Former Bulk Fuel Terminal and Distribution Facility
Scope included excavation, stockpiling, and reuse of
over 75,496 cubic yards of overburden; on-site
crushing and
reuse of over 30,000 tons of concrete; excavation,
stockpiling and off-site disposal via rail of 205,000
tons of petroleum
impacted material; demolition of over 75,000 square
feet of on-site structures; installation of an
8-inch water
line; cleaning and removal or in-place abandonment
of underground piping that ran through the site,
as well
as an additional 5 miles that ran beneath city streets
to the formal terminals; management of recovered product;
backfilling and restoration of city streets; and site
backfill and restoration. Due to the proximity to the
bay (<500 feet) and the depth of excavation (up to 21 feet bgs), a perimeter dewatering
and sump system consisting of sixty-four (64) temporary
dewatering wells and six (6) mobile sumps was installed
around the perimeter of the excavation zone to minimize
water infiltration. Over 48 million gallons of water
was collected and treated for petroleum hydrocarbons
and suspended solids at a rate of up to 1,000 GPM prior
to discharge into the sanitary sewer.
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Sediment Removal Project
Project scope includes the excavation, handling, transportation and disposal
of 800,000 tons of PCB impacted materials and total material handling of over
1,200,000 tons. ENTACT is additionally responsible for the construction of
a 40-acre onsite landfill. Other remediation activities include the complete
excavation and restoration of ancillary runoff tributaries from the plant.
Remediation activities include extensive construction of access/haul roads
in and around creek and flood plain areas to enable ingress and egress to
the removal
areas; the construction of loadout areas ranging in size from 3.5 acres to
6.5 acres to expedite the transport of impacted material; and the construction
of
diversion channels, 2 miles in total length, to enable sediment removal from
the creek bed and flood plain. Water management is a 24 hours a day, 7 days
a week activity that includes containment and treatment of millions of gallons
of water in contact with the impacted areas. Two (2) 1,000 GPM water treatment
systems were designed and installed by ENTACT, and operated simultaneously.
The
systems involved initial settlement through an interconnected series of ten
or more baffled 20,000 gallon frac tanks, skimmer removal of free product,
polymer injection to promote settling,
solids removal via sand vessels and bag filters, and removal of dissolved organics
via carbon adsorption vessels. |
| Metals Precipitation - Metals precipitation from contaminated water involves the conversion of soluble heavy metal salts to insoluble salts that will precipitate. The precipitate can then be removed from the treated water by physical methods such as clarification (settling) and/or filtration. The process usually uses pH adjustment, addition of a chemical precipitant, and flocculation. |