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<br />the mechanical screen on the left and the <br />manual screen on the right. The photo on the <br />bottom right shows the manual bar screen. <br /> <br />Debris collected !Tom both screens is manually <br />shoveled into 20-gallon garbage pails. The <br />mechanical screen collects approximately 13.5 <br />gallons of debris per day. Plant staff gather the <br />garbage pails weekly and dispose of the waste <br />at the local landfill. Screenings collection and <br />disposal are a high maintenance process and a <br />safety hazard due to close contact with the waste. <br /> <br /> <br />Influent Sampler <br />Wastewater is sampled !Tom the channel immediately downstream of the bar screens. <br />Samples are drawn into sampler tubing and flow to a 1999 model sampler unit located in <br />the grit room. The existing sampler is equipped with remgeration to preserve samples. <br /> <br />Existing F10w Measurement <br />A 12-inch Parshall flume is used to measure the <br />incoming wastewater flow to the facility as <br />seen in the photo on the right. This flume has a <br />maximum capacity of 10.4 MGD based on the <br />assumption that downstream effects on the <br />wastewater would not cause the flume to <br />submerge. An ultrasonic level sensor measures <br />the water depth and sends the corresponding <br />signal to an influent recorder. The recorder <br />converts level to flow and sends the flow <br />information to a totalizer, which drives a <br />counter showing total flow. <br /> <br /> <br />A crack in the floor extends !Tom the flume in both directions. The Parshall Flume was <br />inspected visually, but no conclusive evidence of its condition was apparent. Measuring <br />tape is attached to the side of the flume to allow for a visual observation of the water <br />depth. The markings on the tape near the bottom were worn and not readable. <br /> <br />Existing Grit Facilities <br />Grit is removed !Tom the liquid stream by a grit <br />tank. An 18-inch pipe is available to bypass flow <br />during tank maintenance. The grit tank is 10'-0" <br />long by 6'-0" wide by 4'-0" deep with a sloped <br />bottom. The current grit tank is undersized. At <br />the current peak day flow of 1.8 MGD, the 1,160- <br />gallon grit tank has less than one minute detention <br />time. Ten States Standards recommends a <br /> <br /> <br />3 <br />