Banking On Benchmarks

September 1, 1994

6 Min Read
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Jim Morris

For many years, determining a recycling program's success was easy - simply collect more material each year and report the good news to residents and pol-iticians.

But as community recycling programs mature, the concept of success may become harder to demonstrate. For well-established programs, hefty annual increases in tonnage become more difficult, and often more expensive, to generate. Most of the "easy tonnage" already is being collected, and most of the "easy to convert" residents already are participating.

Converting the remaining minority or adding new materials may require heavy investments in equipment, education or enforcement, yet they may produce only small increases in tonnage.

In economics, this phenomenon is referred to as diminishing returns. In recycling, the Law of Diminishing Returns predicts that operations will reach a point where each increased dollar investment in one aspect - equipment, education or personnel, for example - begins to produce smaller increases in returns.

This could mean that your annual recycling budget increased 6 percent last year but tonnage increased only 3 percent - or even declined. How-ever, as solid waste management costs continue to rise, residents and policy makers are demanding higher levels of accountability. In New Jer-sey, for example, the legislature is considering a bill that would require providers of public services to dem-onstrate that their operations are competitive with the cheapest public or private alternative. The move to-ward benchmarking is an increasingly common management tool that governments are requiring of their contractors and their own departments.

Following are some of the benchmarks that recycling coordinators have used successfully and unsuccessfully to compare their programs (see chart on page 50). Cost Per Ton: This calculation, in which the total annual cost of recycling is divided by total annual recycling tonnage, sounds simple, but calculating the total cost of recycling presents many challenges. In addition to the obvious costs of direct labor, equipment and supplies, it should include indirect costs and any costs incurred or revenues gained by disposing the material at a processing facility or end market.

Note that this calculation does not include avoided disposal costs, which are saved each time a ton of material is diverted away from a landfill or incinerator. Avoided disposal costs should not be used to calculate the cost of recycling; in-stead, include these costs in calculating the cost per ton for garbage disposal since that's where the expenses are incurred. In this manner, cost per ton can be compared for garbage disposal and recycling. Per Household Or Person: To calculate the cost per household, divide the total cost of recycling by the number of households served by the program. Be careful to exclude households that are not served by the program. Cost-per-household data reveals the cost to serve each household even if those costs are buried within a community's tax bill.

Determining the cost per person is useful because many other solid waste figures, such as average generation rates, are based on per-person figures. Cost per person is calculated by dividing the number of residents served by the program into the total cost of recycling.. Recycling Rate: Calculate the recycling rate by dividing recycling tonnage by recycling tonnage plus garbage tonnage. Although recycling rates have been calculated in many other ways, this method can provide a reasonable estimate of the percentage of solid waste that is being di-verted from solid waste facilities. Like any statistic, it also can be manipulated to greatly overstate recycling success.

The recycling rate can be manipulated in several ways. For example, the rate can be increased by adding recycling tonnage for materials, such as road asphalt or scrapped cars, that are not considered part of the municipal solid waste stream. The weight of the materials can dwarf tonnages for paper, aluminum, glass and plastic and, in turn, present a spectacular - but inaccurate - re-cycling rate.

Recycling coordinators may have trouble finding reliable tonnage figures because many solid waste rec-ords are notoriously inaccurate or incomplete. An accurate recycling rate also should deduct from the numerator any recycling tonnage lost to contamination if it ends up being dumped at the landfill or in-cinerator. For these reasons, this re-cycling rate can be an estimate only. However, it remains one of the best ways to determine the amount of garbage that is reused rather than burned or buried. Participation Rate: This rate is al-most impossible to accurately estimate. On paper, it appears to be easy: Divide the number of households that participate in a recycling program by the number of households eligible. For example, if a curbside recycling program offers service to each of the 2,000 homes on its bi-weekly collection routes and the crew counts that 1,200 homes set out materials during one collection period, the participation rate would be 60 percent.

But that number isn't completely reliable. First, it provides no information about how much material each household set out. If a family recycled only its papers but threw away its glass, aluminum and plastics, that family would be "participating." Second, the 60 percent figure assumes that households are not participating if they do not set out materials that week. Many communities offer drop-off centers to complement curbside programs, and households that recycle through drop-off centers would be counted as "not participating." Third, unless this survey is conducted repeatedly and at different times of the year, it will not be statistically valid. Instead, it will provide a potentially inaccurate snapshot of participation that week. Finally, this survey method works primarily in suburban communities with easily identifiable households. It is not valid if there are many apartment buildings with communal recycling facilities or in towns with large fluctuations in population, such as seasonal resorts or central business districts that at-tract many daytime visitors. Compliance Rate: This rate can be considered the flip side of the participation rate. Rather than answering how many households are participating, this number assesses the percentage of households that throw away their recyclables. The answer lies in the garbage bag rather than the recycling bin.

To answer this question, one New Jersey township conducted spot in-spections of residents' garbage bags during four separate collections. To calculate the compliance rate, the township divided the number of households in compliance by the number of households sampled. Of 253 households sampled, inspectors found recyclables in bags from 26 residences, so they estimated a 90 percent compliance rate:

* 253 - 26 = 227 residences in compliance;

Consult Printed Publication for Formula.

Like the participation rate, the compliance rate can be unreliable. For instance, how do you define non-compliance? Township health inspectors defined it as more than one recycled material in the garbage. A reliable number also requires a statistically valid sample size, and this system is not useful in areas with large multi-family or seasonal populations. Finally, some recycling coordinators are uncomfortable with the privacy issues raised by inspecting residents' garbage.

In Cook College's five-day recycling economics class, discussion of recycling benchmarks is called the "figures don't lie but liars do figure" session. At best, these calculations can provide some standards by which recycling programs can be gauged. At worst, they can be manipulated or misunderstood to become entirely meaningless or misleading.

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