S A B I N E R I V E R A U T H O R I T Y INTEROFFICE MEMORANDUM
DATE: May 28, 2014
TO: Sabine River Authority of Texas Board of Directors
CC: Executive Staff, Jim Brown, John Payne, Division Managers
FROM: Mary S. Vann, Manager Environmental and Information Resources
SUBJECT: Caddo Creek Special Investigation for Metals
Reports of a bad odor at a self-storage facility just southwest of Greenville on IH-30 led to an investigation by the Hunt Count y Office of Homeland Security (OHS). The Hunt County OHS notified EPA, TCEQ, TPWD, and SRA on 5/15. The proximity of the storage facility to a drainage ditch which empties into an unnamed tributary and thence into East Caddo Creek just downstream of IH-30 prompted SRA to initiate a special investigation of its own. On 5/15, Upper Basin Field Office (UBFO) staff sampled four Caddo Creek (East Caddo Creek and Caddo Creek) sites downstream of the storage facility. UBFO also sampled two East Caddo Creek sites upstream of the storage facility and a South Fork Sabine River site to serve as reference samples—water of similar water quality but outside of any potential impact from the storage facility. Two maps showing the sample sites in relation to the storage facility and Lake Tawakoni are attached. The Environmental Services Division (ESD) Water Quality Laboratory analyzed the samples for total metals on 5/19 – 5/21. The total metals samples were analyzed using ESD’s ICP-MS, an instrument capable of measuring metals concentrations to very low levels (parts-per-billion or ppb). Mercury samples were sent to another laboratory since ESD does not perform mercury analysis. Results for Arsenic, Barium, Cadmium, Chromium, Lead, Selenium, Silver, and Mercury at the four Caddo Creek sites were compared to compiled historical Lake Tawakoni metals data, TCEQ groundwater metals limits, and the three reference sites. The Caddo Creek metals results indicated no cause for concern. The median concentrations of the Caddo Creek metals were at concentrations below the TCEQ groundwater limits and the Lake Tawakoni historical metals compilation with one exception: the median Barium result was slightly higher than the Lake Tawakoni Historical Barium data. The difference in the Barium concentrations is insignificant, however, because the overall concentration of Barium was extremely low and more than 200 times lower than the TCEQ groundwater limit for Barium. Compared to the three reference sites, the median concentration of each metal from the Caddo Creek sites was not significantly different from the reference sites. The metals analysis demonstrates no discernable impact from the self-storage facility to Caddo Creek. ESD will follow-up in June with another sample collection at the Special Investigation sites. In addition, ESD will also sample Lake Tawakoni for dissolved and total metals in June. Please contact me at (409) 746-2192 or [email protected] for more information.
______Mary S. Vann Manager, Environmental and Information Resources