An oil spill in the lower Chesapeake Bay last year cost $1.3 million and killed 31,000 waterfowl, making it the most devastating spill in Bay history, the U.S. General Accounting Office has reported.

The GAO told a congressional subcommittee recently that the spill caused by the sinking of a Steuart Transportation Co. barge that was being transported by Allied Towing Co. forced more than 250,000 gallons of oil onto the water.

That oil spill in February, 1976 was smaller than the 7.5 million gallons of oil let go by the Argo Merchant when it sank off Nantucket later last year.

But damage to the Bay area was more extensive because of waterfowl death and the beach and shore pollution in the Steuart Co. spill, the report said.

That spill at the mouth of the Potomac River near the Maryland-Virginia line caused shoreline pollution along a 20-mile stretch on the Eastern Shore of the lower Bay and a five-mile stretch on the western shore, according to the GAO.

Two clean-up companies employed about 100 workers using mainly pitchforks and shovels to remove about 110,000 gallons from the fouled areas on the Eastern Shore.

"The full extent of environmental impact on the wetlands of the Chesapeake Bay shore contaminated by oil is unknown," the report to Congress said.

The GAO report was compiled for a subcommittee headed by Rep. Leo J. Ryan (D-Calif.) that is investigating oil spills.

The report divides the $1.3 million cost of the spill between $608,540 in clean-up costs, 635,325 for dead waterfowl and $78,750 as the value of the oil lost.

Steuart Co. paid $39,916 and denied further responsibility, according to the GAO.

A Coast Guard study placed the primary blame on the "negligence" of a Steuart Co. tankerman who had failed to secure properly cargo hatches.