Workers have returned to most oil and gas production facilities in the Gulf of Mexico (GOM), but more than a quarter of natural gas production that was shut-in ahead of the arrival of Hurricane Isaac last week remained shuttered Wednesday, according to the Bureau of Safety Environmental Enforcement (BSEE).

Tennessee Gas Pipeline Co. LLC reported Wednesday morning it had found damage on one of its platforms. The pipeline declared a force majeure event for the Bay Marchand 5 Central Gathering System, and was assessing damage and developing a plan to return the platform to service. Meters shut in until further notice were: 01-0668 Grand Isle Block 47 Dehydration; 01-1105 Grand Isle Block 48 J; 01-2308 South Timbalier Block 23; and 01-2624 Bay Marchand Block 5. Tennessee did not say in its bulletin board posting how much gas was affected.

Based on data from offshore operator reports submitted as of 11:30 a.m. CDT Wednesday, BSEE estimated that about 25.71% (1.157 Bcf/d) of current daily natural gas production, and 49.33% (680,749 b/d) of daily oil output in the GOM was shut in. Those numbers were down significantly from the peak reached last Thursday, when BSEE reported 75.52% (3.264 Bcf/d) of gas production and 94.99% (1.311 million b/d) of oil production was shut in (see Daily GPI, Aug. 31), but were only marginal improvements from the 1.309 Bcf/d and 710,866 b/d BSEE reported on Tuesday.

Personnel remained evacuated Wednesday from 18 of the 596 manned production platforms, equivalent to 3.02% of the total platforms in the GOM. Personnel also remained evacuated from one of the 76 rigs in the GOM, BSEE said. Last Thursday those numbers peaked at 509 production platforms and 50 rigs evacuated.

Royal Dutch Shell plc said its manufacturing facilities at Norco, Convent and Geismar, LA, and Mobile, AL, were continuing the process of restarting their operations and were operating at either reduced or near-normal rates Wednesday. Anadarko Petroleum Corp. said it was continuing to ramp up production at all of its operated, producing facilities in the eastern and central GOM, including the natural gas Independence Hub.

Williams, whose Williams Partners LP operates a long list of gas processing and pipeline facilities along the Gulf Coast and in the GOM, said Wednesday morning that its onshore and offshore facilities in the eastern and central GOM "received no major damage during Hurricane Isaac." Williams' Mobile Bay gas processing plant was ready to begin processing gas "as soon as producer volumes increase and a third-party natural gas liquid pipeline becomes available," the company said, and the Geismar olefins production facility plans to resume operations this week following several days of maintenance unrelated to Isaac.

The onshore Larose gas processing plant and the Paradis fractionator have both returned to service, the Transcontinental Gas Pipe Line interstate system "is returning to normal operations as producers bring more production online," and the Devils Tower floating production system was flowing some gas production, Williams said.

The Environmental Protection Agency (EPA) has temporarily waived some federal clean gasoline requirements for gasoline sold and distributed in eight states impacted by Hurricane Isaac. The waiver allows available supplies of higher Reid Vapor Pressure "wintertime" gasoline to be used during the remainder of the high ozone period, which was scheduled to end Sept. 15.

"Due to a number of continuing refinery outages caused by Hurricane Isaac, and the slower-than-expected-pace of restarts of other Gulf-area refineries, EPA determined that there would not be an adequate supply of summertime gasoline for these states through Sept. 15," EPA said.

The National Hurricane Center (NHC) said Wednesday that a low pressure system located over the extreme north-central GOM about 25 miles southeast of Pensacola, FL, had a 40% chance of becoming a tropical cyclone by the end of the week. NHC was also tracking Leslie, which on Wednesday became the season's sixth hurricane as it continued to move north toward Bermuda, and Tropical Storm Michael, which was growing stronger as it moved slowly to the northeast more than 1,100 miles west-southwest of the Azores. Leslie and Michael are expected to remain far out in the Atlantic and are not forecast to approach North America, NHC said.

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