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As discussed in Appendix G, Beck/Krivit reviewed literature regarding processing residuals. Tn addition, <br />WM/RAA did provide the results of an in�ernal study at the Miuneapolis MRF in 2003 of single-stream <br />residuals (Appendix F). Key items regarding residuals and cantatnination issues: <br />WMIRAA Studv <br />■ The VVM/RAA study was internal, and the information that was provided was in su�nmary form; thus <br />no critical review was possible. <br />■ The study was performed for materials collected anly from single-stream routes in the Twin Cities <br />area (normally this MRF processes material from non-single-stream sources as well}, and it showed <br />that 5.95% of total inputs became residuals. These materials included both containination by <br />residents a� the curb {non-targeted rnaterials) and residuals from facility operations (processing <br />residuals, such as dirt and very small pieces of material). <br />■ Note that this 5.95% number is actually below or at the low end of the confidence intervals for <br />contamu�ants found in the single-stream pilot study areas, which only include conta.mination at the <br />cwrb (see Appendix D, Tables 4 and 5), not processing residuals from MRF operations. <br />■ Beck/Knivit note that the WM/RAA study conside�red both the 2% o� color-sorted glass and 11°/a of <br />color-mixed, broken glass to be defined as a product. Were the 11% of color-mixed, brok�n glass not <br />considered to be a marketed, recycled commodity, the residual rate wauld be about 17% for this <br />facility. <br />■ No comparison of dual-stream versus single-stream residuals is available for this facility. <br />■ The study cited its production standard of an a�erage of 1.5% or less for total contamination <br />(outthrows and prohibitives) %r its newspaper grade with arx action limit of 2%. Tbe study stated that <br />sample bales pulled at random rnet this standard. <br />Other Studies <br />■ An R.W. Be�k study for the American Forest and Paper Association (AFPA) showed significantly <br />higher "prohibitives" in newspaper and mixed paper from single-stream versus dual-stream sonrces. <br />Another consulting study (Jaakko Payry Consulting and Skuxxxatz Economic Research) for the AFPA <br />showed an increase in net recycled tonnage from single-stream. <br />■ The Enreka Recycling pilot study in 2001-2, which used data from single-stream programs elsewhere <br />in the country, showed an average residual raie of aboui 16% when mixed glass is considered to be <br />recycled, and 27% when it is not considered recycled. <br />Bale Audit <br />Bale audits are conducted to assess the quality and composition of processed recyclable rnaterial. Four metro <br />area recycling coordinators were invited to witness a paper bale audit at the Waste Managemenfi/Recycle <br />America Alliar�ce (WM/RAA} NIRF in the fall o£ 2004. A crer�v took a finished bale of Number 8 News, <br />broke it open, removed non-taxgeted material and weighed the non-targeEed material -- prinxzarily other types <br />of paper such as boxboard, although there were a few containers. Tn consultation with its paper mill <br />customers, Waste Management set a standard of 1.5% (average} of non-targeted ma#erial — aiso called <br />prohibitives and outthrows. (Note: the Ynstitute of Scrap Recycling Industry 2004 standard for unwanted <br />material in a bale of Number 8 News is '/4 of 1%). The weight of the prahibitives and outthrows in the bale <br />was approximately 1.5%. This did not include fine parlicles of glass visible on some of the paper. <br />The exact percentage of bale material collected through a single-stream process was unknown because the <br />recycling coozdinators were not able to vvitness the paper being processed hefore it was baled. And <br />21 <br />