Wastewater Treatment Director
Dr. Viraj deSilva, PhD, PE, BCEE is the Wastewater Treatment Director at SCS Engineers. Dr. deSilva has conducted projects throughout the United States as well as in Japan, France, Australia, Ukraine, Venezuela, Guam, India, Sri Lanka, Korea, Qatar, Jordan, Kuwait, UAE, and Iraq. He has 30 years of experience in the evaluation, sizing, and design of treatment processes for water, wastewater, leachate, and solids handling facilities. He leads the PFAS group at SCS and serves on several national level PFAS technical committees.
PFAS Management and Treatment
There has been a great deal of attention during the last few years on the chemical class called per-and poly-fluoroalkyl substances (PFAS). The most recent focus has been on the long chain PFOS (perfluorooctane sulfonate) and PFOA (perfluorooctanoic acid) PFAS compounds that are non-biodegradable in the environment and are subject to bioaccumulation in humans, animals, and plants. Since the 1950s, PFAS compounds have been used to make household and commercial products that resist heat and chemical reactions and repel oil, stains, grease, and water, such as nonstick cookware, stain-resistant carpets and fabrics, water-repellent clothing, paper, cardboard food packaging, and fire-fighting foams. PFAS shows up in the leachate of landfills that accept disposal of these consumer products. With the EPA positioned to take serious action on PFAS in late 2019, regulators in many states have already begun implementing measures of their own while state and federal courts are beginning to address legal issues surrounding this emerging contaminant. These changes mean new potential liabilities and consequences for organizations that manufacture, use, or sell PFAS or PFAS-containing products, and the time to take action to protect your operations is now. A number of established leachate treatment options to remove PFAS are available.
The presentation will include the findings of several PFAS studies conducted in over 100 North American landfills, including:
• 2019 Michigan state-wide study of landfill leachate PFOA and PFOS (NTH)
• 2019 Florida landfill leachate PFAS investigation study (Solo-Gabriele et al.)
• 2017 US landfill study for PFAS (Lang et al.) • 2012 Canadian landfill study for PFAS (Li et al.)
A number of established treatment options to remove PFAS from landfill leachate are available, including activated carbon, ion exchange or high-pressure membrane systems. On-site treatment options, including the management of reject streams where applicable, will be presented.
Body goes here