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Wellesley College -
Former Henry Woods Son's Paint Factory Phase I: Upland/Wetland/Pond Remediation Maxymillian Technologies, Inc. (MT) was selected as the remediation contractor for the former Henry Woods Son's Paint Factory site located at Wellesley College in Massachusetts. This large-scale and fast-tracked project involved installing extensive sheet piling and cofferdams, waterway diversion, on-site consolidation area construction, contaminated sediment dredging excavation, and dam rehabilitation. To prepare the site for remediation, MT installed a turbidity control system in Lake Waban, preventing the migration of sediments. MT then furnished and installed diversion piping from Paintshop Pond extending down to Lake Waban. The diversion system consisted of three pumps connected to two lengths of 24" HPDE piping running along the western side of Paintshop Pond. Each of the two lengths of diversion piping was 2400 linear feet. The three pumps ran at full capacity for most of the project, pumping 14-15,000 gpm. MT constructed a velocity dissipater to minimize erosion where the diversion pipes emptied into Lake Waban. Prior to removing source soils from Paintshop Pond, MT installed sheeted cofferdams with sealed joints in order to excavate in the dry. MT activated the Paintshop Pond diversion pumps, diverting any inflow to Paintshop Pond, and then drained the pond. A cofferdam was also installed in Lake Waban. With both cofferdams in place, MT commenced excavation operations. MT began excavation activities in the Paintshop Pond area, excavating 7,000 cy of wet soils using MT's long reach excavator. Approximately 230,000 cy of soil and sediment was excavated from the area for use as backfill and in the construction of a consolidation area. 7,000 CY of wet soils were excavated from the Lake Waban area under a MA DEP contract. In total, MT excavated approximately 300,000 cubic yards of soil and 75,000 cubic yards of sediment from the site. An innovative, MT-designed clamshell bucket mounted on the long reach excavator was used to remove the contaminated soil and sludge from the sensitive wetlands areas. The clamshell bucket minimized disturbance to the wetlands while maximizing the amount of sediment removed. The excavator was also equipped with a Global Positioning System (GPS) to provide precise control of dredging operations. Following excavation of contaminated material from both the Paintshop Pond and Lake Waban areas, MT placed them in the on-site consolidation area. MT placed woven geotextile and sand borrow to prepare for HDPE liner and geocomposite installation. MT also installed a detention basin and a storm drainage system. The final stage of the project involved the rehabilitation of the Paintshop Pond dam and the construction of concrete retaining walls. MT excavated and transported borrow and wetlands material to form an on-site consolidation landfill with a capacity of 180,000 cy. MT excavated, placed, compacted and graded the consolidation area as the materials were brought in. MT utilized the GPS System survey equipment for placement and verification of this material. MT installed a geotextile layer followed by a 6-inch sand layer over the area to cap the materials and an anchor trench was excavated. MT then installed a 60-mil HDPE liner, with stringent QAQC requirements, a geocomposite drain layer, and perforated pipe. A metallic strip indicator was placed at the cap's edge. To finish MT's portion of the landfill, a 2 foot layer of borrow was installed. To complete the project, MT backfilled disturbed areas with clean fill excavated from the site. MT performed grading and shaping activities, placed new native plantings and seeded the designated areas to restore the original wetland.
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above: Driving sheets from barge below: Dredging Lake Waban with Clamshell Bucket from barge 
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