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Peschong and Fodness Join HEI Adding Hydrogeology Services

Peschong and Fodness Join HEI Adding Hydrogeology Services


HEI has added hydrogeology as a new service sector with two new hires joining our Sioux Falls, SD, office: Brad Peschong, CPG, as Hydrologist III and Mark Fodness as Technician II, who together specialize in hydrogeology projects. 

Hydrogeology encompasses a variety of environmental consulting services, including geologic characterization of groundwater resources, hydrogeologic assessments for landfill siting and expansions, support for water supply development, and remediation for contaminated soil, soil vapor, and groundwater. 

An Experienced Pair

Brad is a Certified Professional Geologist (CPG) with nearly 40 years of experience. In addition to being a CPG, he is also a licensed Professional Geologist (PG) in Minnesota. Brad will lead HEI's new hydrogeology service sector for clients companywide. This will be especially valuable to HEI's existing waste management, environmental, water resources, and agribusiness sectors, providing clients with a wider range of services in house.

Mark has more than 23 years of diverse environmental consulting experience and specializes in field duties, including soil and groundwater sampling, bio-respiration monitoring, surfactant injection, and SVE/MPE system installation and operation and maintenance. 

Mark and Brad have worked together for more than two decades, creating a great team dynamic for this service sector. In fact, Brad and Mark already served on several teams with HEI to provide waste management services, so they will be familiar faces for many of our clients and staff.

"Brad and Mark's experience together is a great addition to HEI's talented team and naturally complements our expanding environmental service sector," states Jeff LeDoux, President/CEO. "Part of HEI's mission is to continue to adapt and evolve in our ever-changing industry. By adding Brad and Mark's skillsets to our team, we'll be able to provide clients with a complete suite of in-house services to help them with their projects from start to finish."

More About Brad

The South Dakota native grew up in Rapid City and Sioux Falls, SD, and attended South Dakota School of Mines and Technology (SDSM&T), where he earned his bachelor's degree in geological engineering. Since graduation, Brad has grown his expertise in hydrogeology, environmental investigations, and water supply development. In addition to his work experience, Brad completed graduate-level coursework in geological engineering and hydrogeology from SDSM&T as well as the University of California—Bakersfield. 

Brad stays current with federal environmental laws as well as environmental regulations and procedures for states throughout the Upper Great Plains. He has worked on countless projects related to Brownfield assessments; soil, soil vapor, and groundwater characterization; landfill permitting and monitoring; hydrogeology; and environmental site assessment. 

Fun Facts

  • Hobbies: Photography
  • Family: Married to wife, Laura, with two kids (Andrew and Emma)
  • Random Fact: He volunteers as a soccer referee for youth, high school, college and adult leagues 

Brad Peschong, CPG

More About Mark

Originally from Sioux Falls, Mark earned his associate degree in civil engineering from Southeast Technical Institute. Mark has performed hydrogeologic and vapor assessments to provide information regarding the extent and magnitude of soil, soil vapor, and groundwater contamination and remedial options at a wide range of environmental sites in Minnesota, South Dakota, North Dakota, Iowa, Michigan, Illinois, and Nebraska.  

Mark has performed aquifer pumping tests for regional water systems and municipalities. His expertise includes operation, maintenance, and sampling of soil vapor extraction; multiphase extraction and groundwater treatment systems; and all aspects of groundwater and soil sample acquisition and preservation.

Fun Facts

  • Hobbies: Hunting, fishing, racing, and snowmobiling
  • Family: Married to wife, Tracy, and have two daughters—Haley (13) and Riley (10)
  • Most Memorable Place He’s Visited: Hawaii 

Mark Fodness headshot