New York
This project is located at the site of a former manufactured gas plant (MGP) where historical MGP operations were conducted between 1899 and 1931, primarily including the production of manufactured gas using the Lowe carbureted water gas process. COCs include MGP-related coal tar and associated compounds including benzene, toluene, ethylbenzene, xylenes (BTEX) and PAHs.
Sevenson self-performed the installation of 417 LF of sheet piling for NAPL barrier wall installation; removed 1,106 tons of debris, including sunken barge artifacts; mechanically dredged 8,772 CY of contaminated sediment; and placed 9,381 CY of sediment cap across a 3.6-acre area. The cap consisted of river backfill, engineered cap (sand and Organoclay mixture), and coarse sand. Crews managed the transportation and disposal of 11,903 tons of sediment and debris which traveled via barge 65 miles downstream to an off-site disposal facility.