As a consultant, Rehan works with clients and their advocates to develop effective solutions to complex environmental restoration challenges and secure approval from regulatory agencies for a wide range of public and private sector projects. His clients include insurance and liability holding entities; residential and commercial development companies; academic institutions; construction, architectural, and project management companies; metal recycling operations; petroleum companies; and law firms.
Clients depend upon Rehan's in-depth understanding of U.S. EPA and Cal-EPA permitting regulations, including the Resource Conservation and Recovery Act (RCRA); the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) the Voluntary Clean-up Program; and the California Land Reuse and Revitalization Act.
He has extensive experience with assessment and management of subsurface vapor intrusion to indoor air, a new and developing environmental field in California and across the national. He advices attorneys, real estate developer, and private sector clients on vapor intrusion regulations, regulatory agency negotiations, assessment, and customized mitigation system design and optimization. He also is experienced in providing technical support to legal counsel related to stormwater cases and has advised clients in stormwater compliance, permit negotiations, and development of non-structural and structural best management practices (BMPs). Rehan has evaluated and provided detailed design of structural BMPs such as multi-media filtration systems; biofiltration swales; infiltration and detention basins; and porous and impermeable pavements.
To advance the state of the practice, Rehan has managed and led teams responsible for the design and implementation of chlorinated solvent and petroleum hydrocarbon remediation systems such as soil vapor extraction systems, dual phase extraction systems, air sparging systems, slurry walls, permeable reactive barriers, in situ and ex situ chemical oxidation, pump and treat systems, sub-slab depressurization systems, and various enhanced bioremediation technologies.