United States Environmental Protection Agency
Region VI
POLLUTION REPORT

Subject: 

The former Big Tex Grain Site is located on a 7.5-acre lot in San Antonio, Bexar County, Texas, at 328 Blue Star Road.  The geographic center of the site is located at Latitude 29.405° North Longitude -98.492° West.

The Big Tex Grain Site has historically been associated with industrial activity, including operating a vermiculite exfoliation plant, grain production, and sawdust warehousing.  The EPA Region 6 office performed an assessment of the subject property to determine potential impact to human health and the environment based on the transporting of vermiculite from Libby, Montana, to the W. R. Grace vermiculite exfoliation plant in San Antonio, Texas. The property has been listed in the EPA CERCLIS database since 2000.

The site consists of approximately 31 structures including the Big Tex grain elevators and warehouses on the eastern portion of the property.  To the north-northwest of the site, there are numerous grain silos that were converted into office spaces.  The site is bounded to the south and west by Union Pacific railroad tracks and to the north and east by the San Antonio River.  The site is secured by a chain link and barbwire fence extending around the entire perimeter of the facility.  Within the facility exposed soil areas are heavily vegetated, but still accessible.  The Big Tex Grain Site is scheduled to be developed into a “Mixed Use” facility.

USEPA/START continued Activity Based Sampling after allowing the site to dry for 72 hours.  To reduce the amount of volume being collected within the sample media, START conducted Activity Based Sampling for 50 minutes rather than the proposed 100 minutes.  

Upon review of the 50 minute Activity Based Samples by the site Microscopist, it was determined that START could increase the sample time to 75 minutes.  Two 100 minute Activity Based Sampling events were conducted at the end of the sampling event.  One location was determined to be adequate to send to the lab, but the other had overloaded sample media and could not be used.

USEPA/START will break down the site in preparation of demobilizing this phase of the Big Tex Grain Assessment.  START will mobilize the USEPA Mobile Command Post, and ship all equipment back to the appropriate vendors.

USEPA/START will await sample results from the lab.  Upon receipt of analytical results, START will work with USEPA OSC and USEPA ERT to determine the level of risk at the Big Grain Tex Site.  START will draft a report to illustrate the level of contamination utilizing aerial imagery and meteorological data collected at the site.

USEPA and START will determine the level of amphibole asbestos contamination at the Big Tex Grain Site.  This data will be used to determine if a potential removal action will need to be conducted.

START will need to get all the analytical results validated, and a final report drafted in a timely manner so that the USEPA OSC can determine if a removal action will be needed at the Big Tex Grain Site.