Site work for a water / sewer project in Portland, Oregon. Completed plans call for site work for a water / sewer project.

Treatment of Construction Dewatering Containing PFAS Question Deadline 02/21/2025 at 5:00 PM PT Online Q&A Yes, Through the Port's online bidding system. Questions received fewer than five (5) business days prior to the deadline for receipt of proposals may not be considered. Future construction projects at PDX will include underground facilities (e.g., utilities) that may be installed below the groundwater table requiring construction dewatering. Because of past use of firefighting foams, PFAS may be present in the groundwater in the project areas. Construction dewatering is subject to permits that place limitations on chemical concentrations in the discharge water and may include PFAS compounds. Unique features of addressing PFAS in construction dewatering at PDX include the following: o Although overall project durations may be months or years, individual work tasks may be in areas of active aircraft movement that could limit operation windows to a few days. o PDX is constructed on the Columbia River floodplain with highly variable soil conditions. Construction dewater flow rates may vary from less than 1 gallon per minute (gpm) to greater than 300 gpm. o Depending on project location, influent concentrations may vary from near detection limits to the concentrations listed below. Target treatment levels may vary from project to project. Discharge to sanitary sewer could require treatment to below detection limits, whereas land application requirements could be greater than EPA drinking water maximum contaminant levels (MCLs). Assume that the typical treatment target would be EPA MCLs. o The regulation of PFAS is rapidly evolving so discharge limits could change. Work may be in areas of historical releases of jet fuel. Treatment of water for PFAS would need to allow for the potential presence of petroleum hydrocarbons