HIGHLAND BAYOU: APPROVED DESTRUCTION OF A MARSH

摘要

On December 18, 2004 the Texas General Land Office Oil Spill Prevention and Response Program was notified of a spill originating from an abandoned tank battery located in the marsh of Highland Bayou near Galveston, Texas. The discharge of 9460 gallons of crude oil into the bayou and adjacent marsh resulted from lack of maintenance to the tank battery. A vertical pipe attached to one of the tanks rusted through, allowing the tank to drain. The oil did not flow over the secondary containment, but seeped underneath it and spread through the marsh. This flow-path complicated the response by concentrating the spill in the subsurface, thereby impacting the roots system of the marsh plants, and rendering response techniques such as underflow dams, low water flushing, and in-situ burning either minimally effective or not viable. Aggressive tactics such as trenching and digging of holes in combination with massive water flushing were used to remove the oil. Short and long term consequences from these aggressive tactics were clearly evident in the trampling of the marsh grasses and changing of the local hydrology during clean-up operations. Initial trustee assessments determined the heaviest area impacted had died and was to be tilled. This provided a valuable learning opportunity for area responders and saved the surrounding acres of marsh.