Interim Measures Pilot Study Completion Report, South Repeater Building, Solid Waste Management Unit 121, Hydraulic Containment and Groundwater Treatment System for Per- and Polyfluoroalkyl Substances

This Per- and Polyfluoroalkyl Substances (PFAS) Interim Measures Pilot Study Completion Report was prepared for the National Aeronautics and Space Administration by AECOM Technical Services, Inc. under Contract 80KSC019D0010, Task Order 80KSC021F0096. The purpose of this report is to document the pilot study activities at the South Repeater Building, Solid Waste Management Unit (SWMU) 121.

This report details the additional assessment activities completed from June 2023 through November 2023 and the subsequent pilot study completed at the South Repeater Building conducted in December 2023 through February 2024. Initial activities were conducted in accordance with the Pilot Study Work Plan (NASA 2023), submitted to the KSC Remediation Team and accepted by the team on October 26, 2023.

The objectives of the pilot study were to:

• Provide information on aquifer characteristics and to aid in future modeling and remedial design activities to mitigate off-KSC migration of PFAS compounds.

• Develop information on characteristics of the surficial aquifer system, specifically transmissivity, storage coefficient, hydraulic conductivity, and vertical hydraulic conductivity.

• Obtain data to support construction and calibration of a groundwater flow model.

• Acquire design parameters necessary for future remedial design activities, specifically radius of influence, drawdown, flow rates, and pump settings.

The following activities were completed to meet the pilot study objectives:

• Groundwater and surface water sampling

• Geophysical investigation via Hydraulic Profiling Tool (HPT) and soil sampling

• Installation of observation and extraction wells via rotosonic techniques

• Slug, step, and pump testing activities

• Initial modeling efforts for a groundwater hydraulic containment system.

Results of the pilot study and modeling activities are being used in the development of a groundwater containment and treatment system for the site.