The Energy Department's inspector general says his budget and staff are so inadequate that expenditures of "hundreds of millions of dollars" in the government's largest civilian procurement program are going unaudited.

Inspector General James R. Richards made the complaint internally when he sought $17.8 million last year for fiscal 1984. The Office of Management and Budget slashed this to $7.9 million, but raised it on appeal to $8.9 million.

Richards continued to protest, arguing that $10.9 million was "the minimum" needed and that the DOE was particularly "vulnerable to fraud, waste, and abuse due to the recent major shifts" of personnel as the Reagan administration has tried to abolish the department. But he failed to get additional funds.

Rep. Mike Synar (D-Okla.), chairman of the House Government Operations subcommittee that obtained the documents, has written Energy Secretary Donald P. Hodel expressing concern that the problems were not brought to Congress' attention.

Richards said the auditing of billions of dollars spent on creating the Strategic Petroleum Reserve has been "grossly inadequate," and said his office could not begin to audit expenditures on the nation's largest synthetic fuels project, the $2 billion Great Plains coal gasification plant.

Moreover, Richards complained that his office had only 10 investigators to monitor all of the DOE's facilities around the country. Major government installations--like the Savannah River Plant, which produces all the plutonium and tritium for the nation's nuclear weapons--"do not have any investigators," he said.

He also said his office had identified 54 major technical programs, ranging in size from $50 million to $2.7 billion, that should be inspected, and that at the initial level proposed by the OMB "our inspections staff can review just under one third" of them.

Richards said the Energy Department has more than 8,800 contracts and 8,300 grants totaling $16.6 billion waiting to be audited before they can be closed out. He cited as an example of a critical case the Elk Hills Naval Petroleum Reserve in California, for which he said $400 million in costs dating back to fiscal 1977 are awaiting an audit.