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Chief Medical Officer

Dr. Billings serves as Associate Professor of Family and Community Medicine at Texas Tech University School of Medicine.  Medical students and family medicine residents routinely rotate with Dr. Billings, and he has been recognized with teaching awards from both Texas Tech University Health Sciences Center-Permian Basin and the University of Texas Medical Branch.  In 2015, the Texas Academy of Family Physicians honored Dr. Billings with the 2015 Exemplary Teaching Award for his work with precepting medical students.  In 2015, Dr. Billings also became director of the Texas Statewide Family Medicine Preceptorship Program. 
Dr. Billings currently serves as chief of staff of Big Bend Regional Medical Center, a critical access hospital, in Alpine, Texas.  Additionally, Dr. Billings serves as Co-President of the Presidio-Ojinaga Binational Health Council and as Medical Director for the City of Presidio Emergency Medical Services.




Dr. Katie Ray currently practices Family Medicine and Obstetrics in Marfa, Alpine and Presidio. In addition to a busy clinic practice, she delivers babies and cares for patients in the hospital. She has a special interest in women's health services, sports medicine and skin procedures. She heads a grant-funded program to provide free long-acting reversible contraception (IUDs and implants) to patients and training for residents about these devices. Additionally, she serves as Clinical Assistant Professor for medical students and residents with UTMB and Tech Tech Medical Schools.

John Ray, M.D.

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John Ray is from Pitner’s Junction, Texas and graduated high school in Troup. After getting a
degree in liberal arts from Northwestern State in Natchitoches, LA he worked as the farm
manager for Tyler ISD’s outdoor education facility for 6 years. He went to medical school at
UTMB in Galveston, and then completed residency at the University of Wisconsin in Madison.
During medical school, one of the key rotations that helped cement his decision to go into family
medicine was the experience he had as a student working in Alpine. He and his wife, the other
Dr. Ray, moved to Alpine in 2013 to start their practice. Inside of work, he enjoys obstetric care,
hospice care, and hands-on procedures (skin cancer removal, vasectomy, joint injections, and
working in the OR). Outside of work, Dr Ray loves welding, woodworking, and spending time
with his wife and kids. You might also catch him playing banjo with bands around town.



Dr. Edie Simmons is board certified in Internal Medicine and Nephrology, and practiced in Austin for 15 years before relocating to West TX to be closer to family.  She has expertise in the management of hypertension and kidney diseases, including caring for patients on dialysis and those with kidney transplants.  She was selected as a Top Doctor 2020 in Austin Monthly Magazine, and serves on the End-Stage Renal Disease Network of Texas.


She joined PCHS in Sept 2020, and practices Internal Medicine and Nephrology in Marfa, Presidio, and Alpine.  She has a special interest in kidney diseases and home dialysis.  She graduated magna cum laude from University of Mississippi Medical Center in 1997, where she also completed her Internal Medicine residency in 2001.  She completed her Nephrology fellowship training at Vanderbilt University in Nashville, TN in 2004.  She enjoys spending time with family, hiking, camping, gardening, and cooking.



I was born and raised outside San Diego, CA where I also obtained my Bachelor Of Science degree from Point Loma College in 1983. After briefly working in the pharmaceutical industry, I attended Jefferson Medical college in Philadelphia, PA, graduating in 1991. After an Internal Medicine residency at Virginia Commonwealth University in Richmond, VA. I joined the United States Air Force as a Flightsurgeon, separating as a Major. Moving to Austin in 1999, I was one of the founding members and executive staff for Hospital Internists of Austin where I practiced for 15 years. My wife Emely and I married in 2013 in Marathon, TX and afterwards moved to take a Chief of Outpatient Internal Medicine at San Juan Regional Medical Center, as well as Medical Director for the San Juan County Detention center in Farmington, NM. During the beginning of the Covid pandemic I took a position as an Internist in Saipan, CNMI for 1 year, prior to moving to Alpine TX where I hope to stay and practice for as long as the state will have me. Along the way I raised two children, played guitar in several bands, and travelled about everywhere I could think to travel. Im making up the rest of the story as I go.

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Presidio was my family’s hometown.  We eventually moved to Midland.  There I attended Odessa Junior College, later transferring to and graduating from the University of Texas at Austin with a degree in biology.  After graduation, I found employment in Dallas with the Food and Drug Administration.  There we monitored and tested food products for safety.  After five years there, I was accepted at Texas Tech Health Sciences Center medical school.  I graduated as an MD in 1983.  From there I began private practice in Dallas as a Board Certified Internal Medicine physician that was to last 34 years until my retirement in December 2020. I am pleased to be part of the PCHS team as a part time physician participating in the care of patients back in my home town and Marfa.

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William Mason, is a Certified Family Nurse Practitioner that was born and raised in Eagle Pass, Texas.  He graduated with his Bachelor of Science in Biology with a concentration in immunology and microbiology from the University of Texas at San Antonio.  He then obtained his Masters of Nursing Degree from Marquette University and completed his Family Nurse Practitioner certification at Angelo State University.  He is recently moved to Alpine and is eager to be serving the local communities of Alpine, Marfa, and Presidio.  He looks forward to taking care 0f patients of all ages and being part of the community.

Jacqueline Bow, LPC


Eleazar Cano, LPC

Alpine, Marfa, Presidio

Behavioral Health Counselors

Alpine Dental

Iris Korus, DDS


Tracy Cash

Dental Hygienist

Adriana Holguin

Dental Assistant

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