Laserfiche WebLink
' Performa Inc. • • <br /> May 7,2003 <br /> Page 11 <br /> ' The various classes of employees and truck drivers, along with their estimated water use rates, <br /> are delineated in the table below. We have made the conservative assumption that only one- <br /> eighth of the truck drivers passing through the facility will use the washing machines. <br /> Table 4. <br /> ' Total estimated average daily flow rate of the septic system. <br /> User Category Persons Use Rate Scale Line Total <br /> (Work Week al/da l erson * Factor** al/da <br /> Office Staff 23 13 5/7 214 <br /> ' (M-F) <br /> Mechanics(Daily, 3 shifts of 8 hours 15 13 none 195 <br /> each, 5 mechanics each shift) <br /> ' Weekday Truck Drivers(excluding 400 5 5/7 1,429 <br /> shower and washing machine) <br /> Weekday Truck Drivers(shower only) 200 14 5/7 2,000 <br /> Weekday Truck Drivers(washing 50 50 5/7 1,786 <br /> ' machine only) <br /> Weekend Truck Drivers(excluding 280 5 2/7 400 <br /> shower and washing machine) <br /> Weekend Truck Drivers(shower only) 140 14 2/7 560 <br /> ' Weekend Truck Drivers (washing 35 50 2/7 500 <br /> machine only) <br /> Grand Total: 7,083 <br /> *From Crites and Tchobanoglous, 1998. <br /> **Scale factor to account for different work weeks;5/7 is a five-day week,while 2/7 is for weekend only. <br /> ' By examination of Table 4,the waste water quality is generated from essentially three sources, <br /> toilet and sink waste water, shower waste water,and washing machine waste water. An estimate <br /> of the concentration of total nitrogen from these three sources was made. The concentration of <br /> total nitrogen from untreated domestic waste water ranges between 20-80 mg/L-N with a typical <br /> average of 35 mg/L-N. We estimate that bathroom use only would increase the concentration to <br /> F <br /> ' about 75 mg/L-N. The tptal nitrogen concentration of shower water and launjwateLjs- <br /> expected to be the equivalent to drinkine water�The total nitrogen concentration of drinking <br /> water is estimated to be 3 mg/L-N whose maximum contaminate level (MCL) is 10 mg/L-N. <br /> f OF RjO1 <br /> p'S o <br />