Volunteer Board and Senior Staff

Healing Arizona Veterans Volunteer Board and Senior Staff

Board Members


Robert Sexton, M.D. 

Dr. Sexton has been a resident of Tucson since 1989 where he was in private practice until 2008.  At that point, he rejoined the military after an almost 38 year break. Once again a U.S. Soldier, he was deployed to Iraq and Afghanistan where he was a physician with Civil Affairs and a Field Surgeon attached to a forward deployed unit.  In 2009, during his Iraq deployment, he was diagnosed with Guillain-Barre Syndrome and was treated with plasmapheresis for the acute phase of the disease.  Four years later, he once again began experiencing severe symptoms similar to his prior GBS experience.  After neurological evaluation, he was then treated with HBOT, which resulted in a very significant clinical improvement — “a life changer.”  Dr. Sexton’s military, medical and personal experience with this therapy gives him a unique perspective as a strong advocate for HBOT.

Richard (Rick) Chimblo, Ph.D.

Richard (Rick) Chimblo, Ph.D.

Rick is a retired geophysicist and active Rotarian.  He has over 40 years of experience as a professional, a manager and an executive in the petroleum industry.  Since his retirement, Rick has served as President of Rotary Clubs in Texas and Arizona.  He has worked on various committees to develop and fund projects to assist the underprivileged children and families of Mozambique, Cameroon, Morocco, Mexico and Guatemala.  Rick has used his industry experience to develop financial models and budgets for non-profit groups and Rotary Clubs, successfully registering these entities as 501(c)(3) organizations with the IRS.

Don Siglin
Don Siglin, MBA

Don Siglin, MBA

Experienced executive with over 45 years of managerial leadership:

  • Eight years of work in the electronics industry as a Materials Manager
  • Twenty years as a plant manager in the Grain Bin sector of the Agricultural industry, final duty was VP of a division
  • Twenty years as a Sales Engineer for an environmental system for the oil and gas energy industry.
  • Mechanical Engineering Degree from Iowa State University MBA from University of Illinois.
  • ROTC Commissioned Officer in the Corps of Engineers.
  • Two years active duty with one year in Vietnam.
Mark Snow

Mark Snow

Marc is a retired Director from Raytheon Company with 32 years experience as a professional and manager in the Defense industry. During his career and in retirement, Marc has served as President of a Rotary club and is currently a Rotary Assistant Governor for the northwest Pima County region. Marc serves on the Board of the Rotary Vocational Fund of Arizona. As past development lead of various non-profit organizations, he brings years of non-profit fundraising and project management experience to the HAV mission.

Chandra Au Walker, MBA

Chandra Au Walker, MBA 

Chandra was born on an Army base in Nuremburg, Germany and raised in Hawai’i. She has four generations of military service in her family and her children aspire to be the fifth. Her spouse has been serving in the military for past 18 years. She has had nearly 15 years of Finance/Accounting experience and 5 years with military, non-profit organization.

Chandra is currently employed by Schwinn Hardware and has had different roles; Finance, Customer Service, Online marketing, Sales, and other activities. She graduated from Stevens-Henager College in 2014 with a Master’s in Business Administration with an emphasis/minor in Asset Management.

In Memoriam

Charles Spillar, BBA

Charles Spillar, BBA

*We lost our colleague, Charles, in October 2019, after his battle with health problems over several months. Read our tribute memorial here.*

Upon high school graduation, Charles joined the Army National Guard and served in G-2 (intelligence) during active duty and fulfilled an eight year total commitment. He has over 30 years in sales and financial background working with a Fortune 500 corporation dealing with every major banking institution in America. Charles received a NASD principal’s license, representative license from the Chicago Board of Trade and New York Mercantile exchange. In addition, he has 14 years experience in motion picture and television experience in production and screenwriting having written over 20 feature and television scripts as well as worked on over 100 movies and television shows. Charles has 28 years of visual arts experience with exhibitions numbering over 200 and write-ups in over 20 national and regional magazines.  

Senior Staff

Sa’ad J. Allawi, MBA

Sa’ad J. Allawi, MBA
Strategy and Operations Officer 

Mr. Allawi is the co-founder and Chairman of the Board of Performance Logic Inc. He has 35 years experience in consulting, 20 of those to healthcare organizations in various capacities. Prior to co-founding Performance Logic, Mr. Allawi led Nextera’s healthcare practice. Before that, he built and was the chairman of William Mercer’s healthcare provider practice. Prior to that, he built and was the director of APM’s Operations Improvement program. In addition to healthcare, Mr. Allawi worked in other industries. He was the Director of Business Development for AI industries and worked for McKinsey and Co., where he was a consultant to Fortune 100 companies and public sector organizations. He was an engineer with CA Parsons, the turbine generator manufacturers, and a section leader for MW Kellogg, petrochemical design engineers. He served on the Advisory Boards of a number of Healthcare Service and Technology companies and the Private Sector Development in Iraq for the CPA. He was a prior president of Oro Valley Rotary and Board member for Healing Arizona Veterans. He is an extensive public speaker on management and the Middle East.

Carol Henricks, M.D.

Carol Henricks, M.D. 
Medical Officer

Dr. Henricks has been a practicing neurologist in Tucson, Arizona, since 1999, focusing on coordinating all the best traditional and alternative therapies to optimize patient outcome. In 2004, she added the use of Hyperbaric Oxygen Therapy (HBOT) as an adjunctive neurological therapy for my patients as part of a complex neurological recovery program. Her private practice is dual: hyperbaric oxygen therapy and neurology. TBI is a focus of her work with our military veterans. Dr. Henricks is the Medical Director of Healing Arizona Veterans. As a regular writer for the blog, she discusses HBOT as an effective treatment for TBI, the misdiagnoses of PTSD that can lead to unnecessary medication, and the hard-won triumphs over TBI and PTSD. She believes it is a tremendous honor to work with our servicemen and women, helping them recover and to improve their quality of life.

Timothy Marshal, Ph. D.

Timothy Marshall, Ph. D.
Science Officer

Timothy M. Marshall, Ph.D. is a neuropharmacologist and nutritional biochemist with a passion for natural approaches to healing and nutrient therapeutics. Dr. Marshall earned his doctorate in Medical Pharmacology at the University of Arizona, College of Medicine with a minor in medicinal chemistry and toxicology, and has a Bachelor’s in biochemistry and a Master’s in organic chemistry. He is on the board of Healing Arizona Veterans, and is the author of the landmark publications, “The Next Generation in Brain Recovery and Neuroregeneration” (2017), and “Lithium as a Nutrient” (2015) in the Journal of American Physicians and Surgeons.

Website:  http://www.dr-marshall.com

Facebook:  https://www.facebook.com/DrTimothyMarshall

Instagram:  https://www.instagram.com/timothymarshallphd

Twitter:  https://twitter.com/DrTMarshall

Robin O’Bannon

Robin O’Bannon, Technical Sergeant, USAF, Retired
Veterans Outreach Officer

Robin served from 1987 to 2005 as an Enlisted member of America’s Air Force, retiring as a decorated, 100% service disabled Gulf War Veteran. Her career fields included Dental Technician and Manager, Leadership Instructor and Enlisted Accessions Recruiter. Robin has received two Associates degrees and an Occupational Instructor Certification from the Community College of the Air Force, a BBA in Training and Leadership and an MBA in Training and Development.

Bo Popovic

Bo Popovic
Grants Officer

Bo graduated in 1997, with a Masters in Public Administration with emphasis in Public Policy Development from California State University, East Bay. Discovering her personal and social need to work on the “greater good” projects, she worked on causes that provoked her inner need to act on where she received great joy.  Bo has held positions in development and fundraising for a variety of nonprofits and the educational sector for over a 25 year period. She also served on many boards, and as a member and/or volunteer for a number of associations and nonprofits throughout California, Oregon, and Arizona.

A few of her past positions held in Pima County were as the deputy director for the Pima County/Tucson Women’s Commission, the volunteer coordinator for MHC Healthcare, as the major gifts officer for El Rio Health and for the past year recruits patients, provides outreach and marketing for Eclipse Clinical Research as their Recruitment Specialist. She is now committed as a volunteer to Healing Arizona Veterans and their fund raising goals.