David Folkes is a Senior Principal Environmental Consultant based in Colorado with more than 40 years of experience in environmental and geotechnical consulting with special expertise and experience in several areas including vapor intrusion (VI) evaluation and mitigation and soil and groundwater investigation and remediation.
As a consultant, Dave has helped clients on more than 200 VI projects across North America and overseas, including sites in Europe, South America, Australia, and Southeast Asia. He has been extensively involved with development of the VI practice over the past 20 years, including training of regulators and consultants on use of the 2002 draft EPA VI guidance and assistance with guidance development and training in several states. He was co-chair of the VI evaluation work group that helped develop the ASTM E2600-2008 standard practice for evaluation of VI during real estate transactions. As a member of two Interstate Technology and Regulatory Council (ITRC) teams, Dave helped develop and provide training on ITRC's VI and Petroleum VI guidance.
Dave has also addressed soil and groundwater contamination at numerous sites across the country under RCRA, CERCLA, UST, Brownfields, Voluntary Cleanup and other regulatory programs, including impacts due to chlorinated solvents, metals, petroleum, nutrients, pesticides, PCBs and other compounds. Groundwater remedies evaluated and implemented under his management include hydraulic containment, in-situ bioremediation, in-situ chemical oxidation, soil vapor extraction, multi-phase extraction, and other technologies.
For petroleum clients, Dave has worked on numerous sites, including former and operating oil refineries and gas plants, distribution and blending facilities, exploration and production fields, and retail sites. Over the past several years he has helped the Wyoming DEQ oversee the investigation and cleanup of several major oil refinery and gas plant sites, including removal of piping and infrastructure, soil remediation, LNAPL recovery, groundwater remediation, and boundary containment systems to protect adjacent rivers.
Dave has also helped metals and mining companies address environmental impacts at sites across the U.S., including management of remedial investigations, feasibility studies, and remedial actions; forensic investigations of the source of metals and arsenic in surface soils; and other metals-related issues.
Dave has provided expert testimony in state and federal court on several groundwater, soil, and vapor intrusion matters, including class action and multi-party lawsuits.