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39 General Engineering and Environmental Management Services Southeastern Public Service Authorityf Virginia The Southeastern Public Service Authority of Virginia (SPSA) solid waste management system consists of a 2,000 -tpd RDF (refuse- derived fuel) facility, five transfer stations, and a 300 -acre landfill. All elements in this system were designed by HDR including processes, architectural treatments for all facilities, and the landfill. Early activity included a waste stream definition study where we established tonnages and quantities of waste produced, and projected future generation rates; seasonal variations and monthly fluctuations; and determined the percentage of waste that was recoverable, processible, and nonprocessible for landfilling. The recoverable and processible fraction was analyzed for potential energy yield. The RDF facility contains three process lines, two of which are operational at any given time, with one line always under maintenance. The process includes hand picking and magnetic separation of materials for recycling and three trammel lines for RDF production. RDF is transferred by conveyor to boilers at the nearby Portsmouth Naval Base electrical generating facility. REGIONAL LANDFILL, SUFFOLK, VA HDR has been providing landfill design and construction administration services to the SPSA since 1984. The 831 -acre site, which serves over 2 million people in the Tidewater area of the state, includes borrow areas, buffer areas, and perimeter roads. On peak days during the summer, this landfill has received more than 5,000 tpd waste. Our Carolinas office staff has designed and permitted over 185 acres of synthetic lined disposal cells and leachate treatment and disposal facilities for this landfill. The treatment facility consists of a 1.5- million gallon capacity lined aeration lagoon, which has been designed to accommodate the future installation of a clarifier and flocculation equipment. A second 1.5- million gallon capacity Tined lagoon is used as an equalization basin and holding area prior to pumping of treated leachate (meeting industrial pretreatment requirements) to the Hampton Roads Sanitation District Treatment Plant using a 400 -gpm pump station. Our Carolinas office staff also completed a landfill closure /post- closure plan for the existing Cell 1 - IV. As part of the closure plan, a comprehensive study was performed to evaluate the feasibility of developing a landfill gas (LFG) recovery system with electric power generation. The first phase of this system included conversion of the existing leachate underdrain system into a dual- purpose leachate /landfill gas collection system, which has been in operation since 1993. The LFG system has a 6000 kW generating capacity based upon the recovery of 750 to 1,250,000 standard cubic feet per day (MSCFD) of gas. Additionally, in an effort to minimize construction costs as SPSA struggles with the increased construction costs in the industry, HDR in conjunction with SPSA developed a plan to self - perform closure construction activities. With HDR's assistance, SPSA performed some of the closure activities while managing two subcontracts consisting of furnishing geosynthefics and installing the geosynthetics. SPSA served as the general contractor and performed all the civil site work on the closure. The money SPSA saved through this type of planning has allowed other projects to be funded with the savings. Our Norfolk and Carolinas staff provided Construction Quality Assurance Services for the closure project. HDR designed a 43 -acre cell expansion to the landfill to accommodate an additional 10 to 15 years of disposal capacity. The design of this new cell, designated as Cell V, included an innovative inward gradient design concept. Cell VI expansion (41 acres), also an inward gradient cell, was permitted and constructed in 2005/2006. Page 24 q