Source: http://www.newrochelletalk.com, January 11, 2016
NEW ROCHELLE, NY — The New York State Department of Environmental Conservation (NYSDEC) is reviewing the Remedial Investigation Report for the Schmuckler’s Dry Cleaners site located at 358-364 North Avenue, New Rochelle, Westchester County.
NYSDEC is reviewing the “Remedial Investigation Report” that was submitted by HNJ Realty. The report describes the results of the site investigation and recommends development of a remedy to address the contamination that was found. Based on the findings of the investigation, NYSDEC, in consultation with the New York State Department of Health (NYSDOH), has determined that the site poses a significant threat to public health or the environment due to elevated concentrations of contaminants in groundwater, soil, and soil vapor. The activities in the report have been designed to address the identified contamination and the threat posed.
A Remedial Investigation took place between 2007 and 2015. Soil borings, monitoring wells in both overburden and bedrock, and sub-slab vapor and soil gas points were installed both on- and off-site during the RI. The primary contaminants of concern at the site are: 1) chlorinated volatile organic compounds (CVOCs), primarily tetrachloroethylene (PCE), tricholoroethene (TCE), and cis-1,2-dichloroethene (cis-1,2-DCE); 2) petroleum-related volatile organic compounds (VOCs); and, 3) semi-volatile organic compounds (SVOCs). CVOCs and petroleum-related VOCs were observed in soils, groundwater, sub-slab vapor, and soil gas. SVOCs were observed only in groundwater.
Concentrations of PCE and TCE in groundwater and sub-slab soil vapor underneath the on-site building suggest the presence of these contaminants as free product. Up to six inches of petroleum-based floating product was observed atop groundwater underneath the basement slab of the on-site building. The extent of contamination appears to be concentrated underneath the on-site building at the location of the former dry cleaning equipment room and just outside the back door at the location of a dry well. However, the floating petroleum product in groundwater extends off-site in the downgradient/southeasterly direction.
As part of an Interim Remedial Measure, a soil vapor mitigation system was installed under the poured concrete slab of the on-site building’s basement. The system is a combination sub-slab depressurization system (SSDS) and a soil vapor extraction (SVE) system which addresses both soil gas mitigation and remediation of contaminated material. The installation, testing, and replacement of the blower for the IRM SVE/SSDS system occurred between late 2008 and 2012. The IRM Construction Completion Report was approved in October 2013. In addition, a second IRM is in progress at the site. A May 2015 IRM work plan for an in-situ treatment pilot study was approved. Biological reagents were injected at a point adjacent to the former dry cleaning equipment room to break down both VOCs and SVOCs. Contaminant concentrations in groundwater and pilot effectiveness will be evaluated over time. NYSDEC will complete its review, make any necessary revisions and, if appropriate, approve the investigation report. The approved report will be made available to the public. The applicant may then develop a cleanup plan, called a “Remedial Work Plan.” This plan describes how contamination will be addressed, with NYSDEC and NYSDOH overseeing the work. NYSDEC will present the draft cleanup plan to the public for its review and comment during a 45-day comment period.
NYSDEC will keep the public informed throughout the investigation and cleanup of the site.
Background
Location: The Schmuckler’s Dry Cleaners site is located in an urban area located at 258-364 North Avenue in New Rochelle, Westchester County. The site is 0.21 acres, most of which is covered by a two-story row building with a full basement. Site Features: In addition to the former dry cleaners, historically located on the first floor, the site also includes an enclosed backyard area to the immediate west of the building. The backyard is mostly covered by lawn, but also includes elevated planting beds, and a paved walkway.
Current Zoning/Use(s): The site is commercially zoned, and currently has five commercial tenants occupying both the first and second floors. Properties along North Avenue are predominantly zoned for commercial or mixed use, some maintaining residential apartments above. Commerical uses dominate areas within one block east and west of North Avenue with the exception of a multi-unit residential building immediately to the west of the site. Drinking water on-site is provided from a municipal source.
Past Uses of the Site: The building on-site was built in 1891, and operated by Schmuckler’s Cleaners from 1914 to 2006 on the first floor and basement of the building. Additions were added to the building in 1937, and two in 1987. The site was acquired by the Volunteer, HNJ Realty, LLC, in August 2005, and entered into a Brownfield Cleanup Agreement with NYSDEC in June 2006.
Site Geology and Hydrogeology: The site is underlain by fill which is underlain by poorly sorted glacial material (silty-clay with sand and gravel). The highly weathered bedrock surface is between 9 and 13 feet below ground surface at site. Groundwater was encountered between 9 to 12 feet below site. Bedrock groundwater flows to the southeast. Only two overburden wells onsite have produced water, therefore a groundwater flow direction in overburden cannot be determined. It is assumed that it flows in the same basic southeast direction as the bedrock groundwater. Additional site details, including environmental and health assessment summaries, are available on NYSDEC’s website at: http://www.dec.ny.gov/cfmx/extapps/derexternal/haz/details.cfm?pageid=3&progno=C360088