engineering a sustainable future draft bioremediation bench ...nh-3423-2012-d nobis engineering,...

NH-3423-2012-D Nobis Engineering, Inc.

Draft Bioremediation Bench-Scale Test Technical Memorandum Eastern Surplus Company Site Meddybemps, Maine Long-Term Response Action EPA Task Order No. 0005-RA-LR-0189 REMEDIAL ACTION CONTRACT No. EP-S1-06-03 FOR

US Environmental Protection Agency Region 1 BY

Nobis Engineering, Inc. Nobis Project No. 80005 January 2012

Nobis Engineering, Inc. Lowell, Massachusetts

Concord, New Hampshire

Phone (800) 394-4182 www.nobisengineering.com

U.S. Environmental Protection Agency Region 1 5 Post Office Square, Suite 100 Boston, Massachusetts 02109-3919

Engineering a Sustainable Future


Draft Bioremediation Bench-Scale Test Technical Memorandum Eastern Surplus Company Site Meddybemps, Maine Long-Term Response Action EPA Task Order No. 0005-RA-LR-0189 REMEDIAL ACTION CONTRACT No. EP-S1-06-03 For US Environmental Protection Agency Region 1 By Nobis Engineering, Inc. Nobis Project No. 80005 January 2012

Scott W. Harding, P.E. David W. Gorhan Senior Project Manager Project Scientist


Nobis Engineering, Inc. | New Hampshire | Massachusetts

Client-Focused, Employee-Owned

www.nobiseng.com

Nobis Engineering, Inc.18 Chenell DriveConcord, NH 03301T (603) 224-4182

Nobis Engineering, Inc.585 Middlesex StreetLowell, MA 01851T (978) 683-0891

EPA Region 1 RAC 2 Contract No. EP-S1-06-03 January 25, 2012 Nobis Project No. 80005 U.S. Environmental Protection Agency, Region 1 Attention: Mr. Terry Connelly, Task Order Project Officer 5 Post Office Square, Suite 100, HBO Boston, Massachusetts 02109-3919 Subject: Transmittal of the Draft Bioremediation Bench-Scale Test Technical Memorandum Eastern Surplus Company Site, Meddybemps, Maine Long-Term Response Action Task Order No. 0005-RA-LR-0189 Dear Mr. Connelly: Enclosed for EPA’s review is the Draft Bioremediation Bench-Scale Test Technical Memorandum for the Site. This submittal was identified in the approved Work Plan Amendment No. 3 dated July 1, 2011. Should you have any questions or comments, please contact me at (603) 724-6235, or [email protected]. Sincerely, NOBIS ENGINEERING, INC. Scott W. Harding, P.E. Senior Project Manager Enclosure

Via Electronic Submittal


TABLE OF CONTENTS DRAFT BIOREMEDIATION BENCH-SCALE TEST TECHNICAL MEMORANDUM

EASTERN SURPLUS SUPERFUND SITE MEDDYBEMPS, MAINE

SECTION PAGE

NH-3423-2012-D i Nobis Engineering, Inc.

An Employee-Owned Company

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

2.0 CURRENT SITE CONDITIONS ................................................................................. 1

3.0 BENCH-SCALE TEST PROCEDURES AND RESULTS ........................................... 6 3.1 Bedrock Borehole Exploration and Sampling .................................................... 6 3.2 Bench-Scale Test Procedures ........................................................................... 8 3.3 Potential Metals Mobilization ............................................................................. 9

4.0 CONCLUSIONS AND RECOMMENDATIONS ........................................................ 10 4.1 Conclusions .................................................................................................... 10 4.2 Recommendations .......................................................................................... 11

TABLES NUMBER

1-1 Contaminants of Concern 2-1 Spring 2011 Groundwater Field Parameter Measurements 2-2 Fall 2011 Groundwater Field Parameter Measurements 2-3 Spring 2011 Groundwater Monitoring Results – Metals 2-4 Fall 2011 Groundwater Monitoring Results - Metals 2-5 Spring 2011 Groundwater Monitoring Results – VOCs 2-6 Spring 2011 Groundwater VOC Exceedances Detected by Aquifer Zone 2-7 Fall 2011 Groundwater Monitoring Results – VOCs 2-8 Fall 2011 Groundwater VOCs Exceedances Detected by Aquifer Zone 2-9 Historical Trends of PCE Concentrations

FIGURES NUMBER

1-1 Locus Plan 2-1 Site Plan with Aquifer Zones 2-2 Spring 2011 Northern Bedrock PCE Concentration Distribution 2-3 Fall 2011 Northern Bedrock PCE Concentration Distribution 2-4 PCE Concentrations Over Time in Select Northern Bedrock Monitoring Wells

APPENDICES

- ------ · ------ --- - ,_ ------------ -- - -- -- ---- ·- -------- - - --


APPENDIX

A Boring Logs/Borehole Construction Details B BCI Bench-Scale Test Report

NH-3423-2012-D 1 Nobis Engineering, Inc.

1.0 INTRODUCTION

Nobis Engineering, Inc. (Nobis) has prepared this Technical Memorandum (Tech Memo) to

summarize the current Site conditions, document the results of the bioremediation bench-scale

test, and evaluate the feasibility of performing an in situ bioremediation pilot study at the Eastern

Surplus Company Site (Site) located in Meddybemps, Maine. A Site locus plan is included as

Figure 1-1. This work was performed in accordance with the U.S. Environmental Protection

Agency (EPA) Region I Remedial Action Contract 2 (RAC 2) No. EP-S1-06-03, Task Order No.

0005-RA-LR-0189.

The Long-Term Response Action (LTRA) implements the remedies selected in the

September 2000 EPA Record of Decision (ROD) to address the Site contamination and threats

to human health and the environment posed by groundwater contamination. Since 2001, EPA

has been operating a groundwater pump and treat system to remediate concentrations of

chlorinated volatile organic compounds (VOCs) present in bedrock groundwater.

Bioremediation is being considered as a “polishing” technology to remediate the relatively low-

level residual contamination above the Interim Groundwater Cleanup Levels (IGCLs) and

Project Limits (PL; for surface water) for the contaminants of concern (COCs) specified in the

Record of Decision (EPA, 2000). During an August 18, 2010 meeting with EPA, State of Maine

Department of Environmental Protection (MEDEP), and Nobis, the team decided that a bench-

scale test was necessary to determine whether this technology was feasible at the Site prior to

considering implementation of an in situ bioremediation pilot study. Site COCs are listed in

Table 1-1.

The objective of this Technical Memorandum is to document the tasks associated with the

bench-scale test and to evaluate the results of the bench-scale test, along with data collected

during the previous 5 years, to determine the feasibility of performing an in situ bioremediation

pilot study.

2.0 CURRENT SITE CONDITIONS

The following is a summary of the current conditions at the Site. Subsurface data and

interpretation is extracted from historical reports prepared by Nobis and is focused on the

Northern Plume aquifer zone. A Site Plan with aquifer zones is included as Figure 2-1. Nobis

has not performed intrusive subsurface investigation at the Site under the current Task Order


with the exception of two boreholes drilled for the purpose of the bench-scale test (discussed in

in Section 3.1).

The concentrations of COCs in groundwater within the Southern Plume have been observed to

be at or near the MEG/MCLs since 2008. Based on the historical results, Nobis (with the

approval of the EPA and MEDEP) ceased operation of the extraction and treatment of

groundwater in the Southern Plume area in November 2010. The most recent round of

groundwater samples collected by Nobis in the Southern Plume area (Spring 2011) did not

indicate that significant contaminant concentration rebound had occurred in the aquifer zone.

During the May 2011 groundwater monitoring round, the maximum PCE concentration was

4.7 µg/L, detected in a groundwater sample collected from MW-50S. The next monitoring round

is scheduled for May 2012.

The current conditions in the Northern Plume area are summarized below:

Bedrock and aquifer characteristics recorded during the boring activities, low-flow purging and

monitoring are summarized below:

• The top of the bedrock surface has been observed 7 feet below ground surface (bgs) at

MW-54B and MW-55B. The overburden unit is generally found to be seasonally dry

during treatment system operation and contain mostly fill following the NTCRA

excavations previously performed. Limited overburden recharge is observed during the

spring monitoring rounds likely due to the snow melt; however, during the late summer

and fall of each year minimal groundwater is observed in the overburden monitoring

wells screened to the approximate bedrock surface.

• During the period when the treatment system was offline, August 2006 through

September 2007, the shallow bedrock and overburden aquifer units recharged to static

conditions. PCE concentrations increased in the overburden monitoring wells

significantly suggesting that as the water table rose through the previously dewatered

shallow bedrock fractures non-aqueous phase liquid (NAPL) residual contamination

began to back-diffuse into the aquifer. Following approximately one year of treatment

system operation, each of the aquifer units (overburden, shallow bedrock, and deep

bedrock) returned to conditions consistent with those observed prior to the 2006

shutdown in both elevation and PCE concentrations as reported in the Draft 2006


Annual Data Summary, prepared by Tetra Tech, NUS. Groundwater elevations were

observed under static water table conditions when the treatment system was offline in

August 2007 to be at approximately 2.5 feet below those when the system was

operational for an extended period of time (greater than 2 years).

• Recharge rates noted during the collection of groundwater samples in several of the

bedrock wells is below 100 milliliter per minute (mL/min) and monitoring wells have to be

evacuated during groundwater sampling and allowed to recharge for at least 24 hours to

attain 70% of the initial water level.

Geochemical parameters recorded during low-flow purging and monitoring from the Spring 2011

round are included in Table 2-1 and Fall 2011 round are included in Table 2-2. A summary of

the measurements collected from shallow bedrock monitoring wells is included below:

• During low-flow purging of the monitoring wells within the Northern Plume flowpath

dissolved oxygen concentrations ranged from 0.42 milligrams per liter (mg/L) to 9.89

mg/L in the Spring 2011 round and 0.33 mg/L to 7.09 mg/L in the Fall 2011 round. Due

to the use of inertial lift pumps to evacuate certain monitoring wells, some DO readings

are recorded at elevated concentrations and may not be fully representative of the actual

aquifer conditions. Given the well diameters and depths; however, inertial lift pumps are

the best method of evacuating the wells to allow for complete water column recharge

and for collecting samples. Other less disturbing methods have been tested at the Site

including peristaltic and bladder pumps, but they do not have the lifting force required for

the deeper monitoring wells.

• Oxidation-reduction potential (ORP) measurements ranged from -199.3 millivolts (mV) to

+159.2 mV in the Spring 2011 round and from -201.2 mV to +232.5 mV in the Fall 2011

round. During both rounds each of the wells indicated positive ORP values with the

exception of MW-51B. The newly installed wells located within 20 feet upgradient and

downgradient of MW-51B indicated positive ORP during the Fall 2011 round, suggesting

that the negative ORP at MW-51B may be an anomaly or related to a phenomena in the

well construction. Negative ORP values generally indicate reducing conditions required

for anaerobic bioremediation while positive values often indicate that oxygen is likely

present in some form.

• pH ranged from 6.61 to 12.71 in the Spring 2011 round and from 5.59 to 13.02 in the

Fall 2011 round. Generally, pH values lie between the neutral range of 6.0 and 8.0.


Aquifers in this range are generally very suitable for supporting bacterial growth;

however, the addition of electron-donors can cause significant decreases in pH requiring

a buffering agent to bring the aquifer back into a neutral range to maintain a suitable

condition for bioremediation. Elevated pH readings are observed in the core of the

Northern Plume area and are generally associated with monitoring wells MW-35B1R,

MW-51B, MW-54B, and MW-55B. The source of the alkaline water (pH>7) remains

unknown, but without a known source of alkali, poor well construction can be a

contributing factor. It is possible that the Portland cement-bentonite mixture used in the

rock-socket seal(s) did not properly set up. Portland cement is highly alkaline and if the

product dissolves it could affect the water in and around the monitoring wells.

• Conductivity ranged from 96 micro-Siemens per square centimeter (µS/cm2) to 6,604

µS/cm2 in the Spring 2011 round and from 64 µS/cm2 to 6,037 µS/cm2 in the Fall 2011

round. The maximum recorded conductivities are consistently observed at MW-35B1R.

The remaining wells generally exhibit conductivities below 1,000 µS/cm2.

• Turbidity measurements were generally below 5 Nephelometric turbidity units (NTUs)

following low-flow purging of the monitoring wells during both of the monitoring rounds.

Turbidity was elevated in monitoring wells which required the use of inertial lift pumps

and complete well evacuation prior to sampling. The movement of the inertial lift pump

tends to stir sediments within the water column.

• Temperature recorded during the low-flow purging during each of the monitoring rounds

appeared to be related to seasonal climatic fluctuations.

• Nobis performed field tests in June 2008 for the presence of residual permanganate

remaining in the groundwater from the 2003 ISCO treatment. Seven locations were

selected for the field test: MW-42S, IN-4B, IN-6B, MW-48S, and MW-32S plus the

influent north and south locations within the treatment plant. The locations were

selected to cover each aquifer unit. Residual permanganate was not observed in any of

the samples at concentrations over 0.3% (detection limit of the test). Additionally, purge

water and sample volumes are visually observed for purple tints and black particles that

would suggest that residual permanganate and/or manganese exist in the aquifer. No

evidence of residual permanganate or byproducts has been observed since Nobis began

work at the Site in 2007.


Metals concentrations in the northern plume area in the upper bedrock aquifer unit during the

Spring 2011 and the Fall 2011 groundwater sampling round are included in Tables 2-3 and 2.4,

respectively, and were used to develop the following conclusions.

• Samples for the total TAL metals and mercury were collected from the LTM monitoring

wells during the Spring 2011 round (summarized in Table 2-3). Analyses were

performed for total metals and, therefore, the samples were not filtered in the field. Five

metals were detected in the groundwater samples at concentrations above the

MEG/MCLs. Aluminum was detected in four wells ranging from 1.3 to 2 times the MEG

of 1,430 µg/L. Antimony was detected in one well at 2.3 times the MCL of 6 µg/L.

Arsenic was detected in six wells ranging from 1.5 to 3 times the MCL of 10 µg/L. Lead

was detected in one well at 1.5 times the MCL of 15 µg/L (MEG is 20 µg/L). Manganese

was detected in four wells ranging from 1.4 to 4.3 times the MEG of 200 µg/L.

• Samples for the dissolved TAL metals and mercury were collected from the LTM

monitoring wells during the Fall 2011 round (summarized in Table 2-4). Analyses were

performed for dissolved metals and, therefore, the samples were filtered in the field

using 0.45 micron inline filter. Six metals were detected in the groundwater samples at

concentrations above the MEG/MCLs. Aluminum was detected in one well at 4.3 times

the MEG of 1,430 µg/L. Antimony was detected in one well at 3 times the MCL of 6

µg/L. Arsenic was detected in five wells ranging from 1 to 2.5 times the MCL of 10 µg/L.

Arsenic was also detected in a surface water background sample collected by MEDEP in

November 2011 at 2.5 times the MCL. Beryllium was detected in one well at 1 times the

MCL of 4 µg/L (concentration was 4.1 µg/L). Lead was detected in one well at 1.3 times

the MCL of 15 µg/L (MEG is 20 µg/L). Manganese was detected in two wells ranging

from 2.1 to 2.4 times the MEG of 200 µg/L. Manganese was also detected in three of

the porewater samples collected by MEDEP in November 2011 at 1 to 6.5 times the

MEG.

Plots of PCE concentrations in the northern plume area in the upper bedrock aquifer unit during

the Spring 2011 and the Fall 2011 groundwater sampling round are included in Figures 2-2 and

2.3, respectively, and were used to develop the following conclusions.

• Samples for VOCs were collected from the LTM monitoring wells during the Spring 2011

round (summarized in Tables 2-5 and 2-6). Two VOCs; PCE and TCE were detected in

the groundwater samples at concentrations above the MEG/MCLs. PCE was detected


in 15 wells ranging from 3 to 600 times the MEG of 3 µg/L. TCE was detected in 3 wells

ranging from 1.3 to 1.7 times the MEG of 5 µg/L. All other results were below the MEG.

• Samples for VOCs were collected from the LTM monitoring wells during the Fall 2011

round (summarized in Tables 2-7 and 2-8). Two VOCs; PCE and TCE were detected in

the groundwater samples at concentrations above the MEG/MCLs. PCE was detected

in 19 wells ranging from 2 to 367 times the MEG of 3 µg/L. TCE was detected in 1 well

at 2 times the MEG of 5 µg/L. All other results were below the MEG.

• Historical VOC trends are summarized in Table 2-9 and on Figure 2-4.

3.0 BENCH-SCALE TEST PROCEDURES AND RESULTS

The bench-scale test was conducted to evaluate the efficacy of bioremediation using samples of

site groundwater and sediment so that an evaluation of the feasibility of bioremediation could be

made for this site. In order to determine the feasibility of bioremediation at a site, three factors

need to be addressed: 1. Do favorable site conditions exist for bioremediation or can favorable

conditions be achieved through a bioaugmentation process; 2. Are the correct species of

microbes present to metabolize the contaminants; and 3. Can the required amendments be

delivered and distributed to the treatment zone effectively and efficiently to ensure that the

residual NAPL is contacted and degraded as designed.

In order to collect the data with which to evaluate the first two criteria, Nobis contracted with

Bioremediation Consulting, Inc. (BCI) of Watertown, Massachusetts to perform a bench-scale

test using Site groundwater and sediment. If, based on the results of the bench-scale tests,

moving forward with the pilot program is approved, the third question will be further addressed

in a pilot test design document to be prepared by Nobis (with the assistance of a qualified

subcontractor (e.g., BCI).

3.1 Bedrock Borehole Exploration and Sampling

Nobis contracted with Maine Test Boring (MTB) of Hermon, Maine to advance two bedrock

borings that were completed as temporary monitoring wells. The intent of the borings was to

obtain bedrock cores and sediment from the leading and trailing edges of the core of the


Northern Plume. The cores/sediment would be used in conjunction with groundwater obtained

from the open boreholes to perform the bench-scale test.

The borings were advanced between September 6, 2011 and September 9, 2011. The

locations of the borings are shown on Figure 2-1. Each boring was drilled to a depth of 14 to

16 feet bgs where the casing was set and grouted into the bedrock using a Portland cement and

bentonite grout mixture. The grout was allowed to set for nearly 24 hours before coring work

commenced. Bedrock coring techniques were used to advance the borings to a depth of 47 feet

bgs. Refer to the boring logs included in Appendix A for more details.

The bedrock cores returned each showed significant fracturing, both mechanical and natural, so

it is possible that the bedrock unit in which the rock socket was set contained additional

pathways to the surface.

The bedrock borings were completed as open boreholes that may be used as possible injection

points and/or monitoring wells during the pilot test. The boreholes were constructed in a

manner which would allow for future completion in several different configurations.

Each of the boreholes was developed following completion of coring activities by over-purging

using a Whale submersible pump to remove water and silt. Development water was transferred

to the treatment plant and transferred to the equalization tanks then processed through the

treatment train. Sediment was drummed and stored in the treatment plant along with cuttings

generated during the drilling activities.

Nobis returned to the Site to obtain groundwater samples using specialized containers provided

by BCI to ensure that representative samples would be used in the bench-scale test. The

containers included two 40 mL VOA vials preserved with hydrochloric acid (HCl) for

groundwater, 3 unpreserved VOA vials for groundwater, two 1 liter serum bottles for

groundwater with a reducing agent, and one 160 mL serum bottle for sediment per location.

The serum bottles required special filling and capping procedures to ensure that the samples

were maintained in an anaerobic state. The reducing agent in the bottles remained black upon

arrival at BCI indicating the samples were still in a reducing state. Additionally, selected

segments of the rock cores obtained from the drilling activities were aerobically packaged and

sent to BCI along with the groundwater and sediment samples.


3.2 Bench-Scale Test Procedures

BCI received the samples and determined that each set had arrived in adequate conditions for

the test. BCI contacted Nobis with the preliminary characterization data to determine which

sample would be selected for the bench-scale test. It was determined that due to the higher

PCE concentration and slightly more negative ORP value in the sample collected from MW-55B

than in the sample collected from MW-54B, the sample from MW-55B would be selected for the

test. Both samples were determined to have a relatively high pH for bedrock groundwater

(greater than pH 9), but considering the potential grout seal problems, the high pH could be a

result of the Portland cement grout impacting the water in and around the well.

BCI set up the controlled bench-scale test with 5 separate microcosms:

• Microcosm #1 contained the “killed control”; the pH was lowered to pH 2 to eliminate

biological activity.

• Microcosm #2 contained the “unamended control”; the microcosm received no

amendments or adjustments to see if ambient groundwater conditions could naturally

support dechlorination.

• Microcosm #3 contained amendments of minerals and electron donors.

• Microcosm #4 contained amendments of minerals and electron donors in addition to

bioaugmentation with BCI’s proprietary culture of Dhc.

• Microcosm #5 contained a duplicate of Microcosm #4.

The bench-scale tests were performed for a total of 49 days, after which time 95 percent to 100

percent of the PCE was dechlorinated to ethene in Microcosms #4 and #5. The test results

suggest that complete dechlorination from PCE to ethene can be achieved using Site

groundwater, an electron donor (e.g., vegetable oil), and the BCI proprietary culture of

Dehalococcoides (Dhc). It was concluded that the native groundwater was not capable of

performing the necessary processes to carry out dechlorination without amendments and

bioaugmentation because Microcosms #1 through #3 did not indicate any PCE dechlorination

through the 49 days test period. For a full discussion of the bench-scale test procedures and

results refer to the Final Report, Laboratory Anaerobic Microcosm Study with Groundwater from

MW-55B at the Eastern Surplus Company Superfund Site in Meddybemps, ME, to Investigate


Anaerobic Dechlorination of PCE and Removal of Metals during Anaerobic Treatment and

Review of Literature on Fate of Metals Under Anaerobic Conditions, prepared by BCI and

provided in Appendix B.

3.3 Potential Metals Mobilization

There is potential in any organic biodegradation process for mobilization of metals in the aquifer

due to changes in the groundwater geochemistry resulting from the treatment process. Of

particular concern at this site are arsenic and manganese, which are both regularly detected in

the influent water of the treatment system. BCI performed a literature review of the potential for

the biodegradation process to mobilize metals, potentially resulting in regulatory exceedances in

the Dennys River surface water.

BCI examined the concentrations of four metals specifically: aluminum, arsenic, lead, and

manganese, as these metals are historically the most likely to exceed the MEGs at the Site.

Based on the literature review, it appears that the solubility of aluminum would be expected to

increase under anaerobic conditions; but the solubility of lead, manganese, and arsenic would

be expected to decrease. The microcosm tests appear to confirm this (or better). The

laboratory data collected during the study suggests that in microcosms which supported

reductive dechlorination (Microcosm #4 and #5 which were bioaugmented and which best

simulate conditions expected during the pilot test), each of these metals precipitated out of

solution when treated, resulting in reduced concentrations in supernatant liquid (i.e.

groundwater). This result suggests the field application of the bioaugmentation amendments

would not result in an increase in metals concentrations in groundwater.

Even with the results of the bench-scale tests suggesting metals will not be mobilized by the in

situ bioremediation process, all metals would be contained and monitored during the pilot-test, if

conducted. The recirculation system, as part of the pilot test, discussed in BCI’s report (Figure

1) would contain the flow and transport of soluble metals to the Dennys River. Following

completion of the pilot-test, the existing extraction well array and treatment system could be

restarted to contain the metals if they persisted.

--


4.0 CONCLUSIONS AND RECOMMENDATIONS

4.1 Conclusions

The objective of this Technical Memorandum is to document the tasks associated with the

bench-scale test and to evaluate the results of the bench-scale test, along with data collected

during the previous 5 years, to determine the feasibility of performing an in-situ bioremediation

pilot-study in the Northern Plume area.

Two bedrock boreholes were installed to obtain groundwater, bedrock, and sediment samples

for the bench-scale test. The boreholes were installed along the leading and trailing edges of

the core of the plume and to a depth of approximately 47 feet bgs.

Bench-scale test samples were delivered to BCI, who conducted the tests. BCI used the

groundwater and sediment sample from MW-55B to run a 49 day bench-scale test. The test

results suggest that complete dechlorination from PCE to ethene can be achieved using Site

groundwater, an electron donor (e.g., vegetable oil), and the BCI proprietary culture of Dhc.

Other control microcosms did not indicate any significant dechlorination without

bioaugmentation and stimulation.

BCI examined aluminum, arsenic, lead, and manganese concentrations to evaluate impacts to

their mobility once the aquifer is adjusted to a reducing condition. Based on the literature

review, it appears that the solubility of aluminum would increase under anaerobic conditions; but

the solubility of lead, manganese, and arsenic would be expected to decrease. This research

was confirmed by the test, with the exception that aluminum was determined to become less

soluble under anaerobic conditions. The laboratory data collected during the study suggests

that in microcosms which supported reductive dechlorination, each of these metals precipitated

out of solution when treated, resulting in reduced concentrations in supernatant liquid (i.e.

simulated groundwater).

Figure 1 of the BCI report illustrates the conceptual layout of the pilot test recirculation system.

In essence, injection wells will be located near MW-53B and MW-34B1/2 with extraction and

recirculation wells located near the existing extraction well array, and monitoring locations in

between. Existing monitoring and extraction wells may be able to be modified for use in the

pilot test program.


4.2 Recommendations

Based on the conclusions presented above, Nobis makes the following recommendations:

• The bench-scale test indicated positive results supporting the theory that the Site will

support in situ bioremediation including the application of an electron-donor (e.g.,

vegetable oil), Dhc stimulation, and pH buffering. Based on this data, Nobis

recommends performance of the pilot-scale test program. A conceptual design

document including estimated costs, volumes, and schedule should be completed. A

modification to the current Statement of Work would be required to complete the

document.

• The treatment would contain a recirculation loop so that the amended water would

migrate through the core of the Northern Plume area and be recovered and further

amended ex situ. This recirculation would reduce the chance that mobilized metals,

namely aluminum, would reach the Dennys River, should they be mobilized by the

altered geochemical conditions.

• Monitoring downgradient of the Northern Plume core would be required to determine if

additional hydraulic capture will be necessary. Monitoring would include groundwater

sample collection and laboratory analysis for VOCs, metals, and geochemical

parameters. If additional capture is required, the existing Site treatment system could be

restarted and operated to more effectively contain groundwater with elevated

concentrations of VOCs and metals. Up to two additional monitoring wells would be

required downgradient of the existing extraction well array to perform the required

monitoring.

Table 1-1Groundwater Contaminants of Concern

Eastern Surplus Company SiteMeddybemps, Maine

NH-3423-2012 Nobis Engineering, Inc.

1,1,2-Trichloroethane 3 µg/L3 MEG4

Trichlorethene 5 µg/L MCL5

Tetrachloroethene (PCE) 3 µg/L MEG

Chloromethane 3 µg/L MEG

Methylene Chloride 5 µg/L MCL

Total polychlorinated biphenyls (PCBs) 0.05 µg/L MEG

bis (2-Ethylexyl) phthalate 6 µg/L MCL

cis-1,2-Dichloroethene 70 µg/L MCL/MCLG6

Manganese 200 µg/L MEG

Antimony 6 µg/L MCL/MCLG

Cadmium 5 µg/L MCL/MCLG

Lead 15 µg/L ROD PL

Xylenes (Total) 600 µg/L MEG

1,1-Dichloroethane 5 µg/L MEG

Aluminum 87 ug/L ROD PL

Arsenic ROD PL

Barium 4 ug/L ROD PL

Lead 0.5 ug/L ROD PL

Silver 0.36 ug/L ROD PLNotes:

1. Based on 2000 Record of Decision (ROD)2. IGCL = Interim Groundwater Cleanup Level3. µg/L = micrograms per liter4. MEG – 1992 Maine Maximum Exposure Guidelines5. MCL – Federal Maximum Contaminant Level: EPA 816-F-02-013 (July 2002)6. MCLG - Federal Maximum Contaminant Level Goal

Groundwater

Surface Water

Contaminant of Concern1 ROD IGCL2 Units Basis

I I I I I

Table 2-1Spring 2011 Groundwater Field Parameter Measurements


Page 1 of 2


Sample ID SampleLocation Sample Type Initial

DTW (feet)GW Elevation

(ft. MSL)Pump Type

SampleDate

SampleTime

Purge Rate(mL/min)

Temperature(°C)

Conductivity(μS/cm2)

pH ORP(mV)

Dissolved Oxygen(mg/L)

Turbidity(NTU)

ESLT-GW-IN1B1-0511 IN-1B1 Field Sample 8.30 172.12 Peristaltic 5/11/2011 14:50 115 8.26 128 6.54 0.4 103.90 0.76




ESLT-GW-IN3B-0511 IN-3B Field Sample 9.44 173.34 Peristaltic 5/10/2011 11:55 100 7.98 334 7.30 6.4 159.20 1.63

ESLT-GW-IN4B-0511 IN-4B Field Duplicate 01 11.70 171.44 Peristaltic 5/9/2011 16:20 125 7.82 523 7.02 4.7 221.20 1.59

ESLT-GW-DUP01-0511 IN-4B Field Duplicate 01 11.70 171.44 Peristaltic 5/9/2011 16:30 125 7.82 523 7.02 4.7 221.20 1.59



ESLT-GW-IS1B-0511 IS-1B Field Sample 6.46 158.74 Peristaltic 5/10/2011 12:45 125 7.51 342 8.40 0.6 -128.70 13.1

ESLT-GW-IS1S-0511 IS-1S Field Sample 7.05 159.46 Peristaltic 5/11/2011 15:40 250 7.73 485 5.73 8.3 278.30 0.73

ESLT-GW-IS2B-0511 IS-2B Field Sample 12.20 158.33 Peristaltic 5/10/2011 10:00 225 8.02 246 9.97 0.7 175.00 8.24

ESLT-GW-IS2S-0511 IS-2S Field Sample 11.90 160.21 Peristaltic 5/12/2011 11:40 200 8.05 374 5.86 8.5 229.70 0.77

ESLT-GW-MW18S-0511 MW-18S Field Sample 14.53 161.32 Peristaltic 5/11/2011 9:40 220 6.94 92 6.30 10.1 200.80 0.75

ESLT-GW-MW20B-0511 MW-20B Field Sample 10.93 169.83 Peristaltic 5/11/2011 16:30 220 7.13 91 6.13 9.8 184.60 1.55

ESLT-GW-MW23B-0511 MW-23B* Field Sample 9.23 168.15 Peristaltic 5/12/2011 9:45 100 8.64 290 7.99 6.2 229.50 0.55





ESLT-GW-MW34B1-0511 MW-34B1 Field Duplicate 04 8.42 172.8 Peristaltic 5/12/2011 10:25 100 8.27 93 6.21 7.1 183.00 0.85

ESLT-GW-DUP04-0511 MW-34B1 Field Duplicate 04 8.42 172.8 Peristaltic 5/12/2011 10:35 100 8.27 93 6.21 7.1 183.00 0.85

ESLT-GW-MW34B2-0511 MW-34B2 Field Sample 8.31 172.9 Peristaltic 5/11/2011 13:25 150 9.24 319 7.79 3.0 95.90 0.4

ESLT-GW-MW35B-0511 MW-35B Field Sample 15.81 -- Pneumatic 5/12/2011 13:30 -- 8.11 183 6.88 8.5 150.90 --

ESLT-GW-MW35B1R-0511 MW-35B1R Field Sample 13.15 168.23 Peristaltic 5/12/2011 11:10 100 7.77 6604 12.71 8.3 -72.40 1.56

Table 2-1Spring 2011 Groundwater Field Parameter Measurements


Page 2 of 2


Sample ID SampleLocation Sample Type Initial

DTW (feet)GW Elevation

(ft. MSL)Pump Type

SampleDate

SampleTime

Purge Rate(mL/min)

Temperature(°C)


pH ORP(mV)

Dissolved Oxygen(mg/L)

Turbidity(NTU)

ESLT-GW-MW36B1-0511 MW-36B1* Field Sample 13.11 156.98 Inertial Lift 5/12/2011 13:00 600 8.79 272 8.45 9.9 179.00 25.1

ESLT-GW-MW36B2-0511 MW-36B2* Field Sample 11.47 158.71 Inertial Lift 5/12/2011 9:45 700 9.07 264 9.71 0.2 26.90 49.1

ESLT-GW-MW3B-0511 MW-3B Field Duplicate 03 6.75 173 Peristaltic 5/11/2011 11:00 190 7.23 69 6.35 3.3 155.00 0.68

ESLT-GW-DUP03-0511 MW-3B Field Duplicate 03 6.75 173 Peristaltic 5/11/2011 11:05 190 7.23 69 6.35 3.3 155.00 0.68

ESLT-GW-MW41B1-0511 MW-41B1* Field Sample 21.42 155.38 Inertial Lift 5/11/2011 11:00 300 8.44 216 7.51 8.6 125.70 341

ESLT-GW-MW41B2-0511 MW-41B2 Field Sample 3.05 173.82 Peristaltic 5/10/2011 14:55 110 7.71 237 7.69 0.7 -102.10 0.71

ESLT-GW-MW42B2-0511 MW-42B2* Field Sample 32.66 145.73 Inertial Lift 5/10/2011 17:10 140 8.31 164 8.95 4.1 -32.80 4.12

ESLT-GW-MW42SB-0511 MW-42SB Field Sample 7.87 171.54 Peristaltic 5/10/2011 16:05 100 6.67 86 5.67 2.1 194.50 1.92

ESLT-GW-MW43B1-0511 MW-43B1* Field Sample 26.99 151.34 Inertial Lift 5/11/2011 14:40 400 8.91 219 8.09 5.7 143.30 5.51ESLT-GW-MW43B2-0511 MW-43B2* Field Sample 9.42 169.05 Inertial Lift 5/11/2011 14:05 200 8.47 384 8.84 141 3.31 1000ESLT-GW-MW43S-0511 MW-43S Field Sample 11.17 169.09 Peristaltic 5/10/2011 16:30 170 6.78 125 5.72 212.3 6.48 0.49ESLT-GW-MW44S-0511 MW-44S Field Duplicate 02 11.81 165.96 Peristaltic 5/10/2011 16:40 100 6.50 92 5.75 79.4 9.53 1.16

ESLT-GW-DUP02-0511 MW-44S Field Duplicate 02 11.81 165.96 Peristaltic 5/10/2011 16:45 100 6.50 92 5.75 79.4 9.53 1.16


ESLT-GW-MW49S-0511 MW-49S* Field Sample 5.80 158.54 Peristaltic 5/12/2011 13:00 100 10.40 201 6.29 179.6 9.35 40.2


ESLT-GW-MW50S-0511 MW-50S Lab QC 12.07 157.43 Peristaltic 5/11/2011 12:05 200 7.70 263 6.01 256.8 8.39 0.37

ESLT-GW-MW51B-0511 MW-51B Field Sample 8.9 171.05 Peristaltic 5/12/2011 13:55 100 9.11 2006 12.20 -199.3 0.72 0.5

ESLT-GW-RW1-0511 RW-1 Lab QC 6.65 172.58 Peristaltic 5/10/2011 10:20 230 7.30 56 5.74 209.8 1.47 0.57

Notes:

1. "NA" indicates not applicable, "DRY" indicates a dry well and a sample was not collected.2. * indicates that the well draws down under minimal purging rates and that the well was evacuated completely and allowed to recharge for a minimum of 12 hours prior to sampling. :3. ft. MSL = feet above mean sea level4. mL/min = milliliters per minute5. μS/cm2 = microSiemens per cubic centimeter6. mV = millvolts7. mg/L = milligrams per liter8. NTU = Nephelometric Turbidity Units

Table 2-2Fall 2011 Groundwater Field Parameter Measurements


Page 1 of 2


Sample ID SampleLocation Sample Type

InitialDTW(ft.)

GW Elevation(ft. MSL)

Pump Type

SampleDate

SampleTime

Purge Rate

(mL/min)

Temperature(°C)


pH ORP(mV)

DissolvedOxygen(mg/L)

Turbidity(NTU)

ESLT-GW-IN1B1-1111 IN-1B1 Field Sample 10.62 169.80 Peristaltic 11/8/2011 13:30 100 12.64 95 5.99 220.3 0.43 0.50ESLT-GW-IN1B2-1111 IN-1B2 Field Sample 17.50 162.90 Peristaltic 11/8/2011 15:15 100 10.35 179 8.96 211.8 0.57 0.25ESLT-GW-IN2B1-1111 IN-2B1 Field Sample 13.91 166.72 Peristaltic 11/9/2011 14:50 100 11.70 107 6.11 194.1 2.01 0.93ESLT-GW-IN2B2-1111 IN-2B2 Field Sample 17.68 162.97 Peristaltic 11/10/2011 8:55 100 9.85 331 8.02 203.4 0.51 0.09ESLT-GW-IN3B-1111 IN-3B Field Sample 12.70 170.08 Peristaltic 11/8/2011 14:00 100 11.88 286 6.65 142.6 2.07 0.22ESLT-GW-IN4B-1111 IN-4B Field Sample 14.73 168.41 Peristaltic 11/9/2011 15:55 100 10.61 425 7.31 179.1 2.03 0.89ESLT-GW-IN6B-1111 IN-6B Field Sample 9.60 171.02 Peristaltic 11/8/2011 11:30 180 11.84 107 6.61 -12.3 0.39 4.01ESLT-GW-IN7B-1111 IN-7B Field Sample 12.16 168.21 Peristaltic 11/9/2011 13:25 160 10.97 97 6.13 187.2 0.48 3.02ESLT-GW-MW14B-1111 MW-14B Field Sample 12.61 -- Inertial Lift 11/10/2011 13:25 400 10.39 550 6.28 78.7 7.33 9.81ESLT-GW-MW1B-1111 MW-1B* Field Sample 37.21 164.35 Inertial Lift 11/10/2011 14:30 NA 10.59 256 8.04 127.2 -- 20.40ESLT-GW-MW20B-1111 MW-20B Field Sample 15.75 165.01 Peristaltic 11/10/2011 11:05 100 12.39 100 6.29 178.3 2.08 6.45ESLT-GW-MW23B-1111 MW-23B* Field Sample 11.91 165.47 Peristaltic 11/10/2011 8:15 100 10.12 295 8.31 185.6 1.50 2.11ESLT-GW-MW27B-1111 MW-27B Field Sample 8.10 172.41 Peristaltic 11/8/2011 15:15 100 12.51 89 5.64 167.5 0.55 4.07ESLT-GW-MW34B1-1111 MW-34B1 Field Duplicate 02 10.51 170.71 Peristaltic 11/8/2011 10:00 160 12.93 64 5.59 183.7 2.79 1.00ESLT-GW-FD02-1111 MW-34B1 Field Duplicate 02 10.51 170.71 Peristaltic 11/8/2011 10:05 160 12.93 64 5.59 183.7 2.79 1.00ESLT-GW-MW34B2-1111 MW-34B2 Field Sample 11.37 169.84 Peristaltic 11/8/2011 11:05 180 10.53 278 7.60 160.2 1.09 1.00ESLT-GW-MW35B-1111 MW-35B Field Sample -- -- Pneumatic 11/10/2011 11:00 100 11.67 304 6.35 232.5 5.23 9.68ESLT-GW-MW35B1R-1111 MW-35B1R Field Sample 14.05 167.33 Peristaltic 11/8/2011 12:10 80 13.66 6037 13.02 28.6 7.11 3.11ESLT-GW-MW36B1-1111 MW-36B1* Field Sample 14.94 155.15 Inertial Lift 11/9/2011 11:00 750 Dry Before Readings Could be TakenESLT-GW-MW36B2-1111 MW-36B2* Field Sample 15.58 154.60 Inertial Lift 11/9/2011 10:20 750 9.67 183 9.75 -40.4 3.19 58.10ESLT-GW-MW3B-1111 MW-3B Lab QC 11.74 168.01 Peristaltic 11/9/2011 14:35 100 12.27 165 7.13 84.0 0.43 3.44ESLT-GW-MW41B1-1111 MW-41B1* Field Sample 24.68 152.12 Inertial Lift 11/10/2011 9:45 750 12.06 223 6.88 8.10 194.00ESLT-GW-MW41B2-1111 MW-41B2 Field Sample 4.55 172.32 Peristaltic 11/10/2011 12:00 120 9.68 232 7.23 -99.8 1.26 0.70ESLT-GW-MW42B2-1111 MW-42B2 Field Duplicate 01 32.74 145.65 Inertial Lift 11/9/2011 15:10 200 9.69 174 8.89 -54.3 0.58 8.67ESLT-GW-FD01-1111 MW-42B2 Field Duplicate 01 32.74 145.65 Inertial Lift 11/9/2011 15:15 200 9.69 174 8.89 -54.3 0.58 9

Table 2-2Fall 2011 Groundwater Field Parameter Measurements


Page 2 of 2


Sample ID SampleLocation Sample Type

InitialDTW(ft.)

GW Elevation(ft. MSL)

Pump Type

SampleDate

SampleTime

Purge Rate

(mL/min)

Temperature(°C)


pH ORP(mV)

DissolvedOxygen(mg/L)

Turbidity(NTU)

ESLT-GW-MW43B1-1111 MW-43B1* Field Sample 32.74 145.59 Inertial Lift 11/9/2011 11:50 100 10.96 50 8.00 49.6 5.19 7.01ESLT-GW-MW43B2-1111 MW-43B2* Field Sample 15.40 163.07 Inertial Lift 11/9/2011 12:30 300 11.52 323 8.73 69.8 6.15 1000.00ESLT-GW-MW43S-1111 MW-43S Field Sample 17.15 163.11 Peristaltic 11/9/2011 9:40 100 11.37 161 5.65 214.0 2.18 1.93ESLT-GW-MW4B-1111 MW-4B Field Sample 16.2 160.93 Peristaltic 11/9/2011 12:35 80 11.18 225 6.21 62.3 0.43 0.67ESLT-GW-MW4S-1111 MW-4S Field Sample 15.2 161.48 Peristaltic 11/9/2011 10:50 100 256.00 256 6.25 144.6 1.28 0.14ESLT-GW-MW51B-1111 MW-51B Field Sample 10.84 169.11 Peristaltic 11/10/2011 11:30 100 11.76 1721 12.22 -201.2 0.37 1.92ESLT-GW-MW54B-1111 MW-54B Field Sample 11.35 Note 9 Peristaltic 11/10/2011 10:15 100 11.60 179 9.64 138.4 0.33 4.88ESLT-GW-MW55B-1111 MW-55B Field Sample 11.45 Note 9 Peristaltic 11/10/2011 9:15 90 11.13 588 11.73 96.3 0.45 16.20ESLT-GW-RW1-1111 RW-1 Lab QC 7.30 171.04 Peristaltic 11/8/2011 10:05 200 13.76 46 5.88 171.3 1.62 0.70ESLT-GW-PW201-1111 PW-201 Field Sample NA NA Unknown 11/7/2011 14:00 NA NA NA NA NA NA NAESLT-GW-PW202-1111 PW-202 Field Sample NA NA Unknown 11/7/2011 15:15 NA NA NA NA NA NA NAESLT-GW-PW203-1111 PW-203 Field Sample NA NA Unknown 11/8/2011 8:30 NA NA NA NA NA NA NAESLT-GW-PW204-1111 PW-204 Field Duplicate 03 NA NA Unknown 11/8/2011 9:25 NA NA NA NA NA NA NAESLT-GW-FD03-1111 PW-204 Field Duplicate 03 NA NA Unknown 11/8/2011 9:30 NA NA NA NA NA NA NAESLT-GW-SW201-1111 SW-201 Field Duplicate 04 NA NA Unknown 11/8/2011 13:10 NA NA NA NA NA NA NAESLT-GW-FD04-1111 SW-201 Field Duplicate 04 NA NA Unknown 11/8/2011 13:15 NA NA NA NA NA NA NAESLT-GW-SW202-1111 SW-202 Field Sample NA NA Unknown 11/8/2011 12:05 NA NA NA NA NA NA NAESLT-GW-SW203-1111 SW-203 Field Sample NA NA Unknown 11/8/2011 11:45 NA NA NA NA NA NA NAESLT-GW-SW204-1111 SW-204 Field Sample NA NA Unknown 11/8/2011 11:10 NA NA NA NA NA NA NAESLT-GW-SWBK1-1111 SW-BK1 Field Sample NA NA Unknown 11/8/2011 14:20 NA NA NA NA NA NA NAESLT-GW-SWBK2-1112 SW-BK2 Field Sample NA NA Unknown 11/8/2011 0.61 NA NA NA NA NA NA NA

Notes:1. "NA" indicates not applicable, "DRY" indicates a dry well and a sample was not collected. 5. μS/cm2 = microSiemens per cubic centimeter2. * indicates that the well draws down under minimal purging rates and that the well was evacuated completely 6. mV = millivolts evacuated completely and allowed to recharge for a minimum of 12 hours prior to sampling. 7. mg/L = milligrams per liter3. ft. MSL = feet above mean sea level 8. NTU = Nephelometric Turbidity Units 4. mL/min = milliliters per minute 9. Installed September 2011; not yet surveyed.

Table 2-3Spring 2011 Groundwater Monitoring Results - MetalsEastern Surplus Company SiteMeddybemps, MainePage 1 of 3


CHEMICAL NAME CRQL MCL MEG-1992Aluminum 200 NA 1,430 129 J 332 81.4 J 230 162 J 167 J 164 J 139 J 107 J 228 100 J 157 J 210 105 J 101 J 191 J 158 J 130 JAntimony 2 6 NA 0.32 J 2.4 0.37 J 0.96 J 0.27 J 0.15 J 0.18 J 0.14 J 0.31 J 2 U 2 U 0.22 J 2 U 0.11 J 0.83 J 1.5 J 1.1 J 2 UArsenic 1 10 NA 4.4 14.9 4 6.8 4.1 3 2.8 3.1 4.5 2.8 4.3 7.3 2.5 3.3 4.6 5.3 4.5 4.3Barium 200 2,000 1,500 200 U 48.7 J 200 U 48.6 J 200 U 200 U 200 U 200 U 200 U 200 U 200 U 200 U 50.3 J 200 U 200 U 47.7 J 200 U 200 UBeryllium 5 4 NA 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 UCadmium 1 5 5 1 U 1 U 1 U 0.027 J 1 U 1 U 0.02 J 1 U 1 U 0.025 J 0.11 J 1 U 1 U 1 U 1 U 1 U 0.031 J 1 UCalcium 5,000 NA NA 13,300 8,550 9,920 10,200 60,400 91,800 93,600 9,170 8,380 12,800 17,600 2,380 J 20,900 10,200 11,100 32,100 12,800 6,620Chromium 10 100 100 10 U 3.7 J 10 U 3.8 J 1.2 J 1.8 J 1.8 J 10 U 10 U 10 U 1.8 J 1.3 J 3.2 J 10 U 10 U 10 U 10 U 10 UCobalt 50 NA NA 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 UCopper 25 1300 NA 25 U 25 U 25 U 25 U 25 U 25 U 25 U 25 U 25 U 25 U 25 U 25 U 25 U 25 U 25 U 25 U 25 U 25 UIron 100 NA NA 100 U 100 U 100 U 100 U 66.3 J 53.4 J 76.1 J 6,880 594 628 100 U 1280 51.8 J 100 U 100 U 100 U 100 U 48.9 JLead 10 15 20 10 U 1 J 10 U 10 U 1.5 J 3 J 2.2 J 1.1 J 10 U 10 U 10 U 0.96 J 1.4 J 10 U 10 U 2.6 J 1.6 J 10 UMagnesium 5,000 NA NA 2,860 J 1,030 J 1,790 J 1,740 J 3,980 J 7,810 8,020 1,960 J 1,650 J 5,860 5,560 249 J 7,280 2,410 J 1,580 J 7,810 1,670 J 1,400 JManganese 15 NA 200 123 85.1 6.3 J 59.3 37.6 39.9 41.7 867 52.8 102 77.3 65.3 4.2 J 15.4 4.8 J 2.2 J 15 U 15.8Mercury 0.2 2 2 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 UNickel 40 NA 150 40 U 40 U 40 U 40 U 40 U 40 U 40 U 40 U 40 U 40 U 40 U 40 U 40 U 40 U 40 U 40 U 40 U 40 UPotassium 5,000 NA NA 716 J 2,100 J 556 J 1,740 J 997 J 1,680 J 1,720 J 913 J 634 J 1,600 J 1,570 J 1,680 J 1,970 J 522 J 538 J 2,030 J 674 J 399 JSelenium 5 50 10 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 USilver 10 NA 50 10 U 10 U 0.56 J 10 U 0.97 J 10 U 10 U 1.1 J 1.1 J 0.58 J 10 U 10 U 2.3 J 10 U 0.77 J 10 U 0.9 J 0.87 JSodium 5,000 NA NA 7,250 28,000 5,210 59,300 5,370 7,990 8,200 5,770 7,940 41,800 60,600 42,800 31,600 4,640 J 4,770 J 15,400 5,420 3,310 JThallium 1 2 0.4 1 U 1 U 1 U 1 U 1 U 1 U 1 U 1 U 1 U 1 U 1 U 1 U 1 U 1 U 1 U 1 U 1 U 1 UVanadium 50 NA NA 50 U 6.7 J 50 U 2.2 J 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 3.6 J 50 U 50 UZinc 60 NA NA 60 U 60 U 60 U 60 U 60 U 60 U 60 U 60 U 60 U 60 U 60 U 60 U 60 U 60 U 60 U 60 U 60 U 60 U

Notes:1. All concentrations listed in micrograms per liter (µg/L). 2. U = below detection limit, J = quantitation approximate3. MCL=Federal Maximum Contaminant Level, MEG=1992 State of Maine Maximum Exposure Guidelines, CRQL=Contract Required Quantitation Limit.4. Bold and shaded text indicates can exceedance of the MCL and/or MEG.5. EPA Region 1 Tier I validation consists of checking for data package completeness and that performance evaluation sample limits are within reporting limits6. Metals antimony, arsenic, cadmium, lithium, selenium, and thallium were analyzed per ICP-MS; all other metals were analyzed per ICP-AES.

SAMPLE LOCATION IN-1B1 IN-3B IN-4B IN-4BIN-1B2 IN-2B1 IN-2B2

ESLT-GW-IN1B2-0511

Sample Date 11-May-11 12-May-11 11-May-11 12-May-11 10-May-11

ESLT-GW-IN6B-0511

ESLT-GW-IN7B-0511

ESLT-GW-IS1B-0511

Dilution Factor 1 1 1 1/2 1 19-May-11 9-May-11

1

STATION ID ESLT-GW-IN1B1-0511

ESLT-GW-IN2B1-0511

ESLT-GW-IN2B2-0511

ESLT-GW-IN3B-0511

MW-23SIS-1S

ESLT-GW-IS1S-0511

1/211-May-1110-May-11 11-May-11 10-May-11

1 1 1

IN-6B IN-7B IS-1B MW-27B

ESLT-GW-MW23S-0511

1 1 1 1 1

ESLT-GW-MW27B-0511

110-May-11

111-May-11

IS-2B IS-2S MW-18S MW-20B MW-23B

ESLT-GW-IN4B-0511

ESLT-GW-DUP01-0511

10-May-11 12-May-11 11-May-11 11-May-11 12-May-11

ESLT-GW-IS2B-0511

ESLT-GW-IS2S-0511

ESLT-GW-MW18S-0511

ESLT-GW-MW20B-0511

ESLT-GW-MW23B-0511



CHEMICAL NAME CRQL MCL MEG-1992Aluminum 200 NA 1,430Antimony 2 6 NAArsenic 1 10 NABarium 200 2,000 1,500Beryllium 5 4 NACadmium 1 5 5Calcium 5,000 NA NAChromium 10 100 100Cobalt 50 NA NACopper 25 1300 NAIron 100 NA NALead 10 15 20Magnesium 5,000 NA NAManganese 15 NA 200Mercury 0.2 2 2Nickel 40 NA 150Potassium 5,000 NA NASelenium 5 50 10Silver 10 NA 50Sodium 5,000 NA NAThallium 1 2 0.4Vanadium 50 NA NAZinc 60 NA NA

Notes:1.2.3.4.5.6.

SAMPLE LOCATION

Sample DateDilution Factor

STATION ID

165 J 158 J 134 J 166 J 89.8 J 182 J 1,900 3,080 4,110 104 J 81.6 J 1,390 188 J 777 182 J 700 2,390 127 J0.1 J 0.17 J 0.69 J 0.75 J 0.24 J 1.2 J 4 U 13.9 1.6 J 0.73 J 0.72 J 0.67 J 0.11 J 0.11 J 0.72 J 1.1 J 0.31 J 2 U3.4 3.1 4.7 5.1 5.4 4.6 5 17.3 9.9 4.6 4.3 6.2 14.7 31 4.5 19 18 4.2200 U 200 U 47.4 J 47.9 J 200 U 47.9 J 76.3 J 111 J 76.1 J 200 U 200 U 80.2 J 200 U 200 U 200 U 10.1 J 31.3 J 200 U

5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.75 J 0.8 J 5 U 5 U 0.58 J 5 U 5 U 5 U 5 U 3.7 J 5 U1 U 0.059 J 1 U 1 U 1 U 1 U 2 U 0.1 J 0.21 J 1 U 1 U 0.26 J 1 U 1 U 0.031 J 0.051 J 0.2 J 1 U

13,500 29,200 10,600 10,600 46,400 26,900 4,700 J 13,800 12,800 6,980 4,690 J 16,300 10,300 4,020 J 6,240 10,700 23,300 14,5000.99 J 3.7 J 10 U 0.96 J 2.4 J 0.97 J 44.7 1.9 J 5.4 J 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U

50 U 50 U 50 U 50 U 50 U 50 U 17.9 J 6.7 J 4 J 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U 50 U25 U 25 U 25 U 25 U 25 U 25 U 25.8 25 U 5.6 J 25 U 25 U 25 U 25 U 25 U 25 U 25 U 25 U 25 U62 J 60.4 J 100 U 100 U 100 U 100 U 2,290 2,140 4,360 100 U 100 U 2,600 100 U 429 50.5 J 434 3,240 100 U10 U 10 U 10 U 10 U 0.95 J 0.99 J 1.4 J 8.9 J 7.7 J 10 U 1 J 7.9 J 2.1 J 10 U 10 U 2.6 J 22.5 10 U

6110 10,200 1,550 J 1,490 J 6,930 2,800 J 5,000 U 4,700 J 4,930 J 1,600 J 1,090 J 3,190 J 865 J 799 J 1,420 J 1,270 J 3,770 J 2,640 J10 J 1.8 J 40.2 28.5 46.7 1.9 J 1.3 J 442 139 4.7 J 4.8 J 272 74.2 23.3 52.8 140 647 1.9 J

0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U40 U 40 U 40 U 40 U 40 U 40 U 19.1 J 10.1 J 21 J 40 U 40 U 40 U 40 U 40 U 40 U 40 U 40 U 40 U

1,410 J 3,070 J 2,300 J 2,290 J 1,090 J 775 J 32,700 J 3,270 J 1,250 J 594 J 510 J 2,540 J 998 J 866 J 877 J 1,280 J 2,650 J 552 J5 U 5 U 5 U 5 U 5 U 5 U 4.2 J 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U

10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U 10 U 0.84 J 0.66 J10,900 41,200 4,230 J 4,370 J 11,700 5,010 31,100 J 45,500 45,400 4,190 J 2,820 J 32,200 41,800 33,500 5,620 39,000 72,700 4,450 J

1 U 1 U 1 U 1 U 1 U 1 U 2 U 0.052 J 1 U 1 U 1 U 0.062 J 1 U 1 U 1 U 1 U 1 U 1 U50 U 50 U 50 U 50 U 3.6 J 50 U 4.2 J 4.3 J 4.4 J 50 U 50 U 3.1 J 50 U 50 U 50 U 50 U 5.7 J 50 U60 U 60 U 60 U 60 U 60 U 60 U 386 28.4 J 38.5 J 60 U 60 U 17.5 J 60 U 60 U 60 U 60 U 31.7 J 60 U

All concentrations listed in micrograms per liter (µg/L). U = below detection limit, J = quantitation approximateMCL=Federal Maximum Contaminant Level, MEG=1992 State of Maine Maximum Exposure Guidelines, CRQL=Contract Required Quantitation Limit.Bold and shaded text indicates can exceedance of the MCL and/or MEG.EPA Region 1 Tier I validation consists of checking for data package completeness and that performance evaluation sample limits are within reporting limitsMetals antimony, arsenic, cadmium, lithium, selenium, and thallium were analyzed per ICP-MS; all other metals were analyzed per ICP-AES.

MW-35B MW-35B1R MW-36B1 MW-36B2 MW-3B MW-3BMW-30S MW-32S MW-34B1 MW-34B1 MW-34B2 MW-43SMW-41B1 MW-41B2 MW-42B2 MW-42SB MW-43B1 MW-43B2

ESLT-GW-MW41B1-0511

ESLT-GW-MW41B2-0511

ESLT-GW-MW42B2-0511

ESLT-GW-MW42SB-0511

ESLT-GW-MW43B1-0511

ESLT-GW-MW43B2-0511

ESLT-GW-MW35B-0511

ESLT-GW-MW35B1R-0511

ESLT-GW-MW36B1-0511

ESLT-GW-MW36B2-0511

ESLT-GW-MW3B-0511

ESLT-GW-DUP03-0511

ESLT-GW-MW43S-0511

1 1/10 1

ESLT-GW-MW30S-0511

ESLT-GW-MW32S-0511

ESLT-GW-MW34B1-0511

ESLT-GW-DUP04-0511

ESLT-GW-MW34B2-0511

1 1 11 1 1 1 1 1 1 1 1 1 1/2 111-May-11 11-May-11 12-May-11 12-May-11 11-May-11 11-May-11 10-May-11 10-May-11 10-May-11 11-May-11 11-May-1112-May-11 12-May-11 12-May-11 12-May-11 11-May-11 11-May-11 10-May-11



CHEMICAL NAME CRQL MCL MEG-1992Aluminum 200 NA 1,430Antimony 2 6 NAArsenic 1 10 NABarium 200 2,000 1,500Beryllium 5 4 NACadmium 1 5 5Calcium 5,000 NA NAChromium 10 100 100Cobalt 50 NA NACopper 25 1300 NAIron 100 NA NALead 10 15 20Magnesium 5,000 NA NAManganese 15 NA 200Mercury 0.2 2 2Nickel 40 NA 150Potassium 5,000 NA NASelenium 5 50 10Silver 10 NA 50Sodium 5,000 NA NAThallium 1 2 0.4Vanadium 50 NA NAZinc 60 NA NA

Notes:1.2.3.4.5.6.

SAMPLE LOCATION


STATION ID

160 J 155 J 292 875 111 J 129 J 857 2212 U 2 U 0.16 J 3.1 1.4 J 0.089 J 0.17 J 0.31 J

4.1 4 3.2 3.8 2.9 2.6 3.9 3.4200 U 200 U 21.7 J 55.8 J 200 U 200 U 68.4 J 200 U

5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U1 U 0.025 J 0.055 J 0.85 J 0.043 J 0.029 J 1 U 0.14 J

9,470 9,560 20,900 14,900 19,400 22,200 128,000 4,660 J10 U 10 U 10 U 2.4 J 10 U 3.8 J 10 U 10 U50 U 50 U 50 U 50 U 10.8 J 50 U 50 U 50 U25 U 25 U 25 U 25 U 25 U 25 U 25 U 25 U

100 U 100 U 214 990 100 U 100 U 1340 98.7 J1.6 J 1.2 J 10 U 3.7 J 10 U 1.9 J 10 U 10 U

1,660 J 1,690 J 3,880 J 6,240 1,740 J 7,780 5,000 U 1,260 J7.6 J 7.4 J 11.5 J 96.8 5 J 15 U 9.2 J 75.50.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U40 U 40 U 40 U 40 U 11.5 J 40 U 40 U 40 U

473 J 480 J 3,190 J 2,070 J 5,000 U 2,150 J 16,700 446 J5 U 5 U 5 U 5 U 5 U 5 U 3.8 J 5 U

1.2 J 0.99 J 1 J 10 U 1 J 10 U 10 U 10 U5,990 5,750 32,200 36,400 3,110 J 14,200 43,100 4,250 J

1 U 1 U 1 U 1 U 1 U 1 U 2 U 1 U50 U 50 U 50 U 50 U 50 U 50 U 17.1 J 50 U60 U 60 U 60 U 87 60 U 60 U 60 U 60 U

All concentrations listed in micrograms per liter (µg/L). U = below detection limit, J = quantitation approximateMCL=Federal Maximum Contaminant Level, MEG=1992 State of Maine Maximum Exposure Guidelines, CRQL=Contract Required Quantitation Limit.Bold and shaded text indicates can exceedance of the MCL and/or MEG.EPA Region 1 Tier I validation consists of checking for data package completeness and that performance evaluation sample limits are within reporting limitsMetals antimony, arsenic, cadmium, lithium, selenium, and thallium were analyzed per ICP-MS; all other metals were analyzed per ICP-AES.

MW-44S MW-51B RW-1MW-50SMW-4BMW-49SMW-45SMW-44S

ESLT-GW-RW1-0511

ESLT-GW-MW44S-0511

ESLT-GW-MW51B-0511

ESLT-GW-MW50S-0511

ESLT-GW-MW4B-0511

ESLT-GW-MW49S-0511

ESLT-GW-MW45S-0511

ESLT-GW-DUP02-0511

1111111-May-1111-May-1112-May-1110-May-1110-May-11

1 2 110-May-1110-May-11 12-May-11

Table 2-4Fall 2011 Groundwater Monitoring Results - MetalsEastern Surplus Company SiteMeddybemps, MainePage 1 of 2


CRQL MCL MEG-1992

20 NA 1430 11.1 J 1.5 J 2.1 J 59.6 54.9 1.8 J 28.3 98.2 555 15.8 J 30.9 52.5 6170 623 16.9 J 22 12.5 J 18.5 J 19.2 J2 6 NA 2 U 2 U 2 U 0.17 J 0.17 J 2 U 2 U 17.7 2 U 2 U 2 U 2 U 2 U 2 U 2 U 2 U 2 U 2 U 2 U1 10 NA 22 1.8 1 U 7.8 7.3 2.1 0.59 J 17.3 6.3 1 U 24.1 12.1 18.5 1.1 9.4 1 U 1.2 4.4 4.5

10 2000 1500 10 U 10 U 10 U 3.5 J 3.2 J 2.4 J 1.2 J 6.7 J 9 J 10 U 10 U 4.9 J 72.3 3.7 J 2.4 J 10 U 3 J 3.8 J 3.7 J5 4 NA 1 U 1 U 1 U 1 U 1 U 1 U 1 U 1 U 1 U 1 U 1 U 1 U 4.1 J 1 U 1 U 1 U 1 U 1 U 1 U

0.5 5 5 0.5 UJ 0.5 UJ 0.5 UJ 0.5 U 0.5 U 0.5 UJ 0.5 U 0.5 UJ 0.5 UJ 0.5 UJ 0.5 UJ 0.5 UJ 0.5 UJ 0.5 UJ 0.5 UJ 0.5 UJ 0.5 UJ 0.5 UJ 0.5 UJ500 NA NA 8,960 18,600 87,800 9,230 9,410 32,300 3,200 7,580 6,760 2,150 J 3,470 J 8,640 17,000 51,100 2,130 2,140 4,190 4,470 4,8202 100 100 2 U 2 U 2 U 0.23 J 0.096 J 2 U 2 U 2 U 2 U 2 U 2 U 2 U 2 U 2 U 2 U 2 U 2 U 2 U 2 U1 NA NA 1 U 1 U 1 U 0.15 J 0.073 J 1 U 1 U 1 U 1 U 1 U 1 U 0.19 J 1.8 1 U 1 U 1 U 1 U 1.1 1.22 1300 NA 1.3 J 0.81 J 1.3 J 0.53 J 0.56 J 1.5 J 0.12 J 1.2 J 0.99 J 1.3 J 2 U 0.99 J 7.4 2 U 0.81 J 1.6 J 1.9 J 2 U 0.89 J

200 NA NA 23.6 J 68.1 J 186 J 25.9 J 26 J 70.1 J 15 J 66.6 J 681 26.7 J 15.7 J 51 J 5470 103 J 2250 13.4 J 58.8 J 398 4870.5 15 20 0.69 U 0.5 U 0.5 U 0.14 J 0.24 J 0.5 U 0.12 J 0.5 U 1.8 0.5 U 0.5 U 0.5 U 20.7 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U500 NA NA 1280 3480 12900 640 610 8,220 24 J 2,150 872 529 284 J 1,390 3,390 179 J 525 519 702 1,040 1,1201 NA 200 11.1 6.4 487 23 24.1 2.7 0.27 J 13 48 3.7 J 11.9 J 13.1 424 0.5 J 294 7.2 203 1160 1300

0.2 2 2 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U1 NA 150 0.74 J 0.36 J 1.6 0.64 J 0.7 J 3.4 1 U 0.64 J 3 0.55 J 0.18 J 1.2 2.9 1.5 0.68 J 0.97 J 0.71 J 1.1 0.9 J

500 NA NA 643 1,260 1,530 2,000 1,990 2,340 1,390 2,150 705 289 J 763 1,400 3,430 2,960 412 J 254 J 278 J 375 J 371 J5 50 10 5 U 5 U 5 U 5 U 5 U 5 U 1.9 J 0.67 J 0.75 J 5 U 5 U 5 U 0.68 J 5 U 5 U 5 U 5 U 5 U 5 U

0.5 NA 50 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U500 NA NA 18,800 7,300 8,400 53,700 52,500 16,600 23,700 45,200 32,700 3,390 J 33,800 J 38,400 67,900 12,600 3,210 3,240 3,390 3,400 3,7400.5 2 0.4 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U5 NA NA 0.9 J 5 UJ 5 UJ 1.5 J 1.3 J 3.5 J 5 U 2 J 2.7 J 5 UJ 5 UJ 0.99 J 3.5 J 3.1 J 5 UJ 5 UJ 5 UJ 5 UJ 5 UJ2 NA NA 4.4 0.48 J 6.9 1.3 J 1.9 J 6 1.2 J 4.1 7.4 2.1 1.9 J 4.8 47.7 2 UJ 2.6 2.5 2.3 1.7 J 1.4 J

Notes:1. All concentrations listed in micrograms per liter (µg/L). 2. U = below detection limit, J = quantitation approximate3. MCL=Federal Maximum Contaminant Level, MEG=1992 State of Maine

Maximum Exposure Guidelines, CRQL=Contract Required Quantitation Limit.4. Bold and shaded text indicates can exceedance of the MCL and/or MEG.5. EPA Region 1 Tier I validation consists of checking for data package completeness

and that performance evaluation sample limits are within reporting limits.6. Mercury was analyzed per ICP-AES; all other metals were analyzed per ICP-MS.7. Samples were analyzed using CLP Mod 2203.0 (Lower CRQLs for Cd, Pb, Ag, and Tl)

06 Dec 1106 Dec 11 06 Dec 11

MW-26BMW-15B2 MW-15B2ESLT-GW-

MW26B-1211ESLT-GW-

MW15B2-1211ESLT-GW-

DUP03-1211

11 1Sample Date

Dilution Factor

Silver

Thallium

ZincVanadium

Sodium

11 1 110-Nov-1110-Nov-11 10-Nov-11 9-Nov-11 9-Nov-119-Nov-11

SAMPLE LOCATION

Aluminum

Arsenic

Beryllium

STATION ID

Antimony

CHEMICAL NAME

Selenium

Nickel

Manganese

Lead

Copper

Potassium

Calcium

Cobalt

Iron

Magnesium

Mercury

Chromium

Cadmium

Barium

MW-14BMW-1B MW-23B MW-36B1

ESLT-GW-MW14B-1111

ESLT-GW-MW1B-1111

ESLT-GW-MW23B-1111

ESLT-GW-MW36B1-1111

MW-36B2

ESLT-GW-MW36B2-1111

MW-3B MW-42B2 MW-42B2 MW-43B1 MW-43B2 MW-55B PW-201 PW-202 PW-203 PW-204 PW-204

ESLT-GW-MW3B-1111

ESLT-GW-MW42B2-1111

ESLT-GW-FD01-1111

ESLT-GW-MW43B1-1111

ESLT-GW-MW43B2-1111

ESLT-GW-MW55B-1111

ESLT-GW-PW201-1111

ESLT-GW-PW202-1111

ESLT-GW-PW203-1111

ESLT-GW-FD03-1111

ESLT-GW-PW204-1111

11 1 1 1 1 1 1 1 1 1 17-Nov-11 8-Nov-11 8-Nov-11 8-Nov-119-Nov-11 9-Nov-11 9-Nov-11 9-Nov-11 10-Nov-11 7-Nov-11

Table 2-4Fall 2011 Groundwater Monitoring Results - MetalsEastern Surplus Company SiteMeddybemps, MainePage 2 of 2


CRQL MCL MEG-199220 NA 14302 6 NA1 10 NA

10 2000 15005 4 NA

0.5 5 5500 NA NA2 100 1001 NA NA2 1300 NA

200 NA NA0.5 15 20500 NA NA1 NA 200

0.2 2 21 NA 150

500 NA NA5 50 10

0.5 NA 50500 NA NA0.5 2 0.45 NA NA2 NA NA

Notes:1.2.3.

4.5.

6.7.


Silver

Thallium

ZincVanadium

Sodium

SAMPLE LOCATION

Aluminum

Arsenic

Beryllium

STATION ID

Antimony

CHEMICAL NAME

Selenium

Nickel

Manganese

Lead

Copper

Potassium

Calcium

Cobalt

Iron

Magnesium

Mercury

Chromium

Cadmium

Barium

17.3 J 14.9 J 18.6 J 13.3 J 15.8 J 41.5 13.8 J2 U 2 U 2 U 2 U 2 U 2 U 2 U1 U 1 U 1 U 1 U 1 U 24.3 1 U

10 U 10 U 10 U 10 U 10 U 10 U 10 U1 U 1 U 1 U 1 U 1 U 1 U 1 U

0.5 UJ 0.5 UJ 0.5 UJ 0.5 UJ 0.5 UJ 0.5 UJ 0.5 UJ2,330 2,170 2,180 2,130 2,360 3,450 2,140

2 U 2 U 2 U 2 U 2 U 2 U 2 U1 U 1 U 1 U 1 U 1 U 1 U 1 U2 J 2 U 1.1 J 1.1 J 0.8 J 2 U 1.8 J

31.7 J 25.8 J 25.5 J 24.6 J 26.6 J 23.1 J 25.1 J0.51 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U529 520 527 517 536 302 J 519

4 3.3 3.6 3.3 3.3 11.9 3.80.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U 0.2 U

0.71 J 1 U 0.28 J 0.28 J 0.26 J 1 U 0.59 J390 J 268 J 283 J 271 J 308 J 770 279 J

5 U 5 U 5 U 5 U 5 U 5 U 5 U0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U

3,820 3,480 3,610 3,550 3,380 33,600 3,4300.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U

5 UJ 5 UJ 5 UJ 5 UJ 5 UJ 5 UJ 5 UJ8.8 0.6 J 2.4 1.1 J 6.8 0.94 J 2.9

All concentrations listed in micrograms per liter (µg/L). U = below detection limit, J = quantitation approximateMCL=Federal Maximum Contaminant Level, MEG=1992 State of Maine Maximum Exposure Guidelines, CRQL=Contract Required Quantitation Limit.Bold and shaded text indicates can exceedance of the MCL and/or MEG.EPA Region 1 Tier I validation consists of checking for data package completeness and that performance evaluation sample limits are within reporting limits.Mercury was analyzed per ICP-AES; all other metals were analyzed per ICP-MS.Samples were analyzed using CLP Mod 2203.0 (Lower CRQLs for Cd, Pb, Ag, and Tl)

8-Nov-1111 1 1 1 1

ESLT-GW-SWBK2-1111

SW-BK2SW-201 SW-204 SW-BK1

ESLT-GW-FD04-1111

ESLT-GW-SW201-1111

ESLT-GW-SW202-1111

SW-201 SW-202 SW-203

ESLT-GW-SW203-1111

ESLT-GW-SW204-1111

ESLT-GW-SWBK1-1111

18-Nov-118-Nov-118-Nov-11 8-Nov-11 8-Nov-11 8-Nov-11

Table 2-5Spring 2011 Groundwater Monitoring Results - VOCsEastern Surplus Company SiteMeddybemps, MainePage 1 of 2


SAMPLE LOCATION

STATION ID

CHEMICAL NAME CRQL MCL MEG-1992

1,1,1-Trichloroethane 0.5 200 200 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.061 J 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

1,1,2,2-Tetrachloroethane 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

1,1,2-Trichloro-1,2,2-trifluoroethane 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

1,1,2-Trichloroethane 0.5 5 3 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

1,1-Dichloroethane 0.5 NA 70 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

1,1-Dichloroethene 0.5 7 7 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

1,2,3-Trichlorobenzene 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

1,2,4-Trichlorobenzene 0.5 70 70 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

1,2-Dibromo-3-chloropropane 0.5 0.2 0.2 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

1,2-Dibromoethane 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

1,2-Dichlorobenzene 0.5 600 NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

1,2-Dichloroethane 0.5 5 5 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

1,2-Dichloropropane 0.5 5 5 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

1,3-Dichlorobenzene 0.5 NA 85 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

1,4-Dichlorobenzene 0.5 75 NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

1,4-Dioxane NA NA NA R 100 U 100 U R R R 100 U 100 U R

2-Butanone 5 NA 170 10 U 10 U 5 U 10 U 5 U 5 U 5 U 5 U 10 U 5 U 5 U 5 U 5 U 5 U 10 U 5 U 5 U 5 U 5 U 10 U 10 U 10 U 10 U

2-Hexanone 5 NA NA 10 U 10 U 5 U 10 U 5 U 5 U 5 U 5 U 10 U 5 U 5 U 5 U 5 U 5 U 10 U 5 U 5 U 5 U 5 U 10 U 10 U 10 U 10 U

4-Methyl-2-Pentanone 5 NA NA 10 U 10 U 5 U 10 U 5 U 5 U 5 U 5 U 10 U 5 U 5 U 5 U 5 U 5 U 10 U 5 U 5 U 5 U 5 U 10 U 10 U 10 U 10 U

Acetone 5 NA NA 11 15 B 5 U 14 B 5 U 5 U 3.9 J 5 U 8.1 J 5 U 5 U 5 U 4.5 J 5 U 11 5 U 5 U 5 U 5 U 10 16 B 16 B 8.5 J

Benzene 0.5 5 5 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Bromochloromethane 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Bromodichloromethane 0.5 80 NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Bromoform 0.5 80 NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Bromomethane 0.5 10 10 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Carbon disulfide 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Carbon tetrachloride 0.5 5 2.7 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Chlorobenzene 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Chloroethane 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Chloroform 0.5 80 NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Chloromethane 0.5 NA 3 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

cis-1,2-Dichloroethene 0.5 70 70 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 2.8 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 3.7 0.46 J 0.5 U 0.5 U 5 U 5 U 5 U 5 U

cis-1,3-Dichloropropene 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Cyclohexane 0.5 NA NA 5 U 0.88 J 0.5 U 0.83 J 0.5 U 0.5 U 0.16 JB 0.5 U 5 U 0.5 U 0.5 U 0.15 JB 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Dibromochloromethane 0.5 80 NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Dichlorodifluoromethane 0.5 NA 1050 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Ethylbenzene 0.5 700 700 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Isopropylbenzene 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

m,p-Xylene 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Methyl acetate 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Methyl tert-butyl ether 0.5 NA 50 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Methylcyclohexane 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Methylene chloride 0.5 5 48 5 U 5 U 0.23 JB 5 U 0.19 JB 0.39 JB 0.39 JB 0.21 JB 5 U 0.19 JB 0.24 JB 0.35 JB 0.18 JB 0.17 JB 5 U 0.5 U 0.37 JB 0.2 JB 0.5 U 5 U 5 U 5 U 5 U

o-Xylene 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Styrene 0.5 100 5 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Tetrachloroethene 0.5 5 3 42 120 18 45 1.9 0.5 U 0.5 U 2.1 55 2.8 3.3 4.5 4.2 1.8 29 42 D 45 D 4.6 1.9 0.98 J 24 24 1.3 J

Toluene 0.5 1000 1400 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

trans-1,2-Dichloroethene 0.5 100 70 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

trans-1,3-Dichloropropene 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Trichloroethene 0.5 5 5 5 U 5 U 0.5 U 2.9 J 0.5 U 0.5 U 0.5 U 0.53 1.4 J 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 3.2 1.5 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Trichlorofluoromethane 0.5 NA 2300 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

Vinyl chloride 0.5 2 0.15 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U

DILUTION FACTORSAMPLE DATE

Notes: 1. All concentrations listed in micrograms per liter (µg/L). 2. "D" = Diluted Result, "J" = Justified Result, "B" = Detected in Lab Blanks, "R"= Results Rejected, CRQL=Contract Required Quantitation Limit.3. MCL=Federal Maximum Contaminant Level, MEG=1992 State of Maine Maximum Exposure Guidelines. 4. Bold and shaded text indicates can exceedance of the MCL and/or MEG.5. EPA Region 1 Tier I validation consists of checking for data package completeness and that PE limits are within reporting limits6. 1,4-dioxane is not an included analyte in the trace concentration fraction of the CLP SOM01.2 analysis and, therefore, no result is presented.

12-May-11 11-May-1112-May-11 10-May-11 11-May-11 11-May-11 11-May-11 12-May-1110-May-11 11-May-11 10-May-11 12-May-11 11-May-11 11-May-1111-May-11 12-May-11 11-May-11 12-May-11 10-May-11 9-May-11 9-May-11 10-May-11 11-May-11

1 1 1 1 11/8 1 1 1/4.2 1/2.5 11 1 1 1 1 11 1 1 1 1 1

ESLT-GW-DUP04-0511

ESLT-GW-MW34B2-0511

ESLT-GW-MW23B-0511

ESLT-GW-MW23S-0511

ESLT-GW-MW27B-0511

ESLT-GW-MW30S-0511

ESLT-GW-MW32S-0511

ESLT-GW-MW34B1-0511

ESLT-GW-IS1B-0511

ESLT-GW-IS1S-0511

ESLT-GW-IS2B-0511

ESLT-GW-IS2S-0511

ESLT-GW-MW18S-0511

ESLT-GW-MW20B-0511

ESLT-GW-IN1B1-0511

ESLT-GW-IN1B2-0511

ESLT-GW-IN2B1-0511

ESLT-GW-IN2B2-0511

ESLT-GW-IN3B-0511

ESLT-GW-IN4B-0511

ESLT-GW-DUP01-0511

ESLT-GW-IN6B-0511

ESLT-GW-IN7B-0511

MW-27BIN-4B IN-6B IN-7B IS-1B IS-1S IS-2BIN-1B1 IN-1B2 IN-2B1 IN-2B2 IN-3B IN-4B MW-30S MW-32S MW-34B1 MW-34B1 MW-34B2IS-2S MW-18S MW-20B MW-23B MW-23S

Table 2-5Spring 2011 Groundwater Monitoring Results - VOCsEastern Surplus Company SiteMeddybemps, MainePage 2 of 2


SAMPLE LOCATION

STATION ID


1,1,1-Trichloroethane 0.5 200 200

1,1,2,2-Tetrachloroethane 0.5 NA NA

1,1,2-Trichloro-1,2,2-trifluoroethane 0.5 NA NA


1,1-Dichloroethane 0.5 NA 70

1,1-Dichloroethene 0.5 7 7

1,2,3-Trichlorobenzene 0.5 NA NA

1,2,4-Trichlorobenzene 0.5 70 70

1,2-Dibromo-3-chloropropane 0.5 0.2 0.2

1,2-Dibromoethane 0.5 NA NA

1,2-Dichlorobenzene 0.5 600 NA

1,2-Dichloroethane 0.5 5 5

1,2-Dichloropropane 0.5 5 5

1,3-Dichlorobenzene 0.5 NA 85


1,4-Dioxane NA NA NA

2-Butanone 5 NA 170

2-Hexanone 5 NA NA

4-Methyl-2-Pentanone 5 NA NA

Acetone 5 NA NA

Benzene 0.5 5 5

Bromochloromethane 0.5 NA NA

Bromodichloromethane 0.5 80 NA

Bromoform 0.5 80 NA

Bromomethane 0.5 10 10

Carbon disulfide 0.5 NA NA

Carbon tetrachloride 0.5 5 2.7

Chlorobenzene 0.5 NA NA

Chloroethane 0.5 NA NA

Chloroform 0.5 80 NA

Chloromethane 0.5 NA 3

cis-1,2-Dichloroethene 0.5 70 70

cis-1,3-Dichloropropene 0.5 NA NA

Cyclohexane 0.5 NA NA

Dibromochloromethane 0.5 80 NA

Dichlorodifluoromethane 0.5 NA 1050

Ethylbenzene 0.5 700 700

Isopropylbenzene 0.5 NA NA

m,p-Xylene 0.5 NA NA

Methyl acetate 0.5 NA NA

Methyl tert-butyl ether 0.5 NA 50

Methylcyclohexane 0.5 NA NA

Methylene chloride 0.5 5 48

o-Xylene 0.5 NA NA

Styrene 0.5 100 5

Tetrachloroethene 0.5 5 3

Toluene 0.5 1000 1400

trans-1,2-Dichloroethene 0.5 100 70

trans-1,3-Dichloropropene 0.5 NA NA

Trichloroethene 0.5 5 5

Trichlorofluoromethane 0.5 NA 2300

Vinyl chloride 0.5 2 0.15

DILUTION FACTORSAMPLE DATE

5 U 5 U 5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U







5 U 5 U 5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 5 U 0.5 U 0.39 J 0.5 U 0.5 U








100 U 100 U 100 U R R R 100 U R 100 U R 100 U

10 U 10 U 10 U 5 U 10 U 10 U 5 U 5 U 10 U 10 U 10 U 5 U 10 U 5 U 5 U 5 U 5 U 10 U 5 U 10 U 5 U 24 21 25

10 U 10 U 10 U 5 U 10 U 10 U 5 U 5 U 10 U 10 U 10 U 5 U 10 U 5 U 5 U 5 U 5 U 10 U 5 U 10 U 5 U 5 U 5 U 5 U

10 U 10 U 10 U 5 U 10 U 10 U 5 U 5 U 10 U 10 U 10 U 5 U 10 U 5 U 5 U 5 U 5 U 10 U 5 U 10 U 5 U 5 U 5 U 5 U

12 B 30 B 15 B 5 U 6.5 J 9.9 J 5 U 5 U 7.2 J 9.8 JB 8.6 J 4 J 8 JB 5 U 5 U 5 U 5 U 7.2 J 5 U 330 B 3.6 J 20 19 19 B






5 U 5 U 5 U 0.5 U 5 U 5 U 0.5 U 0.17 J 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U






5 U 5 U 4 J 1.4 5 U 5 U 5.4 3.8 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U


0.88 J 0.54 JB 5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 0.65 J 5 U 0.5 U 0.71 J 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 5 U 0.17 JB 0.2 JB 0.5 U 0.5 U









5 U 2.6 JB 5 U 0.19 JB 5 U 5 U 0.52 B 0.29 JB 5 U 5 U 5 U 0.16 JB 5 U 0.5 U 0.16 JB 0.22 JB 0.17 JB 5 U 0.47 JB 2.5 JB 0.38 JB 0.34 JB 0.27 JB 0.5 U



590 D 5 U 90 23 D 1.2 J 1.2 J 15 0.5 U 10 2.5 J 31 2.8 5 U 2.1 1.4 1.9 3.2 5 U 4.7 1800 D 0.92 0.5 U 0.5 U 0.5 U




5 U 5 U 6.7 2.6 5 U 5 U 6.8 3.6 5 U 5 U 3.5 J 0.5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 5 U 0.5 U 8.7 0.5 U 0.5 U 0.5 U 0.5 U



Notes: 1. All concentrations listed in micrograms per liter (µg/L). 2. "D" = Diluted Result, "J" = Justified Result, "B" = Detected in Lab Blanks, "R"= Results Rejected, CRQL=Contract Required Quantitation Limit.3. MCL=Federal Maximum Contaminant Level, MEG=1992 State of Maine Maximum Exposure Guidelines. 4. Bold and shaded text indicates can exceedance of the MCL and/or MEG.5. EPA Region 1 Tier I validation consists of checking for data package completeness and that PE limits are within reporting limits6. 1,4-dioxane is not an included analyte in the trace concentration fraction of the CLP SOM01.2 analysis and, therefore, no result is presented.

12-May-11 11-May-11 12-May-11 13-May-1111-May-11 11-May-11 10-May-11 10-May-11 10-May-11 10-May-1111-May-11 11-May-11 11-May-11 10-May-11 10-May-11 10-May-1112-May-11 12-May-11 12-May-11 12-May-11

11 1 1 1 1 11 1 1 1 1 11 1 1/2.5 1 1 11/7.1

ESLT-GW-MW49S-0511

ESLT-GW-TB01-0511

ESLT-GW-TB02-0511

ESLT-GW-TB03-0511

ESLT-GW-MW43B1-0511

ESLT-GW-MW43B2-0511

ESLT-GW-MW43S-0511

ESLT-GW-MW44S-0511

ESLT-GW-DUP02-0511

ESLT-GW-MW45S-0511

ESLT-GW-MW3B-0511

ESLT-GW-DUP03-0511

ESLT-GW-MW41B1-0511

ESLT-GW-MW41B2-0511

ESLT-GW-MW42B2-0511

ESLT-GW-MW42SB-0511

ESLT-GW-MW35B-0511

ESLT-GW-MW35B1R-0511

ESLT-GW-MW36B1-0511

ESLT-GW-MW36B2-0511

MW-42SB MW-43B1 MW-43B2 MW-43SMW-35B1R MW-36B1 MW-36B2 MW-3B MW-3B MW-41B1

ESLT-GW-RW1-0511

MW-35B MW-44S Trip Blank 03MW-42B2MW-41B2

11-May-11 11-May-11 12-May-11 10-May-11

1 1 1/20 1

Trip Blank 02Trip Blank 01MW-49SMW-45SMW-44S MW-4B MW-50S MW-51B RW-1

ESLT-GW-MW4B-0511

ESLT-GW-MW50S-0511

ESLT-GW-MW51B-0511

Table 2-6Spring 2011 Groundwater VOC Exceedances Detected by Aquifer Zone



Station Location Station ID Sample Date Aquifer MW-23S ESLT-GW-MW23S-0511 5/10/2011 Northern Plume Overburden 45 D 1.5MW-43S ESLT-GW-MW43S-0511 5/10/2011 Northern Plume Overburden 5 U 5 UMW-44S ESLT-GW-MW44S-0511 5/10/2011 Northern Plume Overburden 1.4 0.5 UMW-44S ESLT-GW-DUP02-0511 5/10/2011 Northern Plume Overburden 2.1 0.5 UMW-45S ESLT-GW-MW45S-0511 5/10/2011 Northern Plume Overburden 1.9 0.5 UIN-1B1 ESLT-GW-IN1B1-0511 5/11/2011 Northern Plume Bedrock 42 5 UIN-1B2 ESLT-GW-IN1B2-0511 5/12/2011 Northern Plume Bedrock 120 5 UIN-2B1 ESLT-GW-IN2B1-0511 5/11/2011 Northern Plume Bedrock 18 0.5 UIN-2B2 ESLT-GW-IN2B2-0511 5/12/2011 Northern Plume Bedrock 45 2.9 JIN-3B ESLT-GW-IN3B-0511 5/10/2011 Northern Plume Bedrock 1.9 0.5 UIN-4B ESLT-GW-IN4B-0511 5/9/2011 Northern Plume Bedrock 0.5 U 0.5 UIN-4B ESLT-GW-DUP01-0511 5/9/2011 Northern Plume Bedrock 0.5 U 0.5 UIN-6B ESLT-GW-IN6B-0511 5/10/2011 Northern Plume Bedrock 2.1 0.53IN-7B ESLT-GW-IN7B-0511 5/11/2011 Northern Plume Bedrock 55 1.4 J

MW-20B ESLT-GW-MW20B-0511 5/11/2011 Northern Plume Bedrock 29 5 UMW-23B ESLT-GW-MW23B-0511 5/12/2011 Northern Plume Bedrock 42 D 3.2MW-27B ESLT-GW-MW27B-0511 5/11/2011 Northern Plume Bedrock 4.6 0.5 UMW-34B1 ESLT-GW-MW34B1-0511 5/12/2011 Northern Plume Bedrock 24 0.5 UMW-34B1 ESLT-GW-DUP04-0511 5/12/2011 Northern Plume Bedrock 24 0.5 UMW-34B2 ESLT-GW-MW34B2-0511 5/11/2011 Northern Plume Bedrock 1.3 J 0.5 UMW-35B ESLT-GW-MW35B-0511 5/12/2011 Northern Plume Bedrock 590 D 0.5 U

MW-35B1R ESLT-GW-MW35B1R-0511 5/12/2011 Northern Plume Bedrock 5 U 0.5 UMW-36B1 ESLT-GW-MW36B1-0511 5/12/2011 Northern Plume Bedrock 90 6.7MW-36B2 ESLT-GW-MW36B2-0511 5/12/2011 Northern Plume Bedrock 23 D 2.6MW-3B ESLT-GW-MW3B-0511 5/11/2011 Northern Plume Bedrock 1.2 J 5 UMW-3B ESLT-GW-DUP03-0511 5/11/2011 Northern Plume Bedrock 1.2 J 5 U

MW-41B1 ESLT-GW-MW41B1-0511 5/11/2011 Northern Plume Bedrock 15 6.8MW-41B2 ESLT-GW-MW41B2-0511 5/10/2011 Northern Plume Bedrock 0.5 U 3.6MW-42B2 ESLT-GW-MW42B2-0511 5/10/2011 Northern Plume Bedrock 10 5 UMW-42SB ESLT-GW-MW42SB-0511 5/10/2011 Northern Plume Bedrock 2.5 J 5 UMW-43B1 ESLT-GW-MW43B1-0511 5/11/2011 Northern Plume Bedrock 31 3.5 JMW-43B2 ESLT-GW-MW43B2-0511 5/11/2011 Northern Plume Bedrock 2.8 0.5 UMW-4B ESLT-GW-MW4B-0511 5/11/2011 Northern Plume Bedrock 5 U 5 U

MW-51B ESLT-GW-MW51B-0511 5/12/2011 Northern Plume Bedrock 1800 D 8.7RW-1 ESLT-GW-RW1-0511 5/10/2011 Northern Plume Bedrock 0.92 0.5 UIS-1S ESLT-GW-IS1S-0510 5/13/2010 Southern Plume Overburden 3.3 0.5 UIS-2S ESLT-GW-IS2S-0510 5/13/2010 Southern Plume Overburden 4.2 0.5 U

MW-18S ESLT-GW-MW18S-0510 5/13/2010 Southern Plume Overburden 1.8 0.5 UMW-30S ESLT-GW-MW30S-0510 5/13/2010 Southern Plume Overburden 1.9 0.5 UMW-32S ESLT-GW-MW32S-0510 5/13/2010 Southern Plume Overburden 0.98 J 5 UMW-49S ESLT-GW-MW49S-0510 5/13/2010 Southern Plume Overburden 3.2 0.5 UMW-50S ESLT-GW-MW50S-0510 5/13/2010 Southern Plume Overburden 4.7 0.5 U

IS-1B ESLT-GW-IS1B-0510 5/13/2010 Southern Plume Bedrock 2.8 0.5 UIS-2B ESLT-GW-IS2B-0510 5/13/2010 Southern Plume Bedrock 4.5 0.5 U

Notes:1. PCE = tetrachloroethene2. All concentrations listed in micrograms per liter (µg/L).3. Bold text indicate concentrations exceeding MEG/IGCL. Italic text indicates concentrations exceeding the MCL.4. CRQL = Contract Required Quantitation Limit, MCL = Federal Maximum Contaminant Limit MEG = 1992 State of Maine Maximum Exposure Guidelines, IGCL = 2000 ROD Interim Groundwater Cleanup Level5. U = below detection limit, D = diluted sample result

CHEMICAL NAME

3

0.5PCE

53

IGCLMEGMCL

CRQLTCE0.5555

Table 2-7Fall 2011 Groundwater Monitoring Results - VOCsEastern Surplus Company SiteMeddybemps, MainePage 1 of 2



1,1,1-Trichloroethane 0.5 200 200 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

1,1,2,2-Tetrachloroethane 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

1,1,2-Trichloro-1,2,2-trifluoroethane 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

1,1,2-Trichloroethane 0.5 5 3 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

1,1-Dichloroethane 0.5 5 5 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

1,1-Dichloroethene 0.5 7 7 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

1,2,3-Trichlorobenzene 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

1,2,4-Trichlorobenzene 0.5 70 70 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

1,2-Dibromo-3-chloropropane 0.5 0.2 0.2 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

1,2-Dibromoethane 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

1,2-Dichlorobenzene 0.5 600 600 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

1,2-Dichloroethane 0.5 5 5 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

1,2-Dichloropropane 0.5 5 5 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

1,3-Dichlorobenzene 0.5 NA 85 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

1,4-Dichlorobenzene 0.5 75 NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

1,4-Dioxane NA NA NA 100 U 100 U 100 U 100 U 100 U 100 U 100 U 100 U 100 U 100 U 100 U 100 U 100 U 100 U 100 U

2-Butanone 5 NA 170 10 U 10 U 5 U 10 U 5 U 5 U 5 U 10 U 10 U 5 U 5 U 10 U 10 U 10 U 10 U 10 U 10 U 5 U 10 U 5 U 5 U 10 U 10 U 10 U

2-Hexanone 5 NA NA 10 U 10 U 5 U 10 U 5 U 5 U 5 U 10 U 10 U 5 U 5 U 10 U 10 U 10 U 10 U 10 U 10 U 5 U 10 U 5 U 5 U 10 U 10 U 10 U

4-Methyl-2-Pentanone 5 NA NA 10 U 10 U 5 U 10 U 5 U 5 U 5 U 10 U 10 U 5 U 5 U 10 U 10 U 10 U 10 U 10 U 10 U 5 U 10 U 5 U 5 U 10 U 10 U 10 U

Acetone 5 NA NA 10 U 10 U 5 U 10 U 5 U 5 U 5 U 10 U 10 U 5 U 5 U 10 U 10 U 10 U 10 U 19 10 U 5 U 10 U 5 U 5 U 10 U 10 U 10 U

Benzene 0.5 5 5 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Bromochloromethane 0.5 80 NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Bromodichloromethane 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Bromoform 0.5 80 NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Bromomethane 0.5 NA 10 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Carbon disulfide 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Carbon tetrachloride 0.5 5 2.7 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Chlorobenzene 0.5 100 NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Chloroethane 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Chloroform 0.5 80 NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Chloromethane 0.5 NA 3 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

cis-1,2-Dichloroethene 0.5 70 70 5 U 5 U 1.2 5 U 0.5 U 0.5 U 0.31 J 5 U 5 U 2.8 0.5 U 5 U 5 U 5 U 5 U 5 U 2.6 J 0.34 J 5 U 0.71 1.9 5 U 5 U 5 U

cis-1,3-Dichloropropene 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Cyclohexane 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Dibromochloromethane 0.5 80 NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Dichlorodifluoromethane 0.5 NA 1050 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Ethylbenzene 0.5 700 700 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Isopropylbenzene 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

m,p-Xylene 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Methyl acetate 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Methyl tert-butyl ether 0.5 NA 50 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Methylcyclohexane 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Methylene chloride 0.5 5 48 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

o-Xylene 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Styrene 0.5 100 5 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Tetrachloroethene 0.5 5 3 6.4 92 13 43 11 0.64 0.3 J 24 22 17 0.38 J 12 13 2.3 J 650 D 5 U 52 6.9 51 6.5 0.5 U 2.3 J 7.6 28

Toluene 0.5 1000 1400 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.41 J 5 U 0.5 U 0.5 U 5 U 5 U 5 U

trans-1,2-Dichloroethene 0.5 100 70 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

trans-1,3-Dichloropropene 0.5 NA NA 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Trichloroethene 0.5 5 5 5 U 5 U 1.2 2.9 J 0.5 U 0.5 U 0.5 U 2.2 J 5 U 1.7 0.5 U 5 U 5 U 5 U 5 U 5 U 3.6 J 0.45 J 5 U 1.8 1.8 5 U 5 U 4.1 J

Trichlorofluoromethane 0.5 NA 2300 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

Vinyl chloride 0.5 2 0.15 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 0.5 U 5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U 5 U 5 U 5 U 0.5 U 5 U 0.5 U 0.5 U 5 U 5 U 5 U

DILUTION FACTOR

SAMPLE DATE

Notes: 1. All concentrations listed in micrograms per liter (µg/L). 2. "D" = Diluted Result, "J" = Justified Result, "B" = Detected in Lab Blanks, CRQL=Contract Required Quantitation Limit.

3. MCL=Federal Maximum Contaminant Level, MEG=1992 State of Maine Maximum Exposure Guidelines. 4. Bold and shaded text indicates can exceedance of the MCL and/or MEG.5. EPA Region 1 Tier I validation consists of checking for data package completeness and that PE limits are within reporting limits6. 1,4-dioxane is not an included analyte in the trace concentration fraction of the CLP SOM01.2 analysis and, therefore, no result is presented.

MW-27B MW-34B2MW-34B1 MW-36B1 MW-42B2 MW-43B1MW-20B MW-35B MW-35B1R MW-36B2IN-1B1 IN-2B2 MW-23B MW-3B MW-41B1 MW-41B2IN-4BIN-3BIN-1B2 IN-2B1 MW-42B2IN-6B IN-7B MW-34B1

ESLT-GW-MW43B1-1111

ESLT-GW-FD01-1111

ESLT-GW-MW42B2-1111

ESLT-GW-MW41B2-1111

ESLT-GW-MW41B1-1111

ESLT-GW-MW3B-1111

ESLT-GW-MW36B2-1111

ESLT-GW-MW36B1-1111

ESLT-GW-MW35B1R-

1111

ESLT-GW-MW35B-1111

ESLT-GW-MW34B2-1111

ESLT-GW-IN7B-1111

ESLT-GW-IN6B-1111

ESLT-GW-IN4B-1111

ESLT-GW-IN3B-1111

ESLT-GW-IN2B2-1111

ESLT-GW-IN1B1-1111

ESLT-GW-FD02-1111

ESLT-GW-MW34B1-1111

ESLT-GW-MW27B-1111

ESLT-GW-MW20B-1111

ESLT-GW-MW23B-1111

8-Nov-11 8-Nov-11 9-Nov-11 9-Nov-118-Nov-11 9-Nov-11 8-Nov-118-Nov-11 8-Nov-11 9-Nov-11 9-Nov-11 9-Nov-1110-Nov-11 10-Nov-11 8-Nov-1110-Nov-11 10-Nov-11 9-Nov-11 10-Nov-11 10-Nov-119-Nov-118-Nov-11 9-Nov-11

1 1/5 11 1 1

8-Nov-11

1 1 1 1 1 11 1 1 1 1 11 11 1 1 1

STATION ID

SAMPLE LOCATION

ESLT-GW-IN2B1-1111

ESLT-GW-IN1B2-1111

Table 2-7Fall 2011 Groundwater Monitoring Results - VOCsEastern Surplus Company SiteMeddybemps, MainePage 2 of 2




1,1,2,2-Tetrachloroethane 0.5 NA NA

1,1,2-Trichloro-1,2,2-trifluoroethane 0.5 NA NA



1,1-Dichloroethene 0.5 7 7

1,2,3-Trichlorobenzene 0.5 NA NA

1,2,4-Trichlorobenzene 0.5 70 70

1,2-Dibromo-3-chloropropane 0.5 0.2 0.2

1,2-Dibromoethane 0.5 NA NA

1,2-Dichlorobenzene 0.5 600 600


1,2-Dichloropropane 0.5 5 5

1,3-Dichlorobenzene 0.5 NA 85


1,4-Dioxane NA NA NA

2-Butanone 5 NA 170

2-Hexanone 5 NA NA

4-Methyl-2-Pentanone 5 NA NA

Acetone 5 NA NA

Benzene 0.5 5 5

Bromochloromethane 0.5 80 NA

Bromodichloromethane 0.5 NA NA

Bromoform 0.5 80 NA

Bromomethane 0.5 NA 10

Carbon disulfide 0.5 NA NA

Carbon tetrachloride 0.5 5 2.7

Chlorobenzene 0.5 100 NA

Chloroethane 0.5 NA NA

Chloroform 0.5 80 NA

Chloromethane 0.5 NA 3

cis-1,2-Dichloroethene 0.5 70 70

cis-1,3-Dichloropropene 0.5 NA NA

Cyclohexane 0.5 NA NA

Dibromochloromethane 0.5 80 NA

Dichlorodifluoromethane 0.5 NA 1050

Ethylbenzene 0.5 700 700

Isopropylbenzene 0.5 NA NA

m,p-Xylene 0.5 NA NA

Methyl acetate 0.5 NA NA

Methyl tert-butyl ether 0.5 NA 50

Methylcyclohexane 0.5 NA NA

Methylene chloride 0.5 5 48

o-Xylene 0.5 NA NA

Styrene 0.5 100 5

Tetrachloroethene 0.5 5 3

Toluene 0.5 1000 1400

trans-1,2-Dichloroethene 0.5 100 70

trans-1,3-Dichloropropene 0.5 NA NA

Trichloroethene 0.5 5 5

Trichlorofluoromethane 0.5 NA 2300

Vinyl chloride 0.5 2 0.15

DILUTION FACTOR

SAMPLE DATE

STATION ID

SAMPLE LOCATION

0.5 U 5 U 5 U 0.5 U 5 U 5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U















100 U 100 U 100 U 100 U 100 U

5 U 10 U 10 U 5 U 10 U 10 U 10 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U



5 U 10 U 10 U 5 U 64 10 U 10 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 5 U 6.3 5.1 6.4


























1.5 22 5 U 0.5 U 1100 D 96 130 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U




0.5 U 5 U 5 U 0.5 U 6.1 5 U 5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U



Notes: 1. All concentrations listed in micrograms per liter (µg/L). 2. "D" = Diluted Result, "J" = Justified Result, "B" = Detected in Lab Blanks, CRQL=Contract Required Quantitation Limit.

3. MCL=Federal Maximum Contaminant Level, MEG=1992 State of Maine Maximum Exposure Guidelines. 4. Bold and shaded text indicates can exceedance of the MCL and/or MEG.5. EPA Region 1 Tier I validation consists of checking for data package completeness and that PE limits are within reporting limits6. 1,4-dioxane is not an included analyte in the trace concentration fraction of the CLP SOM01.2 analysis and, therefore, no result is presented.

MW-51B

ESLT-GW-TB03-1111

ESLT-GW-TB02-1111

ESLT-GW-MW51B-1111

MW-43S MW-4S Trip Blank 02 Trip Blank 03MW-43B2 MW-4B

ESLT-GW-MW4S-1111

ESLT-GW-MW4B-1111

ESLT-GW-MW43S-1111

ESLT-GW-MW43B2-1111

9-Nov-11 10-Nov-11 10-Nov-11 10-Nov-119-Nov-11 9-Nov-11 8-Nov-118-Nov-118-Nov-118-Nov-117-Nov-117-Nov-118-Nov-1110-Nov-1110-Nov-11

1

9-Nov-11

1 11 11 1/8

111111 11111111 11

8-Nov-118-Nov-118-Nov-118-Nov-118-Nov-118-Nov-118-Nov-11

RW-1MW-55BMW-54B Trip Blank 01SW-BK2SW-BK1SW-204SW-203SW-202SW-201SW-201PW-204PW-204PW-203PW-202

ESLT-GW-SW202-1111

ESLT-GW-SW201-1111

ESLT-GW-FD04-1111

ESLT-GW-PW204-1111

PW-201

ESLT-GW-FD03-1111

ESLT-GW-PW203-1111

ESLT-GW-PW202-1111

ESLT-GW-PW201-1111

ESLT-GW-RW1-1111

ESLT-GW-MW55B-1111

ESLT-GW-MW54B-1111

ESLT-GW-TB01-1111

ESLT-GW-SWBK2-1111

ESLT-GW-SWBK1-1111

ESLT-GW-SW204-1111

ESLT-GW-SW203-1111

Table 2-8Fall 2011 Groundwater VOCs Exceedances Detected by Aquifer Zone



Station ID Sample DateESLT-GW-MW43S-1111 11/9/2011 22 5 UESLT-GW-MW4S-1111 11/9/2011 0.5 U 0.5 UESLT-GW-IN1B1-1111 11/8/2011 6.4 5 UESLT-GW-IN1B2-1111 11/8/2011 92 5 UESLT-GW-IN2B1-1111 11/9/2011 13 1.2ESLT-GW-IN2B2-1111 11/10/2011 43 2.9 JESLT-GW-IN3B-1111 11/8/2011 11 0.5 UESLT-GW-IN4B-1111 11/9/2011 0.64 0.5 UESLT-GW-IN6B-1111 11/8/2011 0.3 J 0.5 UESLT-GW-IN7B-1111 11/9/2011 24 2.2 J

ESLT-GW-MW20B-1111 11/10/2011 22 2.5 UESLT-GW-MW23B-1111 11/10/2011 17 1.7ESLT-GW-MW27B-1111 11/8/2011 0.38 J 0.5 U

ESLT-GW-MW34B1-1111 11/8/2011 13 5 UESLT-GW-FD02-1111 11/8/2011 12 5 U

ESLT-GW-MW34B2-1111 11/8/2011 2.3 J 5 UESLT-GW-MW35B-1111 11/10/2011 650 D 5 U

ESLT-GW-MW35B1R-1111 11/8/2011 5 U 5 UESLT-GW-MW36B1-1111 11/9/2011 52 3.6 JESLT-GW-MW36B2-1111 11/9/2011 6.9 0.45 J

ESLT-GW-MW3B-1111 11/9/2011 51 5 UESLT-GW-MW41B1-1111 11/10/2011 6.5 1.8ESLT-GW-MW41B2-1111 11/10/2011 0.5 U 1.8ESLT-GW-MW42B2-1111 11/9/2011 7.6 5 U

ESLT-GW-FD01-1111 11/9/2011 2.3 J 5 UESLT-GW-MW43B1-1111 11/9/2011 28 4.1 JESLT-GW-MW43B2-1111 11/9/2011 1.5 0.5 U

ESLT-GW-MW4B-1111 11/9/2011 5 U 5 UESLT-GW-MW51B-1111 11/10/2011 1100 D 6.1ESLT-GW-MW54B-1111 11/10/2011 96 5 UESLT-GW-MW55B-1111 11/10/2011 130 5 U

ESLT-GW-RW1-1111 11/8/2011 0.5 U 0.5 U

1. PCE = tetrachloroethene2. All concentrations listed in micrograms per liter (µg/L).3. Bold text indicate concentrations exceeding MEG/IGCL. Italic text indicates concentrations exceeding the MCL.4. CRQL = Contract Required Quantitation Limit, MCL = Federal Maximum Contaminant Limit

MEG = 1992 State of Maine Maximum Exposure Guidelines, IGCL = 2000 ROD Interim Groundwater Cleanup Level5. U = below detection limit, J = quantitation approximate, D = diluted sample result

Notes:

Station Location Aquifer IGCL

IN-7B

IN-4B

IN-2B2

IN-1B2

MW-4S

MW-36B2

MW-35B1R

MW-34B2

MW-34B1

MW-23B

MW-3B

MW-41B2

MW-42B2

MW-43B2

RW-1

MW-43B1

MW-42B2

MW-4BMW-51BMW-54BMW-55B

IN-1B1

IN-2B1

IN-3B

IN-6B

MW-41B1

MW-20B

MW-27B

MW-34B1

MW-35B

MW-36B1

Northern Plume Bedrock


Northern Plume BedrockNorthern Plume Bedrock




Northern Plume BedrockNorthern Plume BedrockNorthern Plume BedrockNorthern Plume Bedrock




5

5



3 55



TCEPCE

3


0.5


0.5

Northern Plume OverburdenNorthern Plume Overburden

MEG MCL

CRQLChemical Name

MW-43S

Table 2-9Historical Trends of PCE Concentrations



IN-1B1 IN-1B2 MW-3B MW-34B1 MW-34B2 MW-35B MW-36B1 MW-36B2 MW-43B1 MW-43B2 MW-42S MW-43S MW-45S IS-1B IS-2B MW-50S IS-1S IS-2SNB NB NB NB NB NB NB NB NB NB NO NO NO SB SB SO SO SO

1,400 300 6,600 24 9,100 230 12 150 180 dry dry dry 2 19 42 8 111,800 310 1,100 14 3,200 380 25 220 180 13 51 dry 9 16 42 14 405,700 23 6,100 75 1,200 300 9 110 5 29 11 4 1U 14 5U 6

480 61 10,000 13 850 310 30 40 210 7 19 25 18 13180 81 1,100 11 2,000 350 34 41 48 4 27 4 9 17 16 12 11275 20 2,900 2 590 190 27 37 140 1 7 2 5 8 9 5 7

35 55 610 7 1,700 260 32 44 180 105 4 3 7 10 7 92,100 24 890 12 230 29.5 47 190 2 63 3 4 5 8 9 8

110 150 840 16 120 30 80.5 42 220 950 1.5 1.9 1 7.8 9.5 7.73,600 210 3,000 64 1,650 1 230 20 47 17 110 380 2.5

97 130 1,850 760 1.6 120 6.8 19 5.2 1.7 12 5.7 1.9 0.91 3.9 1.6 2.9110 190 1,700 540 2.4 845 180 18 32 11 1.5 9.6170 200 1,650 36 1.2 535 140 34 28 8.8 6.55 3.3 6.8 7 416 160 490 90 5U 61 10 8.4 1.2 2.715 97 5U 30 5U 22 23 20 2.9 dry 1.5 1.2 0.92 0.5U 4.9 3.9 2.935 195 3.7 510 8.1 220 48 21 28 5.5 1.1 6.5 dry42 120 1.2 24 1.3 590 90 23 31 2.8 dry 5U 1.9 2.8 4.5 4.7 3.3 4.26 92 51 13 2.3 650 52 6.9 28 1.5 dry 23 dry

1. Sample collected in September 20072. Blank = not sampled or a gap in historical data reviewed.3. All concentratio listed in micrograms per liter (µg/L).4. U = below contract required quantitation limit.5. italic text indicates the value listed is the average of the field sample and field duplicate results6. NO = northern overburden aquifer, NB = northern bedrock aquifer, SO = southern overburden aquifer, SB = southern bedrock aquifer

Sample Location

Notes:

April-03April-02

November-01Date

Aquifer

April-06October-05

April-05April-04

October-03

Treatment system and extraction wells offline.Restarted treatment system and extraction wells.

November-11

May-10October-09

May-09October-08

April-08October-07August-07

September-07August-06

October-10May-11

I I I I I I I I I I I I I I I I I I I I

Figure 2-4PCE Concentrations Over Time in Select Northern Bedrock Monitoring Wells



Notes:1. MW-34B2 PCE concentration was below the laboratory detection limit. MW-35B was not sampled in May 2010.2. In the event that a result was below the contract required quantitation limit (CRQL), half of the CRQL was used for plotting purposes.

0

100

200

300

400

500

600

700

800

900

1000

April

-01

April

-02

April

-03

April

-04

April

-05

April

-06

April

-07

April

-08

April

-09

April

-10

April

-11

April

-12

PCE

Con

cent

ratio

ns (u

g/L)

IN-1B1*0.1

MW-34B1*0.1

MW-34B2

IN-1B2*0.1

MW-36B1

MW-36B2

MW-34B1 Exponential Trendline

Treatment System Offline Sept. 06 to Aug. 07

FILL

175.0 / 7.0

BEDROCK

135.3 / 46.7

Steel CasingSet to 14'bgs.

Approximately3" diameteropenborehole intobedrock.

Datum:

Depth to Bottom of Hole (ft.)

BORING LOG

SAMPLE INFORMATION

Advancement

Rig Type / Model: Track / B-53 Mobile

LITHOLOGY

Stabilization TimeTime Depth Below Ground (ft.)

Location: Meddybemps, ME

Boring Location: Center of Northern Well Field,

South of MW-35B

Nobis Rep.: E. Johnson

Size ID (in.)

Boring No.: B-55B

PercentageSoil

StratumElev. / Depth

(ft.)

tracelittle

someand

5 - 1010 - 2020 - 3535 - 50

Ground Surface Elev.: (+/-) 182

Type14 48.55 4 days

Groundwater ObservationsSampler

Core Barrel

2-7/8

Spin/Drive&Wash

Contractor: New Hampshire Boring, Inc.

Driller: C. Knight

Casing

Drilling MethodDate

Date Start: September 7, 2011

Date Finish: September 9, 2011

Dep

th (f

t.)

1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950

of 1

Non-Soilvery few

fewseveral

numerous

Hammer Hoist:

Checked by:

Soil descriptions are based on visual classifications and should be considered approximate. Stratification lines are approximate boundaries between stratums; transitions may be gradual.

SAMPLE DESCRIPTION AND REMARKS(Classification System: Modified ASTM)

Page No. 1

00:0009/13/11 9.94 from TOCDepth of Casing (ft.)

Hammer Type:

4

Nobis Project No.: 80005.00

Project: Eastern Surplus Superfund Site

NOTES:

Depth(ft.)

Rec(in.) N

OTE

S

Gra

phic

Gro

und

Wat

er

Blows/6 in.

Type& No.

BO

RE

HO

LE L

OG

- N

OB

IS G

INT

DA

TA T

EM

PLA

TE O

CT

7 20

11.G

DT

- 1/2

3/12

10:

53 -

R:\8

0000

TA

SK

OR

DE

RS

\800

05 E

AS

TER

N S

UR

PLU

S\F

IELD

INV

ES

TIG

ATI

ON

S\F

ALL

201

1 B

OR

ING

LO

GS

.GP

J WELL DETAIL

,~ - - - - -


r x>;: 4

~ ~

11 11 1.1 -

I~ 11 11 ~ ~

I

FILL

175.0 / 7.0

BEDROCK

135.7 / 46.3

Steel CasingSet to 13'bgs.

Approximately3" diameteropenborehole intobedrock.

Datum:

Depth to Bottom of Hole (ft.)

BORING LOG

SAMPLE INFORMATION

Advancement

Rig Type / Model: Track / B-53 Mobile

LITHOLOGY

Stabilization TimeTime Depth Below Ground (ft.)

Location: Meddybemps, ME

Boring Location: Center of Northern Well Field,

North of MW-35B

Nobis Rep.: E. Johnson

Size ID (in.)

Boring No.: B-54B

PercentageSoil

StratumElev. / Depth

(ft.)

tracelittle

someand

5 - 1010 - 2020 - 3535 - 50

Ground Surface Elev.: (+/-) 182

Type1313

46.344.71

1.25 hrs5 days

Groundwater ObservationsSampler

Core Barrel

2-7/8

Spin/Drive&Wash

Contractor: New Hampshire Boring, Inc.

Driller: C. Knight

Casing

Drilling MethodDate

Date Start: September 7, 2011

Date Finish: September 8, 2011

Dep

th (f

t.)

1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950

of 1

Non-Soilvery few

fewseveral

numerous

Hammer Hoist:

Checked by:

Soil descriptions are based on visual classifications and should be considered approximate. Stratification lines are approximate boundaries between stratums; transitions may be gradual.

SAMPLE DESCRIPTION AND REMARKS(Classification System: Modified ASTM)

Page No. 1

00:0000:00

09/08/1109/13/11

9.07 from TOC9.43 from TOC

Depth of Casing (ft.)

Hammer Type:

4

Nobis Project No.: 80005.00

Project: Eastern Surplus Superfund Site

NOTES:

Depth(ft.)

Rec(in.) N

OTE

S

Gra

phic

Gro

und

Wat

er

Blows/6 in.

Type& No.

BO

RE

HO

LE L

OG

- N

OB

IS G

INT

DA

TA T

EM

PLA

TE O

CT

7 20

11.G

DT

- 1/2

3/12

10:

53 -

R:\8

0000

TA

SK

OR

DE

RS

\800

05 E

AS

TER

N S

UR

PLU

S\F

IELD

INV

ES

TIG

ATI

ON

S\F

ALL

201

1 B

OR

ING

LO

GS

.GP

J WELL DETAIL

,~ - - - - -


r x>;: 4

11 11 11 1·1 -

11 11 11 ~

I

Final Report

Laboratory Anaerobic Microcosm Study with

Groundwater from MW-55B at the

Eastern Surplus Company Superfund Site in Meddybemps ME

to Investigate Anaerobic Dechlorination of PCE and

Removal of Metals during Anaerobic Treatment

And

Review of Literature on Fate of Metals Under Anaerobic Conditions

Nobis Project #80005

January 11, 2011

Prepared for

Nobis Engineering, Inc 18 Chenell Drive, Concord NH 03301

Prepared by

Bioremediation Consulting Inc 39 Clarendon St, Watertown MA 02472

617-923-0976 [email protected]

Bioremediation Consulting Nobis Eastern Surplus Microcosms & Literature Review Final Rpt 1/11/11

2

Final Report Laboratory Anaerobic Microcosm Study with Groundwater from MW-55B at the

Eastern Surplus Company Superfund Site in Meddybemps ME to Investigate Anaerobic Dechlorination of PCE and

Removal of Metals during Anaerobic Treatment and Review of Literature on Fate of Metals Under Anaerobic Conditions

Contents

Summary 3 Sample Receipt and Characterization 4 Microcosm Construction, Amendment, Maintenance and Monitoring 5 Preparation of Microcosm Samples to Determine fate of Four Elements 6 Biodegradation Results 7 Precipitation of Metals in Microcosms Under Anaerobic Conditions 8-9 Literature Review: Fate of Metals Under Anaerobic Conditions 10-12

Recommendations Memorandum 13-15 Table 1 Microcosm data 16 Figure 1 Microcosm Graphs 17 COC for site samples 18 Eastern Analytical Metals Analysis and COC 19

Abbreviations

TCE, trichloroethene DCE, c-dichloroethene VC, chloroethene Ethe, ethene Meth, methane SO4, sulfate Ac, acetate Lac, lactate Pro, propionate Bu, butyrate PO4 phosphate NH4-N ammonia nitrogen NO3, nitrate B12, vitamin B12 ORP oxidation-reduction potential

EOL, emulsified soy oil with lactate


3

Final Report Laboratory Anaerobic Microcosm Study with Groundwater from MW-55B at the

Eastern Surplus Company Superfund Site in Meddybemps ME to Investigate Anaerobic Dechlorination of PCE and

Removal of Metals during Anaerobic Treatment and Review of Literature on Fate of Metals Under Anaerobic Conditions

Summary

Bioremediation Consulting Inc (BCI) was asked by Nobis Engineering, Inc. (Nobis) to assist in the evaluation of the potential for anaerobic in situ bioremediation at the Eastern Surplus Superfund Site in Meddybemps ME. This work included conducting an anaerobic microcosm experiment with groundwater from MW-55B to determine potential for biological dechlorination of PCE to ethene, evaluating the precipitation of four metals during microcosm treatment, conducting a literature review of metal mobility under reducing conditions, and providing a recommendations memo for the pilot test. A final task, preparation of a pilot scale design and implementation memo, will be conducted in conjunction with BCI’s subcontractor XDD (Stratham NH), and will be submitted separately.

Result: The microcosm experiment demonstrated that site groundwater could be made anaerobic by the addition of organic and mineral amendments and inoculating with BCI Dhc dechlorinating culture and that PCE could be dechlorinated completely to ethene within 25 days of inoculation. Under reducing conditions in microcosms, Al, As, and Pb were extensively removed by precipitation, consistent with the findings of the literature review.

Groundwater characteristics. Groundwater and well sediment samples were obtained on 9/29/11 from MW-55B which contained 4.1 mg/L PCE. The absence of daughter products (TCE, DCE, VC, ethene) indicated that no dechlorination was occurring in situ. An unusually high pH of 10.9 probably is a major factor inhibiting microbial activity in this area. The ORP (-54 mV) was not sufficiently low to support reductive dechlorination, and the presence of nitrate-N, rather than ammonia-N, indicates that conditions tend toward aerobic.

Microcosm construction and monitoring. Groundwater (99 ml), and 1 g well sediment were anaerobically transferred to 160 ml serum bottles, leaving 60 cc of anoxic headspace, and sealed with septa through which small samples could be transferred by syringe. Microcosm #1 was made a killed control by lowering pH to 2, while #2 was unamended. Microcosms #3-#5 were amended with lactate and soy oil donor, minerals and vitamin B12 and maintained at neutral pH. After 21 days, #4 and #5 were given BCI dechlorinating culture. Microcosms were monitored for chlorinated compounds and ethene by gas chromatography according to EPA method 5021A, and for sulfate and organic acids by electrophoresis according to EPA method 6500.

Sulfate reduction and Dechlorination. The data demonstrated that native groundwater does not contain sulfate-reducing bacteria capable of reducing sulfate within 21 days, and does not contain dechlorinating bacteria capable of dechlorinating PCE within a 46 day test period. Microcosms inoculated with BCI dechlorinating culture reduced sulfate and dechlorinated 95-98% of the PCE to ethene within 25 days of bioaugmentation.

Fate of Metals. At the end of the test period, microcosm sediment and groundwater were separated and analyzed for metals. In microcosms which supported reductive processes (sulfate


4

reduction and reductive dechlorination), precipitation of metals during the 54 day treatment period was > 99 % for Al, 66 %-100 % for As, 51%-100% for Pb, and 42%-44% for Mn. Sample Receipt and Characterization

Sample receipt. Bedrock samples from MW54B and MW55B were obtained by Nobis 9/8/11. Groundwater and well sediment samples were obtained on 9/29/11, and received on 10/4/11. Sample Appearance.

Groundwater for microcosm tests was sampled into serum bottles containing black FeS reducing agent sufficient to give 0.25 mM FeS. 1-L serum bottle samples appeared black, indicating that the black reducing agent (FeS) was still reduced. The 160 ml serum bottles containing well sediment (obtained pre-purge) appeared gray. The 40 ml vials (without reducing agent) for characterization were clear in appearance. The Rock samples, aerobically packed, consisted mainly of solid rock with a few mg of sand-sized particles.

Groundwater Characterization Methods.

Gas chromatography using EPA headspace method 5021A was conducted by creating 5 cc headspaces in the 40 ml vial samples using a double needle procedure, and standards prepared similarly. 100 µL headspace samples were directly injected into the GC and analyzed as described below for microcosm monitoring. Anions (Cl, SO4, and organic acids) were analyzed according to EPA method 6500. Ammonia and phosphate were analyzed using Hach methods 8155 and 8048, respectively. Field pH and ORP were obtained during sampling by Nobis.

Table A. Groundwater Characteristics mg/L MW meth ethe VC c

DCE TCE PCE Cl SO4 NO3 (1)org

acids PO4 NH4

-N field pH

field ORP

cond. µS

54B .05 .0001 < .002 < .02 < .012 0.6 3.7 5.5 0.4 < 1.5 1.1 < .02 9.1 -24 mV 160 55B .05 .0002 < .002 < .02 < .012 4.1 3.5 6.5 0.4 < 1.5 0.3 < .02 10.9 -54 mV 240

(1) each: acetate, propionate, lactate, butyrate

Evaluation of Characterization data.

The presence of PCE and the absence of daughter products (TCE, DCE, VC, ethene) indicates that no dechlorination is occurring in these well areas. This observation is consistent with the ORP values which are not sufficiently low to support reductive dechlorination. The ionic strength of the groundwater is quite low, suggesting that some minerals needed for microbial growth might be limiting. The presence of nitrate-N, rather than ammonia-N, indicates that conditions tend toward aerobic. The lack of organic acids, which are break-down products of organic materials, indicates a lack of electron donor, causing lack of anaerobic activity.

Selection of well for microcosm testing.

MW-55B, which had a slightly more negative ORP and higher PCE concentration, was selected by Nobis for further testing.


5

Microcosm Construction, Amendment, Maintenance, and Monitoring Site solids transfer to microcosm bottles. The purpose of inoculating each microcosm with solids was to potentially increase the number of dechlorinating bacteria in the microcosm test. Since the rock sample contained only a few grams of small particles, it was decided to use well sediment obtained in the 160 ml well sample. In order to transfer sediment to the microcosm bottles, the sediment was allowed to settle to the bottom of its bottle. Then supernatant groundwater was removed using anaerobic technique, leaving 5 g of sediment slurry. Working in an anaerobic glovebox, 1.0 g of sediment slurry was transferred to each of the five microcosm bottles which had been pre-filled with anoxic gas. The microcosm bottles were then sealed with teflon-coated rubber septa affixed with crimped caps.

Groundwater transfer to microcosm bottles. Using anaerobic technique, 99 ml of MW-55B groundwater was added to each microcosm bottle.

Microcosm Maintenance. Microcosms were maintained in darkness at 21oC and shaken at intervals. (Within the temperature range tolerated by a given organism, its metabolism slows by a factor of roughly two when the temperature is lowered by 10oC.)

Microcosm Plan. #1 Killed Control, prepared by lowering the pH to 2 using 0.5 ml of 6 N HCl. #2 Unamended Control, not amended and did not receive pH adjustment.(initial pH 9.3). #3 Amended with minerals and donor. #4 Amended with minerals and donor, and bioaugmented with BCI Dhc dechlorinating culture. #5 Duplicate of #4

Addition of Amendments. Microcosms # 3 - #5 received anaerobic stock solutions to give: Minerals

10 ppm N and 25 ppm Cl as NH4Cl 15 ppm PO4 and 10 ppm K as KxPO4 10 ppm SO4 and 2.4 ppm Mg as MgSO4 trace elements: ppm: Mn(.084), Co (.13), Zn (.14), Ca (.22), B (.01), Ni (.04), Mo (.02), Cu (.03), W (.03), Se (.02)

Organic Amendments 50 µg/L vitamin B12 36 mg/L Lactate as sodium lactate

30 µL/L (3 µL/bottle) neat emulsified soy oil w 3% Lactate & 1% NaHCO3 from RNAS. on Day 33, microcosms #4 and #5 received 12 mg/L lactate and 10 µL/L soy oil.

pH adjustment.

A pH of 10.9 was measured by Nobis during sampling. However, the pH measured at BCI in a previously-unopened 40 ml vial was 9.8, and the pH in the unamended microcosm measured within an hour of construction had pH of 9.3. According to Nobis, the high pH in this area may be due to Portland cement grout from the well. (A geochemist should be consulted for an explanation of how this could cause the pH to lower slightly during sampling or when exposed to a headspace in a microcosm.) On Day 1, the pH of the amended microcosms was adjusted from 9.3 to 7.6 by adding ~2 mM of HCl. Subsequently, to maintain pH near neutral, additional 2.8 mM HCl was added to #3, 2 mM to #4 and 1.3 mM #5.


6

Bioaugmentation. Microcosm #4 and #5 were bioaugmented on Day 21 with 0.4 ml of BCI Dehalococcoides (Dhc) Culture capable of dechlorinating PCE completely to ethene. The purpose of waiting until Day 21 was to determine whether the site groundwater contained native sulfate-reducing bacteria or native dechlorinating bacteria. Analytical Methods for Microcosm Monitoring

Methane, ethene, and chlorinated compounds were monitored by removing 100 µL samples of microcosm headspace and injecting into a HP 5890 gas chromatograph according to EPA Method 5021A. Standards were prepared similarly, and analyzed in the same manner as samples. ChemStation software was used to calculate response factors and quantitate sample results. Concentrations reported are those that would be present if each compound were completely in the aqueous phase (not partially in the headspace).

Dissolved molecular H2 was monitored by removing 100 µL headspace samples, diluting with ultra-pure Argon, and injecting into a Trace Analytical Instrument. The instrument was calibrated using a H2 standard (Messer Industries). Concentrations reported are those that were actually in the aqueous phase (approximately 1/50 of the headspace concentration).

Nitrate, sulfate and organic acids were determined by removing 200 µL aqueous samples and analyzing according to EPA Method 6500. Samples were diluted 10-fold for analysis. Compounds were identified by retention time ratio in comparison with standards analyzed with each batch. Response factors were calculated and results quantified by Waters Empower software. pH was determined by removing 300 µL aqueous samples and measured with a ThermoOrion model 290A pH meter and a Sure-flow Ross semi-micro electrode. Preparation of Final Microcosm Samples to Determine Fate of Four Elements

It was of interest to determine whether the reductive processes in the microcosms had resulted in the precipitation of four metals (As, Al, Pb, Mn). For this study, sediment and groundwater samples were obtained for two control microcosms (#2 and #3) in which no reductive processes had been observed, and from the two bioaugmented microcosms (#4 and #5) in which sulfate reduction had occurred and dechlorination had been extensive, proceeding to 95%- 98% ethene.

Samples of sediment and groundwater were obtained from these four bottles on day 54 by placing the microcosm bottles in a vertical position and allowing the solids to settle for 4 hr until each bottle had a clear supernatant liquid and a precipitate. At this point, the supernatant liquid was anaerobically transferred by syringe to a second serum bottle, creating a separate precipitate and supernatant sample for each original microcosm, making a total of eight samples. These were shipped to Eastern Analytical for analysis of the four metals by Method 200.8.


7

Biodegradation Results Table 1 presents data for all five microcosms, including gas chromatograph data for chlorinated compounds and methane and ethene and H2, electrophoresis data for sulfate and organic acids, and pH adjustment data. Figure 1 presents graphs of microcosms #1 to #4, showing sulfate reduction and concentrations of PCE, cDCE, VC and ethene. #1, Killed Control.

• No dechlorination of PCE was observed during the 46 day test period. Importantly, no detectable TCE, DCE, or VC was observed.

#2, Unamended Control at pH 9.3

• No sulfate reduction, and no PCE dechlorination to TCE, was observed during the 49 day test, indicating that there is no native donor and/or there are no native sulfate-reducing bacteria or dechlorinating bacteria which function at pH 9.3.

• The observed lack of organic acid and H2 production during the microcosm test is consistent with the lack of sulfate reduction and dechlorination.

#3, Amended Microcosm (minerals, donor, B12) at pH 7.3

• No sulfate reduction was observed during the 49 day test, and no PCE dechlorination to TCE was observed.

• The lack of reductive processes in this microcosm which had ‘optimal’ conditions (two donor types, neutral pH, minerals and vitamin B12) indicates that there are no native sulfate-reducing bacteria and no native dechlorinating bacteria.

• Native bacteria able to utilize lactate to generate acetate and H2 at pH 7 are present.

#4, Amended Microcosm (minerals, donor, B12) at pH 7.3, Bioaugmented with BCI Dhc Culture

• BCI dechlorinating culture contains Dhc dechlorinating bacteria, as well as organic acid utilizing bacteria which produce H2, sulfate-reducing bacteria, and methanogens.

• In this microcosm, sulfate reduction was 80% complete by Day 32, and 100 % complete by Day 46. During sulfate reduction, lactate was utilized and acetate accumulated.

• Dechlorination of PCE to cDCE was complete by Day 32. • Dechlorination of cDCE by Dhc to ethene was 98 % complete by Day 46. During

dechlorination, lactate utilization and acetate generation continued. Molecular H2 was low, indicating uptake by dechlorinating organisms.

• After dechlorination, methane was generated by methanogenic organisms.

#5, Duplicate Amended Microcosm, Bioaugmented • Results were similar to those for #4. PCE was 95% dechlorinated to ethene in 49 days.

Summary of Sulfate Reduction and Dechlorination.

Native groundwater contains neither sulfate-reducing bacteria nor bacteria capable of dechlorinating PCE able to function within a 46 day test period when given neutral pH, mineral amendment and vitamin B12. BCI dechlorinating culture dechlorinated 95-98% PCE to ethene in an amended microcosm within 25 days of bioaugmentation.


8

Precipitation of Metals in Microcosms Under Anaerobic Conditions

Tables 2a - 2d During sampling, FeS was added to the groundwater. Microcosms were amended as described above. Supernatant and precipitate in four microcosm bottles (#2 - #5) were separated on Day 54 at BCI as described under Methods and submitted to Eastern Analytical (EA) for analysis of four elements. At EA the precipitate was extracted with 50 ml of acid prior to analysis. In order to report metals concentrations for the precipitate in mg/L, the EA precipitate data was divided by 20. The EA report is attached. In Table 2, Reducing Conditions indicates microcosms which exhibited both sulfate reduction and dechlorination.

Table 2-a Aluminum bottle

pH SO4 reduction

and dechlorination

Supernatant on day 56

mg/L

Precipitated from original GW

mg/L

Calculate Total mg/L

Removed by Treatment

% #2 9.3 No 0.70 13 13.7 95 #3 7 No < 0.05 10.5 10.5 100 #4 7 yes < 0.05 12 12.0 100 #5 7 yes 0.05 10 10.05 99.5

Table 2-b. Arsenic

bottle

pH SO4 reduction and

dechlorination


mg/L


mg/L


Removed by treatment

% #2 9.3 No .003 0.0014 0.0044 32 #3 7 No .004 0.0014 0.0054 26 #4 7 yes < 0.001 0.0019 < 0.0029 66 - 100 #5 7 yes < 0.001 0.0016 < 0.0026 62 - 100

Table 2-c. Lead

bottle


dechlorination


mg/L


mg/L



% #2 9.3 No < 0.001 0.00120 < .00220 55 - 100 #3 7 No < 0.001 0.00105 < .00205 51 - 100 #4 7 yes < 0.001 0.00125 < .00225 56 - 100 #5 7 yes < 0.001 0.00105 < .00205 51 - 100

Table 2-d. Manganese

bottle


dechlorination


mg/L


mg/L



% #2 9.3 No < 0.005 0.16 0.16 100 #3 7 No .21 0.11 0.32 34 #4 7 yes .18 0.14 0.32 44 #5 7 yes .15 0.11 0.26 42

(1) The mineral amendment added 0.08 mg Mn / L to the amended microcosms. Mn may also have been present in donor.

I


9

Discussion of Metals Precipitation Results (Tables 2-a to 2-d)

Aluminum: The results in Table 2-a show that > 99 % of the aluminum was removed from the supernatant groundwater in the amended (#3) and amended-bioaugmented microcosms (#4 & #5). The unamended microcosm experienced only 95% removal of Al, possibly the result of its higher pH 9.3.

Arsenic: Arsenic, initially present at about 0.005 mg/L, was only 32% to 36% removed by precipitation in the microcosms that did not show reductive processes (#2 &#3). In the microcosms that supported sulfate reduction and dechlorination, arsenic was removed to non-detectable levels (<0.001 mg/L), indicating that removal was between 64% and 100%. These results support the findings of others that arsenic binds to sulfidic precipitates.

Lead: Lead was present in the precipitate of all microcosms, and had been reduced to non-detectable concentrations in supernatant groundwater, indicating that the original concentration had been .00115 ± .00010 mg/L, and that the removal had been between 50% and 100%. It is likely that the lead precipitated as PbS as a result of the 0.25 mM FeS added to the original groundwater sample.

Manganese: In the unamended microcosm (#2) the original groundwater apparently contained 0.16 ppm manganese, which was removed to a non-detectable concentration by precipitation during the test. The calculated total manganese in the amended microcosms was higher (0.26 to 0.32 mg/L), because the mineral amendment contributed 0.08 mg Mg/L. The Mn precipitated in the amended microcosms was 34% to 44%, significantly less than that in the unamended microcosm. This result may indicate that Mn precipitation is greater at pH 9.3 than at pH 7.

Summary. In microcosms which supported the reductive processes of sulfate reduction and reductive dechlorination of PCE precipitation of metals during the 54 day treatment period was >99% for Al, 66% to 100 % for As, 51-100% for Pb, and 42-44% for Mn. Discussion. According to the literature review (conducted by BCI, attached below), if the remediation promotes fixation through precipitation or by adsorption, the insoluble complexes will tend to be “long-lasting”. The literature did not specifically mention re-dissolution of sulfides when conditions change back to aerobic, however the implications are that they will not re-dissolve during a remedial time frame. In order to validate this assumption for this site, groundwater samples should be monitored for metals during remediation.


10

Literature Review: Fate of Metals Under Anaerobic Conditions

Summary. Information on the mobilization and properties of four metals, lead (Pb), manganese (Mn), aluminum (Al) and arsenic (As) under anaerobic conditions was reviewed. The literature indicated that three metals of concern, Pb, Mn and As, are likely to be removed from solution by precipitation or binding under reducing conditions. However, the literature reviewed did not specifically address the removal of metals under the stronger reducing conditions required for reductive dechlorination. Limited information on the fate of aluminum suggested that its solubility may increase under anaerobic conditions. Due to the complexity of metals interaction with the subsurface environment, and the additional factors introduced during active anaerobic remediation, it is advisable to monitor metal concentrations during pilot testing.

Introduction.

The literature review focused on the environmental properties and fate of four metals under reducing conditions in groundwater, to address the concern raised by the Eastern Surplus Site stakeholders regarding potential mobilization of metals as a result of treatment of groundwater by reductive dechlorination of PCE. This anaerobic treatment process often includes pH adjustment, addition of electron donors such as sodium lactate or vegetable oil, small amounts of ammonium and phosphate, and addition of dechlorinating bacteria able to transform PCE to ethene. These materials induce changes in the subsurface, including conversion of aerobic to anaerobic conditions. A change in the oxidation-reduction potential (ORP) from + 100 mV to -200 mV is to be expected at the Eastern Surplus Site if reductive dechlorination is undertaken, and is expected to affect the properties of naturally occurring metals.

Factors that control metal availability and mobility are solubility, adsorption, entrapment in crystal lattices, and precipitation (Hamon et al. 2002). Such changes could increase the water solubility of some metals making them available for discharge to surface water bodies located 100 feet down gradient of the plume area. Alternatively, some metals will form insoluble sulfides or bind to biomass and surfaces and become less mobile. If the remediation promotes fixation through precipitation or by adsorption, the insoluble complexes will tend to be long-lasting.

Site Background. The data for metals discussed in this report was obtained in 2011 by analysis of groundwater collected from 31 wells at the Eastern Surplus Site, and was provided by Nobis Engineering. The four metals found to exceed the State of Maine’s Maximum Exposure Guidelines (MEG) are aluminum, arsenic, manganese, and lead. Of these, lead showed a 2-fold exceedance, whereas the others showed 10-fold or greater exceedances (Table 1).

Table 1. Occurrence and Extent of Exceedance of the ME MEG for four metals in 31 Wells at the Eastern Surplus Site sampled in 2011

Metals Exceeding ME MEG

ME MEG µg/L

Number of Wells Exceeding MEG

Range of Exceedance µg/L

Aluminum (Al) 200 4 2,000 to 4,000 Arsenic (As) 1 5 15 to 31 Manganese (Mn) 15 2 272 to 867 Lead (Pb) 10 1 23


11

Factors Affecting Metal Mobility of Iron, Lead, Aluminum and Manganese

Mobilization of metals from soil and sediment is strongly controlled by the aerobic conditions in that these metals exist as insoluble hydroxy oxides under aerobic conditions and have strong adsorptive properties which favor attenuation. As a result of development of anaerobic conditions these metal oxides are converted to metallic ions or insoluble sulfides (Fuller, 1977). A factor that affects the solubilization of these metals is the extent of reducing conditions as expressed by the ORP, e.g. 0 mV for iron-reduction, -180 mV for sulfate-reduction and dechlorination, and -250 mV for methane generation.

Other factors that affect solubilization are pH, metal concentration, and concentration of soil organic matter. Organic matter from electron donor amendments such as emulsified vegetable oil affects metal mobility, particularly due to the resulting biomass and soil organic matter which will reduce metal mobility due to the formation of insoluble reaction products.

Other mechanisms of attenuation include precipitation and entrapment into crystal lattices. There may be a transition period when the aquifer is being converted from oxidizing to reducing, when metal hydroxy oxides will dissolve, mobilizing these metals. Aluminum appears to be an exception, since under anaerobic conditions it forms unstable sulfides, keeping aluminum in solution (Holleman and Wiberg, 2001). Low concentrations of ions or salts experience more complete attenuation than high concentrations due to availability of binding sites on other precipitates and rock surfaces.

Formation of low-solubility sulfides under anaerobic conditions is usually associated with the generation of sulfides by microbial sulfate reduction. Published data from numerous sources (CRC Press and others) suggest that these metal sulfides have very low water solubilities as shown in Table 2.

Table 2: Solubility Product Constants, (Ksp) for selected Sulfides Iron (II) Sulfide 6 x 10-17 Lead (II) Sulfide 3 x 10-7

Manganese Sulfide* 3 x 10+7, 1 x 10-11, 1 x 10-15 Aluminum Sulfide Unstable, reacts with water to form oxides *Conflicting data were found for Mn.

Factors Affecting Mobility of Arsenic

Arsenic in rock exists as a semi-metallic element (As0) but upon mobilization exists in water primarily in the arsenite (As3+) and arsenate (As5+) forms.

Arsenate forms a triprotic weak oxoacid acid (arsenic acid, H3AsO4) which has a low pKa1 of 2.19 and a pKa2 of 6.94, so that it exists in most waters as either a monovalent or divalent anion. Therefore, in soils and sediments it can be bound by positively charged elements like aluminum and iron, clays, and ferric iron oxides/hydroxides. Arsenite also forms a triprotic weak oxoacid acid (arsenous acid, H3AsO3) with a pKa1 of 9.20. As a result, ionic immobilization by nonspecific sorption to cationic species is much less relevant to arsenous acid in normal waters, soils, or sediments.


12

A complicating factor for anaerobic in situ bioremediation is that ferric iron, which is insoluble and forms iron hydroxides (a useful anion exchange sink which sorbs mono and divalent arsenate oxyanion species), will be reduced to soluble ferrous iron under strong reducing conditions (Fuller, 1977). The latter condition results when electron donor is added to reduce the ORP of groundwater in order to achieve conditions suitable for reductive dechlorination. Destruction of the ferric iron “sink” for arsenate may release the previously bound arsenate into groundwater. Additionally, under reducing conditions some of the arsenate will be reduced to arsenite. The latter exists as a neutral species at pH < 9. Arsenite will have a reduced tendency to sorb to cations in the soil or sediment, resulting in release into the groundwater.

Role of sulfate reducing bacteria (SRB) in formation of sulfides and precipitation of arsenate and arsenites. Kirk (2004) demonstrated reduced levels of arsenic in an anaerobic aquifer which was attributed to bacterial sulfate reduction. Where SRB are active, the sulfide produced reacts to precipitate arsenic. Pure strains of sulfate-reducing bacteria which cause arsenic to precipitate as arsenic trisulfide have been studied (Newman et al., 1997).

Conclusions The literature on mobilization of the metals Pb, Mn, Al and As under anaerobic conditions suggests that the solubility of aluminum may increase, resulting in increased mobilization. Pb, Mn and As will likely experience reduced solubilities under reducing conditions. References:

Deniji, A., 2004. Bioremediation of Arsenic, Chromium, Lead and Mercury. National Network of Environmental Management Studies, U.S. EPA, Technology Innovation Office, Washington DC. www.clu-in.org.

Fuller, S.H., 1977. EPA-600/2-77-020, April 1977. Movement of Selected Metals, Asbestos, and Cyanide in Soil: Applications to Waste Disposal Problems.

Hamon, R., M. McLaughin and G. Cozens. 2002. Mechanisms of Attenuation of Metal Availability in In Situ Remediation Treatments. Environ. Sci. Technol. 36: 3991-3996.

Handbook of Chemistry and Physics, 92nd Edition, 2011-2012. Taylor and Francis Group, Boca Raton, FL.

Holleman, A.F. and E. Wiberg. 2001. Aluminum Sulfide Soluibility in Inorganic Chemistry. Academic Press, San Diego. ISBNO-12352651-5.

Lehr, I., J.W. Keeley, Lehr, J.K., Kingery, T.B., 2010. Wiley InterScience, Water Encyclopedia.

Kirk, M.F., Holm, T.R., Park, J., Jin, Q.S., Sanford, R.A., Fouke, B.W., and Bethke, C.M., 2004, Bacterial sulfate reduction limits natural arsenic contamination in groundwater: Geology, v. 32, p. 953-956.

Newman, D.K., Beveridge, T.J., and Morel, F.M.M., 1997, Precipitation of arsenic trisulfide by Desulfotomaculum auripigmentum: Appl. and Environ. Microbiol., v. 63, p. 2022-2028.

Zobrist, J. 2000. Mobilization of Arsenite by Dissimilaory Reduction of Adsorbed Arsenate. Environ.Sci.Techlol. 34:4747-4753.


13

Recommendations Memorandum, Pilot Test Conceptual Design, Amendment Plan, and Monitoring Plan

Goals of Pilot Test Design. The preparation of a pilot scale design and implementation memo will be conducted in conjunction with BCI’s subcontractor XDD (Stratham NH), and will be submitted separately. The purpose of the pilot test is to confirm the level of effort that will be necessary to mobilize, construct a groundwater recirculation system, distribute amendments, maintain pH, confirm the survival and functioning of the dechlorinating bacteria, and complete the dechlorination to ethene. BCI will provide a conceptual design that will address controlled recirculation of groundwater, amendment with mineral nutrients and donor, injection of dechlorinating culture, and collection of monitoring samples.

Need for Bioaugmentation. BCI’s microcosm test with MW55B groundwater/sediment indicated that the site does not contain dechlorinating bacteria, but that BCI’s culture of dechlorinating bacteria can thrive in site water which has been amended with minerals, electron donor, and has been brought to a neutral pH. BCI should be directed to expand the volume of Microcosm #4, which is BCI’s dechlorinating culture acclimated to amended, neutralized site groundwater. This bioaugmentation culture would be ready for injection when the site groundwater has been neutralized and amended and the remedial system has been tested.

Location of the Pilot Area at the Test Site. BCI will work with XDD and Nobis to delineate the pilot treatment area and define a recirculation strategy. The site already has monitoring wells which can be incorporated into the pilot area. Also, the pilot treatment area should be located and aligned so that wells installed for the pilot test will be positioned for future incorporation into further full scale remediation, if conducted. BCI will work with XDD and Nobis to review the information on groundwater flow, pH and location of existing wells, to evaluate potential locations for the pilot test.

Design for Groundwater Recirculation. The pilot test area should include one or more extraction wells to remove groundwater from the test area, and one or more injection wells, pumps and above-ground piping to transport the extracted groundwater to the injection wells, and one or two monitoring wells located midway between the extraction and injection wells. The entire system should be airtight to keep O2 out of the water. The design should include an anaerobic amendment tank, from which donor, minerals and pH buffer can be metered into the recirculating groundwater.

Advantage of Recirculation. By creating a cone of depression at the extraction well, and a mound of groundwater at the injection well, the percentage of groundwater “captured” in the recirculation system can be increased, allowing inoculated Dhc, amendments and dechlorination daughter products to be retained in the test system. This approach has been used by others (Major et al., 2002) (Ellis et al., 2000). A simplified diagram of groundwater recirculation with amendment tank is presented in Figure 1.

Estimating Donor Requirement. Excess soy oil (C18) donor should be avoided because it will be degraded to organic acids which lower the pH. The minimum donor requirement for a closed system can be calculated from the concentrations of contaminants and competing electron acceptors based on 8 electrons needed per mol for both PCE and SO4, and dividing by 30 electrons provided per mol of C18, and multiplying by the molecular weight of C18 (280 g/mol). However, the actual amount of PCE in the treatment cell may be greater than the amount in


14

groundwater because a significant amount of PCE may be adsorbed to the sediment and rock formation. Furthermore, the treatment cell for the pilot test is not a closed system, in that some groundwater enters from upgradient, and some exits downgradient, and donor is lost from the treatment area. Also, some donor is consumed by microbes for growth. If donor (organic acids) are monitored and if donor amendments are not excessive, organics that escape from the treatment area will be readily degraded by native bacteria down gradient.

Maintaining Optimal Donor. Since it is not practical to try to predict the exact donor demand of in situ treatment, donor use should be monitored by sampling the groundwater at intervals, shipping the samples to BCI, for fast-turn-around analysis for donor breakdown products, organic acids, which break down slowly to maintain a supply of H2 for the dechlorinating bacteria. Groundwater samples should be analyzed for these organic acids at BCI. Additional donor should be injected into the groundwater to maintain total organic acids at about 50 mg/L.

Mineral Amendment. In order to conduct an in situ treatment in a reasonable time, the microbes performing the dechlorination, sulfate-reduction, and production of H2 from donor must be able to increase in numbers. Microbial biomass weight consists of 50% carbon, 15% nitrogen, 3.2% phosphorus, and lesser amounts of 14 ‘minor’ and ‘trace’ elements. Nitrogen and phosphate are the most likely to become limiting during a remediation. Although the other elements are usually present in sufficient quantities in the groundwater or soil, an elemental analysis should be conducted on the groundwater assure that these are present. Nitrogen should be added in its reduced form, ammonia (NH4

+). PO4 could be added as tri-poly-phosphate because this form has less tendency to precipitate.

Maintaining Adequate NH4 and PO4 Amendment Amounts. Because PO4 binds strongly to certain soils, it is not possible to readily assess the total reservoir of phosphate in the treatment area. Ammonia also binds to soil. Bacteria require only that “some” N and PO4 be dissolved in the groundwater. During the pilot test, groundwater samples from monitoring wells should be analyzed for NH4 and PO4 by Hach methods. Initially these minerals will be added to give 100-200 mg/L each. When the concentrations fall below 5 mg/L, additional mineral amendment mix should be added to the amendment tank.

Preparing Groundwater pH for Culture Injection. Prior to injection of the Dhc dechlorinating culture, it will be necessary to stabilize the pH to near-neutral values. Since pH in wells appears to vary from 5.9 to 12, it may be possible to moderate the pH in the pilot area by recirculating and mixing the groundwater prior to adding other amendments. BCI will discuss a strategy for further moderating pH and for maintaining pH by metering in buffer or acidic amendment via the amendment tank.

Preparing Groundwater ORP for Culture Injection. Prior to injecting Dhc culture, it is necessary to create strong reducing conditions in the groundwater (-180 mV). Since most wells at this site have positive ORP, after mixing the groundwater in the test area, the ORP will likely be positive. Lowering the ORP can be accomplished biologically using the process of sulfate reduction. For this, we would need to add sulfate, donor and minerals, and a BCI culture containing sulfate-reducing bacteria. Lowering the ORP by adding Na2S or zero-valent iron can also be considered. During the ORP reduction step, samples should be monitored for sulfate concentration.

Monitoring and Adjusting pH. During the pilot test, pH should be monitored and adjusted as needed by metering small amounts of sodium hydroxide or HCl into the amendment tank.


15

Monitoring Chlorinated Ethenes. Samples from monitoring wells will be shipped to BCI for fast-turn-around analysis of dissolved chlorinated contaminants (PCE, TCE), and their daughter products (DCE, VC, and ethene) by EPA headspace Method 5021A. BCI’s analysis has been accepted by EPA for monthly process monitoring of chlorinated compounds at pilot and full scale anaerobic remediation such as the Malvern Superfund Site (Voci, C., et al, 2008).

Survival of Dechlorinating Culture During Injection. The dechlorinating culture should not be exposed to abrupt changes in the salt concentration during bioaugmentation. Therefore BCI grows our culture in site groundwater, and will supply an appropriate container for shipping groundwater to BCI. BCI will supply injection instructions to ensure that the dechlorinating bacteria are not exposed to oxygen during the injection process.

Quality Assurance Project Plan. BCI will work with XDD to develop a Quality Assurance Project Plan that addresses guidelines for record-keeping, and a program of analytical quality control. References

Ellis, D. E., E. J. Lutz, J. M. Odom, R. J. Buchanan, Jr., C. L. Bartlett, M. D. Lee, M. R. Harkness, and K. A. DeWeerd. 2000. Bioaugmentation for Accelerated In Situ Anaerobic Bioremediation. Environmental Science and Technology. 34(11):2254-2260.

Major, D, M. L. McMaster, and E. E. Cox. 2002. Field Demonstration of Successful Bioaugmentation to Achieve Dechlorination of Tetrachloroethen to Ethene. Environ. Sci. Technol. 36(23):5106-5116.

Voci, C. J., M. S. Kozar, M. Findlay, and S. Fogel. 2008. Bioaugmentation Overcomes Inhibitory Conditions Resulting in Complete TCA and TCE Dechlorination in Fractured Rock. Sixth International Conference on Remediation of Chlorinated and Recalcitrant Compounds, May 20-24, Monterey, CA.

Figure 1. Simplified groundwater recirculation conceptual design

Pilot Layout for Groundwater Recirculation

amendment .------''------1 tank

inject

~ flow

monitor

- ---------- 20 ft

above-ground piping

Unsaturated soil

withdraw


16

engineering a sustainable future draft bioremediation bench ...nh-3423-2012-d nobis engineering,...

Documents