Facility Audit: Deer Park, TX - Clean Harbors

B. Faulting
There are no faults crossing the Deer Park site, or the immediate vicinity. The Battleground
fault, the nearest fault to the site, is located several miles to the south and southeast. Like most
subsurface faults along the upper Texas Gulf Coast not associated with salt domes, the
Battleground fault has an east-northeast trend, which generally parallels the coastline. The area
is considered to have zero seismic activity.
C. Surface Water Hydrology
Intermittent streams and bayous are characteristic surface water features in the area surrounding
the facility. The only surface water feature on the Deer Park property is a channelized portion of
Tucker Bayou into which treated wastewater is discharged under the site's USEPA NPDES and
TCEQ permits. Tucker Bayou flows to the north for approximately 1.5 miles where it discharges
into the Houston Ship Channel.
From a water quality perspective, the usage of Tucker Bayou water is limited. Tucker Bayou
and the Houston Ship Channel are not used as sources for public water supply or for any
recreational purposes.
D. Groundwater/Historical Use/RFI
Groundwater quality assessment activities were initiated in 1985, when statistical analysis of
groundwater chemical data indicated contamination. Since then, extensive groundwater quality
assessment studies and a RCRA Facility Investigation (RFI) have delineated the site's
hydrogeology and groundwater make-up.
Regional geological studies indicate that the Chicot and Evangeline aquifers are regional sources
for drinking water and industrial process water. These two aquifers are located at 300 to 500 and
620 to 1500+ feet below the surface. The facility has two industrial wells completed in the lower
Chicot aquifer, and groundwater withdrawal is controlled by the Harris-Galveston County
Coastal Subsidence District. Analytical results indicate no detectable contamination in these
wells. The amount of groundwater pumped from these aquifers has no discernible hydraulic
influence on shallow groundwater at the facility. Thick clay layers separate the deep drinking
water from the monitored shallow sands.
Past activities at the Deer Park facility resulted in groundwater contamination in three subsurface
layers (Strata 1, 3, and 5). The contaminants of concern are chlorobenzene and a number of
volatile organics. As a result of this contamination, in October 1987, Deer Park entered into an
Administrative Agreed Order with the USEPA under 3008(h) of RCRA to perform corrective
actions to close wastewater lagoons and an area of buried drums between the North and South
Landfills, referred to as the Drum Remediation Area. The Corrective Action Plan called for
implementation of Interim Corrective Measures; completion of a RCRA Facility Investigation
(RFI); and a Corrective Measures Study. In 1988, when the TCEQ granted a Part B permit, the
state stipulated that the site conduct an RFI. The regulators agreed that one RFI could be
conducted to meet both requirements. The RFI Final Report was approved in June 1992.
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