Contaminated Soil at GHS Must Be Removed

Soil samples collected from the area where Greenwich High School’s new auditorium is to be constructed show levels of PCBs that are above what is allowed under state and federal regulations — however it won't be known how much contaminated soil will need to be removed from the site until construction begins.

According to a Jan. 23 report from the Town’s environmental consultant (see attached PDF), AECOM, two of 16 soil samples taken last Oct.-Nov. from the site where the auditorium will be built had levels of PCBs above 50 milligrams per kilogram, thus those areas must be remediated (i.e. the soil must be removed), as per state and federal regulations. Soil with levels below 50 milligrams per kilogram can be addressed during the construction process, AECOM says in its report.

“Based on the results of this investigation, a remedial plan should be developed to address PCB-containing materials in accordance with the governing federal regulations under §761.61(a) and the governing state regulations for PCBs and the other COCs as well,” the report concludes. “However, prior to any construction activities, remediation of PCBs in soil [at or above] 50 mg/kg should be performed."

As per the regulations, testing of soils will be ongoing during construction to ensure “remedial goals have been achieved.” What’s more The Town will be required to “expand excavations as needed until remedial goals have been achieved.”

The Town is also required to conduct groundwater testing to ensure the soil remediation process doesn’t impact groundwater quality. Several homes near the high school are reportedly on well water.

The Town will also be required to “complete a plan to store, handle and dispose of waste in accordance with state and federal regulations” as well as a “decontamination plan for equipment used during the remediation of PCBs.”

In addition it will have to implement air monitoring during construction so as to protect site workers, other site users, and the surrounding community from potential exposure.

The testing of samples taken from the site of the auditorium is in addition to the testing of soil samples collected from the high school’s seven athletic fields in December. As reported by Greenwich Patch Feb. 2, that first round of testing has been completed — and the results have been submitted to EPA, DPH and DEEP for review and approval.

Approximately 150 soil samples, 30 sediment samples, 7 surface water samples were tested in the first phase, according to an update from the school district. The work also included the installation of four ground water monitoring wells.

“The goal is to receive approval for unrestricted use of all fields (1 through 7) by March 2012,” the district said in a statement last month.

The test results will define the scope of the cleanup, i.e. how much soil must be removed, and what the cost will be.

In September the Board of Estimate and Taxation and Representative Town Meeting approved $1.165 million for the additional environmental testing.

The contaminants were discovered in July after an area near the school’s west parking lot was excavated to prepare for the construction of the new auditorium, stalling progress on the $29 million MISA project before it even began (as well as disrupting outdoor sports activities and resulting in a temporary ban on student parking).

Although the MISA Building Committee is overseeing the auditorium construction project, the cleanup of the contaminated soil is being handled as a separate project overseen by the Department of Public Works.