KGS_2018f_Summary_of_Changes_to_the_LTMMP_for_Area_of_Contamination_A7_Sudbury_Devens.pdf

KOMAN Government Solutions, LLC Phone (508) 366-7442 293 Boston Post Road West, Suite 100 Fax (508) 366-7445 Marlborough, Massachusetts 01752 www.komangs.com

October 27, 2018

U.S. Army Corps of Engineers New England District 696 Virginia Road Concord, MA 01742-2571 Attn: Ms. Penelope Reddy

RE: Summary of Changes to the LTMMP for Area of Contamination A7 Former Sudbury Training Annex, Sudbury, MA Contract No. W912WJ-18-C-0011

Dear Ms. Reddy, KOMAN Government Solutions, LLC (KGS) is pleased to provide the enclosed update to the 2015 Long- Term Monitoring and Maintenance Plan (LTMMP) for Former Fort Devens Army Installation and Sudbury Annex (Sovereign Consulting, Inc., February 2015). The enclosed summary table pertains to Area of Concern (AOC) A7 at the former Sudbury Training Annex and is intended to formally document the changes that were implemented during 2017 in accordance with the approved recommendations in the 2016 Five-Year Review Report for the Former Sudbury Training Annex (KGS, September 2016) and the 2016 Annual Report (KGS, July 2017). These changes will be carried forward during the fall 2018 and subsequent monitoring events.

Please contact me at (508) 219-6771 or jropp@komangs.com if you have any questions or require additional information.

Sincerely, KOMAN Government Solutions, LLC

James Ropp, P.E.

Project Manager cc: Robert Simeone, BRAC Devens, MA Ken Heim, USACE Katherine Malinowski, USACE Christine Williams, EPA Region 1, Boston, MA David Chaffin, MassDEP Boston Tom Eagle, USFWS, Sudbury, MA

KGS File

Summary of Changes to the LTM Program for AOC A7 at the Former Sudbury Training Annex

Well OHM-A7-08 VOCs, Pesticides, Total Metals, COD, Cyanide

VOCs2, Pesticides, COD, Cyanide

Annual Biennial in Fall4 Removal of total metals analysis; VOCs analyses to include only COPCs; reduced sampling frequency from annual to biennial based on maintained downward trend in concentrations.

Well SUD-A07-014 VOCs, Pesticides, Total Metals, COD, Cyanide

VOCs2, Pesticides, COD, Cyanide

Annual Biennial in Fall4 Removal of total metals analysis; VOCs analyses to include only COPCs; reduced sampling frequency from annual to biennial based on no groundwater analytical exceedance at upgradient well.

Well SUD-A07-065 VOCs, Pesticides, Total Metals, COD, Cyanide

VOCs2, Pesticides, COD, Cyanide

Annual Biennial in Fall4 Removal of total metals analysis; VOCs analyses to include only COPCs; reduced sampling frequency from annual to biennial based on maintained downward trend in concentrations.

Well Point SUDWP-A07-01 VOCs, Pesticides, Total Metals, COD, Cyanide

VOCs2, Pesticides, COD, Cyanide

Annual

Annual in Fall (or in the spring if the well is dry in the fall, as per Section 6.7 of the 2016 Five Year

Review)3

Removal of total metals analysis; VOCs analyses to include only COPCs.

Gas Vent A7-1 through A7-4 Methane, carbon dioxide, oxygen, LEL, total VOCs

No change Annual Every 5 years

Reduced sampling frequency to once every 5 years before the 5-Year Review in accordance with recommendation in the 2015 LTMMP (Sections 2.1.8.2, 3.6), 2106 Annual Report (Section 7.0), and 2017 Annual Report (Section 5.0). The next gas monitoring event will be in Fall 2020 in preparation for the 2021 5-Year Review.

QC A7-Trip Blank VOCs -- -- --5 No changes

QC A7-Duplicate VOCs, Pesticides, Total Metals, COD, Cyanide

VOCs2, Pesticides, COD, Cyanide

Annual Annual5

Change in analytes as noted above. During biennial sampling events (2018, 2020, etc.), the duplicate sample will be collected from OHM-A7-

08. During the alternate annual sampling events (2019, 2021, etc.), the duplicate sample will be collected from SUDWP-A07-01.

Sample Type

Well ID

LTMMP Change Comparison Groundwater Wells

QC Samples

LTMMP

Sample Analysis

Current LTMMP Sample

Analysis

2015 LTMMP

Sample

Frequency

Current LTMMP Sample

Frequency6 Summary of LTMMP changes(1)

Gas Vents

KGS Page 1 of 2 October 2018

Summary of Changes to the LTM Program for AOC A7 at the Former Sudbury Training Annex

QC A7-Matrix Spike VOCs, Pesticides, Total Metals, COD, Cyanide

VOCs2, Pesticides, COD, Cyanide

Annual Annual5

Change in analytes as noted above. During biennial sampling events (2018, 2020, etc.), the MS sample will be collected from well SUD-A07-

065. During the alternate annual sampling events (2019, 2021, etc.), the MS sample will be collected from SUDWP-A07-01. The lab will be notified of the historical contaminant concentrations in these wells so that the MS can be prepared at an appropriate level.

QC

A7-Matrix Spike

Duplicate

VOCs, Pesticides, Total Metals, COD, Cyanide

VOCs2, Pesticides, COD, Cyanide

Annual Annual5

Change in analytes as noted above. During biennial sampling events (2018, 2020, etc.), the MSD sample will be collected from well SUD- A07-065. During the alternate annual sampling events (2019, 2021, etc.), the MSD sample will be collected from SUDWP-A07-01. The lab will be notified of the historical contaminant concentrations in these wells so that the MSD can be prepared at an appropriate level.

QC A7-Rinsate Blank VOCs, Pesticides, Total Metals, Cyanide

VOCs2, Pesticides, Cyanide

Annual (as needed) Annual (as needed)

Change in analytes as noted above. RB sample collected as needed, if non-dedicated sampling equipment is used. During biennial sampling events (2018, 2020, etc.), the RB sample will be collected following sampling of well SUD-A07-065. During the alternate annual sampling events (2019, 2021, etc.), the RB sample will be collected following sampling of SUDWP-A07-01.

(1) These changes to the 2015 LTMMP were implemented in 2017, in accordance with the recommendations in the 2016 Five Year Review (Sections 6.4.2, 6.5.3, 6.7) and the 2016 Annual Report.

(2) VOC COPCs only, which includes PCE, TCE, 1,1,2,2-tetrachloroethane, cis-1,2-DCE, and trans-1,2-DCE (Section 6.7 of the 2016 Five Year Review).

(3) Well replacement is planned for SUDWP-A07-01 during 2018 so that the sampling frequency may consistently occur in the fall.

(4) Biennial sampling beginning in 2018 (then 2020, 2022, etc.).

(5) The frequency of QC samples from the 2015 LTMMP has not changed: one duplicate and MS/MSD per sampling event; one RB as needed; one trip blank per cooler shipped with VOC samples.

(6) There are no changes from the 2015 LTMMP regarding water level measurements (water levels from 13 wells will continue to be measured during each LTM sampling event).

The fall sampling event will be conducted during the October-November timeframe.

KGS Page 2 of 2 October 2018