Tri-Valley Reports Increased Oxnard Oil Field Production in September

Tri-Valley Corporation (NYSE Amex:TIV) today announced that gross oil production during September from its Pleasant Valley oil sands project in Oxnard, California, averaged 324 barrels of oil per day as compared with 210 and 151 barrels of oil per day in August and July, respectively. Oil production at Pleasant Valley during September reached a peak rate of 600 barrels per day. September production reflects the results of additional cyclic steam stimulation and resolution of issues which had temporarily decreased production in the prior two months of the quarter. The Company’s reported production at Oxnard is net of diluent used to produce and process heavy oil for sale.

"September production improved at Pleasant Valley due to additional extended steam cycles completed during July and August on two horizontal wells on the Hunsucker Lease,” said Maston Cunningham, president and CEO of Tri-Valley Corporation. "July and August production at Pleasant Valley was lower than expected due to unavailability of production rigs for well repairs, and problems in processing cooler, higher viscosity crude oil pumped from wells nearing the end of their extended steam-oil production cycles. These issues have been resolved, and we expect continued momentum in oil production at Pleasant Valley.”

Given the cyclic nature of the Company’s steam injection operations at Pleasant Valley, monthly oil production will vary from month to month according to the actual number of days that each well is on production in a given month.

About Tri-Valley

Tri-Valley Corporation explores for and produces oil and natural gas in California, and has two exploration-stage gold properties and a high grade calcium carbonate quarry in Alaska. Tri-Valley is incorporated in Delaware and is publicly traded on the NYSE AMEX exchange under the symbol "TIV." Our company website, which includes all SEC filings, is www.tri-valleycorp.com.

Forward-looking Statements

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 "Item IA. Risk Factors" and "Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations" contained in the Company's Annual Report on Form 10-K for the year ended December 31, 2009 and in "Item 2. Management's Discussion and Analysis of Financial Condition and Results of Operations" as disclosed in the Company's Quarterly Report on Form 10Q for the most recent quarter ended June 30, 2010.