On Thursday afternoon August 1st, the Contractor at the Family Fare BP station on MLK near Taylor Street dug a hole for a footing for a new canopy, part of a renovation project to spruce up the gas station in order to give patrons more room and protection to the pumps. He installed a sump pump in the footing hole connected to a pipe leading to a Town storm drain, perhaps because rain was expected that night.
Then the crew went home for the night. A 2 – 3 inch rain began causing the pavement around the footing hole to cave in and puncture the high test gasoline tank. As the hole filled, the gasoline in the tank mixed with the rainwater, and the automatic pump pumped the mixture into the Town’s stormwater drain discharging into Crow Branch about 2 am. Crow Branch flows through a number of Chapel Hill neighborhoods, including Old Forest Creek and Coker Hill West and on downstream to Eastwood Lake. A policeman noticed the smell of gasoline at around 5 am and shut off the pump. The EPA made an estimate of pollutant concentrations of gasoline and ethanol – no official numbers yet. Unofficial numbers are 2400 gallons of gasoline of which 10% is ethanol was pumped into Booker Creek.
Though less dense than water, gas has a tendency to float which helped cleanup eforts. Some parts of gasoline evaporate quickly. However there is a dissolved fraction of gasoline with a small but still toxic percentage of compounds such as BTEX (benzene, toluene, ethyl-benzene and xylene) that mix and become dissolved in the water column. This fraction is extremely difficult to recover and treat and will be pervasive for some time to come. The EPA representative on site explained that an estimated 350 gallons of ethenol mixed into the water will be toxic to fish and wildlife.
Here is the picture story of the impressive emergency response. Emergency vehicles arrive at the lower end of the stream near Eastwood Lake at around 9 am Friday, August 2nd.
The first idea to make a dam out of sand did not work as the creek was running too fast to allow the sand to stay in place.
A baffle is put in place to capture some of the gasoline in case it arrives before dam is built.
Stone is ordered arriving in large trucks. The dam is begun as a large excavator lifts the stone into the creek.
The dam is in place. A large pipe underneath allows water below the surface to pass on down the creek channel. The baffles catch some of the gasoline floating on the surface and it is held back.
Zebra arrives to vacuum the gasoline caught by the baffles.
The BP station on MLK Jr Blvd, source of the gasoline release into Crow Branch and Booker Creek.
Gathered are Chapel Hill Fire Department personnel, supported by DENR and EPA experts, Orange County Emergency response, and Orange County Rescue squad who put in a day’s work executing a thoroughly professional response to this emergency. See Rhame letter from Region 4, EPA.
Remediation is still underway. The Contractor may be liable for remediation costs and well as other enforcement actions.