ARCO Blowout; Mississippi River Delta, LA

Mississippi River Delta, LA | 1992-Dec-26

Initial Notification: At 0823, December 26, 1992, an ARCO oil rig blew out a mixture of South Louisiana crude oil, hydrogen sulfide, and natural gas at South Pass, Block 60, Mississippi River Delta, LA. The blowout was reported to the USCG office by an ARCO employee. At 0900 a USCG overflight located the rig and reported that the release of natural gas, hydrogen sulfide, and a condensate of crude oil was ongoing and a boat on the upwind side of the rig was applying water to the diverter to cool it down. ARCO personnel on a rig less than one mile northeast of the blowout were prepared to evacuate in case of a wind shift. The slick tended to the southwest (approximately 220?). It was reported to be one to one and a half mile long and two to three hundred yards wide consisting mostly of a condensate. Rainbow and lighter sheen extended from one and a half to nine and a half miles from the rig. The smell of hydrogen sulfide was detected up to ten miles downwind. The amount of oil in the water appeared to be minimal. An exclusion zone was established within a ten-mile radius of the well because of the hydrogen sulfide gas threat. The well was capped on December 28, 1992, without significant impact. USCG district 8. Keyword: none.