U.S. Environmental Protection Agency Air Treatment at Grenada Stamping - Information for Workers Fact Sheet #13 January 2018 Introduction On December 29, 2017, a treatment system intended to reduce elevated levels of trichloroethene (TCE) inside the manufacturing building at the Grenada Stamping facility (Facility) was restarted under an EPA removal action. Removal actions are short-term responses under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) intended to protect people from risks or potential risks associated with contaminated sites. The treatment system will operate with EPA oversight and monitoring. TCE contamination is present beneath the Facility as a result of spills from prior operations. Sampling indicates TCE vapors from beneath the concrete floor are rising into the building and there could be a risk to workers. The new treatment system will replace interim measures taken since January 2017 to increase ventilation. These have decreased TCE concentrations within the building. The new treatment system is a more reliable, long-term method to ensure TCE concentrations remain at acceptable levels. More information about EPA's ongoing work to oversee the cleanup of the site is posted at: www.epa.gov/grenadacleanup. Pilot Study and Air Permitting EPA previously directed the Facility to install the treatment system, known as a sub-slab depressurization system or "SSDS" (refer to Fact Sheet #11 for more detail). The Facility's contractor installed and operated the SSDS from August 12 to September 11, 2017, as a pilot study. Air sampling results before and after the pilot (summarized on page 2) showed the treatment system was effective at reducing TCE concentrations inside the building. As part of the pilot, potential annual emissions of hazardous air pollutants were estimated. Because the treatment system will operate under EPA's CERCLA authority, a state air permit is not required, however, the Facility will be required to meet the substantive requirements of such a permit. These include air sampling at multiple points of the air treatment system to verify effectiveness of the system and ensure emission standards are met. Summer/Fall 2017 Air Sampling Results EPA directed the Facility to perform multiple rounds of air sampling in and around the manufacturing building beginning in October 2016. The results of the most recent air sampling conducted from June to October 2017 are summarized below. Detailed results from all sampling performed to date are posted online. EPA ------- Summer/Fall 2017 Air Sampling Results (continued) Indoor Air Results Indoor air samples were collected from six locations inside the manufacturing building using traditional Summa canisters and Radiello® samplers that slowly draw air over a specified duration (24-hours, 7-days or 28-days). This yielded 55 samples (summarized in Table 1). Some results before the treatment system was turned on exceeded the removal management levels (RMLs) for sensitive and non-sensitive populations. RMLs are used by EPA to help determine if any future actions may be needed. A sample result higher than a RML by itself does not imply that adverse health effects will occur. Outdoor Air Results Air samples were collected using Radiello® samplers from outside of the manufacturing building over several durations (24-hours, 7-days or 28 days). TCE was detected in all 7 samples at very low levels below the indoor RML (there is no RML for outdoor air). Table 1: Summary of TCE Concentrations in Indoor Air inside of Manufacturing Building Sample Duration Sampling Date Removal Management Levels (RMLs)41 Range of Concentrations Detected 24 hour 6/28/2017 8.8/26 6.2-28 7 day 7/13 - 7/20/2017 8.8/26 6.1-11 28 day 7/13 - 8/10/2017 8.8/26 6.6-26 28 day 8/13 - 9/11/2017 8.8/26 0.93-6.4 24 hour 8/31/2017 8.8/26 <0.98-5.2 7 day 8/31 - 9/7/2017 8.8/26 1.7-2.4 24 hour 9/27/2017 8.8/26 3.1-7.8 28 day 9/11 -10/9/2017 8.8/26 2.0-7.6 Concentrations reported in micrograms per cubic meter ug/m3 *The Removal Management Level (RML) for sensitive Populations, which includes women of childbearing age, is 8.8 Mg/m3. The RML for non-sensitive populations is 26.0 ng/m3. Actions Being Taken An On-Scene Coordinator (OSC) was assigned to conduct a Removal Site Evaluation (RSE). The RSE consisted of a review of recent facility indoor air monitoring sample results and current status of the treatment system. The OSC determined that site conditions met the criteria for conducting a removal action. The OSC conducted a site visit on January 3, 2018, and verified the treatment system is operational. EPA will require the Facility to submit a sampling plan for the system itself in order to ensure the system is performing properly and that workers and the surrounding community are protected while the system operates. EPA continues to work with the MDEQ and the Facility to identify long-term measures to reduce and eventually eliminate the source of TCE contamination beneath the Facility. CONTACTS EPA Community Involvement Coordinator Abena Ajanaku 404-562-8834 ajanaku. abena (Sepa.gov EPA On-Scene Coordinator Steve Spurlin 731-394-8996 spurlin.steveffi epa.gov FOR MORE INFORMATION Website www.epa.gov/grenadacleanup Information Repository Elizabeth Jones Library 1050 Fairfield Avenue Grenada, MS 38902 ------- |