(UPDATED at 10 a.m. local time Thursday with new data from National Hurricane Center)
By Ben DuBose
HOUSTON -- The remains of Hurricane Isaac continued to drench much of Louisiana on Thursday morning, bringing high winds and flooding to a region loaded with downstream infrastructure.
Isaac, which weakened to a tropical storm as it traveled inland through the state, made its final landfall early Wednesday near Port Fourchon, Louisiana, as a Category 1 hurricane with winds of 80 miles/hour .
However, Isaac's eye remained near the Gulf of Mexico and southern Louisiana marshes for several additional hours on Wednesday. As a result, the initial weakening process was very gradual, according to the National Hurricane Center (NHC).
Complicating matters further, Isaac moved at a crawl-like pace. For much of Wednesday, Isaac traveled at just 6 miles/hour, as opposed to a usual speed of 15-to-20 miles/hour for most storms.
The sluggish speed battered the New Orleans and Baton Rouge metropolitan areas, where conditions began deteriorating on Tuesday. Those regions were pounded by Isaacs eastern and northern eye walls, respectively notoriously the roughest parts of a storm.
Near 80% of the New Orleans area is without power, according to news reports, and localized areas received up to two feet (24 inches) of rainfall.
Refining market effects
Those conditions wreaked havoc on the numerous hydrocarbon processing industry (HPI) facilities in coastal Louisiana.
As of Thursday, five refineries in Isaacs path said they are shut down. Those sites have a combined output of 936,500 bpd, representing 12% of total Gulf Coast refining capacity, according to the Department of Energy (DoE).
The five Louisiana refineries to shut down include the Phillips 66 Alliance refinery in Belle Chasse (247,000 bpd), which on Wednesday reported that it had lost power entirely.
Other shut refineries are Valero at Norco (205,000 bpd), Motiva at Convent (235,000 bpd), Placid Refining in Port Allen (57,000 bpd) and the ExxonMobil/PdVSA joint venture in Chalmette (189,000 bpd).
Meanwhile, rates are reduced at Marathon Petroleums Garyville refinery (490,000 bpd), Motiva at Norco (233,500 bpd) and for ExxonMobil at its massive Baton Rouge complex (502,500 bpd).
The Environmental Protection Agency on Wednesday waived its clean gasoline requirements for 14 parishes in Louisiana, citing extreme and unusual supply circumstances
On the petrochemical side, major ethylene units believed to be down include Dow Chemical at Taft (610,000 tpy), ExxonMobil Chemical in Baton Rouge (1 million tpy), and the Williams/SABIC cracker in Geismar (612,000 tpy), according to consulting firm IHS Chemical.
Dow has derivative plants in Taft for ethylene oxide, monoethylene glycol and polyethylene that are also believed to be down, IHS Chemical reports.
ExxonMobil in Baton Rouge has also shut down its polyethylene, refinery-grade propylene and butadiene units.
Other significant petrochemical units reported to be down include the butadiene plant of Shell Chemical in Norco and both benzene units at the Phillips 66 Alliance site.
Gas processing, logistics closures
Enterprise Products said it has shut down all of its gas processing plants in south Louisiana, strategically located near offshore oil and gas infrastructure.
Due to storm shut-ins, there is very little output to process. As of Wednesday, 95% of Gulf of Mexico oil production and 72% of natural gas production was shut, the DoE reported. At least 505 Gulf platforms (85%) and 50 rigs (66%) are evacuated.
That, in turn, has led to declarations of force majeure for several major US pipeline systems, owing to production shut-ins.
The 1.2 million bpd Capline pipeline, which transports crude to refineries in the US Midwest, was shut down late Monday.
The production numbers could improve as soon as Friday, when Isaac is projected to be well inland and largely disintegrated. That should allow companies to begin re-staffing Gulf rigs and platforms.
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