NYSEG project, dredging will exceed $10M

PENN YAN--Construction crews at New York State Electric and Gas' (NYSEG) former Penn Yan manufactured gas plant (MGP) site are in the process of wrapping up stabilization work to prepare for dredging in the coming months. NYSEG representatives said the effort to dredge contaminated soils from the Keuka Outlet is expected to begin this summer as the workers finish up on the Lake Street site. The entire project cost is expected to exceed $10 million for both the building site work and dredging.
NYSEG Corporate Communications Manager Clayton Ellis said the building stabilization work has been completed and the MGP holder has also been removed. Last week, construction crews were busy spreading clean soil delivered to the site by dump trucks. This soil is being used to backfill areas that have been excavated. There is also a steel sheet piling located on the outlet side of the property, which Ellis said is stabilizing the site during the project.
Ellis said in general, the site excavation included the removal of two feet of soil. However, he noted some areas had more material removed because of the depth of impacted soil or the removal of the former gas holder foundation. In all, Ellis estimates approximately 6,000 cubic yards of material has been removed from the site around the building.
The manufactured gas plant was constructed in 1899 and operated until 1931. The operating companies included the Penn Yan Gas Light Company (1889 through 1926) and the New York State Central Electric Corporation (1927 through 1931). Gas was distributed to consumers through buried mains and used primarily for illumination. The prime contaminants from the former plant include coal tar, ash and purifier waste.
According to NYSEG, excavated contaminated soils are transported off-site to a thermal desorption facility located in Fort Edward. The same will be done with the dredged sediments and soils, which will be dewatered on-site. Ellis said the treated soil is used for a variety of uses, such as road construction. The concrete and other structures that were removed during the work were broken down and disposed offsite at Seneca Meadows Industrial Waste Landfill in Seneca Falls.
The dredging will take place throughout the area between the Liberty Street and Main Street bridges. Ellis noted the majority of upland soils will be removed prior to sediment dredging. He added the upland area of the site will be used to support the sediment dredge work through to the end of the project. The railroad trestle will also be removed prior to beginning sediment removal work.
"The dredging will include the removal of two feet of sediment," Ellis said. "However, dredging will be deeper as needed to remove impacted sediment. Approximately 8,000 cubic yards of sediment will be removed from the outlet."
NYSEG estimates the project will be completed in 2018. Ellis noted there are not any current plans for the building's use once the project is complete.