A question about TSS

Hi, does anyone can help me with this problem? I have a question about calculating TSS when I try to solve a problem in by Michael R. Lindeburg's practice book (Chapter 28, Q1)." A town of 10,000 people (125 gpcd) has its own primary treatment plant. What mass of TSS should the treatment plant expect? The solution assumes 800 mg/l total solids. How does this number come out? Anywhere I can refer to? Thank you very much.

Sounds like they are asking for the loading rate in lbs/day. They don't give you the 800 mg/L TSS number do they? That's probably an assumption made by the author and unless you know specifically which book he used it's likely you won't find that number. I checked Ten States Standards, my Davis & Cornwell, and Metcalf & Eddy book and none of them mentioned anything about typical total solids values. When I was studying and ran across these type of problems I added these "assumptions" in my homemade equation booklet. I never used them during the exam but you never know what might show up. To solve this problem I would assume this is how they did it (I don't have a copy of this book so it's a shot in the dark):

10,000 people * 125 gal/cap/day * 1 MGD/1*10^(6) gpd * 800 mg/L * 8.34 = 8340 lbs/day

Remember that the 8.34 is a conversion factor. To get loadings it's always MGD*mg/L*8.34=lbs/day. If my answer is correct then the only real hard part is how to determine the 800 mg/L concentration. That's one of those problems I would either skip or write down the assumptions for future reference.