Loading...
600 LORING AVENUE - PUBLIC INVOLVEMENT NOTIFICATION ENVIRONMENTAL C o N E c O ECOLOGICAL SURVEY Engineers & Scientists CIVIL December 5,2024 RECEIVED Coneco Project No. 12519.002 Sara Moore,Chairperson DEC 12 2024 98 Washington Street 3rd Floor CITY OF SALEM Salem,Massachusetts 01970 BOARD OF HEALTH RE: Public Involvement Notification Phase I Initial Site Investigation and Tier I Classification Report Non-PCB Mineral Oil Dielectric Fluid Release Pad-Mounted Electrical Transformer 600 Loring Avenue Salem,Massachusetts Release Tracking Number 3-38449 Dear Chairperson Moore: Pursuant to 310 CMR 40,1403 of the Massachusetts Contingency Plan(MCP),the following serves as written notification of the submittal of a Phase I Initial Site Investigation and Tier I Classification Report. This submittal is regarding a release of non-polychlorinated biphenyl(non-PCB)mineral oil dielectric fluid(MODF)that occurred from a pad-mounted electrical transformer formerly located at the above-referenced location. A copy of the above-referenced report will be available for viewing on or about December 5,2024,at the Department of Environmental Protection Northeast Regional Office (MassDEP-NERD)in Woburn,Massachusetts. A copy of this report may also be obtained by contacting the undersigned in writing. A copy of the Phase I Initial Site Investigation summary of findings and conclusions is appended to this notice. A legal notice regarding this release will be published in The Salem News on or about December 5, 2024. A copy of this notice is included with this letter. A copy of the Disposal Site Plan is also attached for reference. Additional Public Involvement Activities may be requested pursuant to 310 CMR 40.1403(9). This submittal is being made on behalf of Massachusetts Electric Company (MECO),the party conducting response actions relating to this release. If you have any questions, please contact the undersigned. Respectfully Submitted, Coneco Engineers& Scientists,Incorporated kmf �W; I C Nicholas R. Holtgrefe Brain F. Klingler,PG,LSP Project Manager Principal Geologist RAF:NRH:BFK jw U:\\12519.002 Municipal_Notice_PhaseI_TierI Enclosures: Copy of Phase I Initial Site Investigation Summary of Findings and Conclusions Copy of Notice of Initial Site Investigation and Tier I Classification Disposal Site Plan cc: MECO MassDEP-NERD 4 First Street,Bridgewater,MA 02324 (508)697-3191 (800)548-3355 Coneco.com Summary of Findings and Conclusions of Phase I Initial Site Investigation Non-PCB Mineral Oil Dielectric Fluid Release Pad-Mounted Electrical Transformer 600.Loring Avenue Salem,Massachusetts Release Tracking Number 3-38449 Conditions of the area impacted by a historical release of non-PCB MODF from a 150 kVA pad- mounted electrical transformer formerly in use at the commercial property located at the 600 Loring Avenue in Salem, Massachusetts,were evaluated in a manner consistent with applicable guidelines for a Phase I-ISI as presented in 310 CMR 40.0480 of the MCP. Response actions performed in association with RTN 3-38449 included a review of pertinent Disposal Site history,the removal of approximately 5 cubic yards of remediation and investigation-derived waste,the advancement of five soil borings,the installation of five groundwater monitoring wells, and the collection and laboratory analysis of soil and groundwater samples. Based on the information and observations described herein,the following is a summary of the investigation findings: • On August 7,2023,MECO identified staining indicative of a historical release of non-PCB MODF from a 150 kVA pad-mounted electrical transformer. Coneco visited the Site and observed approximately 10 square-feet of surficial staining on the concrete transformer pad and adjacent soil. No indication of a sudden release of MODF greater than the applicable RQ was observed by MECO or Coneco. • The MODF associated with the leaking transformer was confirmed to be"non-PCB"in accordance with 40 CFR 761.3 and 310 CMR 40.0000. • In order to eliminate the source of the release and stabilize environmental conditions at the Site, MECO de-energized and removed the leaking transformer(i.e.,eliminated release source)on August 7, 2023. • On August 7 and 8,2023,approximately 3 cubic yards of impacted media were removed as part of initial LRA activities. Due to safety concerns associated with the structural integrity of a nearby utility pole,wooden retaining wall, fire escape foundation,and customer concerns with an extended electrical outage and an impending storm event,remedial excavation activities were suspended on August 8,2023. • Laboratory analytical results identified concentrations of EPH in excess of the applicable Method 1 Risk Characterization Standards in soil samples collected at the termination of LRA excavation activities. • On December 5,2023,Coneco submitted a BWSC-103: RNF to MassDEP,and RTN 3-38449 was assigned to the release. • On February 8,2024, five soil borings were advanced at the Site, and three of which were conservatively completed as groundwater monitoring wells. Results of laboratory analysis of selected soil samples collected from the two soil borings indicated that no concentrations of EPH were detected in excess of the applicable Method 1 Risk Characterization Standards. • On February 12,2024,Coneco returned to the Disposal Site to gauge the newly installed monitoring wells. Due to shallow refusal of Geoprobe test borings and limited presence of groundwater within the monitoring wells,the wells were considered not viable nor sufficient to characterize Disposal Site conditions • On July 19 and 22,2024,two of the original monitoring wells installed on February 8,2024, were replaced with new monitoring wells and two additional groundwater monitoring wells were installed to further delineate the potential extent of non-PCB MODF impacts to groundwater. • On July 23,2024, Coneco returned to the Disposal Site to gauge the newly installed monitoring wells. Based on the observation of LNAPL having a thickness of approximately 6 inches within monitoring well CMW-02R,release conditions were considered to represent a 72-hour Reportable Condition as described in 310 CMR 40.0313(1). MassDEP notification was completed within 72 hours of the identification of a reportable condition in accordance with the specifications of 310 CMR 40.0332. At the time, MassDEP-HERO provided verbal approval to conduct IRA activities. RTN 3-50554 was assigned to the release by MassDEP. • IRA activities performed at the Disposal Site associated with RTN 3-50554 since July 2024,have included monthly monitoring well gauging,LNAPL removal from monitoring well CMW-02R, proper off-Site disposal of recovered LNAPL, and quarterly groundwater sampling of select monitoring wells at the Disposal Site. • IRA activities,consisting of the further assessment of the nature and extent of remaining non- PCB MODF impacts and potential remediation of impacted soil and/or groundwater,will continue at the Disposal Site in accordance with the IRA Plan associated with RTN 3-50554 dated September 24,2024. • The release occurred from a point source at a commercial property. The potential routes for human exposure include inhalation, ingestion, and/or dermal contact with soil during activities such as landscaping,utility maintenance,or construction conducted within the limits of the Disposal Site. • No surface water, drainage structures,and other potentially sensitive potentially sensitive environmental receptors are known to have been impacted by the subject release. Based on the evaluation of current Disposal Site conditions in relation to the Tier I Inclusionary Criteria,performed in accordance with 310 CMR 40.0520(4),the Disposal Site meets the criteria for Tier I Classification. NOTICE OF PHASE I INITIAL SITE INVESTIGATION AND TIER I CLASSIFICATION Non-PCB Mineral Oil Dielectric Fluid Release Pad-Mounted Electrical Transformer, 600 Loring Avenue Salem, Massachusetts Release Tracking Number 3-38449 A release of oil and/or hazardous material has occurred at this location, which is a Disposal Site as defined by M.G.L. c. 21 E, § 2 and the Massachusetts Contingency Plan, 310 CMR 40.0000. To evaluate the release, a Phase I Initial Site Investigation was performed pursuant to 310 CMR 40.0480. As a result of this investigation, the site has been classified as Tier I pursuant to 310 CMR 40.0500. On December 5, 2024, the Massachusetts Electric Company filed a Tier Classification Submittal with the Department of Environmental Protection (MassDEP). To obtain more information on this disposal site, please contact Brian F. Klingler, PG, LSP, Coneco Engineers& Scientists, Incorporated, 4 First Street, Bridgewater, Massachusetts 02324, (508) 697-3191. The Tier Classification Submittal and the Disposal Site file can be reviewed at the MassDEP Northeast Regional Office, 150 Presidential Way, Woburn, Massachusetts 01801, (978) 694-3200. Additional public involvement opportunities are available under 310 CMR 40.1403(9) and 310 CMR 40.1404. �.rom.� cgLM acres s aamuw oe�mm MAN=grNz asyseN stslt�noS sia8u� v 5 Nv�a arcs aysoasia ;� O O 3 r a�[NM aawnon-ara Nm munom nva row xBram'OF 9Od-NON v sxos✓� Sg 6 B 3 U o gU G it - Wow ROAMING WALL r - Y'i u t 1�< \ I I I y f Sk if �l 1 . ` rc J �3 T—L- 0 !n I 1 I U Z F o ✓. N PZ 0/41 V1 13 5�yyy Ki Ka.2--3 goy N zz � Z� W�Wj Gj U q�q jg R.a R�o>O>o> S tf 3 o � do ytl €a$ ¢W ZLD off' o�d ia€ F � I ��nn 33 Z y Z3 zSQi zq�Z os �� 1 zjz(z i W b as o¢0 8$ I I I I I U iliiNYY U 00 < � a a :�"_ N a�