Staff Bios

Andy Peterson, P.E.  –    Founder and  President

After earning a B.S. in Petroleum Engineering from the Colorado School of Mines, Andy Peterson has gained over 30 years of experience in the oil field industry in various capacities throughout Colorado and Wyoming.   He founded Peterson Energy in Loveland, Colorado in 1989 and is a Registered Professional Engineer.

 Suzanne Peterson – Vice President

Suzanne comes to Peterson Energy Operating, Inc. from a long background in banking and finance. She joined her husband in the business in 1995 as Chief Financial Officer, overseeing the management and coordination of all fiscal activities, including accounting and reporting all oil and gas expenses and revenue to both interest owners and various governmental agencies. Suzanne assesses and performs ongoing risk management for the company and ensures stringent internal controls and reporting processes. Suzanne also maintains awareness and knowledge of changing regulatory requirements, financial reporting and tax compliance. Prior to joining the business, Suzanne led a 20 year career in Trust Investments, beginning with her training at Banker’s Trust Company in New York City, to her years as VP- Portfolio Manager at First Interstate Bank in Denver, and culminating in her nine year position as VP-Director of Trust Investments at First National Bank in Fort Collins, CO. Suzanne’s education includes graduating in the first co-ed class at Williams College (1975), a MBA with an emphasis on Finance at the University of Colorado-Denver (1982), and receiving her professional designation of Chartered Financial Analyst in 1984. Suzanne strongly believes in giving back to her community serving on various board and committee positions with the Community Foundation of Northern Colorado, United Way and Loveland Rotary.

Kellie Diffendaffer – Accounting Manager

Kellie joined Peterson Energy Operating, Inc. with a heavy background in accounting in many different fields including the beef industry, general contractor services, and pharmaceutical industry. Prior to Kellie joining Peterson, her 12 year stay in the pharmaceutical field found her responsible for the monthly, quarterly, and annual international financial reporting and budgeting. As accounting manager she was also responsible for the payroll and accounts payable processes. Kellie’s education includes an Associate’s Degree in Accounting from Aims Community College, and additional classes at Regis University and CSU Global in the accounting and business field. Currently at Peterson, Kellie processes accounts payable for numerous companies and normal monthly processes such as bank and ledger reconciliations, and preparation of financial reports. Other responsibilities include monthly, quarterly, and annual accounting and reporting to governmental agencies and interest owners of oil and gas revenues and expenses. Annual tax reporting and form preparation are completed to maintain compliance with county, state, and federal agencies. Kellie stays involved in the community with church volunteering and local school organizations.

funny man with mustacheRyan Dornbos – Petroleum Engineer

Ryan is the newest addition to Peterson Energy Operating, Inc. Ryan graduated from Colorado School of Mines in 2015 with a Bachelor’s Degree in Petroleum Engineering. He started his journey in the oil and gas industry in 2014 with a small operating company in Denver where he played a key role in company accounting, and organizing the sale of oil and gas assets. In his new position at Peterson, Ryan completes a multitude of tasks while learning what it takes to become a professional petroleum engineer. Ryan fills his free time with his second job at Blucore Shooting Center, woodworking, ping pong, hiking and fishing.

Cheyenne Carr – Accountant

Cheyenne earned an Associate’s Degree in Accounting from Front Range Community College in 2014 then continued her education at Regis University. She graduated in 2016 with a Bachelor of Science in Accounting. She started her career in a small public accounting firm where she worked closely with local small business owners. She had a wide range of duties which included processing payrolls, filing tax returns, completing reconciliations, general office administration and more. She resigned from that position in 2018 and accepted a Staff Accountant position at a company that provided funding for equipment. She was involved with month end closing, a high volume of reconciliations, securitization reporting for a large portfolio, financial reporting in compliance with GAAP and IFRS, fulfilling auditor’s requests and more. While working full-time she was also a full-time graduate student. She earned her Master of Science in Accounting from Regis University in 2019. Currently at Peterson, Cheyenne processes accounts payable for companies, completes bank reconciliations, prepares financial statements, completes monthly reporting to government agencies and more. Cheyenne spends her free time working on her side business, reading, weightlifting, and doing things with friends and family.

Rocky Peterson – Security

This ferocious watch dog keeps the office environment safe and secure.  Of course, if anyone has a treat, security can be briefly breached.   However, once the treat has been consumed, high level security is back in place immediately.