Most of the natural gas has stopped flowing from the well that blew wild earlier in the week. Authorities feel certain the gas became blocked by sand and sediment in the well located in about 155 feet of water 60-miles from Grand Isle Louisiana.
Ryan Tippets with the Joint Information Center monitoring the accident read a prepared statement:
"The fire has decreased the small flame fueled by residual gas at the top of the well. Bridging is a well condition where a small piece of sediment and sand flow into the well path and restrict and ultimately stop the flow. BSEE (Bureau of Safety and Environmental Enforcement) and the Coast Guard will continue overseeing response efforts until the event has come to a complete and safe resolution, which includes securing the well."
Don Van Nieuwenhuise directs the Petroleum Geoscience Programs at the UH. He says finding what caused the ignition is first on the list.
"Electric motor could do it. Almost anything could do it that has electricity involved. And when you have this sort of thing going on, you make sure that everything's turned off that has any kind of spark or significant heat or flame to avoid allowing that to happen."
He says rest assured, technology has greatly improved since drilling began in the Gulf waters, but:
"Occasionally things can go wrong, and of course there are a number of backup systems. One is the blowout preventer and I have no idea why that was not able to control it, but again I'd be looking at why that didn't work. It may have been a malfunction in the equipment, or it could have been a delay in initiating the sequence that shuts the sheer ramp."
Nieuwenhuise says a rig blowout he was involved in years ago had way more gas than the Hercules rig, but they were lucky to keep the gas cloud from igniting.
"You recall the Brenham pipeline when that exploded. If you have a small valley and you fill that up with natural gas and someone were to drive a car into it, that can be a serious issue. So, you want to keep people well away from any gas cloud and gas accumulation to avoid that ignition."
The accident on the Hercules platform happened when workers aboard the rig hit an unexpected pocket of gas while preparing the well for production.