David Richardson is a Senior Engineer based in Minnesota with more than 30 years of experience managing and executing environmental assessment and engineering projects for private and public sector clients in the United States.
David has significant experience helping clients with multi-media investigation and remediation of coal combustion residuals (CCR), petroleum hydrocarbons, chlorinated solvents, and agricultural chemicals. He has designed and implemented a variety of groundwater extraction, multi-phase extraction, soil vapor extraction, vapor intrusion mitigation, air sparging, and injection systems using both vertical and horizontal wells. He has designed and implemented soil excavations, chemical oxidation treatments, in situ stabilization/solidifications for CCR and coal tar, and biological treatments for enhanced reductive dechlorination.
As a consultant, David has extensive experience assisting clients by evaluating and designing remedies for CCR impoundments that involve dewatering and capping and estimating seepage rates. He has used numerical models to evaluate groundwater impacts from seepage and develop remedial strategies that include large networks of vertical and horizontal pumping and injection wells. He has designed several horizontal pumping and injection wells over 1,000 feet long within and beneath CCR impoundments using directional drilling and one-pass trenching. Other CCR remedies include in situ flushing, monitored natural attenuation (MNA), and permeable reactive barriers (PRBs).
David helped demonstrate MNA for molybdenum in groundwater at an operating processing plant. Studies to support MNA included trend analyses, electrical resistivity, redox conditions, leaching studies, numerical modeling and stormwater runoff. He also designed a concrete cap at an operating fertilizer plant that serves as a rail and truck dry fertilizer unloading area. Cap construction ultimately led to lower nitrate concentrations in groundwater and site closure.
For agricultural chemical facilities and chemical production and manufacturing facilities, David has conducted hundreds of Phase I and Phase II ESAs. He has prepared and certified SPCC Plans for agricultural chemical facilities, bulk oil terminals, manufacturing facilities, and electrical substations.