Tri-Valley Corporation (NYSE Amex: TIV) today announced that independent geological consulting firm, Avalon Development Corporation of Fairbanks, Alaska, completed and submitted an NI 43-101 report which identified intrusive-related gold (IRG) mineralization on its Richardson project, located 115 kilometers (71.5 miles) southeast of Fairbanks. The Richardson project covers an area of approximately 46 square miles. Avalon’s report is based on updated geological, geochemical, and geophysical data. Based on Avalon’s findings, the Richardson project appears to contain at least three different types of intrusive related gold mineralization. Avalon has identified and recommends further sampling and evaluation of six prospective areas within the project. “The NI 43-101 report confirms earlier studies that indicated the potential for substantial gold deposits at the Richardson project,” said Maston N. Cunningham, President & CEO of Tri-Valley Corporation. “As part of the report, Avalon has recommended additional rock and soil sampling, mapping, and reconnaissance-scale prospecting to further identify the most prospective areas to be evaluated by drilling. We are currently evaluating the report’s recommendations; and, along with our efforts on our Alaska Shorty Creek project, we are seeking an experienced operational and financial partner to help us explore and develop the Richardson property.” The Richardson NI 43-101 report is available on the Company’s website at www.tri-valleycorp.com First Quarter 2011 Conference Call The Company also announced today that it will release its financial results for the first quarter ended March 31, 2011, after the close of market on Monday, May 9, 2011. The Company will host a conference call and webcast on Monday, May 9, 2011, at 4:30 p.m. Eastern/1:30 p.m. Pacific Time to discuss the first quarter financial results and current corporate developments. The dial-in number for the conference call is 877-941-0844. A taped replay of the conference call will also be available beginning approximately one hour after the call’s conclusion and will remain available for seven days. It can be accessed by dialing 800-406-7325 and passcode 4436246#. To access the live webcast of the call, visit Tri-Valley’s website at www.tri-valleycorp.com. An archived webcast will also be available at www.tri-valleycorp.com. Forward-looking Statements All statements contained in this press release that refer to future events or other non-historical matters are forward-looking statements. By way of example, statements contained in this press release related to future geologic studies, rock and soil sampling, mapping, and core hole drilling, and such other future events, business plans and objectives of management for future operations, are forward-looking statements. Although the Company does not make forward-looking statements unless it believes it has a reasonable basis for doing so, the Company cannot guarantee their accuracy. These statements are only predictions based on management’s expectations as of the date of this press release, and involve known and unknown risks, uncertainties and other factors, including: the Company’s ability to obtain additional funding or joint venture partners; availability of equipment and other resources, adverse weather conditions; compliance with governmental and regulatory requirements; and such other risks and factors that are discussed in the Company’s filings with the Securities and Exchange Commission from time to time, including under “Item 1A. 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, 2010. Except as required by law, the Company undertakes no obligation to update or revise publicly any of the forward-looking statements after the date of this press release to conform such statements to actual results or to reflect events or circumstances occurring after the date of this press release.