Bulk gasoline storage tanks operated by major oil companies in the Washington area have received 5 percent more gas this year than in the same period last year, but do "not appear to be brimming or overflowing," according to a U.S. Department of Energy audit released yesterday.

The audit did not explain why gasoline sent into the tanks by pipeline are up 5 percent when gas supplies at area service stations have been curtailed by as much as 25 or 30 percent.

U.S. Rep. Herbert E. Harris II (D-Va.), who requested the audit, said yesterday that he is "totally unsatisfied with it.

"Even though (the Energy Department auditors) took 10 days, their audit is a lick and a promise. I wanted a real, on-the-ground audit of both volume coming through the pipelines (to the Washington area) and storage."

Harris made his request after The Washington Post, quoting sources with firsthand knowledge of operations at the two Fairfax County bulk storage "tank farms" serving the Washington area, reported that many of the multimillion-gallon tanks were so full that new shipments were being turned away.

"Frequently, on days when major (pipeline) deliveries are received, individual storage tanks may be filled or at near capacity," the audit report said.

But the report did not elaborate on this. It did not fully deal with the assertion by the Post's sources that the tanks are so much fuller than normal that pipeline shipments were being refused for lack of space.

The tanks receive 90 percent of the area's gasoline supplies by pipeline from Gulf Coast refineries. Tank trucks then deliver the gasoline to service stations here.

The Post report said that after being refused here, some shipments of gasoline were being sent north to Philadelphia and New Jersey on one pipeline at a time when motorists here were waiting in gas lines.

The audit report - called a "current summary" of a continuing audit - said that on the average the huge tanks "appeared to be" 50 to 60 percent full. The report noted that gas levels in the tanks rise and fall as pipeline deliveries come in and then are depleted by the tank trucks.

The 5 percent storage tank supply increase noted in the audit does not seem to square with information supplied to The Post by an official of Colonial Pipeline Co., the larger of two pipelines that bring gasoline here, that deliveries to the Fairfax City bulk terminal increased by 10 to 14 percent during the first five months this year compared with last year.

W.L. Nicoll, manager of community relations for Colonial, told The Post that deliveries to the Fairfax City terminal this May were 17 percent higher than last May. The Energy Department audit said that increases in pipeline deliveries during March, April and May - if any - were small compared with last year.

The report does not explain the contradiction or provide delivery figures for Colonial. Colonial delivery figures are lumped in with figures for the other pipeline in the audit.