Former Landfill NPL Site and Wetlands Mitigation Project
As a result of remedial activities performed by ENTACT, specifically the installation of a landfill capping system and perimeter slurry wall, approximately 2.6 acres of palustrine emergent and scrub/shrub wetlands were impacted. In accordance with Section 404 of the Clean Water Act, wetland mitigation was required as compensation for the impacted wetlands. Based on a mitigation ratio of 1.5:1 for the palustrine emergent wetlands and a 4:1 mitigation ratio for the palustrine scrub/shrub wetlands, a total of 6.48 acres of mitigation wetlands were created on a property adjacent to the landfill site.

Habitat Restoration Details:
ENTACT completed construction and grading of the wetlands footprint, including construction of an access entrance road, erosion and sediment control installation, clearing, grubbing and staking out the footprint of the mitigation wetland , and removal of 78,000 bank cubic yards (bcy) of overburden soils. After overburden removal activities ENTACT placed and graded 28,560 cubic yards of topsoil. Finish grading activities consisted of constructing dry shelves and low flow trickle channels, installation of water flow channels, and placement and preparation of a one foot topsoil layer. Maximum flow in channels during seasonal events were projected to be 1 – 2 feet. Following final grading activities 425 live plugs were installed within the flow channels (Duck Potato, Lizards Tail, Blue Flag, Soft Rush, Bur-Reed) and 600 ½” to 1” uplands shrubs/trees were planted in the shelves (Primarily Poplar, Red-Osier dogwood, Pussy/Black Willows, Tag Adler).

Former Smelter NPL Site
ENTACT completed remediation activities at this former smelter that included excavation, on-site treatment, and off-site disposal of over 110,000 tons of lead-impacted soils and sediments; excavation of impacted sediments from Army Corps of Engineers drainage channel and East and West Streams adjacent to the site; installation of storm water management controls upgradient and/or downgradient of identified excavation areas; performed careful removal of impacted sediment to reduce potential for sediment suspension; mixing of saturated soils in staging area to promote evaporation of entrained water; and site restoration including seeding of affected stream banks, and wetlands restoration.

Habitat Restoration Details:
Characterization samples were collected from the stream bed of the West Stream and Army Corps of Engineers drainage channel at a frequency of 1 sample every 100 linear feet to determine if lead concentrations exceeded the cleanup criteria. Those areas of the stream bed determined to exceed the cleanup criteria for lead were excavated using a long-stick hydraulic excavator to a distance of 50-feet in the West Stream and 25-feet in the Army Corps of Engineers drainage channel on either side of the characterization sample location. Excavation depths averaged approximately 6 inches. The palustrine forested wetlands, palustrine scrub/shrub wetlands, palustrine emergent wetlands, and open water areas associated with the West Stream and the site were replanted per the requirements of the Wetlands Mitigation Plan developed by the Site Engineer. Emergent herbaceous species, such as soft rush and rice cutgrass, were located within 10 feet of the stream bank. Scrub/shrub species, such as arrowood, silky dogwood, and highbush blueberry, were planted within 10 to 25 feet of the stream bank. Forested and scrub/shrub species, such as swamp white oak, red maple and pin oak, were planted at distances greater than 25 feet from the stream bank.