Colonial Pipeline gasoline spill in Shelby County

Aerial photo of two of the three mine water retention ponds at the site of a pipeline leak that spilled an estimated 250,000 gallons of gasoline in Shelby County, Ala. The retention pond on the right is where the gasoline has been contained. (Courtesy Colonial Pipeline)

The gasoline pipeline leak that was reported last week near Helena spilled approximately 6,000 barrels -- or 252,000 gallons -- of gasoline in a remote area of Shelby County, the pipeline owner said today.

Colonial Pipeline, an Alpharetta, Ga.-based company that operates 5,500 miles of pipeline from Houston to the New York harbor, announced the volume estimate Wednesday on its spill response web site.

"There has been no threat to public health or safety, and the safety of the responders remains the top concern," reads the latest update. "Measures to protect the environment have been in place since the early hours of the response." UPDATE: Gasoline pipeline may still be leaking in Shelby County

The company said approximately 500 employees and contractors are currently working on the response.

The U.S. Environmental Protection Agency, as well as state and local authorities, are involved and a joint incident command has been set up at the scene. A large area around the spill has been cordoned off for public safety, due to potentially hazardous gasoline fumes, and precautions are being taken for response workers.

A local shooting range was closed as a precaution, and airspace over the incident site has been restricted. Air monitors are in place and water samples are being taken to ensure the spilled gasoline is not reaching the nearby Cahaba River.

Most of the spilled gasoline is contained in a mining retention pond, and workers are using skimmers to remove the gasoline. Underflow dams have also been constructed and boom installed to prevent the gas from reaching a dry creek bed that runs from the pond to Peel Creek.

The leak was first reported Friday, Sept. 9 by workers at a mining operation who detected a strong odor of gasoline near the intersection of County Road 91 (Coalmont Road) and Lindsey Road. The mine workers called Colonial Pipeline, which confirmed the leak.

Colonial Pipeline spokesman David York told AL.com Sunday that once the company confirmed the leak, two nearby pipelines were shut down. One of them was determined to be safe and restarted. The other, which was leaking, is being excavated for repairs.

York said the leak was in a remote area of the county, with the nearest residence being more than two miles away.

In addition to working with the EPA and other environmental agencies, Colonial Pipeline has collaborated with conservation group Cahaba Riverkeeper and Tri-State Bird and Rescue to minimize environmental impact.

Cahaba Riverkeeper David Butler called the company's "aggressive" response "refreshing" compared to how some companies deal with environmental spills.

"Every concern we've had, they've addressed with really no pushback," Butler said. "As bad as any situation like this is, all you can really ask is that they be responsible and accountable and I certainly haven't found any fault in their response so far.

"I think they're genuinely concerned about protecting the river."