Roy Thun is a Senior Environmental Specialist with GHD, Santa Clarita, California. Since 1987, Roy has built his expertise as an accomplished environmental portfolio manager and complex site strategy expert working in both environmental consulting and a Fortune 100 energy company. His expertise includes developing integrated site strategies and closure options for complex sites, CERCLA, stakeholder engagement, multi-party site coordination, consent decree negotiations, application of institutional controls, NRD negotiations, and independent review. Roy co-leads GHD's complex site strategy reviews, helping clients find cost-effective, reasonable & attainable remedial objectives and timelines for their sites. Roy is the Program Advisor for ITRC's TPH Risk Evaluation at Petroleum Contaminated Sites and current member of the ITRC PFAS team. He previously participated on ITRC's Long-Term Contaminant Management Using Institutional Controls team. Roy is also a contributor to several ASTM environmental liability standards. Roy earned a bachelor's of science degree in geology from California State University Northridge in 1988 and a master's in business administration (MBA) from Pepperdine University in Los Angeles, California in 1995. Roy is a Professional Geologist, ISI Envision Sustainability Professional (ENV. SP), and Los Angeles County Metro Sustainability Council Member.