Remedial Action Plan - Rochford Field - Newhall Remediation Project

In April 2001, M&E (CTDEEP subcontractor) collected and analyzed 37 surficial (0-0.25 ft)
soil samples from Rochford Field (T-1 to T-37) for analysis for SVOCs and metals and/or
waste disposal characterization parameters (VOCs, ETPH, total and leachable metals, and
polychlorinated biphenyls [PCBs]).
Results of the CTDEEP and M&E explorations found 2.75 ft to 8.5 ft deep fill deposits
containing a mixture of soil, slag, brick, cinders, wood, coal, rubber, cloth, clinkers, concrete
and metal pellets. An “odor” associated with a layer of black sand and cinders were recorded
at SS-26. Chemical testing of fill and soil samples detected ETPH, SVOCs and metals (copper,
nickel, arsenic, mercury, thallium, and lead) at concentrations in excess of Remediation
Standard Regulation (RSR) RDEC and/or GAPMC. Results of the groundwater analyses
detected SVOCs and metals (including beryllium, cadmium, chromium, copper, lead, nickel,
zinc, and mercury) in excess of RSR criteria. Results of the disposal characterization testing
also detected VOCs (chloromethane and methylene chloride), cyanide, and pesticides (4,4’-
DDD, 4,4’-DDE and 4,4’-DDT) below RSR criteria.
In 2002, Haley & Aldrich conducted a subsurface exploration program in Rochford Field including five
test pits (RF HATP1 through RF HATP5), fifteen test borings (RF HA108 through 119, RF HA121,
RF HA123 and RF HA124), and the installation of four monitoring wells (RF HA108MW, RF HA
110-MW, RF HA115-MW and RF HA123-MW). Results of the Haley & Aldrich investigations are
documented in 9 December 2002 reports entitled “Report on Phase II and III Environmental
Investigations, Rochford Field and Mill Rock Park, Hamden, Connecticut” and “Report on Test Pit
Investigations, Hamden Middle School, Rochford Field & Mill Rock Park, Hamden, Connecticut”.
Locations of the Haley & Aldrich explorations are shown on Figure 2. Results of chemical testing of
soils and groundwater are included in Tables Ia, Ib, IIa and IIb, respectively, along with results of
subsequent analyses. Results of the soil analyses detected widespread impacts from petroleum VOCs,
SVOCs, ETPH and metals within the fill material at concentrations in excess of RSR RDEC and
GAPMC. Chlorinated pesticides were detected at concentrations below RSR criteria. The groundwater
analyses detected SVOCs, ETPH, nickel and zinc at concentrations above RSR GWPC; contaminants of
concern were not detected above RSR Surface Water Protection Criteria (SWPC) or Residential
Volatilization Criteria (RVC).
From October 2004 to October 2005, Haley & Aldrich performed supplemental Phase III explorations
and chemical testing to determine the extent of environmental site impacts related to former filling
activities in the study area. This work was performed to further define the degree and extent of
contamination, and to develop a preliminary Remedial Action Plan (RAP) in compliance with paragraph
B.3.c.(1) of Consent Order SRD-128. The supplemental investigations included site screening with
subsurface interface radar, a metal detector and a magnetometer, excavation of four test pits
(RFHATP6 through RFHATP6) and drilling 19 test borings (RF-HA108D, RF-HA201 through RF-
HA212, RF-HA213A though RF-HA213E and RF-HA214; eight of the borings were completed as
monitoring wells (RF-HA-108MWD, RF-HA201-MW, RF-HA202-MW, RF-HA207-MW, RF-HA208-
MW, RF-HA209-MW, RF-HA211-MW and RF-HA-212MW (Figures 2A and 2B). Results of the
radar and magnetometer testing were used to locate the test pits; no evidence of buried drums or large
pieces of metal was detected. Results of the soil analyses detected SVOCs, ETPH, metals (arsenic,
antimony, beryllium, cadmium, chromium, copper, lead, mercury, nickel, selenium, silver, thallium
and zinc), leachable metals (antimony, arsenic, copper, lead and zinc), chlorinated pesticides, and low
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