2020 Organization

Walter Simpson president


Walter Simpson is the Manager of Safety, Training, and Professional Development for The North American Coal Corporation in their corporate office in Dallas, TX.  With a solid background in organizational leadership, Walter has focused his career the development and training of safety initiatives.  He is skilled in design and implementation of: 1) Human Resources policy and procedures; 2) behavioral safety initiatives; 3) site specific and company-wide leadership development; and 4) effective communications.  He received his undergraduate degree from Troy University in Alabama and his Master’s in Psychology from Walden University in Minnesota. He holds certifications from the Society for Human Resources Management and the International Society of Mine Safety Professionals.  



Sunni Christon, is the HR Generalist for Martin Marietta’s Hunter Cement Plant, was hired at TXI in February 1998.  During her 19+ years of service at Hunter, Sunni has focused on relationship building among the employees at Hunter, the local communities, MSHA/the Department of Labor, and the local and national mining industry. As an integral part of her responsibilities, Sunni co-chairs the interactive Annual Training and trains new hires in safety and orientation.   She has facilitated and/or produced departmental safety meetings with a humorous twist.  


Suzy is the Safety Training, Compliance and HR coordinator for OCC Civil & Mechanical, LLC., a heavy industrial servicing & civil contractor.  She has over 6 years in the industry.  This is her first year serving on the conference committee.  With an extensive background in compliance.  From the start-up of a new company’s safety program, assisting with the over-all operations, conducting safety training and orientation for new hires, annual refresher safety training for all OCC employees, while maintaining compliance in all aspects of the company business.  When she’s not working you can find her enjoying life at a baseball tournament or on the lake with her husband, 4 kids and 2 grandchildren.

Dennis Johnson
James Pitre


30+ years of experience in mine safety and health. 2 years as a member of the planning committee for the Conference. Full-time Safety Coordinator for Dolese Bros. Co., an industry leader in crushed stone, sand, and ready-mixed concrete production with numerous locations throughout Oklahoma and Louisiana.


32 years experience in mine safety and health, 10 years as a member of the planning committee for the Conference. Full-time Safety Compliance Manager for United States Lime and Minerals overseeing processing plants throughout the South Central US.


30+ years in Mine Safety & Health, working for the safest coal mining company in America – North American Coal Corporation. Served voluntarily for three years on the Conference Association Planning Committee. Full-time Safety & Human Resources Coordinator for North American Coal – Caddo Creek Resources (the Marshall Mine) located south of Marshall, Texas. James enjoys spending time with his wife Lorrie, children and eight grandchildren.

Monty Tolbert
Troy Robertson


Currently EHS Coordinator for U.S. Silica Co. Mill Creek, Oklahoma Plants. Serves as the JA Holmes President for the South Central Oklahoma Council and has been a member of the SCJMSHC Planning committee since 2012. 42+ years mining experience in Industrial Sand and Crushed Stone. 37 years experience in Mine Safety 7 Health. Married and has 6 Children and 10 Grandchildren. Enjoys outdoor activities & family.


Operations Manager, Redstone Construction Group, Arkansas18 years experience in Construction Health and Safety and 5 years in Mine Safety and Health. Full time Director of Operations for Little Rock Quarries, Redstone Construction and Asphalt Products in Little Rock, Arkansas. Served 2 years as president for the JA Holms Safety Association for Arkansas. I have been a member of the SCJMSHC planning committee for 3 years. US Air Force veteran.


Christine Lemanski is the current Regional Safety and Health Manager for Lhoist in Texas.  She has supported various committees for the SCJMSHC Conference since 2015.  Christine has 10 years of mining experience, primarily in Health and Safety.  Outside of mining, Christine enjoys spending time traveling internationally, spending time with her family and most importantly seeking adventures for herself and “Peanut” her black lab.


Kayla Jo Dixon is Director of Safety for SamSand, LLC. She has been in the Mine Safety field for over 7 years. She has served on the SCJMHS Planning committee since 2014. She also serves on the Arkansas Mine Safety and Health Conference planning committee. Kayla Jo and her husband, Mitch, reside in Center Ridge, AR. They have 3 children. Kayla Jo loves to cook, listen to audio books, and always ceases an opportunity to cut up and laugh. 


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