EA Engineering, Science and Technology, Inc., PBC
Craig Kyhl, an Engineer located in EA Engineering, Science, and Technology, Inc., PBC’s Anchorage, Alaska office, has worked on the Moose Creek project - mitigating the health and environmental risks posed by perfluorinated compounds (PFCs) – since joining the firm. As a result, he has a developed knowledge of the unique issues and challenges associated with remediation of PFCs in the absence of definitive regulatory directives and given their resistance to typical environmental degradation processes. As the project is located in Fairbanks, Alaska, Craig has a solid understanding of what it takes to design, construct, and maintain remedial system operations, as well as to perform required sampling and analyses, within a sub-arctic climate and abbreviated field season. Equally important, Craig is now familiar with public outreach and stakeholder communication requirements as the Moose Creek project encompasses more than 150+ properties including residential, commercial and public buildings. Craig graduated from the University of Wyoming with a Bachelor of Science degree in Civil Engineering. He is registered as an Engineer-in-Training and certified under as OSHA’s 40-hour Hazardous Waste Operations Safety Training.
FLASH POSTER PRESENTATION
Response to PFC-Impacted Drinking Water Source at Moose Creek Community , AK
PFOA and PFOS were measured at concentrations exceeding the U.S. Environmental Protection Agency Drinking Water Health Advisory levels in tapwater from private supply wells in the Moose Creek subdivision, Alaska due to offsite migration of a PFOA/PFOS plume from Eielson Air Force Base (AFB). Moose Creek is one of the first Air Force/USACE projects to address PFOA/PFOS in a drinking water source and involves sensitive community relations issues and challenging conditions (rural, subarctic location with households requiring inspection and extensive upgrades to comply with building codes). The project included collection of more than 900 drinking water samples from 173 properties for EPA Method 537M analysis with no incidence of cross-contamination in the field or laboratory results. Results from 169 properties exceeded target threshold PFOA/PFOS criteria (i.e., one half the EPA Lifetime Health Advisory). EA worked closely with local, experienced general contractors to initiate sub-arctic winter construction methods and install treatment systems and below-ground storage tanks to support the time-critical schedule and eliminate exposure pathways. EA designed and oversaw the installation of point-of-entry granular activated carbon (GAC) drinking water treatment systems at 65 residential properties, and above- and below-ground water storage tanks at 94 properties. Properties included over 140 single-family homes, 13 apartment complexes, 3 commercial-size apartment buildings, 4 commercial facilities/bars, 3 churches, and one fire station. Regular source water testing was completed on all installed treatment systems, using a focused approach to evaluate the effectiveness of the treatment process and to confirm that the planned system was sufficient for effective treatment of PFOS and PFOA. More than 8 million gallons of water with average PFOS/PFOA concentration of 0.92 ug/L have been successfully treated with a combined total of 22,500 lbs GAC and generating 560 lbs of spent GAC. In addition, vertical aquifer profiling and low-stress, incremental sampling of groundwater was conducted between 100 and 285 ft. bgs to assess vertical extent of a 2-mile off-base portion of a 6-mile long PFOS/PFOA groundwater plume. Investigation determined PCFs impacted groundwater to 180 ft. bgs. Lessons learned will be presented, particularly relating to tailoring treatment systems for a variety of homes in a sub-arctic environment, built with minimal to no code oversight. Homes required a combination of mechanical and physical modifications, including excavation to install water storage tanks, construction of outbuildings for GAC storage, installation of soil absorption systems for backflushing, and construction of small enclosures to house pumps/pressure tanks.