Recycling Potential Assessments (RPAs) provide accurate baseline data to measure the progress of your waste reduction programs and to quantify materials available for diversion and subsequent marketing to materials processors and end users. Also, they provide a check of the program effectiveness by identifying which materials are not captured by collection programs and instead end up at disposal sites.
The program design and field approach for an RPA can be tailored to meet a wide range of desired information needs and available resources. To this end, RPA methods are described below for conducting a streamlined study, including field methods, as well as resultant data objectives and costs.
One approach to a waste characterization study is to perform a recycling potential assessment (RPA). An RPA is a waste composition study for the purpose of providing quick, reasonable quality data. These studies are intended to target the presence or absence of recyclables; however, other waste stream components may be of interest as well (e.g., household hazardous waste (HHW), construction and demolition (C&D;) materials, yard wastes, etc.).
Sampling and sorting procedures for an RPA are similar to those for a full waste composition study, except that wastes are sorted into fewer waste components to target only critical data: up to 20 sort categories are used versus the typical 30 to 40. Also, waste samples are collected over a 1 to 3 day period, as opposed to a minimum of one week for a full study. Specific objectives of this study may include:
While the RPA will not replace a full waste composition study, it can provide program specific, reliable information at a lower cost. The cost of an RPA varies, depending on data objectives desired and the number of field days. Typically, RPAs are on the order of $8,000 to $12,000. The RPA approach does result in some loss of flexibility, including the ability to distinguish compositional differences resulting from the days of the week or variation by season. Typically, RPAs examine fewer samples by waste type (residential, commercial, institutional, etc.).
As an example, SCS Engineers conducted an RPA at a suburban hospital to provide a recycling program and disposal planning assistance.
The purpose of the RPA was to identify recyclables present in the waste stream and to assess the potential for increased recycling at the facility. The need for the RPA was due, in part, to rising disposal costs and a 25 percent statewide recycling goal. The RPA was designed to sort and characterize solid waste generated at the hospital during a 24-hour period. To this end, 19 waste categories were used to characterize the waste stream.
Results from the field efforts are given in Exhibit 1, showing a breakdown of the recyclable fraction of the waste stream on a percent by weight basis. Based on these data, the RPA provided the following insights into the hospital’s waste stream:
Recycled materials included: computer print-outs (CPO), newspaper, HDPE and PET plastic containers, clear and colored glass containers, and aluminum cans. Overall, these materials were recovered at a rate of approximately 50 percent of materials generated, with recovery rates of 30 and 74 percent for aluminum cans and CPO, respectively.
Because the overall recycling rate for the hospital was only 8 percent, recommendations were made to target additional materials for collection, as well as to improve the capture rate for established materials. For example, the RPA recommended the addition of corrugated cardboard to the recycling program and to purchase and install a baler for material handling/processing on-site.
RPAs are a useful tool for solid waste planning and collection system evaluation. For further information on waste characterization studies and RPAs, please contact us at Service@scsengineers.com.
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