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Performance Effectiveness <br />Targeted Pollutants <br />This product has demonstrated both in the field and in the laboratory to be an effective structural treatment control <br />BMP for capturing trash, sediment, gross solids, oil and grease, and total metals. Recent testing of the DrainPacTm <br />was conducted by California Polytechnic State University San Luis Obispo resulted in 83% to 91% removal <br />efficiency of fine suspended solids with the best removal observed at lower flow rates, and oil and grease removal <br />efficiency varied from 40% to 80% under the test conditions. Higher rates of oil and grease removal can be <br />achieved by adding an absorbent sock around the periphery of the products frame (optional). See attached Filter <br />Testing Report for additional information. <br />Trash Capture & Storage Capacity <br />A DrainPacTm has a trash capture and storage capacity equivalent to the area of each unit. For drop inlets the <br />product will cover the entire length and width of the drain inlet point and standard filter depths are 12" yet can/will <br />be fabricated shallower to prevent the device from obstructing the outlet pipe of the catch basin. For curb inlets the <br />product will be fabricated to the length of the curb inlet opening with 12" wide by 12" deep standard dimensions. <br />Wider and/or shallower devices will be fabricated iflas required based on catch basin configuration. <br />Overflow or Bypass Flow Capacity <br />Drop inlet configurations of the DrainPacTm are designed with a center overflow bypass port to prevent flooding in <br />the event that a unit is full of trash and is no longer filtering. Curb inlet configurations of this product do not require <br />any type of special overflow bypass feature. If a unit is full of trash and is no longer filtering water entering the <br />catch basin will merely flow over the 12" wide device Into the catch basin. <br />Maximum Overflow or Bypass Flow Capacity <br />The overflow bypass features of the DrainPaclm described have been proven in the field to withstand a 10-year <br />storm event without causing flooding. <br />Siting, Operational & Maintenance <br />Installation Process <br />Before the start of installation United's Project Manager will coordinate with the County's Project Manager to <br />discuss the proposed installation schedule by service zones. For work performed in areas that encroach on traffic <br />right-of-way, an encroachment permit will be obtained from the appropriate entity and United will develop a written <br />and approved traffic plan. When proposed work zones have been accepted United will install DrainPacs"m in the <br />designated storm drains. <br />Devices installed in drop inlets will be gravity held in place and will rest on the existing catch basin grate shelf. For <br />this configuration installation will require United's Service Staff to remove the traffic grate using a 'traffic grate <br />puller" tool and will require approximately five minutes to install each device. Devices installed in curb inlets will be <br />mounted to the forward wall of the catch basin approximately 4" below the flow line or as required based on catch <br />basin design and/or other Storm Water Devices that may be installed in the same catch basin. This configuration <br />will require drilling of the interior of the catch basin and installation of supportimounting brackets (see attached <br />Technical Drawing) and will require approximately fifteen minutes to install each device. <br />Site Specific Measurements <br />The County would have to provide United with storm drain maps, inlet location where the product is proposed for <br />installation, and approximate lengths and widths of drop inlet openings and lengths of curb inlet openings in order <br />to provide Entities with cost estimates. Devices would thereafter be custom made to fit each respective storm <br />drain based on measurements taken by United's Service Staff. This device could be used in conjunction with a <br />CleanScreenl-m ARS and/or CPS for added effectiveness based on the level of trash and debris that commonly <br />p. 4