# Problem Description Problem Set No. 6
1 A town of 90,000 people currently places all of the solid waste it generates into a local landfill. How many tons of solids waste do they generate in one year? [72,270 tons/yr]
2 In #1 above, if the town required its residents and businesses to separate the yard trimmings from the solid wastes that they generate, then how many tons will go to the landfill each year? [62,514 tons/yr]
3 Use Figure 5 in EPA_MSW_2012 factsheet.pdf and create a table that shows how
many tons of each material the town in #30 above would generate each year. The sum total of all these amounts should be equal the amount you calculated for #1. Then use the information given in Table 1 of EPA_MSW_2012 factsheet.pdf, and add
a column to your table for the tons of each material that could be recovered for recycling if the town recovered the same percentages of materials as is given in Table 1. Now how many tons of solid wastes would be going to the landfill each
year? { Hint: Take percent recovered for other as 15.1%} [47,241 tons/yr]
4 By what percentage would the town have reduced its solid wastes going to the landfill if it actually recovered the total possible amount calculated in #3 above? [34.6 %]
5~8 A city generates 650 tons per day of municipal solid waste (MSW) that has the following characteristics determined locally.
The MSW is collected by 20 cubic yard packer trucks on Monday,
Material % Tuesday, Thursday, and Friday. Wednesday is a day used to Paper 31.3 perform truck repairs and other maintenance. MSW from only one- Glass 6.0 fourth of the city is collected on each of these days. The landfill Metal 8.2 where this MSW is disposed has a total design volume of Food Waste 16.5 5,931,250 cubic yards, but over the years, eighty percent (80%) of Yard Waste 26.0 the landfill volume has already been filled. Assume that the Plastics 12.0 population, the MSW generation rate, and the characteristics of
Total = 100 the MSW will not change in the future. Answer the following questions.
5 How much MSW needs to be collected and then transported to the landfill each collection day? [1137.5 tons/day]
6 If a packer truck can compact MSW to a maximum density (in the truck) and if it can make 3 trips to the landfill each collection day, how much MSW can one truck transport to the landfill each collection day? [24 tons per day per truck]
7 In order for the city to make sure that the entire amount of MSW to be picked up on each collection day can be transported to the landfill, what is the minimum number of packer trucks that the city will need to have? Assume that all trucks have the same capacity as described above and that they will all make 3 trips to the landfill each collection day. [48 trucks]
8 At the current rate of MSW generation, how many more years will it be before the landfill
has reached its capacity if the maximum compaction within the landfill can be achieved? [4 years]