W&M Closes Contaminated Houston Site Through MSD
W&M conducted a property investigation and detected total petroleum hydrocarbons (TPH) in the C12-C28 boiling point range at concentrations in exceedance of the Texas Commission on Environmental Quality (TCEQ) Texas Risk Reduction Program (TRRP) residential assessment level (RAL).
Upon discovery of the contamination, the Affected Property was enrolled within TCEQ’s Industrial Hazardous Waste Corrective Action (IHW-CA) program. W&M conducted soil investigations at the Affected Property that identified TPH in exceedance of the critical protective concentration level (cPCL) the Site. W&M proceeded with a soil removal response action, backfilled the excavation with imported clean residential grade soil, and transported excavated soils to an off-Site facility for recycling. Through direct chemical removal to the full vertical and horizontal extent, the response action achieved the removal of TPH impacted soil and residual soil met the TRRP Tier I Remedy Standard A for residential use in all confirmation samples. The response action was completed in a single day and resulted in direct removal and permanent risk reduction.
Over the course of closing the Site, the TCEQ approved the Affected Property Assessment Report (APAR), Self Implementation Notice (SIN) for the response action and subsequent Response Action Completion Report (RACR) submitted by W&M. W&M submitted applications to the City of Houston and TCEQ for a Municipal Setting Designation (MSD), which restricted the potable use of groundwater and eliminated the groundwater ingestion exposure pathway (protecting the public from consuming the impacted groundwater). The COH conducted an administrative and technical review, and a public meeting and hearing were held to address the MSD process and any concerns citizens may have regarding it. Finally, after reviewing the MSD application, the TCEQ issued an MSD Certificate and a No Further Action Letter in October 2018, effectively closing the Site.
If you have questions about this project, please contact Jim Florey, P.G., CPSS, or Andy Adams, CHMM, CAPM. On July 25th, W&M experts Frank Clark, P.E., P.G. and Clayton Snider, P.G. will host a live webinar on Contaminated Site Closure Strategies. To register, please click here.