FACTBOX: Oil releases from U.S. Strategic Petroleum Reserve

(Reuters) - The U.S. Department of Energy said on Thursday it will release crude from the nation's Strategic Petroleum Reserve if Tropical Storm Gustav causes severe supply disruption.

The SPR, the world's largest emergency oil stockpile, was created by the Congress after the 1973-74 Arab oil embargo. As of August 22, it holds 707.2 million barrels of crude oil in 62 underground salt caverns along the Texas and Louisiana coastline.

Only the president has the authority to release oil from the stockpile. In July, lawmakers pushed the White House to tap the SPR and release 70 million barrels, or 10 percent of its stockpile, into the market to help ease high gas prices.

Heavy opposition stopped a House bill in favor of the oil sale as Republicans protested that the reserve was meant to offset major oil supply disruptions and not to rein in soaring crude prices.

The U.S. government has released oil supplies from the SPR on many occasions to offset supply disruptions.

The following lists oil sales and loans made by the U.S. government from the SPR :

OIL SALES:

* 1985 Test Sale - 1.1 million barrels.

* 1990-91 Desert Shield/Storm sale - 21 million barrels. (4 million in August 1990 test sale; 17 million in January 1991 presidentially-ordered drawdown).

* 1996-97 Total nonemergency sales - 28.1 million barrels. (5.1 million in Weeks Island sale to pay for decommissioning of storage site and transfer of its oil; 12.8 million to reduce the federal budget deficit; 10.2 million to offset fiscal year 1997 appropriations).

* 2005 Hurricane Katrina sale - 11 million barrels.

OIL LOANS:

* April/May 1996 - Loaned 900,000 barrels of SPR crude to ARCO to resolve company's pipeline blockage problem.

* August 1998 - Exchanged 11 million barrels of lower quality Maya crude in SPR with PEMEX for 8.5 million of higher quality crude (more suitable for U.S. refineries)

* June 2000 - Loaned 500,000 barrels each to CITGO and Conoco, due to blockage of the ship channel that allowed incoming crude oil shipments to those refineries.

* July/August 2000 - Exchanged 2.8 million barrels of crude oil for first-year tank storage and stocks for 2 million barrel Northeast Home Heating Oil Reserve.