PORTLAND – Former President Bush barred coastal gas and oil drilling, but environmentalists are gearing up to prevent his son’s administration from allowing new wells on Georges Bank, the rich fishing ground stretching 185 miles from Cape Cod to Nova Scotia.

Former President Clinton joined the elder President Bush in signing administrative orders barring coastal drilling through 2012, and Congress has approved one-year drilling moratoriums each year since 1982.

But coastal drilling “is back in play,” said Richard Charter, who has followed the issue for 25 years at Environmental Defense, a national advocacy group.

Vice President Dick Cheney’s national energy report released last month recommended that the secretaries of interior and commerce determine whether changes are needed to federal regulations related to coastal drilling.

And an Interior Department advisory committee recommended that an agency handling federal leases for drilling identify the top five coastal sites where drilling is now prohibited.

The report does not mention any specific sites, but Alaska and the Gulf of Mexico are two regions where offshore drilling historically is proposed.

Some lawmakers and environmental groups fear that Georges Bank also could prove to be an attractive target for two reasons.

California, which has a lot of political clout, opposes drilling along the Pacific coast. Also, Canadian drilling is under way near Sable Island off Nova Scotia, which is not far from Georges Bank, leading some to speculate there might be a rich trove of gas in that area.

At a House Resources Committee hearing Wednesday, two lawmakers asked Interior Secretary Gale Norton whether she would allow drilling on Georges Bank.

While Norton said she was not familiar with Georges Bank, she said President Bush “has been steadfast in saying he will honor the moratorium.”

House members, including Reps. Tom Allen and John Baldacci, both Democrats from Maine, sent Bush a letter Wednesday urging him to keep the moratorium.

New England’s five Republican senators, including Maine Sens. Olympia Snowe and Susan Collins, also sent a letter to Bush urging him not to repeal the moratorium because of potential damage to the fishing and tourism industries.

Drilling releases toxin-laced mud and wastewater, along with spilled oil. About 3 million gallons of oil spilled from offshore oil and gas wells in 73 incidents from 1980 to 1999, according to the House letter.

“We’ve got concerns,” said George Lapointe, Maine commissioner of marine resources.

The commercial fishing industry has worked hard in recent years to rebuild haddock and yellowtail fisheries in Georges Bank, said Bill Gerencer, board president of the Portland Fish Exchange.

“In principal, the Georges Bank has a unique geography that has been one of the best fishing grounds in the entire world,” he said.

Sen. Frank Murkowski, R-Alaska, said drilling at Sable Island, with the same environmental risks, already serves the region through a Canadian gas pipeline.

He has pushed for oil drilling in the Arctic National Wildlife Refuge, which the Maine delegation unanimously opposes.

“It amuses me that many of the folks in New England say they don’t want drilling, but they’re happy to buy their gas from Canada,” he said.