A.D. Koen
Gulf Coast News Editor
Hurricane Andrew's long term effect on Gulf of Mexico oil and gas operations likely won't be known until next year.
While damage assessments have moved beyond the emergency stage, many offshore service companies say reliable estimates of the extent of damage or cost of repairs still are unavailable.
The time needed to complete restorations won't be known conclusively until more organized surveys are complete.
Even then, many contractors say, gulf operators must decide how to handle damage at each location - whether to repair damaged structures or replace them by applying technology not available when many of the fields were developed. Some damaged installations will not be replaced or restored, and the production will be lost.
Minerals Management Service estimates that 850-900 MMcfd of gas and 50,000-90,000 b/d of oil production in the gulf remains shut in, all but about 100 MMcfd of gas production because of Andrew.
MMS Director Scott Sewell said damage to Gulf of Mexico oil and gas operations in Andrew's path was more extensive than first believed. But MMS officially estimates the long term effect will be small (OGJ, Sept. 28, p. 42).
Meantime, officials at the Weather Research Center (WRC), Houston, expect to be computing wind fields and maximum wave heights for the next 5 years, as oil and gas companies maneuver to fix the blame for hurricane damage.
RESTORING PRODUCTION
An official of Oceaneering International Inc., Houston, said offshore contractors have worked through most preliminary damage assessments and completed emergency repairs.
"We now expect to move into more planned and coordinated inspection and repair work, as required by the MMS," he said.
MMS Sept. 17 directed gulf operators to conduct Level II surveys of offshore oil and gas structures in an 85 mile corridor tracing Andrew's path.
Oceaneering said the time needed to complete repairs won't be known until gulf operators make a variety of decisions. The effect on gulf oil and gas production will depend on those choices.
"Today we have a variety of technological means not available when many of the damaged platforms were installed," Oceaneering said. "Operators might decide to use subsea completions or mobile production systems to restore production in larger fields rather than building new platforms.
"Many operators could choose to abandon smaller, older wells. A lot of wells that won't be repaired weren't producing too much, anyway."
Oceaneering has signed more than 40 contracts because of damage caused by Hurricane Andrew, many involving inspections of multiple structures.
More than 25 companies have hired Oceaneering to assess or repair storm related damage. Company officials estimate inspections account for about 75% of the work, with the remainder consisting of salvage operations and pipeline repairs.
MMS early in September estimated that Andrew had forced gulf operators to temporarily shut in 2.55-2.75 bcfd of gas and 240,00-270,000 b/d of oil (OGJ, Sept. 14, p. 38).
BACKLOG OF WORK
John E. Chance & Associates Inc. (JECA), Lafayette, La., estimates 45-60 days will be needed to work off the backlog of work resulting from Andrew.
"How or how quickly oil companies will act on damage assessments is hard to say," a JECA official said. "There might be some marginal fields where they decide to pick up the garbage that's left and leave."
Already in a seasonal August-November activity upswing, JECA's business picked up about 35% because of Andrew. "In the first 48 hr after the storm hit, we received more than 50 calls," the company said.
Many calls right after the storm involved helping offshore pipeline operators locate lines in mud slide areas.
"Large storms like Andrew cause mud flows to start moving again down inclines, and that severed several pipelines," JECA said.
After an initial rush of activity lasting about 2 weeks, calls for Andrew related work slowed.
"Now we've come back and we're starting to do some reconstruction and salvage, changing focus from identifying to rectifying some of the problems," JECA said.
One of the gulf's largest offshore service companies, JECA is big enough to field 35 crews in a matter of hours. The company stretched its normal capabilities by canceling all vacations, sending office personnel to help in the field, and borrowing workers from other divisions.
STATUS OF SARATOGA
Zapata Corp., Houston, expects in November to return the Saratoga semisubmersible drilling rig to Mississippi Canyon Block 705 where it will resume work on a wildcat it was drilling for Shell Offshore Inc. before Andrew stuck.
The hurricane passed over Saratoga's location, where the rig had been prepared for the storm and evacuated, severing the mooring system. After the storm, Saratoga was found on Grand Isle Block 47, about 50 miles from its former site (OGJ, Sept. 7, p. 24). Zapata estimated surface winds of 150-160 mph would be required to sever anchor lines.
Zapata has recovered all severed parts on the mooring system at the location, and some can be salvaged. Last week the company was awaiting delivery of parts for components that must be replaced.
Saratoga is equipped with an eight point mooring system, with each point consisting of a 40,000 lb anchor, 2,200 ft of 2 3/4 in. chain, and 4,600 ft of 2 3/4 in. wire rope.
The unit is in Galveston, Tex., for repairs.
FORENSIC METEOROLOGY
Because a lot of litigation is expected to place blame for damage inflicted by Hurricane Andrew, offshore operators and contractors are reluctant to discuss some details of their storm related activities.
"It's so important whether the storm damaged an installation or another company's equipment caused the damage," an offshore service company official said.
That is where WRC plays an important role, using the center's computer models to recreate wind fields and wave heights of storms. The models also can be used to track storms as they weaken over land.
A WRC official described Hurricane Andrew as a compact, symmetrical, well organized storm. Hurricane force winds, defined as sustained winds exceeding 75 mph, were confined to about a 50 mile radius around Andrew's eye. Tropical storm winds, sustained winds of 39 mph or more, extended outward about 150 miles from the center of the storm.
As Hurricane Andrew left South Florida and began moving across the gulf, WRC provided weather advisories every 6 hr to offshore contractors and operators. Some points received updates every 3 hr.
Data gathered by the National Oceanic & Atmospheric Administration showed Andrew's maximum sustained winds were 140 mph, with gusts reaching 160 mph. Those characteristics were enough to qualify the hurricane as a Category 4 storm.
Copyright 1992 Oil & Gas Journal. All Rights Reserved.
