July/August 2011
The proper techniques for sampling shredder residue or stormwater might seem complicated, but they’re worth the effort, experts say, because they can help a scrapyard avoid the compliance headaches a bad sample can create.
By Kim Fernandez and Diana Mota
Scrap recyclers love to grouse about intrusive government regulations, such as mandates to collect and test samples of their shredder residue or stormwater runoff. When they’re required to do so, they might begrudgingly send a worker out to the shredder with a five-gallon bucket, fill it with fluff, and ship it off to a laboratory in the hope that it will certify that the fluff does not exceed contaminant limits specified by federal, state, and local authorities as well as by the landfill that receives the material. Similarly, as often as their stormwater permit requires, they send someone outside during the latest rainstorm to scoop water off the pavement that they can have a lab test. All done, right? Wrong.
Such haphazard sampling techniques can create unnecessary problems. Poorly collected or improper samples can lead to test results that exceed benchmarks or limits when properly sampled material would not. In the end, such sampling could result in the landfill needlessly refusing a company’s fluff—or in expensive changes to the yard to reduce stormwater contaminants that are not truly at levels that require corrective action.
The risk, environmental experts say, is that the sample is not representative. If you happen to pull a sample of fluff after you shredded only one type of material, the sample will only represent that material and not the other materials you also shred. Likewise, scraping a bucket against pavement to grab a stormwater sample could pick up material from the pavement that isn’t actually running off the property, skewing the contaminant levels. Sampling improperly, these experts say, might be the only thing worse than not sampling at all.
Proper sampling techniques can be more time-consuming and complicated, and they might seem like a hassle, but they are the best way to ensure that samples accurately represent the material—and to ensure that you’re in compliance.
Sampling Fluff
When landfills or regulatory agencies require shredder fluff testing, they’re looking for higher-than-allowable levels of specific contaminants such as lead or polychlorinated biphenyls, says Rick Hare, safety director of Consolidated Scrap Resources (York, Pa.) and chair of the ReMA Safety & Environmental Council. Landfills can reject fluff that has excessive levels of such contaminants, forcing the scrapyard to send the material to special facilities that handle hazardous waste. “That creates a whole new set of worries and cost.”
How often a yard must sample its fluff varies according to the landfill’s requirements, experts say—it might be monthly, quarterly, semiannually, or annually. “When material is sampled, you’re getting a snapshot—a little, tiny picture of that big pile of shredder fluff,” says William Baumgartner, president of W.Z. Baumgartner & Associates (Franklin, Tenn.), and your goal is to ensure the sample accurately represents the characteristics of the fluff the shredder generates as a whole. “If you don’t have a good sample, the data mean nothing.”
The starting point, Baumgartner says, is the landfill or regulatory agency’s sampling requirements, which might specify how to collect the sample, how much of a sample you need, how to prepare it, what analysis procedure the lab should use, and the detection limits. With that information in hand, the scrap yard can develop its plan. “You have to know what information is needed,” he points out, “before you go out and collect samples.” Each sampling plan is unique based on the material being tested, generator, regulations, location, and final disposition, he says. If the requirements dictate a sampling protocol, recyclers must follow it or receive approval for using a different one. If one is not specified, the scrapyard must develop an appropriate one and be ready to defend it, Baumgartner says.
He does not recommend taking samples from standing piles of fluff for several reasons. First, “space is at a premium in a scrapyard,” he says. “Unless you have a really good reason, you don’t want to store shredder fluff.” The process also is more cumbersome, he says. You can’t just take a sample off the top or the edge of the pile. Getting a representative sample involves taking measurements and using heavy equipment to get samples from all over the pile. “You have to get inside that pile to make sure you have a three-dimensional representation,” he says. Most yards prefer to sample the material as it comes off the fluff discharge chute or conveyor.
He also is cautious about using a sampling method the EPA developed for bulk product waste: A worker fills a five-gallon bucket with fluff from the discharge shoot—which takes about 1½ to 2 seconds—every hour for eight hours. The worker then mixes all the collected material together in a 55-gallon drum and divides it into four equal, numbered samples. A random-number software program chooses one of the samples for testing. The EPA method might not be as representative as other methods, Baumgartner says. A typical shredder can process a car every 30 seconds, yielding about 350 pounds of fluff per car, he says. By collecting fluff for a few seconds each hour over eight hours, “you’ve sampled maybe one-tenth of eight automobiles.”
He prefers a method he developed about 30 years ago, which he continues to tweak. For five or six minutes, one of his technicians stands next to the running conveyor belt that discharges the fluff, constantly collecting representative pieces. He collects a wide variety of material based on what he sees coming down the conveyor. At the end of that time, the technician has about 1,500 to 2,000 grams of material—about 20 to 40 pieces of fluff. The technician repeats the process immediately until he has 10 to 20 samples. “It takes about an hour and a half to three hours to properly conduct a sampling event,” Baumgartner says. “Over the entire time period, we’ve collected material from about 180 to 200 automobiles and many more appliances, so we’ve got a pretty good representation.” Although a scrap yard employee could collect the samples using this method, there’s no way to ensure the person collecting the samples doesn’t bias the results by what he or she selects. “That is why we recommend the samples be collected by experienced, outside personnel,” he says.
His company sends the samples to an affiliated laboratory, which randomly selects three of the samples for testing. “The person taking the samples doesn’t know” which samples the lab will test, he says. The data from the analysis are reviewed statistically to provide a valid test result, he adds. “It’s a valid way of generating data.”
Michael Place, president of Continental Placer (Wheaton, Ill.), prefers a seven-day sampling method. A worker collects shredder fluff from the discharge conveyor each day at the same time for seven days. At the end of the seven days, the yard mixes the samples together and then separates the mixture into four to eight piles on top of a plastic sheet. The company chooses up to three of the piles at random and sends them to a lab for analysis. Some labs might disregard material such as large pieces of foam, he says, so his firm “pre-processes” the sample, making it more representative of the yard’s shredder fluff. Also, he points out, “When the foam is pre-processed, you can see that the inside of the foam is clean and free of oil.” (Any lab should break down the larger pieces of fluff so they fit into its analytical equipment, says David Wagger, ISRI’s director of environmental management.)
Consolidated Scrap Resources uses an outside firm to sample its fluff because doing so ensures that the samples are taken correctly, Hare says. “That does not relieve us of our responsibilities,” he notes. “We still have to do due diligence to make sure we’re doing our [sample] testing and our training [of workers to remove hazardous material], but it’s a shared effort.” Baumgartner recommends using a professional for another reason: “If there’s some legal issue, I can testify as a legal expert that the sampling was done correctly,” he says. If a recycler collects the sample and Baumgartner’s company just has it tested, “all I can testify about is what’s in the sample—not how the sample was taken or from where.” In other words, using an outside firm provides a higher level of credibility. A few states even require it.
Analyzing the Results
A fluff sample that contains contaminants over the regulatory limits isn’t necessarily hazardous, Baumgartner says. “It means something unusual may have occurred.” One possibility is that the shredder processed something it should not have at the time it collected the sample. “Recyclers are pretty good about removing items that would cause problems because those items aren’t going to make them any money,” he says. It’s important to educate and train workers about hazardous materials so they intercept contaminants before they go onto the conveyor and into the shredder, Hare says. Over time, his company has learned that that’s the best way to get a clean sample.
His biggest worry is PCBs, especially from capacitors. Though PCB-containing capacitors have not been manufactured for more than 30 years, when one appears it can wreak havoc with the fluff’s contaminant levels, he says. “Your results can be blown out of the water if one capacitor gets into your sample,” he says. “I educate our people so that if they see any kind of capacitor that looks like a vegetable can—it has a rim around the top—that’s an automatic flag that it could contain PCBs.”
That’s not the only possible cause of a questionable test result, however. Someone could have dropped the sample after it was taken, resulting in it picking up a contaminant, or the lab could have made an error, Baumgartner says. It’s important to find a lab that is familiar with shredder fluff, he points out, to minimize the chance of errors. Though many labs can properly conduct tests for PCBs, for example, they might be accustomed to testing soil or fluids, not fluff. Thus, they might use inappropriate testing methods. “They’re likely going to get a screen and screen the particles,” testing the screened material, which would not be representative, he says.
After a questionable result, the next step the yard takes will depend on what the regulatory agency requires. Scrapyards must plan for that next step, Baumgartner says, because it’s “going to happen” at some point. Sometimes it’s as easy as going back to what’s left of the sample for retesting. Some agencies could require additional testing over a period of months; others conduct a statistical review of the data. For example, in one state, when a sample exceeds the allowable contaminant levels, the state calculates the average for the past five sampling events. If the average is within the allowable limits, the yard passes.
Sampling Stormwater
As with shredder fluff, requirements for stormwater sampling vary from state to state. Some states, such as Maryland, don’t require sampling; others require it as frequently as quarterly, says Michael James, president of James Environmental Management (Round Rock, Texas). “For those that don’t, the day is coming,” he cautions. In states that require sampling, the only way to avoid it is to operate a completely enclosed facility in which no scrap or equipment is exposed to stormwater, says Larry Berndt, a principal with Wenck Associates (Woodbury, Minn.).
Many states now use five-year, multi-sector permits for stormwater—a single permit covers several industries and in greater detail than previous permits, Berndt says. Under these new permits, scrapyards typically must sample stormwater quarterly during the second year; at the end of that year, the results are averaged and compared to the benchmarks. “If you pass, you’re done sampling for the remainder of the permit,” he says. If not, “then in year three, you’re doing more site improvements, adding more best management practices, and doing whatever else you can” to improve your results. “In year four, you’re sampling again and hope to pass.” Most states are currently in their first year of sampling under the new permits, he says.
Most states require that facilities have their stormwater samples analyzed for sector-specific contaminants, which might include total suspended solids, chemical oxygen demand, pH levels, and total metals, including aluminum, copper, iron, lead, and zinc, Berndt says. When a stormwater sample exceeds the contaminant benchmarks, poor sample collection could be to blame. Scraping sample containers along the ground is a common mistake people make, he says. “Scraping the sample off the ground … could pull in more sediment than what’s really running off” the property, he says, which might skew the lab’s tests for total suspended solids. Additional sediment in the sample also could increase the levels of metals detected in it, he notes. “The ultimate goal is to have a ‘representative sample’ of what contaminants, if any, are actually leaving the site via stormwater. You don’t want to make the situation worse than it actually is.” Contamination also can come from stone that some yards use to protect the yard, James says. “If you just put down fresh stone, then your sample is going to fail.” If that happens, James recommends retesting. Yards that exceed contaminant benchmarks in their stormwater samples have not automatically violated their permit, Baumgartner says. They must respond to the appropriate state agency to explain what happened and what they are going to do about it, he says.
Stormwater sampling is easier than fluff sampling in some ways—the sample doesn’t have to be random, for instance—but it’s still an exacting process. Scrapyard personnel “can do the sampling themselves,” Berndt says. “You just need to be sure you’re sampling with care and collecting the sample properly.” The person collecting the samples should use proper analytical methods and preservatives and should label the sample bottles consistent with information on chain-of-custody documentation, he says. Calling a consultant to take a stormwater sample is more difficult, in fact, because the sample must be collected under specific conditions. “It would get cost-prohibitive to have someone to come out,” James says.
So what’s the best way to do it? Facilities regulated under a multi-sector general permit must follow the permit’s requirements. Permits often say to collect a sample within 30 minutes of when the rain starts, Baumgartner says, because “the longer it rains, the cleaner the runoff might become.” Along the same lines, permits might say not to take a sample if it has rained within the previous 72 hours. If a recent storm was “a gully-washer [or a] frog-strangler, it could wash everything away,” he explains. It’s always good to fill the sample containers directly from a discharge point, Baumgartner adds. If that’s not possible, he recommends using a laboratory-cleaned dipper to collect the sample. After collecting the sample, the yard must verify it was from a qualifying rain, one that resulted in at least one-tenth of an inch of rainfall.
To learn best practices for collecting stormwater samples, Wenck recommends that scrapyard owners and environmental managers attend local seminars or webinars on the subject, which a variety of companies offer year-round. Some firms, including W.Z. Baumgartner and James Environmental Management, provide training and a kit that contains the vials of testing chemicals. “We train [scrap companies] and provide everything they need,” James says. The kits come with detailed directions written in layman’s terms, with information as basic as “secure the cap tightly.” Companies that use the kits ship the vials back to the consulting firm in a cooler filled with ice, using next-day shipping, and the firm sends the samples to a lab for testing. Results typically take a couple of weeks. The firm also fills out and files any required documentation. Keeping good records is almost as important as doing the actual sampling, Berndt says. “Keep accurate records of sampling dates, chain-of-custody records, and analytical results as well as copies of your monthly inspection forms. Keep it all in a file and know exactly where that is.” This step also provides a favorable first impression, he adds. “First impressions are very important with regulators.”
Kim Fernandez is a Bethesda, Md.-based writer. Diana Mota is associate editor of Scrap.
The proper techniques for sampling shredder residue or stormwater might seem complicated, but they’re worth the effort, experts say, because they can help a scrapyard avoid the compliance headaches a bad sample can create.