our team

Over 50 Years of Blasting Experience

Tom Greiwe


Tom Greiwe has been in the construction business for 30 years, 23 of which have been in the blasting industry. He has worked every aspect of the trade, from drilling and blasting to bidding and project managing. This background has resulted in an extensive knowledge of all facets of the job, from start to finish. His ability to manage and develop strategic site operations, allows the DemTech team to producea high-quality, safe, and efficient outcome on all our projects.

Although Tom’s experience primarily consists of mass and trench line blasting, his desire to tackle more challenging projects has led to a passion in demolition blasting. He holds licenses in several states and goes yearly for continuing education to stay up to date on the complex laws governing explosives. 

Tom is a life-long resident of Missouri, he has been married for 23 years and has two children in college. Tom and his family are very active in their community, church, and with charity organizations.

Shawn Leviere

Lead Blaster

Shawn has been in the drilling and blasting industry for over 8 years with a majority of the time working on major demolition with explosives sites.

He has become very knowledgeable on the use, handling and transportation of explosives. Often working at heights ranging from 50’ to 185’ above the ground or water.

His training has enabled him to perform blast designs of both rock drilling and blasting projects as well as man made demolition sites. He has been trained and performs explosives calculations pertaining to siesmic response related to the blast effects on neighboring structures including ground vibration and air blast.

Shawn has been very involved in the implementation of complex drilling and blasting designs, layouts and loading of varied explosive materials and initiation systems.

His on going training involves yearly explosives training classes, explosives handling and transportation, fall protection, man lift operations, heavy equipment safety, site safety procedures, OSHA and MSHA part 48 training, USACE safety training and explosives operations training.

Shawn is a conscientious job site Supervisor and Licensed Blaster that has been married for 13 years and has 5 children.

Scott Gustafson

Blasting Specialist and Estimator

In Scott’s 49 years in the explosives industry he has blasted over 1,000 bridge spans measuring over 43 miles in length, 37 power plants, 127 smoke stacks, numerous buildings/structures/silos, and nearly 1.5 million cubic yards of concrete.

He has been licensed and blasted in 43 States, the Virgin Islands and Korea.  He is well experienced in drilling and blast design of man made structures, rock excavation, trenching (to depths exceeding 60’), under water blasting, and mining.  Along with blast holes ranging from 1.5” to 12.125” in diameter and depth 6” to over 180’ deep. He is extremely knowledgeable in the use and application of all types of commercial and military explosives.

Among other things he has been or still is licensed or certified in:

  • RSO (Radiation Safety Officer)
  • Scuba diver
  • Private pilot

Scott has been married for 46 years to his high school sweetheart and has raised 2 boys and a girl.

 He has owned and operated 2 explosives related businesses:

  • Drilling and blasting company for 17 years specializing in the drilling and blasting of all types of rock for aggregate, mining, trenching, construction and coal.
  • Demolition with explosives company for 31 years performing explosive demolition of man made structures.