The Interior Department said last week it has formed a task force to oversee enforcement of its controversial irrigation water rules, but the move was quickly denounced as meaningless by a House subcommittee chairman.

James W. Ziglar, assistant secretary for water and science, said in a prepared statement that the task force's first job will be to set up audit procedures to ensure that only qualified farms receive subsidized water from the Bureau of Reclamation.

The rules, promulgated in April, were required under the 1982 Reclamation Reform Act, which congressional sponsors said was intended to force farms larger than 960 acres to pay full cost for bureau-delivered water.

The rules have come under sharp criticism from a principal author of the 1982 law, Rep. George Miller (D-Calif.), who said they contain loopholes that will allow giant corporate farms to continue to buy water at subsidized rates intended for smaller family farms.

Miller, chairman of the Interior water and power resources subcommittee, said the task force is "a public-relations ploy designed to create an illusion of interest" in enforcing the law's acreage limitations.

"This action is meaningless," Miller said in a statement. "It is designed to monitor compliance with regulations which are themselves fundamentally flawed.

Miller and Reps. Tony Coelho (D-Calif.), Vic Fazio (D-Calif.), and Morris K. Udall (D-Ariz.), won House approval recently of legislation to overturn the regulations. Their bill is pending in the Senate Appropriations Committee.