree with the study

mentioned above.

The amount of fuel recovered from the 1996 spill was significantly less than the amount

suspected of being spilled. Since soil and groundwater were known to be contaminated, a follow-

up SI was conducted by Sivuniq in 2010 and 2011 to evaluate the nature and extent of remaining

contamination in the vicinity of the Roi-Namur POL Yard Spill Site (Sivuniq, 2011). The

investigation, which included soil (Figure 2-1) and groundwater (Figure 2-2) sampling, revealed

that soil and groundwater contamination remains at the site, including over a foot of emulsified

NAPL on the groundwater surface in the most contaminated area (Figure 2-3). Contaminants

were also identified in piezometers at concentrations below screening levels that were installed

on the beach, indicating that that future monitoring should be performed to determine the extent

of the impact to the lagoon. The primary contaminant in soil and groundwater was diesel range

organics (DRO), although concentrations of gasoline range organics (GRO), benzo(a)anthracene,

naphthalene, and phenanthrene exceeded applicable screening criteria in soil. The frequency and

range of detected compounds are presented in Table 2-1. Sampling near the former wash rack

discharge ditch did not identify unique contaminants; sampling was not conducted near the

former unlined oil/solvent pit as that area was presumed to be contaminated and the focus of the

investigation was on delineation. Samples were also taken for bioremediation and physical

parameters. These are discussed as part of the engineering analysis in Section 4.0.

Isolated oil-contaminated soil was identified around a soil boring to the northern extent of the

investigation (SB63) (Figure 2-1) and is likely a separate source of contamination since it is one

of the few soil borings that was located within the border of the original island shoreline.



Although DRO contamination was detected in this boring, it is likely bleed-over from residual

range organics contamination (i.e. oil). The source of this contamination is likely associated with

activities during or shortly after WWII, although this cannot be definitely concluded until further

data is collected.

Contaminant plumes were defined in soil and groundwater using DRO concentrations (Figure

2-4). The extent of contamination was delineated except to the southwest, where high screening

results and analytical detections indicate that a plume of lighter-weight, volatile contaminants

may have migrated in that direction (beyond the extent of the DRO plume). Clean analytical and

screening results bounded the contaminant plume in all other directions.



Table 2-1 Frequency and Magnitude of Compounds Detected During the 2010/11 SI

Soil

Analyte Frequency Range (mg/kg) Average

(mg/kg)

UCL 95

(mg/kg)

Screening

Criteria

(mg/kg)

2-Methylnaphthalene 25 / 64 0.00176 - 64 7.812 5.316 3101

Acenaphthene 26 / 64 0.00114 - 11.6 1.146 0.812 34001

Acenaphthylene 20 / 64 0.00116 - 2.04 0.4 0.2 12.722

Anthracene 28 / 64 0.00179 - 4.62 0.631 0.434 17000

Benzene 2 / 45 0.00251 - 0.0419 0.0222 0.00538 1.11

Benzo (a) anthracene 5 / 64 0.0071 - 0.137 0.0534 0.0158 0.151

Benzo (a) pyrene 1 / 64 0.00325 0.00325 NC 0.0151

Benzo (b) fluoranthene 1 / 64 0.0109 0.0109 NC 0.151

Chrysene 4 / 64 0.00373 - 0.196 0.0582 0.0134 151

DRO 46 / 66 5.94 – 52,400 5,432 5,750 5002

Ethylbenzene 4 / 45 0.128 - 2.36 0.987 0.194 5.41

Fluoranthene 15 / 64 0.00194 - 1.26 0.211 0.0905 23001

Fluorene 25 / 64 0.00159 - 13.2 1.491 1.013 23001

GRO 17 / 66 0.0187 - 261 29.3 14.78 1002

Naphthalene 19 / 64 0.0014 - 15.7 2.115 1.124 3.61

Phenanthrene 27 / 64 0.00178 - 25.6 1.833 1.462 10.692

Pyrene 17 / 64 0.00197 - 2.37 0.359 0.172 17001

Toluene 1 / 45 0.00123 0.00123 NC 50001

Xylenes (combined) 3 / 45 0.18 - 1.147 0.594 0.251 6301

Groundwater

Analyte Frequency Range (µg/L) Average

(µg/L)

UCL 95

(µg/L)

Screening

Criteria (µg/L)

1,2,4-Trimethylbenzene 1 / 11 0.18 0.18 NC 153

Benzene 2 / 11 0.07 - 0.16 0.115 0.0982 54

Carbon disulfide 4 / 11 1.28 - 3.56 2.255 2.076 10003

DRO 3 / 11 37.8 – 3,510 1,932.6 1,310 6402

Isopropylbenzene 1 / 11 0.46 0.46 NC -

Naphthalene 1 / 11 0.37 0.37 NC 242

n-Butylbenzene 1 / 11 0.48 0.48 NC 18003

n-Propylbenzene 1 / 11 0.53 0.53 NC -

sec-Butylbenzene 1 / 11 0.6 0.6 NC -

Tetrachloroethene 1 / 11 0.16 0.16 NC 54

Toluene 1 / 11 0.51 0.51 NC 10004

Xylenes (combined) 1 / 11 0.42 0.42 NC 100004

Notes, Acronyms and Abbreviations: 1Screening levels based on EPA residential RSLs. 2Screening levels based on GEPA ESLs (unrestricted land-use with a nonpotable water source and shallow contamination). 3 Screening levels based on EPA PRGs for tap water; since the water

source is nonpotable, this conservatively biases the results. 4Screening levels based on UES Table 3-2D.1. Analytes identified as COCs are

bolded. NC = not calculated; UCL = upper confidence limit.



Figure 2-1 Roi-Namur POL Yard Soil Boring Locations and Analytical Detections



Figure 2-2 Roi-Namur POL Yard Piezometer Locations and Analytical Detections



Figure 2-3 Roi-Namur POL Yard Product Thickness Map



Figure 2-4 Roi-Namur POL Yard DRO Plume in Groundwater



2.1.1 Conceptual Site Model

Based on historical information and data collected by the latest SI, Table 2-2 summarizes the

conceptual site model (CSM) for the Roi-Namur POL Yard Spill Site.

Table 2-2 Roi-Namur Plan Spill Site CSM

Model Element Input Rationale

Primary Source Petroleum separate phase hydrocarbons,

solvents Documented sources

Primary Transport

Mechanism

Direct separate phase hydrocarbons

discharge

Release from storage tanks and abandoned

pipeline, wash rack discharge ditch, and

oil/solvent pit

Secondary Source Contaminated soil Contamination from direct discharge

Secondary Transport

Mechanisms

Separate phase hydrocarbons migration

from the release point(s)

Dissolved (aqueous) transport by

groundwater

Measured and reported soil contamination at

various locations

Measured groundwater contamination in vicinity

of release locations

Exposure Media Soil

Groundwater

Contamination in soil

Contamination in groundwater

Exposure Pathways

Incidental ingestion of soil

Dermal contact with soil

Inhalation of vapors

Direct contact and use at site locations

Current Receptors On-site operations personnel

On-site (construction) workers

USAKA and contractor personnel are potentially

exposed during excavation work at site locations

Future Receptors On-site residents Unrestricted future land-use and development.

Complete/Significant

Exposure Scenarios

Incidental soil ingestion and dermal contact with contaminated soil by future on-site workers

during excavation activities.

Inhalation of soil contaminant vapors by future on-site workers and future operations

personnel.

Exposure scenarios for future residents cannot be evaluated at this time due to lack of surface

soil analytical data.

Note that although groundwater contamination was encountered, groundwater from the most

contaminated area is not within the freshwater lens and will therefore not be used as potable

water. This was based on freshwater lens maps (see Figure 2-5), and also on conductivity

measurements (more dissolved ions [i.e. salts] would give a higher conductivity reading) and

results for the amount of chloride ions present in sampled groundwater (Sivuniq, 2011). The

freshwaters lens maps indicated that freshwater was unlikely to be located south (also

downgradient) of the diesel storage ASTs, and that groundwater would flow out towards the

lagoon (effectively flushing contamination out of the tip of the freshwater lens that might be

present north of the ASTs); this is compounded by the fact that the ASTs (and surrounding area)

are located on artificial land created by coral dredging (see Figure 2-5), further making extensive

freshwater reserves in the area unlikely.



Therefore, the following exposure pathways were ruled out: ingestion of groundwater, contact

with groundwater, and inhalation of groundwater vapors (which would likely be the result of

water heating activities, like showers). This concurs with a prior preliminary characterization

performed in 1991, which concluded that this site is not located within the area in which usable

quantities of fresh groundwater exist, and that there is no direct human exposure pathway via

groundwater (USAHEA, 1991).

Complete/significant exposure scenarios related to each receptor are as follows:

On-site operations personnel:

o Inhalation of soil contaminant vapors from proximity to any open excavations at

the site

On-site construction workers:

o Incidental ingestion of soil and dermal contact with soil from direct exposure due

to construction activities at the site

o Inhalation of soil contaminant vapors from proximity to any open excavations at

the site

Note that residents are not included as part of the risk scenarios, because the risk from current

residents incidentally contacting contaminated material are accounted for from the

aforementioned receptors. However, screening levels used to determine contaminants to be

evaluated as part of the risk assessment have used residential or unrestricted land-use scenarios

to encompass risk due to potential residential exposure.

Additionally, future residents have been added to the CSM to account for Marshallese citizens

after the lands are turned over to the Republic of the Marshall Islands (RMI). Note that although

this pathway was not initially identified in the work plan, it has been included here for

completeness. While it is assumed that surface soil (0 to 2 feet bgs) contamination is not present

at the site due to presumed spill response activities, potential exposure cannot be definitely

excluded because no data was collected for evaluation. Collection of surface soil data is planned

as part of a supplemental mobilization for the aforementioned SI (see Section 5.0).



2.2 CULTURAL RESOURCE ASSESSMENT

Archaeological monitoring of soil from all sampling locations is discussed and presented in the

Roi-Namur POL Yard SI (Sivuniq, 2011). In summary, no artifacts or discrete cultural features

were uncovered during the SI.



Figure 2-5 Roi-Namur Island Freshwater Lens and Dredge Fill Map



3.0 APPLICABLE REMEDIAL TECHNOLOGIES

3.1 SCOPE AND PURPOSE OF REMOVAL ACTION

The scope of removal and remedial actions at the Roi-Namur POL Yard Spill Site includes soil

and groundwater contamination from the 1996 fuel spill, as well as contamination from

historically identified sources that exceed cleanup concentrations (as defined below). The

objection of the removal action is to remove contaminants from the soil and restore groundwater

quality so that cleanup concentrations are achieved.

After delineation of the remaining contamination in the Roi-Namur POL Yard Spill Site area, it

was determined that the highest concentration of contaminants of concern (COCs) were centered

around the tanks, with the groundwater contamination plume extending into the lagoon and

covering an area of approximately 216,500 square feet. This plume was defined by the

concentration equal to or greater than 640 µg/L of DRO (the primary COC) (which is the

environmental screening level [ESL] provided by the Guam Environmental Protection Agency

[GEPA] for a residential site with shallow contamination over a non-potable water source).

The area covering where measurable quantities of NAPL exist is approximately 150,000 square

feet (Figure 2-3). Soil contamination is primarily located in the vadose zone soils, and is

encompassed by the area covered by the groundwater contamination plume. GRO,

benzo(a)anthracene, benzo(a)pyrene, naphthalene, and phenanthrene are also COCs at this site.

The purpose of remedial actions is to lower the concentrations of these COCs to acceptable

exposure levels [per UES 3-6.5.8(l)(3)] in groundwater as identified by comparison to GEPA

ESLs, U.S. Environmental Protection Agency (EPA) Regional Screening Levels (RSLs), or

National Oceanic and Atmospheric Administration (NOAA) Screening Quick Reference Tables

(SQuiRTs), and contaminants in soil as identified by comparison to EPA RSLs or GEPA ESLs,

pursuant to UES 3-6.5.8(l)(2).

The UES regulatory framework identifies the area around the Roi-Namur POL Yard as

containing „Class III‟ groundwater. Additionally, the contamination does not extend into

adjacent „Class I‟ groundwater, and is not likely to impact the water quality of that groundwater

since it is downgradient. Therefore, according to UES 3-2.6.2, the water does not have to follow



the standards presented in UES Appendix 3-2D, and risk-based cleanup levels will be used as

described above; this rationale is pursuant to UES 3-6.5.8(n)(2)(ii)(D).

The practicability of any remediation option depends on factors related to the type of

contamination, site characteristics, cost, and performance. Remediation options were assessed

using the Treatment Technologies Screening Tool developed by the Federal Remediation

Technologies Roundtable (FRTR) (USACE, 2002). The FRTR is an interagency work group that

exchanges information between government agencies responsible for remediation of

environmental sites. The screening tool grades remediation technologies on criteria such as cost,

performance and logistical requirements. This information is continually updated in response to

new technology.

Technologies were selected from the FRTR Screening Matrix primarily based on the ability to

remediate DRO and GRO („Fuels‟ in the screening matrix), although secondary consideration

was given to the ability to remediate nonhalogenated semivolatile organic compounds (SVOCs)

(for benzo(a)anthracene, benzo(a)pyrene, naphthalene, and phenanthrene). Technologies that

were considered above average for these two contaminant groups were then researched further

before the final few technologies were selected for in-depth analysis (described below).

Since NAPL remains floating on the groundwater over a large area of the Roi-Namur POL Yard

Spill Site, a treatment train is necessary so that available remedial options can be implemented

after this NAPL is removed. Remedial technologies were selected with this in consideration as

well.

The affected area of this removal action is approximate, and will be more precisely defined by

additional soil and groundwater data before the removal action is implemented. These actions are

proposed and described in Section 5.0.

3.2 JUSTIFICATION FOR THE PROPOSED ACTION

Sampling of soils and groundwater during the SI and historical information show contamination

remains from multiple sources at the Roi-Namur POL Yard Spill Site. COCs identified for the

site include DRO, GRO, benzo(a)anthracene, benzo(a)pyrene, naphthalene, and phenanthrene for

soil, and DRO for groundwater; these contaminants exceed 10% of their applicable screening



levels. Over a foot of emulsified NAPL is also present on the water table, and exceedances were

identified in soil and groundwater for DRO, and in soil for GRO, naphthalene, and phenanthrene

(Sivuniq, 2011).

Additionally, bioremediation parameters were collected from the affected area to determine if

active bioremediation (natural attenuation) was occurring at the site. Although many results were

qualified as estimated due to holding time exceedances, the data indicates that little active

bioremediation is taking place and that nutrients have been exhausted where natural attenuation

was taking place. This means that the concentrations of contaminants at the site will degrade

very slowly, and that human action is necessary for the site to return to its natural state in the

foreseeable future.

Potential remedial technologies pursuant to the scope and of this removal action are described in

the following sections.

3.3 TECHNOLOGY IDENTIFICATION AND DESCRIPTION

Preliminary technologies provided by the FRTR Screening Matrix are presented in Table 3-1.

These options were selected from all available choices based on having above average

performance for both „Fuels‟ and „Nonhalogenated SVOCs‟.



Table 3-1 FRTR Screening Matrix Preferred Options

Black = Above Average

Gray = Average

White = Below Average

Red = Level of Effectiveness highly dependent

upon specific contaminant and its application

N/A = "Not Applicable"

I/D = "Insufficient Data"

Dev

elo

pm

ent

Sta

tus

Tre

atm

ent

Tra

in

Relative Overall Cost &

Performance

Contaminant

Groups

O&

M

Ca

pit

al

Sy

stem

Rel

iab

ilit

y

& M

ain

tain

ab

ilit

y

Rel

ati

ve

Co

sts

Tim

e

Av

ail

ab

ilit

y

No

nh

alo

gen

ate

d

SV

OC

's

Fu

els

Soil, Sediment, Bedrock and Sludge

In situ Biological Treatment

Bioventing

Enhanced Bioremediation

In situ Thermal Treatment

Thermal Treatment

Ex Situ Biological Treatment (assuming

excavation)

Landfarming

Slurry Phase Biological Treatment

Ex situ Thermal Treatment (assuming

excavation)

Incineration

Thermal Desorption

Ground Water, Surface Water, and Leachate

In situ Biological Treatment

Enhanced Bioremediation

In situ Physical/Chemical Treatment

Bioslurping

Dual Phase Extraction

Thermal Treatment

Ex situ Biological Treatment (assuming

excavation)

Bioreactors

Ex situ Physical/Chemical Treatment (assuming

pumping)

Advanced Oxidation Processes

Granulated Activated Carbon/ Liquid Phase

Adsorption

Separation

Containment

Physical Barriers

Air Emissions/ off-Gas Treatment

Oxidation N/A I/D

Vapor Phase Carbon Adsorption N/A I/D

Notes: Adapted from FRTR, 2007



From the above options, those involving excavation were discounted as not applicable. This is

because the affected area for treatment is approximately 150,000 square feet for NAPL removal,

and 216,500 square feet for remediation of residual contamination; additionally, the affected soil

and groundwater is covered with up to approximately four feet of presumably clean overburden.

This meant that all ex situ technologies for soil were excluded (except for NAPL removal by

infiltration galleries, which would excavate a comparably small amount of soil from installation

of collection trenches), as well as groundwater treatment by bioreactors.

Similarly, those technologies involving extensive pumping were excluded due to UES

restrictions on Class I groundwater, which is adjacent to the site. Since the area of contamination

is directly downgradient of Class I groundwater, extensive groundwater pumping would likely

start to drain the aquifer used to supply potable water for much of Roi-Namur Island; Class I

groundwater cannot be affected in this manner if water quality is affected, according to UES

regulations. If the treated groundwater could be reintroduced as reclaimed water, it could be used

to resupply the freshwater lens; however, as the groundwater contains considerable

concentrations of contaminations, this option is likely not feasible and has been discounted.

Additionally, containment by physical barriers was discounted because of the size of the affected

area and also because the plume extends to the lagoon shoreline (which would complicate

containment efforts significantly). Based on the assumed hydraulic gradient, groundwater

movement is likely very slow, meaning that physical containment would not provide enough

benefit to be practical for implementation.

The following options were selected for evaluation and analysis after all options were

researched:

NAPL Removal

o Bioslurping (which would include off-gas treatment and ex situ groundwater

treatment)

o Dual phase extraction (which would include off-gas treatment and ex situ

groundwater treatment)

o Infiltration galleries (which would include ex situ soil treatment for excavated soil

and ex situ groundwater treatment)



Soil and Groundwater Remediation

o Enhanced bioremediation

o Thermal treatment

Note that infiltration galleries are not present in the FRTR Screening Matrix options identified

above. It is essentially an ex situ groundwater treatment, although it is still being considered

because the amount of groundwater removed is significantly less than other ex situ groundwater

treatment technologies (because its primary mode of operation is skimming).

Depending on success of NAPL removal, monitored natural attenuation may also be considered.

However, this will not be analyzed as a viable option at this time because bioremediation

parameters results indicate that natural attenuation has occurred but is now nutrient and oxygen

limited (see Section 4.2.1); if NAPL removal is adequately successful, this will be considered at

that time.

Since NAPL still remains onsite, a NAPL removal system will need to be implemented before

other remedial technologies can be utilized. All applicable technologies are described below, and

categorized by NAPL removal options and remedial options. These technologies are evaluated in

Section 4.0.

3.3.1 NAPL Removal Options

The main principle behind the removal of NAPL at the Roi-Namur POL Yard Spill Site is to

capture emulsified product floating in the upper margin of the groundwater. Four general

techniques or approaches are used to recover NAPL (EPA, 1996):

NAPL removal/skimming systems

NAPL recovery with water table depression

Vapor extraction/groundwater extraction

Dual phase (liquid and vapor) recovery

NAPL recovery with water table depression was discounted due to UES restrictions on Class I

groundwater, as described above. The technologies utilizing the other techniques were selected

primarily from the FRTR Screening Matrix, and are described below.



3.3.1.1 Dual Phase Extraction

Dual phase extraction (DPE), also known as multi-phase extraction or vacuum-enhanced

extraction, is a technology that uses a vacuum system to remove various combinations of

contaminated groundwater, separate-phase petroleum liquid, and hydrocarbon vapor from the

subsurface using a multi-pump system. Extracted liquids and vapor are treated and collected

separately for disposal, or re-injected to the subsurface (FRTR, 2007). It is very similar to

bioslurping, which is discussed in Section 3.3.1.2.

DPE systems can be effective in removing separate-phase liquids from the subsurface, thereby

reducing concentrations of petroleum hydrocarbons in both the saturated and unsaturated zones

of the subsurface. DPE systems are typically designed to maximize extraction rates; however, the

technology also stimulates biodegradation of petroleum constituents in the unsaturated zone by

increasing the supply of oxygen due to pore-space vapor cycling with air from the surface, and

the general system design is amenable to implementation of bioventing or biosparging (EPA,

1995).

A vacuum system is utilized to remove liquid and gas from low permeability or heterogeneous

formations. The vacuum extraction well includes a screened section in the zone of contaminated

soils and groundwater. It removes contaminants from above and below the water table. The

system lowers the water table around the well, exposing more of the formation. Contaminants in

the newly exposed vadose zone are then accessible to vapor extraction. Once above ground, the

extracted vapors or liquid-phase organics and groundwater are separated and treated. Dual phase

extraction for liquid/vapor treatment is generally combined with bioremediation, biosparging, or

bioventing when the target contaminants include long-chained hydrocarbons (FRTR, 2007).

Although the technology is generally described above, significant variations in design for DPE

systems exist. DPE systems often apply relatively high vacuums to the subsurface. Thus, the

adjective “high-vacuum” is sometimes used to describe DPE technologies, even though all DPE

systems are not high-vacuum systems. The most noteworthy system variation is the use of a

single pump or multiple pumps for extraction. Single pump designs are known as bioslurping,

while multi-pump designs are known as DPE (EPA, 1995).



Multi-pump systems use one pump to extract liquids from the well and a surface blower (the

second pump) to extract soil vapor. An additional pump is sometimes used to specifically extract

floating product on the groundwater surface. Multi-pump systems are simply a combination of

traditional soil vapor extraction and groundwater (and/or floating product) recovery systems.

Multi-pump systems tend to be more flexible than single-pump systems, making them easier to

apply over a wider range of site conditions (e.g., fluctuating water tables, wide permeability

ranges); however, equipment costs are higher (EPA, 1995).

The target contaminant groups for dual phase extraction are volatile organic compounds (VOCs)

and fuels (e.g., light non-aqueous-phase liquids [LNAPLs]). Dual phase vacuum extraction is

more effective than soil vapor extraction for heterogeneous clays and fine sands. However, it is

not recommended for lower permeability formations due to the potential to leave isolated lenses

of un-dissolved product in the formation (FRTR, 2007).

The vacuum applied to the subsurface with DPE systems creates vapor-phase pressure gradients

toward the vacuum well. These vapor-phase pressure gradients are also transmitted directly to

the subsurface liquids present, and those liquids existing in a continuous phase will flow toward

the vacuum well in response to the imposed gradients. The higher the vacuum, the larger the

hydraulic gradients that can be achieved in both vapor and liquid phases, and thus greater vapor

and liquid recovery rates (EPA, 1995).

Dramatic enhancements in both water and petroleum product recovery rates resulting from the

large hydraulic gradients attainable with DPE systems have been reported (EPA, 1995). The

depressed groundwater table that results from theses high recovery rates serves both to

hydraulically control groundwater migration and to increase the efficiency of vapor extraction.

A flow diagram for DPE is presented in Figure 3-1.



Figure 3-1 Flow Diagram for DPE

3.3.1.2 Bioslurping

Bioslurping utilizes vacuum-enhanced free NAPL recovery in process very similar to DPE. The

primary difference between bioslurping and DPE is that bioslurping uses a single pump design,

while DPE uses a multi-pump design. Vacuum-enhanced free-product recovery extracts

LNAPLs from the capillary fringe and the water table. Bioslurping combines elements of both

technologies to simultaneously recover NAPL and bioremediate vadose zone soils (FRTR,

2007).

The single pump system utilized by bioslurping relies on high-velocity airflow to lift suspended

liquid droplets upward by frictional drag through an extraction tube to the ground surface. This

technology can be used to extract groundwater combinations of separate-phase product and

groundwater. Bioslurping is generally better suited to low-permeability conditions than DPE,

although they are difficult to implement at sites where natural fluctuations in groundwater levels

are substantial (EPA, 1995).

Bioslurping can improve free-product recovery efficiency without extracting large quantities of

groundwater. In bioslurping, vacuum-enhanced pumping allows LNAPL to be lifted off the

Groundwater and Product Extraction

Groundwater/Product Separator

Product Storage

Groundwater Treatment

Soil Vapor Extraction Air Emission Off-Gas

Treatment



water table and released from the capillary fringe. This minimizes changes in the water table

elevation which minimizes the creation of a smear zone. Bioventing of vadose zone soils is

achieved by drawing air into the soil due to withdrawing soil gas via the recovery well. The

system is designed to minimize environmental discharge of groundwater and soil gas. When

free-product removal activities are completed, the bioslurping system is easily converted to a

conventional bioventing or biosparging system to complete the remediation via enhanced

bioremediation. The system is otherwise similar to DPE, as described in Section 3.3.1.1.

A flow diagram for bioslurping is presented in Figure 3-2.

Figure 3-2 Bioslurping Flow Diagram

3.3.1.3 Infiltration Gallery Collection

Infiltration gallery collection is a fairly straightforward method of NAPL removal. Extraction

trenches are dug below the surface of the water table, and stabilized with porous sidewalls that

allow the upper layer of groundwater (which will include the NAPL) to collect in the trenches.

Skimmers and/or sump pumps are then used to collect groundwater and NAPL, which is treated

using an ex situ treatment technology after being separated. Further percolation of NAPL and

groundwater through the porous sidewalls due to passive diffusion and rainwater infiltration

allows further product to be recovered and treated.

Sumultaneous Gas and Liquid Extraction

Aboveground Phase Separator

Air Emission Off-Gas Treatment

Groundwater/Product Separator

Product Storage

Groundwater Treatment



Soil removed to install the trenches will need to be segregated into clean overburden and

contaminated soil. Contaminated soil must be treated using an ex situ treatment technology,

which is typically landfarming (since it is the simplest to implement). Clean overburden will be

stockpiled near the site and used as clean fill once NAPL removal is complete. Treated soil will

also be used as fill once NAPL removal is complete.

Infiltration galleries are essentially an ex situ groundwater treatment technology, but allows a

specific strata of groundwater to be targeted for treatment. Since the NAPL present at the Roi-

Namur POL Yard Spill Site is a LNAPL, it can be skimmed or pumped off of the surface with

little residual groundwater collection, especially if hydrophobic collection materials are used to

segregate product. This will provide less drawdown from surrounding groundwater, and will also

allow the most affected groundwater to be drawn into the trenches (less mixing will occur). The

overall goal is the collection of NAPL with little recovery of groundwater.

3.3.2 Remedial Options

The main principle behind the remedial options is to reduce residual concentrations left from the

NAPL removal action to levels where no risk remains to potential receptors. Due to site-specific

constraints, only two options are presented below.

3.3.2.1 Enhanced Bioremediation

Enhanced bioremediation technologies are used to accelerate naturally occurring in situ

bioremediation of petroleum hydrocarbons, and some fuel oxygenates, primarily by indigenous

microorganisms in the subsurface. Most of these technologies work by providing a supplemental

supply of oxygen to the subsurface (although other nutrients can also be supplemented), which

becomes available to aerobic, hydrocarbon-degrading bacteria. The stoichiometric ratio of

oxygen per hydrocarbon is 3 moles oxygen gas (O2) per 1 mole of hydrocarbons. Oxygen is

considered by many to be the primary growth-limiting factor for hydrocarbon-degrading

bacteria, but it is normally depleted in zones that have been contaminated with hydrocarbons. By

using these technologies, rates of biodegradation of petroleum hydrocarbons can be increased at

least one, and sometimes several, orders of magnitude over naturally-occurring, non-stimulated

rates (EPA, 2004).



Most enhanced bioremediation technologies primarily address petroleum hydrocarbons

(typically, mid-weight petroleum products like diesel fuel) and some oxygenates that are

dissolved in groundwater or are sorbed to soil particles in the saturated zone. The technologies

are typically employed outside heavily contaminated source areas which will usually be

addressed by more aggressive remedial approaches. It is generally not practical to use this

technology to address free mobile product or petroleum contamination in low permeability soil

(EPA, 2004).

Enhanced bioremediation may be classified as a long-term technology which may take several

years for cleanup of a plume. It is discussed for each matrix separately in the following sections.

3.3.2.1.1 Soil

The activity of naturally occurring microbes is stimulated by circulating water-based solutions

through contaminated soils to enhance in situ biological degradation of organic contaminants or

immobilization of inorganic contaminants. Nutrients, oxygen, or other amendments may be used

to enhance bioremediation and contaminant desorption from subsurface materials (FRTR, 2007).

In the presence of sufficient oxygen (aerobic conditions), and other nutrient elements,

microorganisms will ultimately convert many organic contaminants to carbon dioxide, water,

and microbial cell mass. Enhanced bioremediation of soil typically involves the percolation or

injection of groundwater or uncontaminated water mixed with nutrients and saturated with

dissolved oxygen (DO). Oxygen is typically supplied via oxygen releasing compounds, hydrogen

peroxide infiltration, pure oxygen injection, ozone injection, or bioventing. Sometimes

acclimated microorganisms (bioaugmentation) are also added. An infiltration gallery or spray

irrigation is typically used for shallow contaminated soils, and injection wells are used for deeper

contaminated soils.

Aerobic conditions in soil can be enhanced using bioventing, which uses low airflow rates to

provide only enough oxygen to sustain microbial activity. Oxygen is most commonly supplied

through direct air injection into residual contamination in soil. In addition to degradation of

adsorbed fuel residuals, volatile compounds are biodegraded as vapors move slowly through

biologically active soil.



In the absence of oxygen (anaerobic conditions), the organic contaminants will be ultimately

metabolized to methane, limited amounts of carbon dioxide, and trace amounts of hydrogen gas.

Under sulfate-reduction conditions, sulfate is converted to sulfide or elemental sulfur, and under

nitrate-reduction conditions, nitrogen gas is ultimately produced (FRTR, 2007).

3.3.2.1.2 Groundwater

The rate of bioremediation of organic contaminants by microbes is enhanced by increasing the

concentration of electron acceptors and nutrients in groundwater. Oxygen is the main electron

acceptor for aerobic bioremediation. Nitrate and sulfate serve as alternative electron acceptors

under anaerobic conditions.

Biosparging (akin to bioventing, but below the vadose zone; also called air sparging) below the

water table increases groundwater oxygen concentration and enhances the rate of biological

degradation of organic contaminants by naturally occurring microbes. Biosparging also increases

mixing in the saturated zone, which increases the contact between groundwater and soil. The

ease and relatively low cost of installing small-diameter air injection points allows considerable

flexibility in the design and construction of a remediation system (EPA, 2004).

Oxygen releasing compounds, hydrogen peroxide infiltration, pure oxygen injection, and ozone

injection can also be used to stimulate an aerobic environment. During these activities, a dilute

solution is circulated through the contaminated groundwater zone to increase the oxygen content

of groundwater and enhance the rate of aerobic biodegradation of organic contaminants by

naturally occurring microbes.

In nitrogen-limited environments, nitrate can be circulated to increase anaerobic biodegradation.

Solubilized nitrate is circulated throughout groundwater contamination zones to provide an

alternative electron acceptor for biological activity and enhance the rate of degradation of

organic contaminants. This technology enhances the anaerobic biodegradation through the

addition of nitrate (FRTR, 2007).

3.3.2.2 Thermal Treatment

Thermal treatment is discussed for each matrix separately in the following sections.



3.3.2.2.1 Soil

Thermally enhanced soil vapor extraction (SVE) is a full-scale technology that uses electrical

resistance/electromagnetic/fiber, optic/radio frequency heating, or hot-air/steam injection to

increase the volatilization rate of semi-volatiles and facilitate extraction. The process is

otherwise similar to standard SVE, but requires heat resistant extraction wells (FRTR, 2007).

Electrical resistance heating uses an electrical current to heat less permeable soils so that water

and contaminants trapped in these relatively conductive regions are vaporized and ready for

vacuum extraction. Electrodes are placed directly into the less permeable soil matrix and

activated so that electrical current passes through the soil, creating a resistance which then heats

the soil. The heat dries out the soil causing it to fracture. These fractures make the soil more

permeable allowing the use of SVE to remove the contaminants. The heat created by electrical

resistance heating also forces trapped liquids to vaporize and move to the steam zone for removal

by SVE (FRTR, 2007).

Radio frequency heating (RFH) is an in situ process that uses electromagnetic energy to heat soil

and enhance SVE. RFH technique heats a discrete volume of soil using rows of vertical

electrodes embedded in soil (or other media). Heated soil volumes are bounded by two rows of

ground electrodes with energy applied to a third row midway between the ground rows. The

three rows act as a buried triplate capacitor. When energy is applied to the electrode array,

heating begins at the top center and proceeds vertically downward and laterally outward through

the soil volume. The technique can heat soils to over 300 degrees Celsius (°C).

RFH enhances SVE in four ways: (1) contaminant vapor pressure and diffusivity are increased

by heating, (2) the soil permeability is increased by drying, (3) an increase in the volatility of the

contaminant from in situ steam stripping by the water vapor; and, (4) a decrease in the viscosity

which improves mobility. The technology is self limiting; as the soil heats and dries, current will

stop flowing. Extracted vapor can then be treated by a variety of existing technologies, such as

granular activated carbon or incineration.

In hot air or steam injection, hot air or steam (or water) is injected below the contaminated zone

to heat up contaminated soil. The heating enhances the release of contaminants from the soil



matrix in the same manner as RFH. Some VOCs and SVOCs are stripped from contaminated

zone and brought to the surface through SVE.

Thermally enhanced SVE is normally a short- to medium-term technology (FRTR, 2007).

3.3.2.2.2 Groundwater

Steam is forced into an aquifer through injection wells to vaporize volatile and semivolatile

contaminants. Vaporized components rise to the unsaturated (vadose) zone where they are

removed by vacuum extraction and then treated. In situ biological treatment may follow the

displacement and is continued until ground water contaminants concentrations satisfy statutory

requirements (FRTR, 2007).

The process can be used to remove large portions of oily waste accumulations and to retard

downward and lateral migration of organic contaminants. The process is applicable to areas with

shallow and deep contamination, and readily available mobile equipment can be used.

Hot water/steam injection is typically short to medium duration, lasting a few weeks to several

months.



4.0 ENGINEERING EVAULATION AND COST ANALYSIS OF

ALTERNATIVES

Each technology described above was analyzed for effectiveness, implementability, and cost, as

prescribed by UES 3-6.5.8(g)(1)(iii) for RAMs/FSs. Each technology was categorized into

NAPL removal options and remedial options. Technologies were evaluated according to UES 3-

6.5.8(n)(1) and (2).

For cost analysis, Remedial Action Cost Engineering and Requirements (RACER) software was

used to estimate site-specific costs. Note that these costs are only estimates and do not represent

real-world value, since cost is modeled without consideration of the unique components of the

site. However, these estimates can be used for comparative purposes for cost analysis since the

calculations are based on the same assumptions. RACER supporting documentation can be found

in Appendix B, which includes detailed cost outlines and a list of assumptions for each cost

estimate.

The detailed evaluation is presented in Appendix C. A summary is presented below, along with a

comparison of the alternatives.

4.1 NAPL REMOVAL OPTIONS

4.1.1 Dual Phase Extraction

DPE is often selected because it enhances groundwater and/or product recovery rates, especially

in layered, fine-grained soils. The application of DPE also maximizes the effectiveness of SVE

by lowering the water table and therefore increasing air-phase permeabilities in the vadose zone.

4.1.1.1 Effectiveness

The EPA recommends an initial screening for effectiveness before a more detailed analysis is

conducted (EPA, 1995). For DPE, systems, the initial screening focuses on two parameters:

permeability of the petroleum-contaminated soils, and volatility of the petroleum constituents.

Permeability affects the rates at which groundwater and soil vapors can be extracted and controls

the pore volume exchange rate; this can be generalized by soil type. Volatility determines the



rate at and degree to which petroleum constituents will vaporize to the soil vapor state; volatility

can be estimated by boiling point. These two parameters will indicate whether the site is

amenable to DPE, as extraction efficiency is largely dependent on these generalized parameters.

The majority of the Roi-Namur POL Yard Spill Site is located on dredge fill, containing

unconsolidated fine- to coarse-grain coralline sand with some gravel and/or medium to large

coral fragments. This dredge fill is present to below the level of groundwater over most of the

site. The underlying natural geology (as determined by soil boring logs – see Appendix D),

which is present at decreasing depths over the more northern sections of the site, is also layered

coralline sand of similar composition. According to EPA guidance, silty or clean sand has an

intrinsic permeability of between approximately 10-10

and 10-5

square centimeters (cm2),

indicating that DPE will be effective or highly effective in these soils (EPA, 1995).

The main source of contamination at the Roi-Namur POL Yard Spill Site is diesel fuel, although

heavier oils and also solvents may also be present due to an oil/solvent pit that was historically

operated just south of the two storage ASTs (Figure 1-1). EPA guidance indicates that diesel fuel

is amenable for DPE systems, and will be of average effectiveness. For solvents, DPE will be

more effective, while for heavier oils, it will be less effective; however, since this would be the

first remediation step in a treatment train, the remaining constituents can be treated using other

means (described in Section 3.3.2).

Since initial screening has confirmed the DPE will potentially be effective, a more detailed

analysis of effectiveness was conducted and is presented in Appendix C. Effectiveness of the

DPE system depends on the following site characteristics and chemical properties (EPA, 1995):

Site Characteristics

Intrinsic permeability

Soil structure and stratification

Moisture content in the unsaturated zone

Depth to groundwater

Chemical Properties



Effective volatility

Chemical sorptive capacity

Table 4-1 summarizes the effectiveness of DPE for known conditions at the site along with a

summarized explanation.

Table 4-1 DPE Effectiveness Evaluation

Parameter Effective? Reason


Intrinsic

permeability

Yes Intrinsic permeability most likely lies between 10-8

to 10-5

cm2, in the highly effective range.

Soil structure and

stratification

Yes While definite stratification exists in sections below fill

material, most layers are primarily composed of sand, with

little finer materials noted.

Moisture content

in the unsaturated

zone

No High moisture content in the soil would mean higher

amounts of groundwater would be extracted and need to be

processed.

Depth to

groundwater

No Depth to groundwater is very shallow, usually located at

approximately 6 feet bgs. This indicates a high potential for

air-flow short circuiting to the surface. Additionally,

groundwater levels fluctuate at the site due to tidal forces.

This would cause further design complexities.

Chemical Properties

Effective volatility Yes Chemical-specific parameters indicate low volatility of

contaminants. However, the system could be designed to

extract NAPL on the groundwater surface, increasing

effectiveness.

Chemical sorptive

capacity

No Chemical-specific parameters indicate that the contaminants

would adhere to the soil rather than dissolve in soil moisture,

indicating low effectiveness. However, further site-specific

data is required to estimate effectiveness.

4.1.1.2 Implementability

The applicable advantages and disadvantages of DPE systems are presented below, derived from

generalized advantages and disadvantages presented by the EPA (EPA, 1995).

Advantages:

Proven performance under a wide range of conditions; readily available equipment.

Minimal disturbance to site operations.



Short treatment times (usually six months to two years under optimal conditions).

Flexible applications to sites with water table fluctuations or widely ranging

permeabilities.

Can be applied to sites with floating product, and can be combined with other

technologies, such as bioremediation.

Can be used under buildings and other locations that cannot be excavated.

Disadvantages:

May require costly oil/water separation and groundwater treatment.

Requires complex monitoring and control during operation.

4.1.1.3 Cost

The key cost drivers are (FRTR, 2007):

Soil Type

o Soil type determines permeability, which is the primary cost driver. DPE

extraction works best for permeable sand-silt mixtures. Impermeable (clayey) or

excessively permeable (gravel/sand) soils are more difficult to implement.

Depth to Base of Contamination

o Depth to the base of contamination is the secondary driver, as an increased

thickness and depth of contaminated groundwater increases cost.

A rough estimate for a cost of small and large sites for VOC contamination, being both easy (soil

composed of sand-silt/silty-sand mixture) and difficult (soil composed of silt/silty-clay mixture)

and using carbon adsorption for gas and liquid treatment, range from $23,460 to $54,545 per

1000 cubic yards (CYs) processed (this would not include additional shipping costs for required

materials to reach the atoll, nor difficulties encountered from inefficiencies described in the

above sections) (FTRT, 2007). This brings the total cost to somewhere between approximately

$525,000 and $1,220,000, assuming an affected area of 150,000 square feet and the affected

depth of 4 to 8 feet bgs.



RACER software was used to estimate site-specific costs for DPE at the Roi-Namur POL Yard

Spill Site. Assuming that vapor emissions were processed using carbon adsorption filters,

product and groundwater mix were processed using an oil/water separator, and NAPL was

drummed before being burned on-site, the cost of NAPL removal was approximately $1,400,000

(including mark-up and professional labor management). Direct costs for this estimate compare

to the range of costs noted above.

4.1.2 Bioslurping

Bioslurping is very similar to DPE, but uses a single-pump design to extract contamination

groundwater, floating product, and soil gas. The system is also amenable to conversion into a

traditional bioventing system after extraction is complete. It is a cost-effective in situ remedial

technology that simultaneously accomplishes LNAPL removal and soil remediation in the

vadose zone.


The discussion for effectiveness of DPE systems also applies to bioslurping systems, since the

concept behind the technologies is the same (see Section 4.1.1.1). Differences in the systems are

described in the Implementability sections.

Additionally, two case studies are noted in the FRTR technologies guidance, and are described

below.

The U.S. Navy has used bioslurping at Naval Aviation Facility in Fallon, Nevada. This system

was able to remove 6,500 gallons of JP-5 jet fuel during 1993, with operation 75% of the time

(FRTR, 2007).

The U.S. Air Force used a bioslurper on the island of Diego Garcia to pull out JP-5 at the site

where jet fuel leaked into the ground during the Persian Gulf War. The recovery rate of JP-5

averaged about 1,000 gallons per month (FRTR, 2007).




The applicable advantages and disadvantages of bioslurping systems are presented below,

derived from generalized advantages and disadvantages presented by the EPA (EPA, 1995).

Advantages

Proven performance in low-permeability soils. Requires no down-hole pumps.

Minimal disturbance to site operations.

Short treatment times (usually six months to two years under optimal conditions).

Can be applied at sites with floating product, and can be combined with other

technologies, such as bioremediation.

Can be used under buildings and other locations that cannot be excavated.

Disadvantages

Difficult to apply to sites where the water table fluctuates.

Treatment may be expensive for extracted vapors and for oil-water separation.

Can extract a large volume of groundwater that may require treatment.

Requires specialized equipment with sophisticated control capacity

Requires complex monitoring and control during operation.

4.1.2.3 Cost

Bioslurping of LNAPL at multiple Air Force sites had an average cost of $56 per gallon of

LNAPL recovered (FRTR, 2007). Assuming 10,000 gallons remain at the site (a conservative

estimate based on the amount of product known to have spilled and known to have been

recovered), this gives an estimated cost of $560,000; however, this cost estimate is likely low,

since conditions and the isolated location of Roi-Namur Island will drive up costs considerably,

and will likely be only slightly lower than the estimated costs for DPE presented in Section

4.1.1.3.

RACER software was used to estimate site-specific costs for bioslurping at the Roi-Namur POL

Yard Spill Site. Assuming that vapor emissions were processed using carbon adsorption filters,



product and groundwater mix were processed using an oil/water separator, and NAPL was

drummed before being burned on-site, the cost of NAPL removal was approximately $2,000,000

(including mark-up and professional labor management).

4.1.3 Infiltration Galleries

Infiltration galleries are trenches installed to a level below the surface of groundwater, with

porous wall stabilizers that allow product and groundwater to pool in the trenches. Sump pumps

or skimmers are used to extract product and groundwater, which continues to refill into the

trenches due to passive diffusion from the hydraulic gradient and groundwater flow.


Effectiveness of infiltration gallery extraction depends primarily on the ability of product to flow

into the collection trenches, and then the success of product collection from these trenches (EPA,

1996).

The fate-and-transport of liquid petroleum products in the subsurface is determined primarily by

the properties of the liquid and the characteristics of the geologic media into which the product

has been released. Properties that determine the effectiveness include (EPA, 1996):

Chemical Properties

Density

Viscosity

Interfacial tension

Soil Properties

Porosity

Permeability

Combined Properties

Chemical sorptive capacity



Capillary pressure

Relative permeability

Wettability

Saturation

Residual Saturation

Table 4-2 summarizes the effectiveness of infiltration galleries for known conditions at the site

along with a summarized explanation.


The advantages and disadvantages of infiltration gallery NAPL removal are described below.

Advantages

Works with and enhances natural in situ processes already at play (typically uses natural

groundwater gradient, naturally occurring biodegradation)

Can be a low-energy approach

Can have simple operation and monitoring requirements

Can be used in tandem with other remedial technologies that address small amounts of

residual soil and groundwater contamination

Short treatment times (usually six months to two years under optimal conditions)

Can be applied at sites with floating product, and can be combined with other

technologies, such as bioremediation

Can be used to control migration of contaminants (e.g., flow into the lagoon)

Disadvantages

Can extract groundwater that may require oil-water separation and treatment

Requires specialized equipment with sophisticated control capacity

Will not be able to reduce contaminants to background or very low concentrations

Must be accompanied by other technologies to address residual contamination

May require significant trenching to be effective



Table 4-2 Infiltration Galleries Effectiveness Evaluation


Chemical Properties

Density Yes NAPL density is less than that of water, so it will

be amenable to collection in trenches.

Viscosity Yes Since diesel fuel (even when emulsified) and

water have relatively low viscosities, they can be

expected to flow through a porous medium fairly

easily.

Interfacial

tension

N/A Effectiveness due to interfacial tension is included

in the discussion of other parameters.

Soil Properties

Porosity N/A The calculated porosity is quite porous (the

material is primarily unconsolidated fill material),

indicating that large volumes of liquid can be held

in the soil.

Permeability Yes Estimated permeability values indicate that soils

are fairly permeable, meaning the soils are

amenable to fluid flow.

Combined Properties

Chemical

sorptive

capacity

No Chemical-specific parameters indicate that the

contaminants would adhere to the soil rather than

dissolve in soil moisture, indicating low

effectiveness. However, further site-specific data

is required to estimate effectiveness.

Capillary

pressure

N/A Additional measurements are required to estimate

effectiveness for infiltration galleries based on

this parameter.

Relative

permeability

No Since NAPL at the site is emulsified, there is

likely a mix of water and diesel fuel near the

water table, which means that the relative

permeability would be reduced. However,

rainwater flow through would help flush

contaminants in the pore space.

Wettability N/A A factor in other parameters

Saturation N/A A factor in other parameters

Residual

saturation

No Residual saturation levels tend to be much higher

in the saturated zone than in the unsaturated zone.

There are multiple types of NAPL removal systems that can be used to extract NAPL from

collection trenches with little collection of groundwater. Either a floating collection apparatus or

a belt skimmer would be the best options for NAPL removal. Rationale for this conclusion is

presented in Appendix C.



4.1.3.3 Cost

Since infiltration galleries were not included in the FRTR screening matrix, RACER software

alone was used to estimate site-specific costs for this NAPL removal strategy. Assuming that 900

feet of trenching was installed, NAPL was removed with belt skimmers powered by solar panels,

clean overburden was stockpiled, contaminated soil was landfarmed, and the NAPL could be

stored in drums before being burned on-site, the total cost was estimated to be approximately

$850,000 (including mark-up and professional labor management).

4.2 REMEDIAL OPTIONS

4.2.1 Enhanced Bioremediation

Enhanced bioremediation technologies are used to accelerate naturally occurring in situ

bioremediation of contaminants by indigenous microorganisms in the subsurface. The basic

principle is to supply these microorganisms with the necessary nutrients to optimize contaminant

degradation rates.


The EPA recommends an initial screening for effectiveness before a more detailed analysis is

conducted (EPA, 2004). For enhanced bioremediation systems, the initial screening focuses on

the following overall assessments for viability:

Free mobile product is present and the corrective action plan does not include plans for

its recovery.

Potentially excessive risks to human health or the environment have been identified and

the corrective action plan does not include a supplemental mitigation plan.

The target contaminant zone includes unstratified dense clay.

None of these conditions are true for the Roi-Namur POL Yard Spill Site. While free mobile

product is present, enhanced bioremediation is being considered as the step following product

removal in a treatment train. Likewise, since risk to human health has been identified at the site



from RSL exceedances, a more rapid remedial approach is being considered for the NAPL

removal, which will mitigate these risks.

Since initial screening has confirmed enhanced bioremediation will potentially be effective, a

more detailed analysis of effectiveness was conducted. The analysis primarily focused on

enhanced aerobic bioremediation, although enhanced anaerobic bioremediation was also

mentioned. Many factors influence the effectiveness of enhanced bioremediation at a site, and

include (EPA, 2004):


Oxygen demand factors

Oxygen demand from biodegradation of organic compounds

Microbial population

Nutrients

pH

Temperature

Inorganic oxygen demand

Advective and Dispersive Transport Factors

Intrinsic permeability

Soil structure and stratification

Hydraulic gradient

Depth to groundwater

Iron and other reduced inorganic compounds dissolved in groundwater

Constituent Characteristics

Chemical class and susceptibility to bioremediation

Contaminant phase distribution

Concentration and toxicity

Bioavailability characteristics (solubility and Koc factor).



It should also be noted that the two most important factors to consider for enhanced

bioremediation effectiveness are saturated soil permeability and chemical-specific

biodegradability, so these parameters were given higher consideration when determining overall

effectiveness of this technology. Table 4-3 summarizes the effectiveness of enhanced

bioremediation for known conditions at the site along with a summarized explanation.


The applicable advantages and disadvantages of enhanced bioremediation systems are described

below, as derived from generalized advantages and disadvantages (EPA, 2004).

Advantages

Works with and enhances natural in situ processes already at play (typically uses natural

groundwater gradient, naturally occurring biodegradation)

Destroys the petroleum contamination in place.

Produces no significant wastes (off-gases or fluid discharges)

Can be a low-energy approach

Is relatively inexpensive

Complements more aggressive technologies (e.g., groundwater extraction) and less

aggressive approaches (e.g., intrinsic remediation) that can be integrated into site

remediation.

Causes minimal disturbance to site operations

Has simple operation and monitoring requirements

Is potentially more reliable than other, more active remedial technologies (e.g.,

groundwater extraction and treatment)

Can be used in tandem with other remedial technologies that address small amounts of

residual soil and groundwater contamination



Table 4-3 Enhanced Bioremediation Effectiveness Evaluation



Oxygen demand

factors Yes

Dissolved oxygen readings indicate that groundwater is fairly easily

oxygenated

Oxygen demand

from

biodegradation of

organic compounds

N/A

Depending on the effectiveness of the NAPL removal technology

utilized, the residual levels of petroleum hydrocarbon contamination

remaining on site could vary substantially.

Microbial

population Yes

Studies have shown that microorganisms exist that are adapted and

able to degrade hydrocarbon contaminants (ORNL, 1991a)

Nutrients No Supplements would likely be required to ensure enhanced

bioremediation would be effective.

pH Yes Groundwater is closely centered on pH 7, meaning that it is amenable

to enhanced bioremediation.

Temperature Yes Temperatures are in the range for highly effective enhanced

bioremediation.

Inorganic oxygen

demand Yes

Analytical results indicate that inorganic oxygen demand would be

low.

Advective and Dispersive Transport Factors

Intrinsic

permeability Yes

Enhanced bioremediation is effective if the intrinsic permeability is

greater than approximately 10-9 cm2 (EPA, 2004), which estimates

indicate is the case.

Soil structure and

stratification Yes

Soil boring logs and grain size analysis indicates that the existing

geology is amenable to enhanced bioremediation.

Hydraulic gradient No Hydraulic gradient is assumed to be relatively flat.

Depth to

groundwater Yes

The shallow depth to groundwater will likely make oxygenation more

effective than for deeper water.

Iron and other

reduced inorganic

compounds

dissolved in

groundwater

No Analysis of groundwater indicates that these components are not

present in significant quantities.

Constituent Characteristics

Chemical class and

susceptibility to

bioremediation

Yes

According to the EPA, DRO (the primary COC) and GRO are

amenable to biodegradation, and are approximately in the middle of

the range for effective degradation (EPA, 2004).

Contaminant phase

distribution N/A

The success of the removal action will determine the success of

enhanced bioremediation.

Concentration and

toxicity N/A

The success of the removal action will determine the success of

enhanced bioremediation.

Bioavailability

characteristics

(solubility and Koc

factor)

No

Chemical-specific parameters indicate that the contaminants would

adhere to the soil rather than dissolve in soil moisture, indicating low

effectiveness. However, further site-specific data is required to

estimate effectiveness.



Disadvantages

May have longer remedial time frames than more aggressive approaches

May not be able to reduce contaminants to background or very low concentrations

Typically requires long-term monitoring of residual contamination in soil and

groundwater

May not be fully effective on all petroleum hydrocarbons and product additives

Can be misapplied to remediation at some sites if the conditions for use are not fully

understood

Contamination at the Roi-Namur POL Yard Spill Site is primarily in the saturated zone, with

NAPL floating on the groundwater. Evaluation of all oxygenation techniques indicated that

oxygen releasing compounds or biosparging would be the best options to implement. Rationale

for this conclusion is presented in Appendix C.

Additional site-specific factors that may limit the implementability enhanced bioremediation at

the Roi-Namur POL Yard Spill Site include:

Inadequate removal of NAPL could retard microbial proliferation.

High contaminant concentrations have been found in groundwater close to the lagoon that

has high levels of dissolved ions; previous studies have not been performed to indicate

how salinity affects microbial degradation of hydrocarbon contamination.

4.2.1.3 Cost

Bioremediation treatment does not require heating, requires relatively inexpensive inputs, such

as nutrients, and usually does not generate residuals requiring additional treatment or disposal.

Also, when conducted in situ, it does not require excavation of contaminated media. Compared

with other technologies, such as thermally enhanced recovery (discussed in Section 4.2.2),

bioremediation may provide a cost advantage (FRTR, 2007).

Typical costs for enhanced bioremediation range from $20 to $80 per CY of soil (not including

material, equipment, and personnel transportation costs or personnel wages); total costs from

these estimates would be from approximately $650,000 to $2,500,000, assuming an affected



volume of approximately 32,074 CY (4 to 8 feet bgs over 216,500 square feet). Factors that

affect cost include the soil type and chemistry, type and quantity of amendments used, and type

and extent of contamination. Effectiveness of developed systems increases with time.

Infrastructure used for bioventing/biosparging activities associated with bioslurping could be

used as an injection well for air or other nutrients to reduce installation costs (FRTR, 2007).

RACER software was used to calculate a site-specific estimate of the costs for enhanced

bioremediation at the Roi-Namur POL Yard Spill Site, using biosparging and injection wells.

Total costs, including mark-up and professional labor management, were approximately

$2,800,000; excluding mark-ups, this is within the cost estimates noted above.

4.2.2 Thermal Treatment

Thermal treatment uses electrical resistance/electromagnetic/fiber, optic/radio frequency heating,

or hot-air/steam/hot water injection to increase the volatilization rate of semi-volatiles and

facilitate extraction. The process is otherwise similar to standard SVE, but requires heat resistant

extraction wells.


Factors that may limit the applicability and effectiveness of the process include (FRTR, 2007):

Soil type, contaminant characteristics and concentrations, geology, and hydrogeology. While the

characteristics of the site geology that contribute to effectiveness are the same for standard SVE,

heat-based in situ remediation techniques can overcome or lessen the limiting contaminant

characteristics (EPA, 1997).

Table 4-4 summarizes the effectiveness of thermal treatment for known conditions at the site

along with a summarized explanation.



Table 4-4 Thermal Treatment Effectiveness Evaluation


Intrinsic permeability Yes

Estimated permeability values indicate that

soils are fairly permeable, and would be

effective for thermal treatment

Soil structure and stratification Yes

Soil boring logs indicate that the existing

geology is amenable to thermal treatment, as

preferential flow would not be expected to

occur.

Depth to groundwater No

Special considerations must be taken at sites

where groundwater is located at less than 10

feet bgs due to groundwater upwelling and

extraction short-circuiting (EPA, 1994).

Moisture content No

The body of contamination is in soils with a

significant amount of moisture, which would

decrease effectiveness.

Chemical properties Yes Addition of heat would make extraction of

DRO and PAHs much more effective.


The three general methods used to apply heat during thermal treatment are: injection of hot gases

such as steam or air, electromagnetic energy heating, and hot water injection. Based on a flow

chart provided by the EPA for site-specific parameters at the Roi-Namur POL Yard Spill Site,

either steam or hot water injection are the preferred methods (EPA, 1997). After a thorough

evaluation of both injection methods (presented in Appendix C), steam injection was identified

as the preferred technology. The applicable advantages and disadvantages of steam injection are

described below.

Advantages

Does not require chemicals of any sort to be injected in the subsurface

Minimal disturbance to site operations

Excavation is not required

Short treatment times

Easily combined with other technologies

Can be used under buildings and other locations that cannot be excavated

Studies and pilot studies have proven the technology to be effective in sandy soils



Disadvantages

Residual concentrations of contaminants will likely remain

Generally more costly than ex situ procedures, especially for shallow contamination

Shallow groundwater requires special design considerations

May require costly treatment for atmospheric discharge of extracted vapors

Requires a significant amount of energy to heat up the steam

Requires treatment of extracted mixture

Complex sampling and monitoring required

Complex modeling required to design appropriate systems

4.2.2.3 Cost

The most significant factor affecting cost is the time of treatment or treatment rate. With a

mobile system, treatment rate is influenced primarily by the soil type, waste type, and on-line

efficiency. Cost estimates for this technology are strongly dependent on the treatment rate and

range. On average, the cost ranges from $100 to $300 per CY based on a 70 percent on-line

efficiency (FRTR, 2007). This means that the total cost based on an affected area of 216,500

square feet with a treatment depth of 4 feet (4 to 8 feet bgs) would be between approximately

$3,200,000 and $9,600,000.

In depth analysis using RACER software was not conducted for thermal treatment, as the

physical parameters for the site (primarily depth to contamination) do not meet the calculation

requirements of the software.

4.3 COMPARATIVE ANALYSIS OF ALTERNATIVES

Since a treatment train is necessary for complete remediation, treatment options will be discussed

in terms of NAPL removal and residual contamination remediation. Significant factors

influencing effectiveness and implementability will be discussed for each technology, and a cost

comparison for each technology can be found for each phase of the treatment train.



4.3.1 NAPL Removal

4.3.1.1 Dual Phase Extraction

Soil properties at the site are amenable to DPE. However, high moisture content could inhibit

airflow into the subsurface, which would mean that more groundwater would be extracted with

the NAPL. Additionally, since the body of contamination is close to the surface, extraction short-

circuiting to the surface could occur, which would substantially decrease efficiency; a cap would

likely be necessary to ensure this would not happen. Contaminant properties would likely not

affect efficiency or implementability. However, the main disadvantage of DPE is that since the

product is emulsified (meaning it is suspended in groundwater), large volumes of product and

groundwater mixed together would be extracted that would require separation before the NAPL

could be disposed of. This would likely increase costs substantially.

4.3.1.2 Bioslurping

Bioslurping is almost identical to DPE, except that it is less applicable to sites with fluctuating

groundwater depths, as is the case at the Roi-Namur POL Yard Spill Site due to tidal effects.

Therefore, while bioslurping has the potential to be less expensive than DPE, it is less applicable

to the site. Otherwise, the discussion for DPE presented above also applies to bioslurping.

4.3.1.3 Infiltration Galleries

While soil properties are amenable to product flow, the relative permeability is likely low due to

emulsification of the product at the site. The soil is generally porous and has fairly high

permeabilities, but the relative permeability of the product is reduced substantially due to the

presence of water in the pores. Additionally, since the hydraulic gradient is essentially flat, flow

rates into extraction trenches would be very low, although this may be increased by the frequent

rain showers. Due to these factors, the area of effect for each trench might be limited, which

would require installation of more trenches; also, for NAPL under buildings at the site, it might

be difficult for product to migrate out from under them (especially the ASTs and associated

secondary containment). Product would also have to be separated out in the trenches before

extraction (using hydrophobic membranes or other means), otherwise oil/water separation would

be necessary.



4.3.1.4 Cost Comparison

Since DPE and bioslurping are essentially identical, except that bioslurping is less applicable to

conditions at the Roi-Namur POL Yard Spill Site, only DPE and infiltration galleries will have

their costs compared below.

RACER software cost estimates for DPE were $1,400,000, while cost estimates for infiltration

galleries were $850,000. Additionally, costs for DPE would increase dramatically if a cap was

required to prevent short-circuiting. This uncertainty, along with the fact that extraction trenches

were used successfully at this site during initial response activities, indicates that infiltration

galleries would be the most cost-effective option for residual remediation.

4.3.2 Remedial Technologies


The geologic features at site are amenable to enhanced bioremediation. Low groundwater flow

rates would retard oxygen and nutrient dispersion, but this could be accounted for using good

engineering practices. However, the advantages are balanced out by the nature of the COCs that

remain, as they are largely insoluble and have high Koc constants, indicating that their

bioavailability would be limited. Additionally, separate phase product remains at the site, which

would have to be removed prior to the implementation of enhanced bioremediation. This means

that the success of the NAPL removal would indicate how effective enhanced bioremediation at

the site could be.

4.3.2.2 Thermal Treatment

While the geologic features at the site are amenable to thermal treatment (moisture content is

likely a little higher than ideal values), and the contaminants would also likely be amenable to

extraction once properly heated, the shallow depth to the body of contamination invalidates this

technology as a viable option for residual remediation. This is primarily due to the fact that the

overburden pressure is provided by only a few feet of soil, which would cause a high risk of

surface fracturing. Vapor recovery could potentially be an issue as well, since constituents would

be heated up significantly before extraction.



4.3.2.3 Cost Comparison

RACER software cost estimates for enhanced bioremediation were $2,800,000, while FRTR cost

estimates for thermal treatment ranged from $3,200,000 to $9,600,000. This, along with the fact

that thermal treatment is likely an unviable option due to risks of surface fracturing, indicates

that enhanced bioremediation would be the most cost-effective option for residual remediation.

4.4 REMEDY OF RECORD

Comparisons of effectiveness, implementability, and costs indicate that a treatment train of

infiltration galleries followed by enhanced bioremediation would be the most cost effective

strategy for NAPL removal and residual remediation at the Roi-Namur POL Yard Spill Site.

Infiltration galleries were identified as the preferred NAPL removal strategy at the site primarily

due to uncertainty in the other technologies analyzed. While this technology would likely take

longer than DPE or bioslurping due to slow product migration in the subsurface, high vacuum

extraction associated with the latter technologies might not be applicable at the site due to short

circuiting from the proximity of the contamination to the surface (which would increase costs

substantially). Extraction trenches were used as part of the initial spill response at the site, so it is

known that they are at least somewhat effective for NAPL removal. Note that although

infiltration galleries would require more extensive soil excavation than for DPE or bioslurping,

the Cultural Resource Evaluation (CRE) (included as Appendix E) has indicated that this is not a

detriment since the area is located in post-WWII dredge fill and would not require monitoring.

Enhanced bioremediation was identified as the preferred overall strategy for residual remediation

at this site for multiple reasons. First, it allows the primary contaminant (DRO) to be degraded

without excavation or ex situ treatment necessary. It is also very cost effective, since it

supplements natural processes with the need for little additional infrastructure. Finally, multiple

feasibility studies and data collected during the SI (Sivuniq, 2011) have determined that

conditions on the Kwajalein Atoll are amenable for enhanced bioremediation. Results from

bioremediation parameters, as well as water quality parameters (i.e. oxygen reduction potential),

indicate that natural attenuation has occurred at the Roi-Namur POL Yard Spill Site, but is

nutrient limited.



Design concepts for this treatment train are provided in Section 6.0. Section 7.0 provides the

management plan for implementation, including the work plan elements required by the UES.

4.5 CULTURAL RESOURCE EVALUATION

Based on the above remedy of record, a CRE was conducted on possible effects on cultural

resources during implementation of the treatment train. The CRE concluded that future

investigational and remedial activities at Roi-Namur POL Yard Spill site have little or no

probability of effects to cultural resources. This is primarily because the portion of Roi-Namur

Island where these activities will take place was created by lagoon dredging in the immediate

aftermath of World War II. The CRE is presented in its entirety in Appendix E.



5.0 FUTURE PRE-REMOVAL ACTION ACTIVITIES

Additional design-related investigation activities beyond those completed to date are being

conducted to support the removal and remedial action design of a treatment train of infiltration

galleries followed by enhanced bioremediation. A summary of planned tasks is provided below.

These activities are a continuation of the activities initiated as part of the 2010 and 2011 SI, and

are fully outlined in the supplemental work plan (Sivuniq, 2011). Results of these activities will

be integrated into the Data Evaluation report deliverable, as well as the removal and remedial

action work plan.

Perform a site topographic survey

Install vertical control monuments to ensure site survey control

Collect soil lithology/classification data

Verify nature of soil contamination

o Sample for PCBs near the old power plant

o Sample for solvents/PCBs near the former oil spill

o Collect surface samples to support residential receptor risk assessment

Verify extent of soil contamination

o Define extent near vicinity of former wash rack (NE of containment basin)

o Define extent near septic leach field

o Define extent of soil contamination near SB63

Verify nature of groundwater contamination

o Sample for chlorinated solvents/PCBs near former wash rack

o Sample for chlorinated solvents/PCBs near former oil pit

Verify extent of groundwater contamination

o Define extent north/west of containment basin

Install network of permanent monitoring well points

Collect accurate depths to product and groundwater

LNAPL

o Accurately measure thickness of LNAPL at groundwater interface

o Characterize composition of emulsified LNAPL layer

Remediation data



o Accurately measure microbial population as colony forming units

o Accurately measure nutrients levels up- and downgradient within holding times

Hydrogeology

o Accurately measure groundwater flow rate through formation (conductivity)

o Accurately measure head effects on lateral groundwater flow (storativity)

o Accurately define tidal influence area and magnitude with depth

Results from previous investigations, as well as results from planned activities, will be evaluated

and interpreted during the remedial design. Interpretation of this data will be included in the

design concepts described in Section 6.0. Evaluation of data collected to date and identification

of data gaps are ongoing, so design-related investigation activities beyond those listed above may

be appropriate.



6.0 REMOVAL ACTION SYSTEM DESIGN PROCESS

This section describes the system elements, system design concepts, and schedule for the

removal action system design. The design and construction of removal action system

components will be performed concurrently, where appropriate, to expedite the removal action

schedule and allow the treatment train system design to be flexible as contaminant

concentrations change. Design drawings and plans will be included as part of the removal and

remedial action work plan, upon completion of the supplemental data collection described in

Section 5.0.

6.1 REMOVAL AND REMEDIAL ACTION SYSTEM ELEMENTS

The primary elements of the selected technologies to be used in the treatment train described in

Section 4.4 include:

Infiltration galleries

o Trenches

Stockpile clean overburden

Landfarm contaminated soil

o Trench boxes

o Belt skimmers

o Overhead power connections

o Product storage

Landfarming cell

o Tilling machine

o Cover

o Nutrient application

Enhanced bioremediation

o Injection points/air sparging points

o Injection/air pumps

o Overhead power connections

Habitat restoration

o Landfarmed soil and clean overburden as backfill



Institutional controls during implementation

o Rope off treatment area

Long-term operation, maintenance, and monitoring

o Hazardous waste management

o Periodic sampling

o Periodic maintenance

o System optimization

6.2 DESIGN AND PERFORMANCE CRITERIA

6.2.1 Cleanup Goals

The USAKA UES (USAKA, 2011) provide a regulatory framework for restoration activities at

this site. The UES were developed from United States Government statutes, Republic of

Marshall Islands statutes and International agreements (USAKA, 2011).

A review and comparison of chemical data against published screening criteria (EPA RSLs, and

GEPA ESLs) was used to identify chemicals of potential concern; additionally, contaminants

detected in piezometers installed in the tidal zone were screened against NOAA SQuiRTs lowest

observed effect levels (LOELs), where available, to screen for ecological risk.

For matrices where at least one screening criterion exceedance was noted, all contaminants that

had maximum or upper confidence limit (UCL) 95 concentrations within 10% of applicable

screening criteria were retained as COCs (for the purposes of the data evaluation). COCs

identified at the site include benzo(a)anthracene in soil; benzo(a)pyrene in soil; GRO in soil;

naphthalene in soil; phenanthrene in soil; and DRO in soil and groundwater. All of these

contaminants will be monitored throughout the life of the removal action, and will form the basis

of performance criteria that removal efficiency is based on. Current and target COC

concentrations are presented in Table 6-1; this table will be updated after collection of the

supplemental data described in Section 5.0. Target concentrations were derived from ARARs,

which included evaluation of residential and industrial EPA RSLs and GEPA ESLs, and EPA

risk-based SSLs if there was no other applicable criteria; these screening levels were used as

planning-level target concentrations. EPA maximum contaminant level (MCL)-based SSLs were



not used because the groundwater in the vicinity of the site is nonpotable. Target concentrations

will be refined based on pathway-specific evaluation once supplemental data is collected, and

will be reported in the Data Evaluation report deliverable pursuant to 3-6.5.8(l)(3).

Table 6-1 Current and Target COC Concentrations

Soil

Analyte Frequency UCL 95 or Maximum

(mg/kg)

Screening Criteria / Initial Target

Concentration (mg/kg)

Benzo (a) anthracene 5 / 64 0.0158 0.151

Benzo (a) pyrene 1 / 64 0.00325 0.0151

DRO 46 / 66 5,750 5002

GRO 17 / 66 14.78 1002

Naphthalene 19 / 64 1.124 3.61

Phenanthrene 27 / 64 1.462 10.692

Groundwater

Analyte Frequency UCL 95 (µg/L) Screening Criteria / Initial Target

Concentration (µg/L)

DRO 3 / 11 1,310 6402

Notes, Acronyms and Abbreviations: 1 Screening levels based on EPA residential RSLs.

2 Screening levels based on GEPA ESLs (unrestricted land-use scenario with a nonpotable water source and shallow contamination).

UCL = upper confidence limit.

6.2.2 Performance Criteria

Requirements for measuring the effectiveness of the removal action are described in UES 3-

6.5.8(i). The overall goal of the removal action is to render a NFA determination for the site,

pursuant to UES 3-6.5.8(i)(2). All supporting data and rationale to support this determination

shall be documented in a formal report which will be made available for 30 days for public

review and comment. This report will detail evidence that removal has been completed and/or

that the associated exposure risks have been reduced to acceptable levels. An NFA designation is

an endpoint, meaning that all requisite mitigation work and evaluation has been fully

implemented.

Effectiveness will be monitored throughout the project to ensure that the endpoint will be a NFA

designation; modifications to implementation will be necessary if measured effectiveness will

not achieve this endpoint. Applicable performance criteria for each phase of the removal action

are described below, along with potential modifications to the system to improve efficiency.



6.2.2.1 NAPL Removal

The key performance criterion for the NAPL removal phase of the removal action is the NAPL

removal rate. This criterion is determined by many factors, but will primarily be based on the

ability of the NAPL to migrate through the subsurface and the holding capacity of the soil. After

supplemental data is collected, the system design will be modified to accommodate for site

conditions. Monitoring of the amount of NAPL removed, as well as the water content, will also

determine success of the removal system.

Water content in NAPL removed will primarily be a function of the belt material. Since the

contamination is primarily DRO, the belt material will be selected to be most effective at

selectively absorbing DRO. Water content in the removed material will be monitored, and

adjustments to the belt material will be implemented if the water content is too high.

The area of effect for each infiltration gallery will also determine the success of the removal

action. This will be determined by measuring product thickness in monitoring wells throughout

the site. If the NAPL is not mobile enough to be captured by the planned trenching, the location

and length of the trenches may be modified to capture as much product as possible. Additionally,

trenches will be placed in a manner to intercept any contaminant migration towards the lagoon.

Sampling on the shoreline will indicate success of trench placement in this regard.

The latent contaminant concentration after NAPL removal levels off will primarily be

determined by the holding capacity of the soil. If concentrations are still relatively high, the

injection wells planned for the residual contamination removal phase could be installed while

trenching and extraction is still in place to try and use air sparging to push contamination through

the soil (while at the same time preparing the soil for enhanced bioremediation). The higher the

residual concentration, the longer enhanced bioremediation will take.


The first performance criterion that will be measured during the residual contamination reduction

phase will be the overall oxygenation of groundwater. This will determine when nutrients are

supplied, as well as the onset of contaminant concentration reduction. This will be accomplished



through air sparging. Modifications to air injection rates will be implemented to ensure that a

concentration of 2 mg/L of DO is achieved.

The rate of contaminant concentration reduction is a function of the amount of hydrocarbon-

degrading bacteria, the amount of available oxygen in the soil and groundwater, and the amount

of nutrients available. These components will be monitored through the duration of the removal

action, and augmented on a schedule determined by on-site conditions encountered.

The area of effect for each injection point/sparging well will determine how effectively nutrients

and oxygen are spread throughout the soil column. Collection of data to help model movement

through the soil column will be conducted during the supplement deployment. Additionally, on-

site conditions will be evaluated to determine if this modeled spacing needs to be adjusted.

The overall effectiveness of this phase is determined by the residual concentration after reduction

levels off. Presumably, contaminant reduction will level off after cleanup goals are met;

however, if this is not the case, other remedial options will be investigated and implemented to

ensure that contaminant concentrations are reduced to cleanup goals within the acceptable

timeframe.

6.3 SYSTEM DESIGN CONCEPTS

The treatment train for this removal action will consist of infiltration galleries for NAPL

removal, and enhanced bioremediation for residual contaminant reduction. The general design

for each of these systems is described below; design drawings and plans will be included as part

of the removal and remedial action work plan, upon completion of the supplemental data

collection described in Section 5.0.

6.3.1 Infiltration Galleries

The infiltration galleries will consist of 50 or 100 foot-long trenches, with trench boxes installed

in each for structural integrity as the length is progressed. Underneath the trench box, infiltration

tile for the collection of water and NAPL will be installed; porous material (i.e., gravel) will be

packed around the tile to facilitate flow. The trench will then be backfilled to surface grade with

clean native material after the trench box is removed as the length is progressed, leaving the end



of infiltration tile open to connect with the next section (where another trench box will have

already been inserted – segmental installation along the length). This is depicted in Figure 6-1

and Figure 6-2.

Trenches will be installed in areas of equal product thickness so contaminants are not transported

to less contaminated portions of the site. The dimensions of the trenches will be 4 feet wide by 8

feet deep, to ensure that there is adequate area for product collection and that the bottom of the

trench is well below the water table. The proposed locations of these trenches are presented in

Figure 6-3. A total of 4 100-foot and 8 50-foot trenches are tentatively scheduled for installation.

Note that placement near the secondary containment was done to draw out NAPL that is

presumed to reside underneath the tanks. Also note that placement downgradient (i.e., between

the tanks and the lagoon) was done to prevent further migration of contaminants into the lagoon.

Belt skimmers tied into the Roi-Namur Island electrical infrastructure will be used to extract

NAPL from the trenches, while leaving most water in the trenches (a hydrophobic material will

be used as the belt). Extracted NAPL will be stored in 55-gallon drums at each trench to reduce

the amount of piping and heavy equipment that will be necessary for each step of the project. A

planning-level schematic is shown in Figure 6-1 and Figure 6-2.

Soil excavated to install these trenches will be divided into clean overburden and contaminated

soil. The clean overburden will be stockpiled near the site to be used as backfill, while the

contaminated soil will be moved to an area designated for landfarming (that will use containment

to ensure the contamination does not migrate into subsurface soils). The soil will be spread out in

a 1-foot thick layer, and tilled on a regular schedule; nutrients will also be added to enhance

biodegradation. These nutrients will be the same nutrients as those described below for enhanced

bioremediation, and the landfarming will be used as a feasibility study to determine what

nutrients will be required for the residual contamination reduction phase of the treatment train.

Soils will be landfarmed until they can be used as fill, preferably to backfill infiltration galleries

if the timing is appropriate.

NAPL removal rates will be monitored, and soil and groundwater samples will be collected on a

regular schedule to ensure that the removal action is effective (see Section 6.2.2). Adjustments to

infiltration gallery installation and locations will be performed as necessary. Once contaminant



concentrations level off, the residual contaminant phase of the treatment train will be

implemented, and the trenches will be backfilled. Modification of the enhance bioremediation

phase approach will be conducted if contaminant concentrations cannot be lowered to a point

where enhanced bioremediation will be effective over the acceptable timeframe.



Figure 6-1 Infiltration Gallery Side View and Installation Procedure



Figure 6-2 Infiltration Gallery Planning-Level Schematic



Figure 6-3 Proposed Initial Locations for Infiltration Gallery Installation



6.3.2 Enhanced Bioremediation

Once NAPL removal has been initiated, injection wells will be installed in areas where

contaminant concentrations are elevated but NAPL does not exist (the fringe of the contaminant

plume). These injections wells will have a dual purpose: to be used as nutrient injection points by

mixed recirculated water from the NAPL removal process, and also to be used as air sparging

wells. Injection wells will be installed at approximately every 25 feet in the affected area;

however, this spacing will be adjusted based on the area of effect for each well (as determined

from data collected during supplemental data collection events). Positions will be moved towards

the center of the contaminant mass as NAPL is removed. Air sparging will be conducted until

groundwater oxygen reduction potentials indicate that the subsurface has 2 mg/L of DO or

higher. At this point, a step injection of nutrients will be conducted, after which air sparging will

continue at a level to keep groundwater DO concentrations at 2 mg/L or greater. Pumps used will

be tied into the Roi-Namur Island electrical infrastructure.

Soil and groundwater contaminant concentrations will be monitored, and adjustments to nutrient

injection and sparging rates will be implemented to increase reduction rates. Enhanced

bioremediation will continue until contaminant concentrations meet the cleanup goals described

in Section 6.2.1.

6.4 SCHEDULE

After obtaining all required approvals and authorizations, Sivuniq intends to execute this

proposed removal action system design in a timely fashion. Pending approvals, the fieldwork

will commence during July 2012, with the installation of removal action system structure

concluding within three months. The removal action system will be run until contaminant

concentration reduction becomes asymptotic (approximately one year, dependent on site

conditions), with landfarming of excavated soils conducted concurrently. Data will be collected

for a verification assessment upon completion of this phase.

Concurrently, the remedial action system will be installed, which will take approximately three

months. The system will then be run for approximately five years. Long-term monitoring will be

conducted over this time. Data collection, validation, and review will lead to status reports on a



regular schedule thereafter, with a final summary document upon conclusion of long-term

monitoring. The project schedule is presented in Appendix A.



7.0 PROPOSED WORK SUMMARY

This section summarizes the field activities planned for the restoration activities at the Roi-

Namur POL Yard Spill site, and will outline installation of components described in Section 6.1,

as well as associated sampling and monitoring activities. The work plan elements identified in

later sections and appendices to this document include screening, sampling, and analysis

strategies, safety considerations, operating procedures, and data validation approaches. Specific

and detailed procedures for these activities were included in the work plan for the SI and will be

adapted for future work at this site; the removal and remedial action work plan will provide site-

specific details beyond the generalized discussion presented in the following sections.

The SAP, presented in Section 7.3, provides generalized procedures related to the collection and

analysis of soil and water samples as well as other field activities that will be used by the Sivuniq

field team. The QAPP, presented in Section 7.4, describes the policies, organization, functional

activities, and the data quality objectives (DQOs) and measures necessary to obtain adequate

data.

The SSHP presented in Section 7.5 examines the hazards associated with performing

investigative work and describes the practices to be implemented to ensure worker safety.

An Archaeological Monitoring Plan (AMP) is provided in Section 7.6, and addresses the

significant concerns related to protecting and preserving cultural and historical resources at the

site. The generalized approach will be refined and republished in the removal and remedial

action work plan.

7.1 GENERAL FIELD ACTIVITIES

During field activities, Sivuniq and stakeholders provide active support to the field crews. The

support ensures satisfaction of logistical, advisory, and performance needs. The Sivuniq Project

Manager monitors and fills requests for personnel, material, and equipment during daily

communications with the Field Team Leader. Communication enhancements provided by

satellite telephone, Web-based platforms (i.e., SharePoint or FTP sites), and daily

teleconferences ensure that the management team and field crew share information and

coordinate activities.



Open communication within the office environment also provides affirmative guidance to Task

Managers and staff. Appointed Task Managers lead efforts related to data compilation,

evaluation, and validation, risk assessment, and reporting.

An office-based Data Manager organizes and analyzes information from the field to guide field-

screening efforts and achieve sampling objectives. Using Geographic Information System (GIS)

based analysis tools such as Visual Sampling Plan, dynamic data analysis identifies areas of

highest likelihood for contamination. Under the accelerated site characterization process, site

sampling focuses on the identification of the source location and contaminant extent to allow risk

assessment and remedial alternative evaluation.

After completing fieldwork, the Data Manager will organize analytical laboratory data for

evaluation, validation, and presentation. The organized data allows easy review for data

completeness. Data validation involves a comprehensive review of the laboratory data to verify

conformance with quality controls; qualifiers flag any deficient data to alert data users of

possible quality concerns. Tables organize all validated data, identifying the detected

contaminants, frequency and range of detections, and statistically representative contaminant

levels.

Data reviewers compare the maximum detected soil and groundwater contaminant levels to the

published risk-based screening criteria for each site. The EPA RSLs evaluate potential human-

health risk concerns and the NOAA SQuiRTs values identify potential ecological risk drivers.

Volatile and extractable petroleum hydrocarbons, which are not cited by either reference, are

evaluated against GEPA ESLs (Guam EPA, 2008).

7.2 RESTORATION ACTIVITIES APPROACH

Due to the intrusive nature of the removal action, the first order of business includes identifying

and locating the pipelines, valves, and associated equipment at the Roi-Namur POL Yard. Each

of the necessary steps following these activities are outlined below in the following sections.



7.2.1 Supplemental Data Collection

All field work pertaining to the supplemental data collection described in Section 5.0 is outlined

in the work plan addendum to the 2010 Sivuniq work plan (Sivuniq, 2011).

Data collected during this supplemental mobilization, as well as that collected during the original

SI mobilization, will be used as a baseline for removal action/remediation efficiency.

7.2.2 Subsurface Modeling and Design Finalization

After collection of supplemental data, subsurface modeling of contaminant fate and transport

will be conducted, along with modeling for oxygen and nutrient dispersal for the

sparging/injection wells. Final designs will be developed based on the results of this modeling,

with revision of the remedial approach implemented if subsurface conditions indicate that the

current approach is not feasible.

7.2.3 Construction of Infiltration Galleries

Trenching will occur continuously until all infiltration tile is installed. Dig permits and utility

locates will be completed prior to initiation. Clean overburden will be stockpiled near the site, so

that it can be used as backfill once the infiltration tile has been laid in the trench. A trench box

will be used to hold up each trench, with infiltration tile installed under it. After the tile is laid

down, a porous material (gravel) will be overlain, and then clean backfill will fill the trench. As

this is happening, the trench box will be moved as the trench is extended until the trench is

completed. Contaminated soil will be moved to a landfarming cell for treatment. The entire site

area will be restricted using hard barriers against unwanted access during construction of the

infiltration galleries (as required by the UES).

Infiltration galleries will be installed based on the final designs that are developed for the

removal and remedial action work plan.

7.2.4 Installation of NAPL Extraction Equipment

After the first few trenches are excavated, the extraction equipment will be concurrently installed

to ensure system startup occurs promptly. Trenches will consist of porous material outside an

infiltration drain that is wrapped with hydrophobic material. After the trenches have been



installed, the belt skimmer will be installed in at least the center of the length of the trench

(depending on the final design).

Once the trench is complete, the equipment used for NAPL retrieval will be connected to the belt

skimmer, and also to the 55-gallon drums used for product storage and oil/water separation.

Drums will be located within secondary containment to ensure that accidental discharge does not

occur. The system will not be connected to the on-site power grid until it is ready for startup.

7.2.5 Infiltration Galleries System Startup

Once the first infiltration gallery has been installed, it will be connected to the on-site power grid

and made ready for startup. This will be conducted concurrently with the installation of other

infiltration galleries. Once the system has stabilized, efforts will be made to optimize NAPL

extraction and ensure that the system is working in an efficient manner. Any modifications made

to the design will be implemented for the other infiltration galleries that will be concurrently

installed.

7.2.6 NAPL Removal Monitoring and Operation

Once each system has stabilized, extraction will run in pulsed waves to allow the trench to

accumulate product between each removal event. This will also facilitate waste handling, as each

of these pulses will generate waste that can then be disposed of while the trench recharges. The

amount of water in the collected waste will be monitored to ensure that the belt skimming

operation is working as designed. The interval time between pulses will be determined by on-site

conditions, and most likely correspond to rain events (that would presumably create flow into the

infiltration galleries).

7.2.7 Contaminated Soil Landfarming

While the NAPL removal system is running, active landfarming of the excavated soil that was

contaminated will be conducted. Once all of the contaminated soil has been stockpiled, it will be

spread out over a liner so that the total thickness is approximately 1 foot. Nutrients will be

supplemented during start-up, and also each time the soil is tilled. Tilling will occur on a regular

schedule twice per month. The landfarm cell will be covered unless it is being tilled, to prevent

runoff and wind erosion.



Contaminant concentrations will be monitored using PetroFLAG test kits or other petroleum

hydrocarbon screening methods. Once screening results indicate contaminant concentrations are

low enough for the soil to be used as fill material, multi-incremental sampling will be used to

confirm the final concentration of contaminants. The soil will be used to backfill the trenches if

possible.

7.2.8 NAPL Removal Verification Assessment and Reporting

Following the NAPL removal, a verification assessment shall be conducted to evaluate whether

hazards have been adequately mitigated to support enhanced bioremediation. The verification

assessment shall include sampling and analysis in consonance with the SAP and QAPP.

Per UES 3-6.5.8(i)(2), the verification assessment and accompanying findings and

recommendations shall be provided to the appropriate agencies, which shall have a period of 30

days for review and comment. If, in conjunction with/following the agency comment period,

USAKA determines that an unacceptable risk remains, removal actions shall be continued. In

circumstances where it is determined that the immediate hazards have been mitigated, all

supporting data and rationale shall be documented in a formal report which will be made

available for 30 days for public review and comment. The report will indicate which of two

possible courses of action is proposed: 1) the mitigation efforts are deemed complete and

effective, rendering a determination of NFA/RC, or 2) potential contamination remaining may be

addressed in a non-time critical manner via the remedial actions. Since the NAPL removal is not

intended to reduce contaminant concentrations below a concentration where unacceptable risk

remains (only immediate risk), remedial actions shall be conducted as described below.

7.2.9 Installation of Injection Wells

After the infiltration galleries have been installed, injection/sparging wells will be installed after

the trenches have been backfilled. Spacing will be based on contaminant modeling and site

conditions encountered, and will cover the area where de-oxygenation of groundwater has

occurred (indicating that groundwater and soil need amendments for further biodegradation to

occur). Wells will be installed upgradient of infiltration galleries, so that water extracted during

NAPL removal can be recirculated with nutrients and oxygen to recharge the aquifer. Initial



wells will be installed near the fringe of the contaminant plume, and additional wells installed

towards the center of the contaminant mass as NAPL is extracted by removal action activities.

7.2.10 Installation of Sparging Equipment and Pumps

After the first few wells are installed, sparging equipment and pumps will be installed on the

finished wells concurrently with the installation of the remaining wells. Nutrients will be

uniformly distributed throughout the site (in approximately 10% of the total number of wells),

and the wells used rotated through so that aeration and nutrient addition will not be found in

isolated areas.

7.2.11 Enhanced Bioremediation System Startup

Once the first injection/sparging well has been installed, it will be connected to the on-site power

grid and made ready for startup. This will be conducted concurrently with the installation of

other wells. After startup, and once the system has stabilized, efforts will be made to optimize

injection rates to ensure that the system is working in an efficient manner. Any modifications

made to the design will be implemented for the other injection wells that will be concurrently

installed. Nutrient requirements determined by contaminated soil landfarming will form the

baseline for enhanced bioremediation start-up activities.

7.2.12 Long-Term Monitoring

Air sparging will be performed continuously at flow rates necessary to keep DO concentrations

above 2 mg/L, based on site conditions encountered. Nutrients will be injected through wells on

a regular rotation schedule determined by site conditions. The objective will be to ensure that

aerobic biodegradation can occur at optimal levels.

Contaminant concentrations will be monitored in groundwater on a regular schedule throughout

the life of the removal action; soil concentrations will be monitored using soil borings on a less

frequent basis. Screening methods will be used to determine contaminant concentrations until

cleanup goals are attained. At this point, analytical confirmation samples will be collected to

verify the results of the screening. If confirmation sample results indicate that cleanup goals have

been attained, the remedial action will cease and the project will move into reporting.



7.2.13 Project Reporting

Following contaminant concentration reduction to below cleanup goals, verification sampling

and assessment shall be conducted to evaluate whether hazards have been adequately mitigated,

pursuant to 3-6.5.8(q). This effort shall ensure:

the collection of a representative number and type of samples requisite to determine the

effectiveness of the remedial action instituted;

the appropriate cleanup or alternative standards have been achieved; and

human health, safety, and the environment have been adequately protected and restored.

A detailed SAP shall be developed and followed for this stage.

After verification sampling and assessment actions have been adequately completed, a final

project evaluation will be performed pursuant to 3-6.5.8(r). All actions and assessment

findings/rationale shall be documented and provided to the public and the Appropriate Agencies.

The remediation project manager, in consultation with the Appropriate Agencies, shall make one

of three determinations from the verification assessment performed:

Termination of remediation and a designation of NFA/response complete;

Propose modification of the selected remedy via a modification to the Document of

Environmental Protection (DEP) or completion of a new DEP for the remedial action,

modifications to the proposed remedy could include long-term monitoring and/or

institutional controls in lieu of further remedial action; or

Propose repetition of the remedial action via a modification to the DEP.

Further actions will be conducted pursuant to the determination.

7.3 SAMPLING AND ANALYSIS PLAN

Contamination at the Roi-Namur POL Yard Spill site was generally delineated during the SI and

supplemental sampling activities. However, additional soil and groundwater sampling will be

required to confirm the extent of contamination prior to completion of the remedial design and

installation of the remediation system, as well as for long-term monitoring during the



implementation of the removal action. This section describes the sampling techniques and

methods to be used during these activities.

Visual assessments by the Field Team Leader prior to field sampling will identify surface

features, indications of contamination, or other conditions that may affect the effectiveness of the

proposed approach. Notable site features will be included in the data collection program, as

appropriate, to provide a comprehensive site investigation and support future remedial decision-

making.

Field activities include two phases of sampling – screening and confirmation. The sampling

objectives delineate the locations and extents of vapor and dissolved contaminant plumes, source

areas, and release points. Screening activities provide data to the field teams to identify

contaminant and source locations and direct field efforts. Indirect screening methods, such as

headspace vapor analysis, indicate secondary impacts from contaminants in soil and

groundwater. Direct screening measurements use infrared absorbance and turbidimetric methods

to quantify contaminants contained within the medium. Table 7-1 and Table 7-2 summarize

screening techniques for soil and groundwater, respectively. Although quality controls

procedures for screening techniques will be implemented, the data are typically qualitative or

semi quantitative in nature.

Table 7-1 Field Screening Methods for Soils

Parameter Method

Organic Headspace Vapors Physical Inspection (odor, etc.)

Photoionization Detector (PID)

Petroleum Product Sheen Screen Testing

Notes: 1 RaPIDAssay

TM Petroleum Fuels in Soil Field Test equipment provided by Strategic Diagnostics, Inc

2 PetroFLAG analyzer system provided by Dexsil Corporation

Table 7-2 Field Screening Methods for Water

Parameter Method

Organic Headspace Vapors Field Portable Gas Chromatography

Petroleum Product Sheen Screen Testing



The second sampling phase, confirmation sampling, provides high-quality data for decision-

making purposes. Utilizing a variety of quality control in the field and at the laboratory, these

data provide the basis for definitive site characterization, risk assessment, and remedial

evaluations. The laboratory analyses that will be performed for soil and water matrices are listed

in Table 7-3 and Table 7-4.

Table 7-3 Laboratory Analytical Methods for Soils

Parameter Analytical Method

Volatile Petroleum Hydrocarbons (VPHs) EPA Method 8260B Modified

Extractable Petroleum Hydrocarbons (EPHs) EPA Method 8015B Modified

Volatile Organic Compounds (VOCs) EPA Methods 8260B

Polycyclic Aromatic Hydrocarbons (PAHs) EPA Method 8270D-SIM

Bulk Density ASTM D2937-10

Particle Size Distribution ASTM D6913-04

Total Organic Carbon (TOC) EPA Method 9060

Table 7-4 Laboratory Analytical Methods for Water

Parameter Analytical Method

Volatile Petroleum Hydrocarbons (VPHs) EPA Method 8260B Modified

Extractable Petroleum Hydrocarbons (EPHs) EPA Method 8015B Modified

Volatile Organic Compounds (VOCs) EPA Method 8260B

Ethylene dibromide (EDB) EPA Method 8011

Polycyclic Aromatic Hydrocarbons (PAHs) EPA Method 8270D-SIM

Sample collection methods vary according to the media under investigation. Soil sampling

methods include the use of direct-push equipment, hand augers, and shovels. Field crews use

manual and direct-push equipment to install groundwater sample points; permanent, pre-packed

well points will be used to provide high quality data for monitoring.

Archeological and safety concerns characterize much of Roi-Namur Island; however, this risk is

limited at the Roi-Namur POL Yard Spill site because it is located almost entirely on post-WWII



dredge fill (since the disturbance caused by the filling operations would have likely detonated

any buried UXO). However, strict adherence to the USAKA dig permitting process will ensure

that artifacts and critical infrastructure remain protected and the worksite remains a safe

operation, even if the risk is low. Additionally, even though the proper authorities permit digging

and intrusive activities, Sivuniq field personnel must remain vigilant to the possibility of

inadvertent discoveries of artifacts, ordnance, or equipment during fieldwork.

Intrusive activities associated with soil and groundwater sampling shall be monitored by a

qualified archeological specialist implementing the AMP described in Section 7.6. Major

elements of the monitoring include GPS-positioning for all sample locations, inspection of

coring samples, and descriptive documentation of soil characteristics.

7.4 QUALITY ASSURANCE PROJECT PLAN

The QAPP addresses performance and measurement issues by identifying critical attributes and

assessment characteristics to evaluate degree of conformance to the project requirements.

Project performance characteristics generally evaluate qualitative aspects of work activities. The

measurement characteristics pertain to quantitative data and information elements.

The finalized QAPP will contain four sections to address key components of quality

management, and will be provided as part of the removal and remedial action work plan.

The Project Management section defines the project organization, roles and

responsibilities of key stakeholders, quality objectives/criteria, and recordkeeping

requirements.

The Measurement section prescribes the sampling process and methods, operating

procedures, audit schedule, and information management.

The Assessment and Oversight section details performance and technical audit systems,

data reporting, and corrective action reporting.

The Data Validation and Usability section provides scrutiny of output data to verify

appropriate uses.

The following subsections provide the planning level data quality objective parameters for the

proposed remediation projects. As the removal and remedial action work plan develops, critical



work elements will be identified and assessment criteria developed. These criteria will then

populate the bulk of the quality assurance plan for use during project execution. Furthermore, all

analytical data obtained will have quantitation limits set below developed target concentrations

(as described in Section 6.2.1), pursuant to UES 3-5.6.8(g)(1)(iii).

7.4.1 Data Quality Objectives

After fieldwork has been completed, the Data Manager will organize analytical laboratory data

for evaluation, validation and presentation. The organized data compiled for each media and

analysis group will be reviewed to assess data for completeness. Data validation will involve a

comprehensive review of the laboratory data to verify conformance with quality controls; any

deficient data will be qualified to alert data users of possible quality concerns. Validated data

will be organized into tables to identify detected contaminants, frequency and range of

detections, and statistically representative contaminant levels. Data validation memorandums

will be developed for each data group.

The validation focuses on the DQOs specified in the QAPP in terms of Data Quality Indicators

(DQIs), which include precision, accuracy, representativeness, comparability, sensitivity, and

completeness. The quality control (QC) parameters applied to evaluating each of the DQIs are

summarized in Table 7-5.



Table 7-5 Quality Control Parameters Corresponding to Data Quality Indicators

Data Quality Indicators QC Parameters

Precision

RPD values of:

(1) LCS/LCSD

(2) MS/MSD (or Laboratory Duplicate)

(3) Field Duplicates

Accuracy

%RPD, %R, or %D values of:

(1) Initial Calibration and Calibration Verification

(2) Surrogate Spikes

(3) Internal Standards

(4) Labeled Compounds

(5) LCS

(6) MS

Results of:

(1) Instrument and Calibration Blank

(2) Method (Preparation) Blank

(3) Trip Blank

Representativeness

(1) Results of All Blanks

(2) Sample Integrity

(3) Holding Times

Comparability

(1) Sample-specific LOQs

(2) Sample Collection Methods

(3) Laboratory Analytical Methods

Sensitivity Sample-specific LOQs

Completeness

(1) Data qualifiers

(2) Laboratory deliverables

(3) Requested/Reported valid results

Notes, Acronyms and Abbreviations:

%RSD Percent relative standard deviation

%R Percent recovery

%D Percent difference

%Df Percent drift

LCS Laboratory control sample

LCSD Laboratory control sample duplicate

MS Matrix Spike

MSD Matrix spike duplicate

PQL Practical quantitation limit

RPD Relative percent difference



7.4.1.1 Precision

Precision is defined as the degree of mutual agreement among independent measurements as the

result of repeated application of the same process under similar conditions. Analytical precision

is evaluated by the relative percent difference (RPD) values of laboratory control

sample/laboratory control sample duplicate (LCS/LCSD) and matrix spike/matrix spike duplicate

(MS/MSD) analyses. The RPD values of field duplicate analyses represent the combined

precision of sample collection and analysis procedures, as well as sample homogeneity.

7.4.1.2 Accuracy/Bias

Accuracy is a statistical measurement of correctness and includes components of random error

(variability due to imprecision) and systemic error. It is quantified as the degree of agreement

between a measurement with a known reference. Analytical accuracy is evaluated via the

percent recovery (%R), or percent difference (%D) values of initial and continuing calibration,

internal standards, surrogate spikes, MS/MSD, and LCS/LCSD in conjunction with method

blank, calibration blank, and trip blank results. Results of blanks assist in identifying the type

and magnitude of effects contributed to the system error introduced via field and/or laboratory

procedures.

7.4.1.3 Representativeness

Representativeness is the level of confidence that the analytical data reflect the actual field

condition. Representativeness is ensured by maintaining sample integrity during collection,

preparation, and analysis. The evaluation of associated method and field blanks also assists in

identifying artifacts that may skew the representativeness of the samples.

7.4.1.4 Comparability

Comparability describes the confidence with which one data set can be compared to another data

set measuring the same property. Methods used to assess and promote comparability of data

include blanks and use of standard methods. Using standard methods throughout the data

generation processes ensures the comparability of data generated in separate sampling days or

events.



7.4.1.5 Sensitivity

Sensitivity depicts the level of ability an analytical system (i.e., sample preparation and

instrumental analysis) of detecting a target component in a given sample matrix with a defined

level of confidence. Factors affecting the sensitivity of an analytical system include: analytical

system background (e.g., laboratory artifact or method blank contamination), sample matrix

(e.g., mass spectrometry ion ratio change, co-elution of peaks, or baseline elevation), and

instrument instability.

7.4.1.6 Completeness and Data Usability

Completeness is a measure of the amount of valid data obtained from a measurement system for

each method, analyte, and matrix. Completeness is calculated for the aggregation of data for

each analyte measured for any particular sampling event or other defined set of samples, and

reported for each method, matrix, and analyte combination. The number of valid results divided

by the number of possible individual analyte results, expressed as a percentage, determines the

completeness of the data set.

The requirement for completeness is 95% for all collected samples of a particular matrix. In the

case of samples that cannot be analyzed (because of holding time violations in which re-

sampling and analysis were not possible, samples spilled or broken, etc.), the numerator of this

calculation will be the number of valid results minus the number of possible results not reported.

7.5 SITE SAFETY AND HEALTH PLAN

The project SSHP addresses risks to personnel safety during work performance. The scope of

the SSHP includes regulatory, installation, and corporate requirements to ensure full protection

for project employees, stakeholders, and bystanders during work performance and remediation

operations.

The SSHP has two basic parts to provide general information for non-specific work hazards and

mitigation strategies to manage and control risk from specific risks derived from a job hazard

analysis. Table 7-6 provides a generalized job hazard analysis to be used as a planning-level

SSHP for the remediation projects under consideration. The SSHP is a “living document” that

grows and adapts to the project tasks as the work proceeds; routine maintenance of the document

provides job- and task specific hazard analyses and response to address new conditions. A

finalized SSHP will be delivered as an attachment to the removal and remedial action work plan.



Table 7-6 Hazard Analyses for General Jobsite Activities

Potential Hazards Precaution

Uneven, Unstable, Slippery

Terrain Use caution when moving about excavations, berms, and soil piles.

Slip, Trip, Fall Hazards Be aware of trip hazards at the worksite, and use suitable footwear for work in rough terrain.

Maintain good housekeeping for worksite areas.

Heavy Lifting Strains/Back

Injury

Use care when lifting heavy loads.

Proper lifting techniques include bending at the knees and using leg muscles or utilizing mechanical

lifting aids.

Pinching and Drop

Hazards

Do not place hands into tight spaces.

Use care when handling heavy tools.

Wear steel-toed boots, gloves, and eye protection to avoid injury to vulnerable body parts.

Inclement Weather Stop outdoor work during storms and seek shelter.

Exposure to Heat (Air and

Water)

Utilize appropriate hot-weather PPE such as cooling vests to aid natural body ventilation; these

devices add weight, so their use should be balanced against efficiency. Use portable showers or

hose-down facilities to reduce body temperature and cool protective clothing.

Heat Stress

Drink 16 ounces of water before beginning work. Water maintained at 50°F to 60°F should be

available. Under severe conditions, drink 1 to 2 cups every 20 minutes, for a total of 1 to 2 gallons

per day. Do not use alcohol or other nonalcoholic fluids in place of water . Decrease your intake of

coffee and caffeinated soft drinks during working hours to prevent dehydration.

Acclimate yourself by slowly increasing workloads (e.g., do not begin with extremely demanding

activities).

Avoid direct sun whenever possible, as it can decrease physical efficiency and increase the

probability of heat stress. Take regular breaks in a cool, shaded area. Use a wide-brim hat or an

umbrella when working under direct sun for extended periods. Wear sunscreen (SPF30 minimum) to

prevent sunburn.

Provide adequate shelter/shade to protect personnel against radiant heat (sun, flames, hot metal).

Observe one another for signs of heat stress. Persons who experience signs of heat syncope, heat

rash, or heat cramps should consult the Site Safety Supervisor to avoid progression of a heat-related

illness.

On-site Traffic Wear high-visibility clothing.

Avoid high-traffic areas.

Low Light Conditions No field work after dark.

Working Alone Use the buddy system.

Blood-borne Pathogens

Hepatitis B, human immunodeficiency virus (HIV), and other life-threatening diseases can be

transmitted by contact with body fluids of an infected individual. When rendering first aid to another

individual, avoid contact with bodily fluids.

Noise Wear hearing protection if you have to shout to be heard by someone 3 feet away.

Heavy Equipment

Operations

Clear sites for subsurface hazards such as underground utilities and UXO.

Observe equipment operation during excavation – stay 20 feet from overhead power lines.

If UXO are suspected stop all activity, evacuate to a safe location and call Kwajalein fire

department.

Stay away from operating equipment.

Working area to be defined to exclude pedestrians.

Review equipment operation including kill switch locations.

Be aware of moving parts.

Wear hearing protection if noise levels exceed permissible exposure limits of 85 dBA.

Working Around Heavy

Equipment and Drill Rig

Operations

Stay alert.

Make sure the operator knows you are there.

Wear high-visibility vests and other required PPE.

Use hand signals to communicate with equipment operator

Wear ear protection

Trenches/Excavations

Do not enter any trenches or excavations. This plan does not cover excavation safety (OSHA

1926.650-.652), as this work will be performed by subcontractors.

Stay 4 feet from the sidewall of any exaction or trench over 4 feet deep.

Munitions and Unexploded

Ordnance

Attend orientation training to understand nature and identification of hazard

Approach all investigation activities with caution



The finalized SSHP will provide information related to roles and responsibilities, routine and

emergency procedures, hazard classes, and generic mitigation strategies. The project manager,

field team leader, and site safety coordinator each play key roles in the plan application. All

work performers share responsibility to work safely and can shut down operations if unsafe

conditions occur. Practiced routine and emergency procedures will be enacted to ensure that

personnel know proper safety operation and response protocols. The physical, chemical, and

biological hazards for each task activity will be identified along with one or more engineering

controls or mitigation strategies.

7.6 ARCHAEOLOGICAL MONITORING PLAN

The purpose of the AMP is to define a structured plan for the identification and documentation of

potential cultural resources during the activities related to the contaminated sites investigation. A

CRE has been completed which outlines the results of the background research and previous

archaeological investigations within the areas of potential effect for the proposed construction.

The CRE has determined that some portions of the Environmental Investigations Activities as

Potential Contamination Sites at USAKA has limited potential to destroy, damage, or alter

known and hitherto previously unidentified cultural resources that would qualify for the RMI

List of Cultural and Historic Places under criteria a, d, e, and/or k as defined in the UES (2011:

3-7.6.4).

The five aspects of this project have been defined to have a potential to effect sub-surface

cultural resources, if present. These include:

1. Soil sampling

2. Groundwater sampling

3. Excavations

The area described for remediation in this RAM has little or no probability of effects to cultural

resources, because the area is located exclusively atop dredge fill material. Therefore, no

archaeological monitoring is required.

Should sampling or other excavations encounter artifacts, remains or any other archaeological

resources in locations where monitoring is not required, work will stop. The archaeologist will be

followed; these procedures will be included in the removal and remedial action work plan.



8.0 REFERENCES

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