25F - AGMT - DELHI DIVERSION PROJECT

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Preliminary Design Report Addendum No.2 Special Construction Trenchless construction techniques will be used for all pipeline crossings of major highways to avoid disruption in vehicular traffic. Route 3 contains one crossing, which will require special coordination and involvement with the applicable agencies. • Delhi Channel (HDD), 300 feet, 30 feet deep • Newport Beach Golf Course continue through 2031 Irvine Avenue (HDD), 600 feet, 10 feet deep HDD and jack and bore construction will be used to accomplish these major highway crossings. Additional information regarding the estimated cost of special construction is located in Exhibit B. Downstream Existing Pump Station Improvements Route 3 will divert flow into MCSD's existing sewer system, before it can enter the OCSD's sewer trunk main. The pump stations that will be impacted are the Irvine Sewer Lift Station and Elden Sewer Lift Station. The Irvine Pump Station was rehabilitated and upgraded in 2007. The most recent improvement for the Elden Pump Station was in 1990. The Irvine Pump Station is a duplex pump station equipped with two Flygt NP3202 Type MT, 8 "X8" submersible pumps with 60 HP motors. The Irvine Pump Station consists of two emergency storage vaults in addition to storage capacity in wet wells and sewer manholes at the pump station. The Elden Pump Station is also a duplex pump station equipped with Flygt CP -3300 pumps each with 60 HP motors. In this preliminary phase, we do not have detail design flow and head information of these two pump stations, and for rough cost estimation we assumed that both existing pump station wet wells and structures can be reused. Pumps will be replaced with slightly larger pumps from the same manufacturer ( Flygt), and the controls will remain in place. The installation cost of two new pumps to the existing Irvine and Ellden Pump Stations is estimated to be approximately $100,000 for each pump station. By including contingency of 100 %, the downstream existing pump station improvements are estimated to be approximately $400,000. Route 4 The limits of Route 4 begin at the proposed Delhi Channel Diversion Facility Pump Station and end with the pipeline connection to the existing OCSD's 27" diameter trunk main at the intersection of MacArthur Boulevard and Birch Street. This route begins at the proposed diversion facility location and proceeds north, crossing the Newport Beach Golf course, southeast to Bristol Street ROW, crossing Corona Del Mar Freeway, through the bridge's existing utility crossing structures, and continues southeast to Birch Street within the ROW. The route continues northeast within the Birch Street ROW to MacArthur Boulevard, ending at an existing manhole on the northwest corner of the MacArthur Boulevard and Birch Street intersection. Pipeline Length Route 4 is approximately 7,132 feet in length. Public Inconvenience & Safety The public inconveniences for Route 4 when constructing along the roadway include the major crossing at Corona Del Mar Freeway (including Bristol Street S. and Bristol Street. N) and two street crossings on URS 23 25F -155