Tri-Valley Corporation Announces Commencement of New Drilling at Claflin

Tri-Valley Corporation (NYSE Amex:TIV) today announced that drilling has
begun on the first of six new vertical wells to develop proved
undeveloped ('PUD?) reserves at its Claflin oil project, located in the
Edison Oil Field near Bakersfield, California. The Company expects to
complete the drilling of all six wells to an approximate depth of 1,000
feet within the next three weeks. Following completion, the new wells
will receive their initial steam injection cycle and should be producing
first oil by June. An evaluation period of 60 to 90 days will follow to
analyze results before commencing the second drilling phase at Claflin.

'We are off to a successful start on a key 2011 initiative for the
Company, to increase oil production by converting a portion of our PUD
reserves into the proved, developed, and producing ('PDP?) category,?
said Maston N. Cunningham, President and CEO of Tri-Valley Corporation.
'Based upon our year-end independent reserve report, Claflin has over
two million barrels of PUD reserves in place. Our plan is to drill a
total of 22 new wells at Claflin during the year, including 13 vertical
wells and nine horizontal wells, and to install facility upgrades. If we
are successful, we expect Claflin to exit the year with gross daily
production of about 800 barrels of oil with an API gravity of 16 degrees
and anticipate a peak oil production rate of about 1,200 barrels per day
from the site in 2012. We also anticipate that additional PUD reserves
can be established as these existing locations are converted into the
PDP category.?

During 2010, the Company reactivated four of eight existing wells at
Claflin that had been drilled during the 1960′s in order to hold the
lease by production. Permitting for a 3-D seismic program of Claflin and
the adjoining Brea lease, which Tri-Valley also holds, is underway with
results from the seismic study anticipated by late May. The seismic data
will allow the Company to optimize the locations of its development
wells and provide better control during the drilling of horizontal wells
on the properties. Tri-Valley has a 100% working interest and an 87.5%
net revenue interest in Claflin.

The Company also announced that it has received notification from NYSE
Amex confirming that, based on its review of Tri-Valley Corporation′s
publicly available information, the Company has successfully resolved
its continued listing deficiency. As previously disclosed, the Company
raised sufficient capital to meet the NYSE Amex stockholders′ equity
requirement of $6 million, with total stockholders′ equity at December
31, 2010 of $6.2 million.

About Tri-Valley

Tri-Valley Corporation explores for and produces oil and natural gas in
California and has two exploration-stage gold properties 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

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
the expected timeline for well-drilling completion, first oil
production, installation of facility upgrades and seismic study results,
as well as the anticipated number of wells to be drilled, gross barrel
production and production rates, 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; imprecise estimates of oil reserves; drilling
hazards such as equipment failures, fires, explosions, blow-outs, and
pipe failure; shortages or delays in the delivery of drilling rigs and
other equipment; problems in delivery to market; adverse weather
conditions; compliance with governmental and regulatory requirements;
fluctuations in oil prices; 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.

Tri-Valley Corporation

John Durbin, 661-864-0500

jdurbin@tri-valleycorp.com

or

EVC
Group, Inc.

Investor Contacts:

Doug Sherk or
Jenifer Kirtland, 415-896-6820

dsherk@evcgroup.com

jkirtland@evcgroup.com

Media
Contact:

Chris Gale, 646-201-5431

cgale@evcgroup.com