Not all of the oil emitted from Platform "B" was consumed by the fire. What oil did escape was largely recovered, and damage to the environment from the unrecovered portion was probably negligible. Here is a description of the various methods used to contain and recover the unburned fraction. Introduction Platform "B" in the Bay Marchand Block 2 field was Platform "B" in the Bay Marchand Block 2 field was set in July, 1969. To accelerate development two rigs were simultaneously drilling on the 12-pile, 36-well slot structure located in 55 ft of water. By Dec., 1970, a single-zone well and 21 dual-zone wells had been completed, one slot had been junked, and the rigs were drilling two additional wells. The completed wells produced about 17,500 bbl of oil and 40 MMcf of gas a day. All producing wells except B-21, a single-zone oil well, had Storm Chokes. For completion purposes, a waiver had been granted by the U. S. Geological Survey for that well. All operations were in full compliance with USGS regulations. The fire began at approximately 9:45 a.m. on Dec. 1, 1970. The platform was immediately evacuated. Sixty men were aboard, including four Shell employees. Four men died and 36 were hospitalized. Almost immediately two decisions were made: - to let the fire burn and kill the out-of-control wells with relief wells to minimize the amount of oil spilled on the water and - to use mobile diversionary systems combining booms and mechanical skimmers to recover oil not consumed by the fire. Equipment to achieve both goals was ordered within hours. This approach was more expensive and time-consuming than extinguishing the fire and capping the wells from the surface. However, it ensured minimal environmental damage from oil spillage. The first drilling rig arrived on Dec. 4. 1970. With the cooperation of other companies who let us use rigs under contract to them, we had five rigs in operation by Dec. 18. Two converted jack-up completion rigs equipped with high-pressure pumping and manifold equipment were brought in for the kill operations. Two spray barges with a combined water output of 14,000 gal/min were used to cool the structure and minimize deterioration of the platform and well tubing and casing. The first well with the largest fire, B-21, was killed on Dec. 30, 1970; this reduced the intensity of the fire by about 40 percent. On April 7, 1971, the tenth and final well killed with a relief well was extinguished The fire from the remaining out-of-control well, B-4, was put out with a water spray and the well was capped. Because of difficulties encountered in achieving communication with it through the relief well, B-4 was brought under control from the surface. Well B-4 was officially dead at 10:14 a.m., April 16, 1971, ending an ordeal that had lasted 136 days and 29 minutes. The pollution control aspects of the fire are described here. The general approach to the entire problem and the engineering considerations in the problem and the engineering considerations in the relief-well program are covered in other papers. Environment Platform "B" stands about 65 miles south of New Platform "B" stands about 65 miles south of New Orleans, in an area of considerable oil and gas activity, both offshore and in the bays. JPT P. 241
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