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CDW CONSULTANTS, INC. |
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CIVIL & ENVIRONMENTAL ENGINEERS |
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ABOUT |
QUALIFICATIONS |
SERVICES |
PROJECTS |
CONTACT |
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▼ |
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Representative Environmental Projects |
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Cohasset Water
Commission, Assessment & Remediation, Cohasset, MA |
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| This
Site is the location of a pump house for an inactive municipal drinking
water wellfield which had remained unused for at least 20 years. Contaminated soil was discovered under
the building slab during the demolition of an old pump house. The suspected source of contamination was
from former diesel powered pump equipment.
The release area was located within a Zone II for the water supply,
therefore contaminant plume delineation and successful Site remediation was
important. CDW performed remedial
activities including the excavation and off-site disposal of approximately
400 cubic yards of impacted soil. A
monitoring well was subsequently installed adjacent and downgradient of the
excavation area. Two rounds of
groundwater analysis indicated that concentrations of petroleum compounds
decreased to below applicable standards and a Class A-2 RAO was prepared to
achieve regulatory closure. A new
pump house was constructed in it’s place for possible use of the wellfield
as a backup municipal water supply in the future. |
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© 2008 CDW Consultants, Inc. |
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