Improving existing technologies, creating national testing standards and focusing on niche markets can spring composting forward.

By Katherine Holden

Turning organic matter into compost isn’t a scientific mystery. Turning a profit…well, that’s another story. Fortunately there are new approaches to handling composting issues that help the industry achieve greater success.

Compost quality is an issue for those handling MSW as well as for those from an agricultural point of view. For the waste industry, it’s ideal to create compost that can be used (sold) rather than disposed of. With governmental imperatives to reduce landfill levels and with landfill capacities continually shrinking, finding better ways to make quality compost and finding more markets make perfect sense.

It wasn’t that many years ago when many jumped into composting, fueled by visions of compost empires. Dire predictions of shrinking landfill capacity, visions of flow control, and $100-plus per-ton tipping fees made composting look like the new promise land. "Man, we want a piece of this," people said, according to Sharon Barnes, owner of Barnes Nursery in Huron, OH, and the president of the United States Composting Council (USCC) in 2000. "Perhaps 15 to 20 $30 million plants, involving high-tech composting systems, were built and then closed," she adds. "Many monstrous plants, based on a big projected flow control, didn’t pan out. And if there was MSW in the big plants, it was impossible to sell the finished product because the quality was so poor with garbage, glass–everything in it. Yet they counted on the back end money flow of selling the finished product."

For many, the big compost dream melted like today’s tech stocks. For others, holding to the steady course–the turtle rather than the hare–continues to bring important improvements and innovative approaches, which help transform the basic good sense of compost into a good, growing business.

Matt Cotton, president of Integrated Waste Management Consulting in Nevada City, CA (and a board member of USCC), explains, "Basically there are three levels of composting technologies: (1) open windrows–you turn the materials, (2)aerated static piles–forcing air in via ducts, and (3) in-vessel–a totally contained system in big drums. There are hybrids of all these." One issue facing composting is odor control. Cotton, who permits and develops sites, says material can be processed so that odors don’t bother people. "It involves siting, operations, and a good basic composting knowledge." He adds that people have two choices: "Either you can increase the process control [which increases costs] or you can find a new site."

Most people interviewed for this article believe it is not possible to achieve total control of odor. According to Jack Hoeck, president of Rexius Forest By-Products Inc. in Eugene, OR, "There’s always going to be a certain amount of odor, even with incoming materials, what they are, and the time of year. Plus there are climatic conditions [such as wind flow] and how sensitive and close neighbors are."

Says Oley Sheremeta, president of Sheremeta Environmental Consultants LLC in Bellingham, WA, "As an industry, the technology of odor control has risen. There’s less generated, and what is generated is better controlled. The market is more sensitized to odor–how to control odors on the first hand and how to deal with residual odor. We learned how to manage it much better over the last 10 years." Dave Hardy of California Biomass, an independent compost facility near San Bernardino, CA, points out, "Technically you can reduce odors. The conflict arises if these measures are not enough to satisfy the local residents. Once they are [angry] and organized, your days are numbered."

Jan Allen, senior technologist at CH2M Hill in Seattle, WA, states, "You can’t compost without odors, but you can minimize odors to levels that are acceptable. We can get down below a problem level, that’s for sure." Allen knows that firsthand. The Cedar Grove composting site received 3,224 complaints in 1997. In 1998, that number dropped to 232. In 1999, 178 people complained. As of February 20, 2001, the site received only 48 complaints. Three things happened at Cedar Grove to reduce odor issues. Allen says, "They expanded the biofilters; they applied an Environmental Management System, which is structured to comply with ISO14000; and they had a much tighter control over the feedstock preparation by controlling the percentage of grass." Feedstock at Cedar Grove includes landscape materials (e.g., grass), foodwaste (primarily vegetable), woodwaste, wax-coated cardboard, and land-clearing vegetation. For these feedstocks, Cedar Grove uses aerated static piles and biofilters. It has also undertaken a residential postconsumer program, including meats and fats, in an enclosed process.

Allen says he’s spending most of his time converting windrow facilities to alternative technologies because of the odor problems with windrows. The original concept of windrow composting "made sense in an arid environment as a means to drive off moisture as the materials composted. They definitely do not make sense for wet or cold climates or for urban areas. So the technology has been applied in places where it probably shouldn’t have."

Rexius Forest By-Products, a 45-year-old company, started out recycling woodwaste. As restrictions on burning took hold, the company began making soil amendments and in the early 1990s began composting yard debris. "That was the first time we had to take materials on a daily basis," Hoeck recalls. "So we set up a windrow system, turning the material with a front-end loader. It was a low-tech system." Allen came up with a low-cost aboveground airflow technology that allows Hoeck tremendous flexibility at a quarter of the cost of an engineered site. He says, "Paving and buried pipes were too expensive considering our tipping fees. So we adopted that technology to an aboveground system where we don’t need paving or trenching. An ocean container holds the motor, fans, controls, et cetera. It’s lockable but not a concrete building. The piping is aboveground, and it slides together with a series of manifolds, and the pipes go under the piles. We can push air through or run negative air, pulling air back through and exhausting it." Odor control can be improved because pile surface area, agitation frequency, and surface emissions have all been minimized. One pilot study at a windrow facility measured odor reduction at 98% while reducing the footprint of the facility by nearly 70%.

The advantages of the air system are: (1) You can control the amount of air; you don’t have to rely on turning the material. (2) You can filter the air. (3) Moving air through helps with heavy winter rains, so in the spring the material is softer and easier to screen. "We still move the material about every three weeks," Hoeck adds. "First we pull out the pipes, then we remove material and move it down one section. The technology is nothing really new; it was developed for biosolids by the Department of Agriculture [USDA] in the 1970s in Beltsville, Maryland. They had a series of fans with pipes there, a pile of wood chips with pipes, then biosolids, then 8 to 10 inches of sawdust for an insulation blanket. Airflow in the bottom of the pile and an insulation blanket on top made all the biosolids go up into temperature. Those systems only blew out air. There wasn’t an option for negative or positive air, nor were there any removable pipes."

Hoeck’s flexible, basic, dual-air Express Composting System with a biofilter costs about $140,000. The system will process about 3,200 yd. at any one time. "That can be expanded," he points out. "With yardwaste, it can handle 6,000 yards. We can expand the system up to 9,000 yards with our material." With biosolids and chicken manure, fewer yards can be processed as a result of the need for a higher airflow. Hoeck says he’s just started marketing this simple and efficient system, which can be assembled and started up in less than two weeks. Because it’s appropriate for feedstocks with moisture levels between 50% and 60%, it’s an ideal system for mixtures of foodwaste and biosolids as well as greenwaste and woodwaste.

Another new millennium approach comes from Jim McNelly, president of NaturTech in St. Cloud, MN. In February 2001, McNelly began his Renewable Carbon Management (RCM) composting venture. RCM will use patented modified Intermodal shipping containers with a 110-yd.³-capacity, twice the size of the modified trash rolloff containers. Instead of selling equipment, as NaturTech does, McNelly says, "We’ll enter into strategic partnerships. I’ll be part of the operations to keep the business focused, plus it puts me back into operations. I’m the first person to operate a commercial composting facility that picked up grass clippings and other yardwaste from the curbside in Northglenn, Colorado, in 1976."

RCM will go after larger facilities, starting at 120 tpd. "Our optimum size is 300 tons per day, where we’re the most economical. We call it our ‘sweet spot.’ We’ve got five different venture partners currently negotiating with us. We’re looking at projects in China and Belgium and with three different firms in America." RCM will be a facility-developing company for other clients. The feedstocks it’ll use will be mostly raw wastewater treatment solids. "One of our NaturTech facilities proved we can handle most wastewater treatment plant biosolids to make Class B solids. We’ll take primary sludge only a few days old and thicken and treat it by going directly to composting."

McNelly knows he can do this after what happened in Coldspring, MN, working with Mississippi Topsoils, who took raw chicken blood and fat from a slaughterhouse that axes 200,000 chickens daily. "For the last 15 months they’ve proven they can go from raw sludge to compost," he states. RCM will be the marketing agent for NaturTech. Intermodal will not be for sale; McNelly will only work through strategic partnerships. Where NaturTech can handle 60-100 tpd maximum, RCM can work with 120-300 tpd.

Concerning odors, McNelly says, "One of the things we learned at Mississippi Topsoil was how to turn the compost curing system into the biofilter. In the past, NaturTech sold separate biofilters [also rolloffs]. Now they no longer have the extra expense of biofilters. We’ve cut the cost of composting in half over what NaturTech used to do. NaturTech used to be $35 per ton for capital and operating expenses. The RCM system costs less than $20 per ton and some operations are as low as $9 per ton. We’re very, very affordable. This isn’t for the faint of heart to go after 300-tons-per-day capacity, and all of our numbers are based on seven days a week, 365 days a year."

The feedstocks that RCM will go after include (1) wastewater sludge, (2) dewatered pig manure, and (3) mixed solid waste in developing countries. McNelly remarks, "I don’t like mixed solid waste because there’s so much contamination with glass, batteries, and so on. But we’ll do both source-separated [clean] compost and mixed waste [dirty] compost at the same facility.

"My system is unique. To be a part of a wastewater treatment, we have to be designed into it. Thus, we’re doing a lot of work in Asia, where there are no wastewater treatment plants at all. We totally bypass the anaerobic or aerobic system," he observes, adding, "I believe that renewable carbon will be to the 21st century what fossil carbon was to the 20th century."

RCM is also eyeing municipal wastewater treatment plants for communities greater than 100,000 in size. "If those plants are now biologically overloaded, we can help them avoid some expansion costs by taking on the solids."

RCM is ready to look closely at food processors, existing plants needing to expand, and the rest of the world without existing plants. What about large metropolitan areas? "We’re aggressively looking at Manhattan now," McNelly shares. "It has a lot of commercial foodwaste, and it’s very wet. Trash haulers in New York now use Intermodal containers, very similar to my design, to haul trash away by train." He likes the train hauling option, as highways legally allow only 22 tons of weight. "This helps take the stress off the highways." Also, the compost can begin curing while in transit. "Perhaps the curing can take place within the city. We can create Class B ourselves for land application."

McNelly is looking at train and shipping companies to be strategic partners. "Perhaps we can ship waste overseas, and by the time it arrives, it’s more cured than when we left port. The product can be used for sustainable agriculture. Right now nobody overseas can afford to buy compost. We can build a totally mobile compost unit where shipping and processing go on at the same time. Also, my containers can be used to ship back any kind of goods, although we may need some kind of liners. We have the option of mixing and preprocessing right at the existing port authority container-handling terminals that exist throughout the world. Port authorities are exempt from local and state laws concerning the types of materials they can handle."

McNelly is thrilled that at last composting can compete with landfills on cost, "and we’ve found a way to reduce transportation costs, as it can be shipped by rail far more economically. We can do this in a way that gives the client assurance that it will work because we’re part of the business."

According to Ron Alexander, president of R. Alexander Associates Inc. in Apex, NC, and program manager for the USCC’s Seal of Testing Assurance (STA) Program, there is a growing interest in compost certification within the composting industry. In 2000, the USCC ran a STA pilot project at 42 sites. The Environmental Protection Agency (EPA) funded development of the program. STA is a voluntary program for USCC members and nonmembers "to help develop more confidence in end users, to make compost more mainstream in horticulture and agriculture. We’re standardizing," explains Alexander. Already 70 companies have contacted Alexander for more information. "In 2000, we had 1.5 million cubic yards of compost certified. We hope for 2.5 million in 2001. To be successful, we have to sell the seal to end users, such as the state Departments of Energy." Alexander is heading a USCC program with that aim in mind.

The USCC’s Seal of Approval is the first nationalized testing program for compost. Hoeck says, "When you’re testing compost materials, unless you’re using the same laboratory procedures, the lab could choose test method A, B, or C. And the values may be stated in three different ways. The numbers don’t compare because the methodologies are not the same. Labs need to use the same test methods all across the country."

The STA Program is a compost testing and information disclosure program that uses uniform testing and sampling protocols and requires the disclosure of test analyses and product ingredient data, as well as end-use instructions to compost customers. "Without uniform testing methods, end users of compost will not be able to make proper purchasing decisions," notes Alexander. "The landscape/nursery, turf, and agricultural industries should know that the composting industry is dedicated to becoming a mainstream supplier of high-quality soil products to them. Green industry companies should look for the seal [of approval] when they buy their compost and other soil products."

While the USCC has about 200 members, Oley Sheremeta points out, "We have 4,055 compost plants in North America, 344 of which are in Canada." Although costs are an ongoing issue for composting operations, Sheremeta adds, "All are defraying the cost, or they wouldn’t be doing it. They’re taking in feedstocks with or without tipping fees. They’re using various technologies, and all are making a profit even though they may not be making a lot of money."

The more the thousands of compost operators utilize the STA testing and information disclosure program, the more end users will feel secure using the various compost-based products. Stuart Buckner, current USCC president, says, "We also have to raise the bar for training and certification programs so producers create a higher-quality product. We have to train operators to produce quality products. STA will improve customer confidence in the product." Sharon Barnes agrees: "The biggest drawback to this industry is that so many public and private facilities are poorly managed. When huge problems at facilities hit the media, it makes it hard to build another. We must raise the bar in appropriate technology and product quality. Pick the right technology for the right place, for whatever your level of operation, from the smallest to the largest. It must look good [not like a dump] and be well managed. Operator training and getting those operators involved in state and national organizations are important in order to reach the legislatures that regulate policies."

A 45-ft. digester

Buckner suspects that recent bans on land application of biosolids might lead to an increase in composting in some areas. Since MSW composting remained about the same the last few years, however, he does not envision an increase in this arena unless landfill costs increase significantly. Food-residuals composting projects is where he expects to see the greatest growth.

As the composting industry grows and matures during the next several years, Buckner believes there will be increased levels of standardization throughout the industry in terms of training facility operators and production of high-quality compost products. Moreover, increasingly stringent requirements on product testing and evaluation, greater reporting and dissemination of data, clear and concise recommendations for product application and use, and uniform requirements the product labeling will result in increased consumer confidence in the use of compost products.

Buckner anticipates greater production of high-end products and custom blends for specific markets–golf course blends, container media, manufactured soils in general–to meet various specifications such as disease-suppressive composts.

For Jack Hoeck, the STA testing of Rexius’s compost costs about $1,200 per year. "It gives us more credibility in the marketplace. STA gives the compost industry a more professional product to sell. Quality control was a big problem for golf courses and nurseries." Alexander says, "Ours is a striated industry, with very good composters on top and, at the bottom, people who just pile it up. I now realize there’s no way we can pull all the people up above the high bar. We need to keep raising the bar and pulling people along with us."

What about new markets for compost and emerging markets on the horizon? Alexander and others talk about the increase in niche markets for compost. Alexander says, "A great example of the beneficial impact of co-composting is that one can make specialized recipes for specific composts. People are now thinking and making niche products." observes John Heekin, president of Fecon in Cincinnati, OH, a company selling composting equipment, "Our business is growing due to the ongoing replacements of machines and the need to buy equipment to make compost more niche-specific, more marketable."

A paper published by EPA, titled "Innovative Uses of Compost–Erosion Control, Turf Remediation, and Landscaping," states, "Compost used for a specific purpose or with a particular soil type works best when it is tailor-made or specially designed. For example, compost that is intended to prevent erosion might not provide the best results when used to alleviate soil compaction, and vice versa. Technical parameters to consider when customizing a compost mixture include maturity, stability, pH level, density, particle size, moisture, salinity, and organic content, all of which can be adjusted to fit a specific application and soil type."

According to the USDA, the United States loses more than 2 billion tons of topsoil through erosion each year. Talk about a market for compost berms and blankets! And with turfgrasses, the EPA paper says, "some turf managers are now using compost to replace peat moss in their topdressing applications based on its proven success in suppressing plant disease. When properly formulated, compost, unlike peat moss, is teeming with nutrients and micro-organisms that stimulate turf establishment and increase its resistance to common turf diseases."

For landscaping activities, the EPA paper continues, "Increasingly, compost is being used as an alternative to natural topsoil in new construction, landscape renovations, and container gardens. Using compost in these types of applications is not only less expensive than purchasing topsoil, but it can often produce better results when trying to establish a healthy vegetative cover.… When used as a topdressing, or periodically tilled into the soil, compost can stimulate plant growth, reduce pest and plant infestation, and improve soil structure."

Concerning the use of compost in erosion control, Hoeck says, "It’s another tool in the toolbox." He talks of what’s happening in Eugene, OR, where builders need erosion control plans up front, and some use pyramid-shaped compost berms around the perimeter of the site instead of a filter fabric or sediment fence. The berm is 2 ft. wide at the base and 1 ft. tall. Rainwater filters through and either slowly releases or is absorbed into the ground. Another technique involves an erosion control compost blanket where material is blown onto a slope 2-3 in. deep, as well as pyramid berms at the top of the slope. The berms slow and filter the water and the blanket helps retain and infiltrate the water. "There’s much less runoff," Hoeck notes. "On a really long slope, you can use a series of pyramid berms along the slope. If you want plants on a freeway embankment, a compost blanket provides a more beneficial environment in which to establish vegetation than straw hydroseeding does."

Ron Alexander also talks about the growing interest in using compost for environmental purposes. "[Various state Departments of Transportation are] looking at compost for erosion control, to filter contaminants in flood water. Compost in the ground holds more carbon in. It sequesters airborne carbon, slowing the greenhouse effect. Recent research at a university in Austria found that an 18-inch layer of good compost on closed landfills oxidized methane."

Jean Schwab, program analyst at the USEPA Office of Solid Waste, outlined the title of the Austrian study, "Alternative approach to the elimination of greenhouse gases from old landfills," presented at the 3rd Swedish Landfill Symposium in 1998 by Marion Humer, P.E., and Peter Lechner, P.E., Ph.D. They also published the abstract under the title "Microbial Methane Oxidation for the Reduction of Landfill Gas Emissions." Schwab ponders intriguing questions: "Is 18 inches the ideal depth of the compost blanket, and need it be applied only once? Must it be maintained and, if so, for how long?" She figures it doesn’t have to be top-quality compost, and perhaps sites could combine the compost blanket with trees. "This could be perfect for smaller facilities," she says. She adds that EPA soon will undertake a joint initiative with Waste Management in Kentucky to test bioreactors and to verify the methane oxidation with the compost cover.

Multiple, stacked 45-ft. digesters

Another market for compost includes bioremediation. An example is using organic materials to clean up oil spills. Sharon Barnes points out that this is a low-tech way to clean up high-tech problems, including soils around munitions plants. "When you add organic materials to soils, you improve the water quality as it flows through the improved soils."

Scott Gillilian with Earth Systems in Bozeman, MT, shares information on a project involving composting and manure management on the lower Gallatin River in Montana. The primary goal involves showing that the production of compost, using manure from local dairy farms, can be an effective tool for the management of manure in the lower watershed. He says, "Demonstration of local and regional markets for the compost will ensure the sustainability of compost as a management tool. A secondary goal is to demonstrate that the compost produced can be used effectively as a soil amendment/fertilizer to enhance production of local crops." The lower Gallatin River watershed is on the 303(d) list of impaired waters and has the highest concentration of dairy farms in Montana. "It is also one of the fastest-growing areas in the state," adds Gillilian. A proactive approach to manure management will help local producers move toward compliance with state and federal regulations regarding animal feeding operations and meet the state’s nonpoint-source reduction goals. At the same time, this operation will turn a potential environmental liability into an economic benefit that can supplement producer income."

Earth Systems works with local producers to produce, market, and sell a minimum of 4,000 yd.³ of high-quality compost during the three-year project. Gillilian notes, "We consistently meet with excitement and encouragement about this project from agency personnel and farmers alike. However, in our naiveté, we encountered time-sucking stumbling blocks in obtaining permits and contracts. Although we consider ourselves a bit behind schedule, we continue to field inquiries from potential buyers of compost, which leads us to believe that marketing the bulk product may be one of the easier parts of the project. With the increase in energy and fertilizer prices, we hope composting will look more attractive than ever as a natural component to modern agriculture."

It’s a timely project. Barnes points out, "Manure management is becoming huge. EPA is going after nonpoint solutions for rivers and streams." Raw manure contains at least four constituents that pose potential environmental harm: agricultural organic chemicals (pesticides, antibiotics, hormones), pathogens, soluble nutrients, and weed seeds. Barnes says there is 106 times more manure generated per year in America than biosolids. "They used to be able to land apply manure without much question, before residential neighborhoods moved to the country, before industrialized forms of feeding lots, and before the concern of pathogen residue on the land."

"Composting Grows Stronger," a paper written by Susan Antler, executive director of The Composting Council of Canada, states that "more communities and enterprises are realizing that organic materials should be treated as resources rather than waste, providing the raw materials for the composting process.... Large-scale composting ‘factories’ continue to strengthen their presence across the country, capturing organic feedstocks and transforming them into valuable products for a variety of markets and applications."

"In 2020, things will be totally different," Barnes says, because people will be looking at "waste handling" as "material handling." She mentions Honda’s edict that by 2010 there will be no Honda parts going to landfills. This means zero waste. Materials will be trucked to various handling streams and reworked into the system. She says more and more companies are looking at ecoindustrial systems. Several food companies, when searching for new sites, "consider everything they do concerning residuals and what they’ll do with them before building. So they’ll eliminate residue from landfills," Barnes says.

She admits that landfill volumes haven’t gone down with all the recycling and composting going on, but she points out that there are fewer landfills today than 10 years ago. With Montana’s landfill life expectancy hovering around 1,500 years, diversion doesn’t seem likely to take center field. In Massachusetts, with a landfill life expectancy of only 1.8 years (according to Sheremeta), it’s a different story.

Today there’s a kaleidoscope of methodologies, resources, and opportunities for turning waste into compost. The cost of the process varies wildly. As Dave Hardy of California Biomass says, "Cost is the most guarded secret in the industry by each operator. The cost to transport a ton of greenwaste [curbside] is the highest, processing is the second, and the transportation to the user is the third. An average for California is $18 to $22 per ton charged as a tip fee and $8 to $12 per yard/ton for delivery of the product to the end user. Every operator [in California] has a different cost structure. This is due to a number of variables, such as accounting practices, equipment, maintenance, fuel cost, labor cost, and how many competitors or alternatives are available in the area."

Every step forward, in terms of tweaking existing technologies, finding new niche markets, standardizing composting testing, training compost-site operators, and educating end users, means more nutritious soils returning to Mother Earth. Considering she is one source we all depend on for life, the biggest question might be what it will cost if we don’t compost.

Katherine Holden frequently writes on composting issues for MSW Management.