2005-07-26_PWETC_AgendaPacket - Laserfiche WebLink

Home

Using this contamination data, the gross weights per household were then adjusted by subtracting the contaminants to create the comparison in Table 7 of net pounds per household collected per route in the "Before" and "During" periods for each pilot area. Table 7 shows the following results: . "During" versus "Before." The single-stream routes resulted in statistically significant increases in total tonnages recovered, even when their relatively high portions of contamination were subtracted out, as compared to the same areas collected as dual-stream routes in the "Before" period. . "During" versus "Before." The Two Bins route resulted in a statistiGally significant increase in total tonnage recovered, net of contamination, as compared to the same area collected in the "Before" period. . Tonnages recovered (net of contamination) for the other dual-strea111 pilot areas were not statistically significantly different "During" versus "Before." TABLE 7 COMPARISON OF NET! POUNDS PER HH COLLECTEDPJ<;R ROUTE BEFORE AND DlJRING THE PILOT Routes "Before" Pilot. All Dual Stream Routes "During" Pilot Net Average Contaminants', NetAv~rage Contaminants' Mean Lower Upper Mean Lower Upper Statistically (Avg. Lbs Range (A\ig.t9S Range Range Significant Collected Collected Difference per HH per per HH per Route) i Route)' Mon. 55 21.33 19.10, 2296 28.16 25.83 30.49 ./ Mon. - 55 Contrast 26.87 25.72 28.03 34.39 32.19 36.59 ./ Tues. - Weekly' 23.53 2,1.44 25.62 28.79 20.81 36.77 Wed. - Add!'1 Educ 21.73 15.84 27.63 25.30 22.62 27.99 Thurs. - Larger Bins 20.03 17.82 2223 26.87 23.29 30.46 ./ Fri. - Control 24.14 19.19 29.10 26.86 20.60 33.11 1 Average total pounds after contaminants were subtracted, 2 The range was calculated by subtracting the difference in pounds collected with and without contaminants (shown in Table 3) from the gross pounds collected per household. 3 "During" Pilot data represents weekly pounds multipliedby two in order to compare to routes collected every other week, 4 Derived from Appendix H Table 3 net average pounds per household calculations. Processing Residuals The previous section addressed contamination by residents at the curb, which was statistically significantly higher in single-stream than in dual-stream collection. Once recovered materials were collected they were all taken to the Waste Management/Recycle America Alliance (WM/RAA) MRF in Minneapolis for process mg. 20