Rerouting Gulf of Mexico subsea systems, including an assist by Williams, is offering alternative transit for most of the natural gas and liquids carried by Destin Pipeline that were shut in by the Pascagoula Gas Plant (PGP) explosion late last month.

An explosion late last month shuttered the PGP plant in Mississippi (see Daily GPIJuly 5June 28). The Enterprise Products Partners LP straddle plant was processing 400 MMcf/d from the offshore before the incident, which remains under investigation. Destin began offering an alternate delivery option via its 24-inch diameter lateral on the Viosca Knoll Gathering System (VKGS), with deliveries averaging 350 MMcf/d-plus in the past week.

Deliveries from VKGS via Williams' Transcontinental Gas Pipeline (Transco) and the High Point Gas Transmission System (HPGT) are up since the explosion, according to Genscape Inc.

With Williams Field Services, Destin is reconfiguring its 24-inch diameter lateral near the Main Pass (MP) 260 platform, which would enable all Destin shippers to transport from VK 989, Mississippi Canyon 254, MP 281 and MP 283. Receipt points to Williams MP 261 JP platform would be carried onshore via Transco.

The Transco modification point, scheduled for service as soon as Wednesday, could offer "gradually" ramped up capacity of up to 210 MMcf/d, Destin said.

The hydrocarbon liquids limit of 16,000 bbl that is injected into Destin 36-inch diameter main line also has been lifted, but the pipeline is evaluating whether a new limitation may need to be implemented. Piping modification work is continuing at the MP 260 platform, and when completed, Destin expects to be able to offer transport services by July 24 via the Williams MP 261 JP lateral.

However, if the MP 261 JP is implemented, Destin said it may shut down its offshore production -- with the exception of the 24-inch diameter lateral. If the delivery point is not implemented by Thursday (July 14), the 24-inch diameter receipt points would need to be closed on Friday and Saturday (July 15-16).

Destin last week also was said to be investigating an option of reversing gas flows from the VK 900 point into HPGT. High Point's VK 289 location is an interconnect with VKGS. Since the PGP explosion, "we’ve seen a dramatic increase in receipts at High Point’s MP 289 VK Enterprise, up to 179 MMcf/d" as of last Sunday, Genscape analysts said. That would a total increase of 176 MMcf/d between June 28 and July 10.

Evening cycle nominations at the location showed 176 MMcf/d for Tuesday (July 12). Before the PGP outage, High Point's two-week average was 2.6 MMcf/d, and the three-month average was 1.8 MMcf/d, according to Genscape.

In a bulletin board posting last Friday, HPGT said it would not accept interruptible nominations at Targa's Venice meter 010217 in Louisiana because of the PGP outage until further notice.

"Our thinking is that by limiting gas entering the system at the Venice Processing Plant (mostly gas coming online from the western leg of High Point), this will free up more capacity along the mainline so that gas from the potential Destin reroute can make its way to the Enterprise Toca Processing Plant," Genscape said. From there, gas could be routed to the Southern Natural Gas or Tennessee Gas Pipeline systems.