Tri-Valley Gets New Gas Production.

Business Editors

BAKERSFIELD, Calif.--(BUSINESS WIRE)--July 23, 2003

Tri-Valley Corporation (OTCBB:TRIL) is announcing a new zone discovery from reworking its Webb Tract No. 1 natural gas well west of Sacramento. The Company's subsidiary, Tri-Valley Oil & Gas Co., operator of the well, perforated a 12-foot section of the lower Capay formation and estimates a maximum open flow rate well in excess of 4 million cubic feet per day. Actual production rate will more likely be in the range of 1.2 million to 1.3 million cubic feet per day for optimum recovery, which is the current flow rate with 1,600 Psi flowing tubing pressure through a 12/64" choke.

The Company notes that another 50 feet of gas-saturated Capay Shale sits on top of the current producing section for future production potential. Little or no water accompanies the gas which Tri-Valley expects to test substantially above 1 million Btu per 1 million cubic feet.

Tri-Valley Corporation has a 40-year track record as a successful operator and is publicly traded over the counter on the electronic bulletin board under the symbol TRIL. The Company is also listed 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 include 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 March 31, 2003, and the annual report on Form 10-K for the year ended December 31, 2002.