What Could Possibly Go Wrong During the Sediment Remediation
Bob Wyatt, Director of the Legacy Environmental Program, NW Natural
Co-Authors: Michael Crystal, Vice President of Operations, Sevenson Environmental Services, Inc., Ryan Barth and Kendra Skellenger, Anchor QEA, LLC
The former Portland Gas Manufacturing (PGM) plant, historically located on the banks of the Willamette River in downtown Portland, Oregon, produced manufactured gas between 1860 and 1913. Sediments adjacent to the former PGM plant, as well as areas disturbed by seawall construction, were contaminated with tar-like material, polycyclic aromatic hydrocarbons, and other contaminants of concern. The client assembled a Design-Build project team that worked with the State oversight (Oregon Department of Environmental Quality) to negotiate the Remediation Work, and the Sampling & Analysis Plans to ensure timely approvals so that each phase of the dredging and capping would be implemented with minimum delay. This Design-Build-State relationship was critical to successfully completing the project during the three month in-water work window. Extensive planning and treatability studies were performed to plan the remediation, which involved a combination of dredging, reactive capping with granular activated carbon, sand covers, and natural recovery. Dredging and capping of contaminated sediments intermixed with large building debris presented challenges for design and remedy implementation. The dredging was completed using a site-specific mobile moonpool silt curtain to protect water quality with additional silt curtains around the work area. The building demolition debris made capping specifications more difficult to meet. Sediments were remediated during the limited in-water construction season, under the oversight of the State using a combination of dredging, reactive capping with granular activated carbon, sand covers, and natural recovery. Through Adaptive Management during the sediment remediation, the following issues presented unique challenges to maintaining the project schedule and completion in one season: daily social justice protests in downtown Portland, vandalism, COVID-19, and wildfires that caused unworkable Air Quality Index levels for personnel. The most challenging issue was the inadvertent discovery of large quantities of live World War II munitions and explosives of concern (MEC), requiring extensive modifications to the operations to ensure the safety of the workers and the public using the immediately adjacent park and river.
Bob is the Director of the Legacy Environmental Program at NW Natural. He has 30 years of experience managing complex environmental liabilities, including EPA sediment Superfund Megasites, and has degrees in Geology, and Environmental Science and Land Resources. He started his career in the mid-1980s as an environmental consultant working on Superfund, RCRA, landfill and petroleum sites in New Jersey and surrounding states. In the late 1980s, he moved to North Carolina to become Vice President of a consulting firm, where he was principal in charge of projects nationwide. He moved to Oregon in 2000 where he began his utility career at NW Natural. For seventeen years, Bob was also the designated Project Coordinator on the EPA Order for the Remedial Investigation and Feasibility Study for the Portland Harbor Superfund Site.
Bob is the lead negotiator at high profile environmental projects with federal, tribal, and local government oversight and public stakeholder involvement, and has extensive communications experience with the media, congressional delegates, and community groups. He spent more than 15 years as chair of a multiparty PRP group consisting of governmental, public utility, petroleum and industrial organizations. He also provides support for litigation and public utility rate cases. Bob enjoys mediating complex technical issues, working collaboratively with stakeholders, and the process of building consensus.
Bob is a licensed Professional Geologist in Oregon, Washington and several other states.