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June 15, 2005 | General

LARGE-SCALE COMPOSTING FACILITY THRIVES IN ST. LOUIS SUBURBS


BioCycle June 2005, Vol. 46, No. 6, p. 20
In these NIMBY days, it’s great to know an open, outdoor windrow facility remains in good public favor while operating full-scale within the community.
Rich Flammer

“DANG! That makes me mad,” says Dennis Bible, Public Works Director for Ladue, Missouri as we tour his composting facility. “What?” I ask, looking around unable to find anything that could possibly displease a composting operator. The 14 windrows on the five-acre facility, laid out straight as arrows on pads of either concrete, asphalt, or solid gravel base, depending on which part of the site they reside on, are also meticulously spaced, and uniform and symmetrical in size. A Scarab hums through one of the rows in the distance, and the air is filled with pleasant smells of a forest after a rain.
“Litter!” Dennis exclaims, and I scratch my head and strain my eyes looking for evidence in support of his discontentment. The windrows were pristine, and contained nothing more than leaves from the season’s collection. “There!” he says, and about 150 yards down one of the center windrows, a small whitish piece of paper comes into view as we walk towards it. Dennis bends over and picks it out the pile. It’s a gum wrapper, and in approximately 26,000 cubic yards of composting leaves, is the only contamination visible. This event not only exemplifies the immaculate condition of the facility, but also embodies Dennis’s keen management and dedication to the program he’s been overseeing for nearly 15 years. But even more remarkable than the cleanliness and picture-perfect symmetry of the facility’s layout, is the fact that utilizing a thermophilic, aerobic, outdoor open-windrow process, it peacefully coexists in close proximity to multimillion dollar homes in one of St. Louis County’s most affluent neighborhoods. The high-end residences that exist just to the south of the site are each built on parcels zoned a minimum of three-acres, and the closest of the stately dwellings are only 600 feet away from the operation.
Not only do Ladue residents enjoy the unobtrusiveness of the facility, they also delight in the finished product, which flows out of the site as fast as it is produced. In fact, this year’s compost was in such demand, the city had to impose a 12-cubic-yard limit to ensure more equal distribution. Even with the rations in place, some residents who waited too long still lost out, and by mid-March, the last of composted leaves from the 2004/2005 collection season were gone – delivered to homes in the surrounding neighborhoods – and the compost pad was bare.
Although the operation sounds almost too good to be true, things weren’t always so rosy. After battling numerous problems common to large-scale composting facilities – odor, capacity, and public perception – the program was once on the brink of being eliminated. Since those tentative days, challenges have been resolved and the program runs without a hitch and even saves the city money. But success has come with much trial and error, regrouping, careful planning, and lots of hard work. A testament to the site’s success is evidenced by the city’s own Leaf and Brush Committee, which once convened on a regular basis to discuss various impediments related to collection and composting issues. The committee – comprised of city staff, elected officials, residents, and related industry professionals – hasn’t had to meet in almost ten years. With yard waste collection, leaf composting and brush grinding so finetuned, there simply hasn’t been anything to talk about.
ESTABLISHED, UNIQUE COMMUNITY
The city of Ladue was established in 1936, has an approximate population of 8,413, and is located about six miles from downtown St. Louis. It occupies a land area of 8.6 square miles. No major hardware, electronics or department store chain stores exist in the city, and the banks, pharmacy, restaurants, clothing stores and real estate offices are all independently owned. In the small business district, one will also find gift shops, boutiques, gourmet delis, and a true American endangered specie, the independently-owned hardware store. Ladue has four country clubs with golf courses, seven places of worship, and more private schools (six), than public (five).
While there is some business activity, the city is mostly residential, with approximately 3,345 homes. Not all of them are mansions, but based on 2000 Census data, the median house value is $585,300 and median household income is $141,720, both substantially higher than St. Louis County and Midwestern averages. Those numbers are most likely much higher now, and as an example of the community’s affluence, in 2003, a total of 12 new homes were built at an average cost of $1,620,800. With an abundance of deciduous trees, large sprawling landscaped properties, a friendly, neighborly feel, and relative seclusion from the hustle and bustle of metropolitan St. Louis, Ladue would seem an idyllic place to live if one could afford a home there. So what the heck’s an outdoor, open windrow compost facility doing smack dab in the center of such a posh bedroom community, and how has it succeeded?
In the early seventies, when local governments were becoming more conscious of the environment, Ladue established its Leaf and Brush Committee. One of the committee’s first projects was to rent a Leaf Destructor to destroy leaves rather than burning them, as had been the most common method of leaf disposal at the time. After a year or so, the County of St. Louis shut it down due to the amount of pollution it caused. The committee began looking for more environmentally-friendly options for handling its leaves and brush.
In 1978, Ladue residents were polled on methods of collection and disposal they’d like to see, and more than 77 percent indicated a preference for leaf and brush collection, as well as composting and mulching, rather than burning or landfilling. There was only one piece of empty property in the city, owned by Union Electric, which had the potential for use as a composting site. After several rounds of negotiation, the 14.4 acre parcel of land was sold to Ladue, and preparation began in 1988. The facility officially opened in 1989, and in 1990, several acres were improved with an all-weather pad. The balance was left undeveloped as a treed buffer zone.
Despite a few initial challenges, the site worked well, and was already gaining a good reputation. A visit to the facility by St. Louis County Director of Transportation and Environmental Policy, Lee Brotherton, inspired him to write: “It is particularly notable that the city of Ladue has taken such a visionary approach to the program of municipal yard waste.” And visiting Missouri State Representative James Barnes had this to say about the operation: “It was interesting to see what is truly the Cadillac of compost sites in and about the St. Louis Metropolitan area.”
FROM GOOD IDEA TO STATE LAW
Ladue’s leaf and brush program went from being simply a good idea, to a state law. With the passage of Senate Bill 530, yard waste was banned from the landfill in the state of Missouri beginning January 1, 1992. While Ladue had a good head start, the legislation did create some challenges. Residents no longer had the option of disposing yard wastes with their household garbage, and the volume of leaves and brush material collected and delivered to the facility quickly grew by one third. An extremely wet season combined with the volume increase led to stockpiling of leaves, and odors.
An odor suppressant was employed, and a Scarab was purchased to aerate windrows. The site was also expanded by about a third, and a retention pond was built. Despite the efforts, odors persisted, and a multitude of complaints was received. The Leaf and Brush Committee explored alternative options to the program, including direct transport in Ladue vehicles to another facility, and curbside collection and transport to another facility by an independent contractor. These options proved to be substantially more costly to residents – with some alternatives three times the expense – than Ladue performing collection and processing itself. The committee chose to attempt to rectify odor and capacity challenges at the facility by consulting academic, scientific and industry experts.
In 1994, Organic Recycling, Inc. (ORI), a Tappan, New York-based company specializing in managing sensitive large-scale composting operations and remediating challenged facilities, was brought in. The decision was made after the mayor at the time, Edith Spink, Dennis Bible, and several members of Ladue’s Leaf and Brush Committee visited a private composting site in Illinois that ORI had been hired to remediate. The facility in Illinois had a history of severe odor problems, and was on the brink of being shutdown by enraged neighbors. ORI took over management for one year, in which time odors were successfully eliminated, and a revised process management protocol was implemented to prevent further problems.
The same year ORI was hired by Ladue, it was also under contract with the County of St. Louis to review and make recommendations for improvement on all existing municipal composting operations in the county. ORI’s study found Ladue had the best facility, most adequate equipment, and highest quality end-product, while other sites had more challenges to address related to odor, capacity, contamination, inadequate personnel and equipment resources, and the ability to complete composting and remove material prior to delivery of the following season’s leaves as well. And while Ladue did face odor and capacity challenges prior to contracting ORI, the program’s existing resources were sufficient enough to provide a foundation for the company to quickly transform the facility into an efficient, odor-free operation.
MONITORING PROTOCOL
A monitoring protocol was developed and Ladue staff was trained to compile daily data on temperature, moisture, porosity, pH and odors. ORI reviewed the monitoring reports and made processing recommendations, such as more or less frequent turning, addition of moisture, and reduction of windrow sizes, based on the biological parameters of the composting substrate. Since the feedstock arrives uncontaminated and in pure leaf form, no pregrinding is done prior to incorporating material into windrows, nor is screening required after composting is achieved. Particle size is reduced quickly through a combination of controlled, intense biological activity (temperature range averages are 130°-140°F during peak composting cycles) and the shredding action of the Scarab. Each windrow is aerated approximately 30 times during peak periods of the composting cycle.
As operational challenges were resolved, the finished product improved as well. Compost produced at the facility is not only available to residents, but is used throughout Ladue in Public Works projects, in such applications as the city’s Rodes Park, landscaping at City Hall, on State of Missouri right-of-ways, and in a flower pot soil mix used to grow petunias along the main business district. Due to its high demand and primary use by residents as mulch, composted leaves do not go through a curing phase at the facility, but rather are removed immediately after composting. For applications requiring final stabilization, small volumes of product are cured off-site at the public works yard and other off-site locations.
Ladue also donates 600-800 cubic yards of compost per year to the Missouri Botanical Garden, one of the world’s leading botanical research and conservation institutions, which uses it throughout its 79-acre grounds on everything from Korean azaleas and cherry blossoms to boxwoods and conifers. Compost is applied as mulch or cured on-site prior to soil amending uses. Dr. Steven Cline, Director of the Garden’s Kemp Center for Home Gardening, helped Ladue initially establish composting operations and has remained an advisor and energetic supporter of the program.
As an added bonus, Ladue’s composting program has made good economic sense. When compared to alternative options available, the program has saved the city and residents more than $2.75 million since construction began in 1988. A recent audit of the city’s leaf and brush collection and composting and grinding services revealed an annual per household cost of just $65 for all combined services. Other options researched, such as residents contracting their own haulers, exceeded $300 per household annually. There are three keys to the savings. One is the fact that Ladue has been able to utilize existing labor resources to operate the facility, as no additional staff was hired to work at the compost site. Another is the avoided transportation costs, as the nearest compost facility outside of Ladue is at least an hour roundtrip away. By composting within the city, Ladue is passing on savings to residents of 200 percent or more. The third is the management protocol ORI has established, which focuses on a proactive, preventive approach to processing. In composting, preventing potential problems is one-third the cost of solving them after they occur. Hence, the preventive measures, that are now part of Ladue’s day-to-day operations, translate into substantially reduced costs.
BASIC STRATEGY FOR SUCCESS
Ladue’s overall composting program success can be attributed to numerous factors. The basic strategy has been to keep the windrows aerobic at all times, compost material as quickly as possible by ensuring a peak rate of decomposition, and remove it to finished markets as quickly as possible, to eliminate or minimize the need for stockpiling. Windrows are kept aerobic through a strict regime of monitoring and use of both the Scarab and front-end loader for aeration. During peak composting, windrows are turned 3-5 times a week with the Scarab, and once a week with the loader. Fast turnaround also means the same facility can be used for composting in the winter and spring, and brush chipping in the summer and fall. There is insufficient acreage to do both at the same time.
Ladue collects and receives approximately 29, 000 cubic yards of brush per year. Like leaves, brush is collected curbside, transported to the facility, and ground to one inch minus with a Williams Patent Crusher & Pulverizer Co. electric hammermill. To ensure minimal impact to neighbors, grinding is done behind a specially engineered sound wall and within designated daytime hours least likely to disturb residents. A curbside program utilizing portable chippers once used prior to purchase of the hammermill was also discontinued in consideration of residential noise abatement. Brush chips are formed into windrows and aerated with the Scarab until temperature monitoring indicates putrescibles have been degraded. Weed seeds are also destroyed during the process. Brush chips are given to residents, who remove them at a rate as equally fast as composted leaves.
The biological essence of the composting process, which was overlooked prior to ORI’s engagement, mandates the diligent monitoring of windrow moisture/nutrient/oxygen properties, or mass balance. If monitoring and any subsequent corrective action required is not performed immediately, problems can develop in rapid succession, especially in such a high-volume, limited-capacity facility such as Ladue’s. Site staff use a Reotemp thermometer with a three-foot probe, and a Kelway Soil pH and Moisture Meter to take readings. These instruments alone have been sufficient enough to monitor the process and provide ORI with the data necessary to develop a processing protocol and make adjustments in turning and watering schedules as required. Oxygen levels are assessed indirectly by temperature data and odor characteristics. When ORI is not on-site, facility operators send data to them via fax. In addition to ongoing hands-on management and site visits, ORI is available 24 hours a day during the composting season to troubleshoot any possible challenges over the phone.
Two dedicated employees operate the site year-round, one who has been there since the facility first opened, and the other for more than eight years. The experience they now possess is an asset to the program, and ensures windrows are monitored and aerated properly, equipment is taken care of and ready on demand, and finished product quality remains high. On and off-site odor checks are done on a regular basis, the site pad is kept clean and monitored for leachate, and the retention pond is lime stabilized and pumped out frequently. Dennis Bible, among his many other responsibilities as the department head of public works, remains actively involved in the program on a daily basis and ensures best management practices are employed at all times. He also keeps in close contact with facility neighbors, which provides ongoing feedback with regard to the site’s operations and makes them feel like they’re part of the loop. And of course, they are.
RESIDENTS GET CREDIT
Credit for the success of the program also has to be attributed to the Ladue residents themselves, who adhere to strict collection guidelines, help the material turnaround quickly by using it on their home landscape projects, and perhaps most importantly, gave the city the benefit of the doubt and allowed them the time to resolve facility challenges in the earlier years of its development. The city returns the favor by providing free collection services for leaves, brush and Christmas trees, free compost and mulch, and facility process control which minimizes the impact of the operation to a degree that neighbors now barely know it’s there.
In these days where NIMBY rules, and irate neighbors lobby to shut down composting operations, it’s encouraging to know an open, outdoor windrow facility can remain in good public favor while operating full-scale within that community. While Ladue may have some resource advantages over similar municipal programs, the bottom line is that careful planning and meticulous management have ensured the facility’s success, and this attention to detail could be easily duplicated at any public facility, even in the most sensitive of locations.
Though true Ladue has a model program, there’s really nothing high-tech or sophisticated about it. Through foresight, hard-work, patience, and lots of cooperation between all parties involved, including city legislators, staff, residents and consultants, a successful composting operation was born and thrives in one of the most delicate locations possible. And after more than a decade since it first opened, the compliments keep coming. “You certainly have developed and perfected an efficient composting system for the city of Ladue,” Greg Hayes, Acting Commissioner of Forestry for St. Louis, wrote to Dennis Bible in March of 2004. “Perfected?” Maybe. If it wasn’t for that darn gum wrapper.
Rich Flammer is a freelance writer and composting consultant living and working in San Diego, California. He can be reached at (619) 758-0726.


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