Grindstone Recreation Area Wastewater Treatment Plant (WWTP) Analysis

Services under SRS Shortlist 12445121R0005 feasibility study should address the following challenges: ? NPDES permit requirements ? Aging treatment & collection infrastructure and inefficient design ? High annual maintenance and operation costs ? Remote system operation and management ? Seasonal operation and fluctuations SCOPE OF WORK PHASE 1: Feasibility Study and Assessment of Replacement Options The goal of this phase is to study the feasibility of various wastewater treatment options available to replace the existing WWTP, to compare and assess the replacement options, to recommend the most appropriate replacement option(s) and to provide a closeout plan for the existing wastewater treatment facility. This phase will include the following activities and deliverables: a. Review and document the existing Grindstone WWTP facility site and recreation facilities, operations, maintenance activities, historical records/documents, and NPDES permit. b. Review and document the recreation facilities currently served by the existing sewage treatment plant and evaluate projected wastewater flows generated by each facility. c. Review the sanitary sewer infrastructure serving the existing WWTP. d. Review the electrical and data/telecommunications systems serving the existing WWTP. e. DELETED f. Perform subsurface investigation and testing to develop and evaluate replacement WWTP options. It is assumed the USFS will provide an excavator to dig the test pits and PVC pipe for the percolation tests. Test pit locations will be approved by the Virginia Department of Health (VDH). It is assumed there will be a maximum of five test pits excavated with each test pit requiring a percolation test. Percolation tests will be performed by the prime contractor in accordance with VDH requirements. It is also assumed there will be a water source available on site to conduct the percolation tests. Correspondence with VDH has indicated the new WWTP will not require a VDH permit due to its location on federal land; however, all local and state rules and regulations will be followed. The prime contractor will handle all coordination with VDH as needed. For later phases of the project, VDH has offered to provide a cursory review. g. Items a. - e. will be completed during a 2-day site visit. h. A tv inspection contractor will be subcontracted under the prime contractor to perform gravity sewer tv inspection of approximately 6,000 linear feet of gravity sewer collection main. The tv inspection will be used to evaluate the existing collection system and inform recommendations. The tv inspection contractor will jet the existing collection system prior to the tv inspection. Recordings for all of the gravity sewer collection system inspections will be provided to the prime contractor. It is assumed that it will take approximately five working days to complete the tv inspection. i. Prepare a feasibility study report detailing replacement of the existing WWTP with simpler and more cost-effective wastewater treatment options. The alternative treatment options must eliminate the requirement for an NPDES permit and should be sited within, adjacent to, or close-by the existing WWTP. The feasibility study report should evaluate and consider using components of the existing wastewater infrastructure following some rehabilitation. However, the cost/benefit of new versus rehabilitation must be considered. The report, not including appendices, will be approximately 30- to 40-pages and will be used to scope the next phase of the project. j. Provide an assessment and cost analysis of the replacement options identified/recommended in the feasibility study to include comparisons of up to 4 options for treatment and collection (including a - no action alternative) identified in collaboration with USFS prior to detailing options. At a minimum, comparisons should include environmental impact, seasonal operation/fluctuations, operational complexity, remote operation/management, repair/replacement costs, system vulnerability to infrastructure failure, cost analysis (should include, capital/construction costs, annual operation and maintenance costs, energy savings and life cycle costs), certified operator requirements, options for phasing, implementation timeline, construction schedule and anticipated service life. A - best replacement option recommendation shall be made to the USFS as a final outcome of the assessment including estimated costs and schedules for design and construction. k. Prepare a closure plan outlining possible approaches for decommissioning the existing wastewater treatment plant prior to construction of the new wastewater system that would eliminate wastewater discharging and terminate the VDH DEQ NPDES or other operating permits until demolition of the existing can be completed while still providing limited operations and access to the recreation facilities. Potential closure concepts will be presented in a brief 3- to 4- page technical memorandum, not including attachment.