A Case Study: Emergency Response and Time Critical Removal Action for the Stony Hill Road Trichloroethylene (TCE) Site in Wake Forest, NC

Abstract

RHAME, KENNETH. Emergency Response, Removal Site Evaluation and Time Critical Removal Action for the Stony Hill Road TCE Site in Wake Forest, NC. A Case Study and Review of Actions Taken; under the Authority of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA); commonly known as Superfund. (Under the direction of Linda Taylor). TCE is a volatile organic compound (VOC) that is commonly used as an industrial solvent to remove grease from metal parts. It is also found in adhesives, paint removers, rug-cleaning fluids, spot removers, etc. (USEPA TEACH TCE). TCE is present in at least 852 of the 1,430 National Priority List sites identified by USEPA (ATSDR TCE ToxFAQs). The presence of TCE at the Stony Hill Road site is believed to be attributed to improper handling/disposal related to circuit board cleaning operations. The Stony Hill Road TCE site is not currently on the NPL. TCE is a designated hazardous substance as defined by 40 CFR 302.4 The United States Environmental Protection Agency (USEPA) classified TCE as a carcinogen to humans by all routes of exposure and determined it harmful to fetal development in 2011. It is these types of compounds that threaten public health and/or the environment that allow USEPA to initiate an action under CERCLA authority. CERCLA, also known as Superfund was enacted by Congress in 1980. Superfund created a tax on chemical and petroleum industries to establish a trust that could be used to address releases or threatened releases of hazardous substances that endanger public health or the environment. The appropriation for Superfund has expired and now most funding comes from either general tax revenues or by USEPA’s cost recovery efforts against responsible parties. Therefore the funding that is available to address environmental threats from year to year will vary and likely decline due primarily to the poor economic climate. It will become necessary to utilize critical thinking in decisions being made and to utilize outside resources effectively when response actions are initiated in the future. There are two types of response actions under CERCLA: 1. Removal Actions – short term actions taken that require a immediate or prompt response to address releases of hazardous substances 2. Remedial Actions – long term actions dealing with National Priority List (NPL) sites that significantly reduce the threats associated with releases of hazardous substances, but not immediately life threatening. The National Contingency Plan (NCP) provides policy and guidance necessary in responding to releases or threatened releases of hazardous substances. The NCP is the federal government’s doctrine for environmental emergency response actions. The NCP establishes three types of removal actions; emergency response, time-critical removals and non time-critical removals. The Stony Hill Road TCE site was addressed under CERCLA, consistent with the NCP and using both emergency response and time-critical removal action authority by the Federal On-Scene Coordinator (FOSC). In order for a site to meet the criteria to be addressed by the removal program, a concentration above a removal management level (RML) formerly known as the removal action level (RAL) must be documented. The RML for TCE was recently lowered from 128 parts per billion (ppb) to 8 ppb (USEPA, 1988 and USEPA RML Table 2012). The Stony Hill Road TCE site met the criteria as the TCE concentrations present in residential wells were documented as high as 340 ppb. A review of the decisions and actions taken at the Stony Hill Road TCE site as well as issues encountered and future recommendations in responding to exposures or threats of exposures resulting from hazardous substances affecting residential drinking water wells using CERCLA authority will be presented.