The Primary Settling Tank a. Using the EPA standards showing in table below, determine the size of the primary settling tank. Use at least two tanks operating simultaneously. Verify that the dimensions are correct. Show calculations for each of the following parameters: b. 1. Volume. 2. Detention time. 3. Overflow rate. 4. Weir loading. I TABLE 2 Typical Design Criteria for Primary Clarifiers OVERFLOW RATES-GALLONS/DAY/SQUARE FOOT (gpd/sq ft) AVERAGE MONTHLY FLOW 800-1200 1000 600-800 EPA Standards EPA with secondary solids SIDE WATER DEPTH-FEET (ft) EPA Standards EPA with secondary solids 10-13 7 13-16 WEIR LOADING-GALLONS/DAY/LINEAR FOor (god/tt) Standards 10,000-40,000 10,000 PEAK FLOW 2000-3000 1500 1200-1500