RICHARD BACHMANN, as a former president and chief operating officer of Louisiana Land & Exploration (LL&E), knows a thing or two about the central Gulf of Mexico where the company was the biggest coastal wetlands landowner in the country before its acquisition by Burlington Resources. Ground zero for the worldwide offshore oil and gas industry, the shallow shelf of the central Gulf contains more than 500 oil and gas fields, 25 of which individually have produced more than 250 million barrels of oil equivalent.