The Helena Chemical Company (HCC) facility located in Mission, Texas, was used for pesticide formulation from 1950 to 1972. The facility is located in a primarily residential neighborhood and currently incorporates five structures within the property boundary (Attachment 2). Soil samples collected in 1980 from the HCC site and surrounding areas indicated elevated concentrations of various pesticides. A lawsuit was filed on behalf of the EPA against the two former owners of the facility, HCC and the Tex-Ag Company. As a result of the lawsuit, the former owners entered into a Consent Decree to remediate the contaminated properties. In 1982 the most highly contaminated soils on the HCC facility site were excavated to a depth of six inches below ground surface (bgs) and buried on site within a soil repository. The repository was capped by a six-inch layer of caliche that was overlain by a one-inch layer of asphalt. In 1983 a Federal District Judge in Brownsville, Texas, ruled that all cleanup activities specified in the Consent Decree had been carried out (Shaw 2004). The Texas Commission on Environmental Quality (TCEQ) remediated residential areas adjacent to the Site in August, 2003.
During the TCEQ remediation of the residential areas, they observed the weakness and failures of the cap. They contacted EPA’s Site Assessment Team to request a new Preliminary Assessment / Site Investigation (PA/SI) to be conducted at the site for Hazard Ranking System (HRS) analysis. The HRS analysis resulted with the Site not qualifying for inclusion on the National Priorities List (NPL). The Site was referred for consideration for a potential Removal Action due to the deteriorating cap.
EPA is finishing the demolition of the Above Ground Storage Tanks (ASTs) that were located on Site at the corner of N. Holland Ave. and W. Sixth St. The two ASTs were previously sampled and the contents identified as non-hazardous. One tank was empty while the other had a small amount of oily water. The removal of the non-hazardous tanks involved the clean out, cutting of insulation, and recycling at an approved facility.
An EPA community office trailer is available on Site. This office will allow the communities an opportunity to speak with and EPA representative in person about any questions or concerns they may have about ongoing Site activities. This office has up to date and current information available in both English and Spanish.
On Friday October 13, 2006 EPA contractors plan on completing the demolition of the AST #2. A concrete breaker has arrived on Site and will be used to demolish the slab that was used for the foundation of the warehouse building.
On Saturday October 14, 2006 EPA plans on breaking up a small section of the asphalt cap on Site to access the contaminated soil underneath. A network of air monitoring and air sampling devices will be used at and around the community during this process to measure air quality.
Completion of the second phase is the removal of the above ground storage tanks (ASTs), and building shed and warehouse demolition.
The start of the third phase will involve the removal of the asphalt cap and contaminated soil underneath. This phase will be the most time consuming. There is an estimated 15,000 cubic yards of soil will need to be excavated and characterized for disposal.
Health and safety concerns have been raised about dust that may be potential contaminated migrating offsite during the clean up process.
An extensive network of air monitoring and air sampling safe guards will be utilize on site and within the neighboring community. All scientific data will be quickly analyzed and made public for city and community leaders to review and discuss with the EPA. Wet demolition techniques will be used during building demolition to reduce and / or eliminate offsite migration of dust.
EPA will take every precaution in minimizing the level of dust accumulation during all site activities throughout the entire clean up process. EPA is committed to the public health and safety of it's workers and the neighboring community.
|
