The New York State Department of Environmental Conservation (DEC) will hold a public meeting at 7 p.m. on Tuesday, March 11 to present its plan for remediation of soil and groundwater contamination at the 123 Post Avenue Inactive Hazardous Waste Disposal Site. The meeting will be held in the Westbury Community Center located at 360 Post Avenue.

The 123 Post Avenue site consists of a 50-foot by 189-foot lot located in a densely populated commercial/residential area. The site contains a one-story, 3,500-square foot masonry building built in 1949. It has been operated as a dry cleaning facility since the 1950s. Illegal dumping and poor housekeeping resulted in the disposal of perchloroethene (PCE), a hazardous waste. This waste has contaminated soils, groundwater and indoor air at the site. It has also contaminated groundwater beyond the boundaries of the site.

DEC has divided the site into two operable units. An operable unit represents a portion of the site remedy that for technical or administrative reasons can be addressed separately to eliminate or mitigate a release, threat of release or exposure pathway resulting from the site contamination. Operable Unit1 (OU-1) consists of the 0.2-acre dry cleaner property and the groundwater under the dry cleaner property. The proposed remedial action plan to be discussed on March 11 addresses only OU-1. The other operable unit for this site, OU-2, consists of off-site contaminated groundwater. OU-2 is the subject of an ongoing state-funded groundwater investigation.

In September 2001 the site owner agreed to implement a full remedial program, including remedial investigation and remediation of OU-1. The remedial investigation fieldwork was begun in October 2000. While the investigation was in progress the site owner installed an interim remedial measure to address elevated levels of PCE in buildings to the north and northwest of 123 Post Avenue, as well as the elevated levels of contamination in soils.

An interim remedial measure may be conducted at a site when a source of contamination or an exposure pathway can be effectively addressed before completion of the remedial investigation. Interim remedial measures undertaken at 123 Post Avenue include installation of a soil vapor extraction system to remediate contaminated soils and installation of portable air purifiers to remediate contaminated indoor air. The soil vapor extraction system has proved successful in removing PCE from contaminated soils, and indoor levels of PCE have dropped below State Department of Health guidelines. Indoor air is being monitored quarterly to ensure that the remedial measures continues to mitigate the impacts to indoor air.

Levels of contaminants in the onsite groundwater dropped dramatically during the course of the investigation to levels near or below groundwater standards. Therefore, DEC is proposing no further remedial action for the onsite groundwater although the soil vapor extraction system would continue to operate to remove contaminants from the soil. The site owner has developed an air sparging plan that will be kept as a contingency in case groundwater contaminant concentrations rebound.

At the March 11 meeting, DEC and State Department of Health staff will review the history of the site and describe the results of investigations completed to date and the rationale behind the current proposal. Meeting participants will be given the opportunity to ask questions on the plan and to make comments. Written comments may also be submitted to Thomas Gibbons, project manager, NYSDEC, 625 Broadway, Albany NY 12233-7015. Comments must be received by March 23, 2003.

Copies of the proposed remedial action plan, investigation reports and other site documents are available at the Westbury Memorial Public Library and at the DEC's regional office in Stony Brook. Information is also available at www.dec.state.ny.us/website/reg1/hazwaste.html or by calling Mark Lowery of the DEC at (631) 444-0350.