Tri-Valley Funds Another Exploration Prospect.

Business Editors

BAKERSFIELD,Calif.--(BUSINESS WIRE)--Sept. 15, 2003

Adding to its string of year-end exploratory prospects, Tri-Valley Corporation (OTCBB:TRIL) has completed the full $1,505,000 funding to drill a test well on a natural gas project located near prolific production areas west of Bakersfield, Calif., it was announced today by F. Lynn Blystone, president and chief executive officer.

Code named ERX, the natural gas project is scheduled to be drilled in the fourth quarter after drilling the Oil Lake Prospect southwest of Bakersfield around early November. Tri-Valley is now in the middle of drilling its Oil Creek prospect near Coalinga, Calif., and a previously drilled horizontal natural gas well near Delano, Calif., is in the final stages of clean up to test.

"All of these individual prospects are very big targets and together enable Tri-Valley to test 18 separate zones that are historically productive in the area. This multiplies our chances of commercial success on a large scale although it doesn't guarantee it," Blystone said.

He noted that Tri-Valley's program is based on 26 very large prospects to provide statistical probability of discovery success on a large scale. Any one of the targets could be a company maker on discovery success because of their potential size.

"Our job is to make discoveries that enable a multiple increase in our stock value as well as exceptionally reward our drilling partners that take the financial exploratory risk. We're now in position to go to bat several times, each time swinging for a home run. And we are continuing to build our drilling capital as investors seek a big program to access exploration opportunity in the huge, needy market of California," Blystone said.

The Company and its subsidiaries are headquartered in Bakersfield, Calif., a premier oil-producing province of the western hemisphere. Tri-Valley Corporation stock is publicly traded on the over-the-counter bulletin board under the symbol "TRIL.OB" in the United States and in Europe on the Berlin and Frankfurt Stock Exchanges under the symbol "TVC WKN 911919." Our company websites, which include all SEC filings, are www.tri-valleycorp.com and www.tri-valley.de.

This press release contains forward-looking statements that involve risks and uncertainties. Actual results, events and performance could vary materially from those contemplated by these forward-looking statements which includes such words and phrases as exploratory, wildcat, prospect, speculates, unproved, prospective, very large, expect, potential, etc. Among the factors that could cause actual results, events and performance to differ materially are risks and uncertainties discussed in the company's quarterly report on Form 10-Q for the quarter ended June 30, 2003, and the annual report on Form 10-K for the year ended December 31, 2002.