Laserfiche WebLink
Near and Far Field Dilution Analysis of Manteca Discharge October 2006 <br /> • The diffuser would likely extend over more than 50% of the cross section <br /> therefore, the 1° F over 25% of the cross section would apply. The centerline <br /> (minimum) dilution would be a good approximation for estimating the <br /> temperature over 25% of the cross section area(see Figure 27). <br /> • Since complete mixing is the goal of the diffuser and there is no discharge at slack <br /> water, the 4° F surface increment would never be an issue. <br /> For any discharge, the maximum allowable temperature differential between effluent <br /> temperature and background river temperature would equal the minimum Acute dilution <br /> +1 (to get to 1° F impact) as illustrated below. <br /> An equation for"' concentration when temperature increment is 1° F,using minimum <br /> dilution: Dm \TRiver/l+TEffluent _ T +1 <br /> D,,,;n +1 River <br /> Therefore: TEfluent TRiver +Dmin +I <br /> Using the minimum Acute dilutions presented in Figure 10,we estimate maximum <br /> temperature increment for l' F impact over less than 25% of the river cross-section as <br /> shown in Table 4. <br /> Table 4 Estimated maximum temperature increment to satisfy 1°F criterion with diffuser outfall. <br /> Flow Minimum dilution (parts Maximum temperature increment <br /> river water per 1 part (° F) for 1' F impact over < 25% <br /> wastewater for Acute case cross-section <br /> 9.87 MGD 11 12 <br /> 17.5 MGD 7 8 <br /> 27 MGD 4 5 <br /> 33 <br />