Ernest J. Guadiana


Bar Admissions

State of California

State of Connecticut

State of New York


J.D., Emory University School of Law

B.A., Boston College, Mathematics and Psychology

Ernest Guadiana has extensive knowledge of environmental, energy, and land use law. He regularly advises clients in navigating federal, state, and local regulations to obtain the necessary environmental and land use approvals to develop and construct projects. His work has put him before a number of regulatory agencies and jurisdictional boards and he has, at times, pursued administrative action when entitlements have been challenged, denied, or revoked. Mr. Guadiana also regularly advises clients of the impact of new federal and state environmental and land use laws to ensure his clients’ projects to continue to operate and remain compliant. With an in-depth understanding of the operations of oil, gas, and renewable energy producers, he has assisted an array of companies in governmental enforcement actions, disputes, and transactional matters.


Career Highlights


Seconded to a major oil company to support assets located within California, New Mexico, Ohio and Texas.

Defended an oil company’s Class II water injection permit in the first formal administrative action before the Division of Oil, Gas, and Geothermal Resources.

Assisted in the land use due diligence required for a Chinese entity to enter into a binding letter of intent to purchase a producing oilfield in Texas valued over US$600 million.

Assisted in preparing an enforceability opinion regarding mineral interests collateralizing a loan in excess of US$1 billion.

California counsel for an oil producer on US$750 million financing to fund acquisition activities.

Performed land use diligence to support a Canadian mining company in acquiring a copper mine valued at US$500 million.

Represented an oil company in navigating Coastal Commission permitting issues related to offshore drilling.

Advised on land use entitlements to aid the acquisition of a producing oilfield in California valued at over US$200 million.

Represented the unsecured creditors of a major oil company in challenging deeds of trust in order to unsecure assets.

Represented a major exploration and production company in navigating state and local permitting to drill a test well, which included environmental review under the California Environmental Quality Act and obtaining incidental take permits and drilling permits.

Negotiated an agreement for the development of Steam Assisted Gravity Drainage horizontal wells for an oil sands project in Oxnard, California.

Represented a mineral owner in negotiations for multiple oil and gas leases with a major oil company covering 10,000 acres in California.

Represented an oil and gas company in the acquisition of producing properties in seven states.

Represented a major oil company in negotiation of oil and gas leases and surface use agreements covering 50,000 acres in California.

Advised an oil company on the development of a shallow heavy oil diatomite project and its related pipeline and infrastructure construction.

Represented an oil and gas company in permitting a steam-injection oil recovery operation in Kern County.

Successfully petitioned the California Division of Oil, Gas, and Geothermal Resources to terminate a statutorily created unit.

Represented numerous developers in obtaining approvals from the California Division of Oil, Gas, and Geothermal Resources to develop properties with oil and gas wells.

Represented a renewable energy developer in a dispute regarding a solar project approved by the Public Utilities Commission.

Represented an oil company in a class action suit relating to payment of royalties on a townlot unit.

Successfully handled numerous quiet title actions to clear title to mineral rights.

Assisted in representation of an oil and gas operator in disputing the validity of a mineral joint venture.

Represented an oil company in an oil pipeline spill enforcement action brought by the City of Los Angeles.

Examined title and prepared numerous drillsite title opinions.


Land Use and Environmental

Successfully defended a writ of administrative mandamus through appeal that challenged a beach nourishment project on the basis that the project failed to comply with the California Environmental Quality Act.

Successfully negotiated the termination of a Williamson Act contract to allow the acquisition of an industrial park valued at US$120 million.

Drafted numerous memoranda advising on land use restrictions within California.

Obtained numerous discretionary approvals for commercial projects in Southern California, including conditional use permits and use variances.

Represented local agencies in their unfunded state mandate claims relating to municipal separate storm sewer system permits.

Represented a chemicals company in a land dispute regarding the placement of an oil and gas drill site within close proximity to its chemicals plant.

Represented a non-profit in developing a low-income housing project.

Represented a car wash facility in obtaining conditional use and building permits.

Represented a public agency in the drafting and enactment of a pipeline franchise ordinance.

Represented a local water agency in a complex litigation related to groundwater contamination.

Represented a local agency before the Regional Water Quality Control Board in defense of a notice of violation relating to underground storage tanks.

Advised iodine producer in determining its rights and obligations to pay royalty to the Bureau of Land Management.



2015-2020, Who’s Who Legal Directory, foremost practitioner of Energy law in California and the U.S.

2014-2020, Super Lawyers, Southern California Rising Star


Publications & Speaking

“What’s Underground Is Still Up For Grabs in Texas,” JD Supra, March 4, 2015

“Texas’ New (and Old) Take on Exculpatory Clauses,” Law360, April 28, 2014.

“Gas Regulations in 26 Jurisdictions Worldwide,” Getting the Deal Through, March 2013.