Whether municipal or private, solid waste management offers an ongoing challenge: conserving time and money.

By Joseph Lynn Tilton

No matter what the job, having the right tools and knowing how to use them is central to success, and the business of transfer stations is no different. Fortunately, thanks to ongoing improvement in tools, both private and public operations are finding solutions to their challenges while boosting productivity, lowering costs, and even helping landfills win a longer life.

New in Rhode Island

The new RIRRC transfer station has a translucent ceiling - a unique and energy-saving feature.

When it comes to solid waste, 2002 likely will be seen as a landmark year in Rhode Island. The General Assembly created the Rhode Island Resource Recovery Corporation (RIRRC) in 1974, which today handles 98% of the state's waste and is funded through fees for services, sale of recyclables, and royalties from its methane gas facility. "We have the first mandatory recycling program in the country," states Beth Bailey, senior account executive for the RDW Group Inc., a representative for RIRRC.

Bailey says the new transfer station, designed to handle 5,000 tpd of waste, began operation in April 2002, with 600 trash trucks and 200 other vehicles coming from as far as 39 mi. from the station and depositing 4,000 tpd in an operation that's open six days a week. "We have just seven employees at this time but expect to have 12 to 14 when we're at capacity.

"The primary reason for building this facility was safety," she continues. "Prior to erection of the transfer station, all vehicles were required to go to the working face of the landfill. Every time it got wet [rainfall averages 36 inches per year], two or three trucks would get stuck." Broken axles, punctured tires, and damaged transitions were frequent occurrences because of the unstable driving surface, she points out. Back then, dumping a typical load took 38 minutes.

With the new transfer station located just a mile from the landfill, the average truck dumps its load in 15 minutes because roads leading to the new facility are paved, trucks are tipping on a concrete floor, and loaders immediately push the load out of the way. "This makes it possible for haulers to make additional trips in a given day. There's a safer working environment because of the reduction of traffic as well as better traffic control," Bailey notes. All haulers who use this facility take training on how to enter and exit.

Incoming loads are sent to specific bays, with three designated for municipal waste, four for transfer trailer trucks, and three for rolloff trucks. With mandatory municipal recovery programs, municipal trucks are delivering only nonrecyclables. "A survey also showed that recoverable or commercial waste was arriving in rolloff trucks," Bailey says. "The transfer trailer trucks were coming from weigh stations where recyclables had been pulled. What gets checked at this operation is the waste brought in by smaller companies." RIRRC sends all waste destined for the landfill to the transfer station, with some specific exceptions. Raw fish waste is delivered directly to the working face of the landfill, only in the mornings and only by appointment. "Nor does this station handle leaf waste and yardwaste or construction-and-demolition waste material. Those are sent directly to other Rhode Island Resource Recovery facilities for processing and reuse," Bailey adds.

RIRRC moves compacted waste from the station to the landfill in a fleet of seven Volvos, making as many as 125 trips per day to the fill site. That waste is compacted again there, helping prolong the life of the 199-ac. site.

The transfer trucks stand on scales, so station employees know when it's time to send a vehicle to the landfill. "The scale also protects the corporation's vehicle warranties because they're never overloaded," Bailey points out. Three hydrants, as well as emergency fire suppression and washdown equipment, help the facility meet the state's fire safety codes. Piping and solid surfaces are heated to ensure ongoing operation despite temperature drops and snow loads. "We had 100 inches of snow in 1998, and we're in the hurricane track," she continues, "so we try to prepare for extreme weather conditions.

"The pipes in the transfer station are heat-traced; they have electric wires that run through them and heat them. The sprinkler system is dry. The washdown, fire hoses, toilets, et cetera are all heat-traced. The floor is heated using propane-fired infrared radiant heaters. They don't heat the air; they heat solid objects, including the floor and waste."

The loadout areas jut out from the main floor, maximizing tipping-floor space. "I'm told that this ‘overhanging' loading bay design is unique to transfer stations," Bailey says. "There is no dead space between the chutes." The ceiling has translucent paneling that allows natural light into the facility. With this operation there's little need for artificial lighting.

Another feature is the observation deck. "We aren't sure if this is unique, but we know that it's unusual," Bailey says. "The deck is glassed in except for the ceiling. It will be used primarily for tourist education. RIRRC hosts thousands of visitors, especially schoolchildren, each year." RIRRC has a special tour room in its materials recovery facility (MRF), where the audience hears a lecture, watches a video, and views MRF operations from the observation deck. Visitors then take a bus ride around the perimeter of the landfill, but it's unsafe to drive a school bus up to the working face, so they don't get to see much. "Now, instead of the bus ride, they will observe the trash operations up close in the transfer station," she adds.

Cook County Success

Baling, whether for waste or recyclables, has come to play a bigger and bigger role. A major baling pioneer has been the Solid Waste Agency of Northern Cook County, which serves 23 communities with more than 700,000 residents. Built in 1994 for $12 million, its Wheeling Township Transfer Station, located near the center of its collection area, is able to handle more than 1,500 tpd in an 82,000-ft.² building on 7 landscaped acres and has no visible waste. The tipping area can accommodate nine trucks and has a master control room with TV monitors and remote controls. In addition, visitors have a 535-ft. enclosed walkway.

The facility, which is cleaned daily, helps its densely populated member communities control loose litter, satisfy federal regulations, and give the landfill a longer life. Baling also makes it possible to transfer a greater payload because smaller, lower, lighter trailers can handle the baled waste and cost 20% less than conventional high-profile transfer trailers.

All this was possible thanks to Logemann Brothers Company in Milwaukee, WI. The transfer station there has three Logemann Model AT-445-B1-BG multimedia balers. "Each module features completely automatic baling, strapping, bale handling, and loading into covered aluminum transfer trailers. The balers can handle ferrous and nonferrous metals, paper, fiber, plastics, as well as unsorted materials," describes Robert Plichta, Logemann's general sales manager.

Walk on the Rural Side

Grapples are used to handle waste.

At the other end of the challenge is what's happening with transfer stations in largely rural areas. Across the continent in Alberta, Canada, the Vulcan County Waste Authority has five transfer stations that operate 24 hours, seven days a week. Each has a tipping area inside because of severe wind problems and to minimize rodent infestation. Located between Lethbridge and Calgary, this rural county, which abounds in grazing land, oil fields, and grain farming, is Alberta's second largest in terms of miles of developed road but has a population of only 6,500, so it needs to keep the operation as thrifty as possible.

Reports General Manager Dick Ellis, "We're diverting 70% to 75% for recycling, and also sorting out all the wood and metal, so only household waste goes to the landfill. A large share of what we receive is from individuals, so vehicle loads tend to be rather small." He states that the automated sites are part of a tax-operated system. "We don't charge users at the stations. Each site operator is there basically to ensure recyclables are not sent to the landfill." Nor are there scales at the stations–material is weighed as it enters the landfill.

Ellis says residents wanted a paid-for system. "When anyone was caught dumping on the sly, he was prosecuted, but dumped waste was a problem. Now the general feeling is that since they have to pay for it anyway, they might as well use it. Since we put these stations in two years ago, illegal dumping has been very minimal."

Going Rural Anywhere

Monroe County likes its collection system because of the simplicity and speed. When loaded, the bin rotates and drops the load into a waiting trailer.

There are other rural sites in North America facing similar challenges. Dennis Neufeldt, president of Haul-All Equipment Systems, explains the challenges facing rural counties. "We're looking at a greater and greater need for sorting materials. There's been a gradual tightening of materials that can be accepted in any one landfill. We've been designing transfer systems of self-dumping trailers for over 20 years, and one of the needs is to design a station so it can be utilized by all types and sizes of collection trucks, yet (users can) be in and out under 10 minutes."

Noting that the 40- to 50-yd., 10-gauge stainless or coated rotating bins eliminate the need for onsite loaders, Neufeldt explains that the bins have a convenient double lid system. "There's a drop chute for individuals with cars or pickup trucks. Those with collection vehicles can open the whole top hydraulically to dump their loads. When loaded, the bin rotates and drops the load into a waiting trailer."

Many sites don't need buildings to house them; footings suffice. But Monroe County, PA, has a building and a scale for weighing incoming and outgoing loads on-site, says Neufeldt. The building is strictly for recycling, not for waste transfer. Because the bins are not rotated, the county uses a loader. "The visiting vehicle driver doesn't need a site operator to help him enter or leave; all he has to do is punch in the codes for the material he's hauling, whether it's into the station or a bin load he's hauling out," he adds.

"Tourism is our big thing here," relates Dean DeLong, executive director for the Monroe County Municipal Waste Management Authority. "Resorts and ski slopes and the race track account for at least 60% of the income to the country, and their share of solid waste reaches 30% at times. For example, we had 150,000 people at the NASCAR races, which yielded 58 tons of trash in just one day." Countywide trash volume averages 300 tpd.

DeLong points out that the authority has a 100% recyclable rate; the seven transfer-storage stations, which are open to residents and commercial haulers, accept newspaper, junk-mail magazines, cans, cardboard, and plastic bottle containers. "Nothing else is permitted on the property; all is source-separated. We have 53-cubic-yard bins at the Blakely site, which is on the Pennsylvania-New Jersey border and about 2 miles from the New York line."

Each entering commercial vehicle uses a key that identifies it. The Fairbanks scale has a screen on which drivers enter their truck numbers and punch in the commodity code before dumping. "If it's a dual load, say half newspaper and half magazines, he dumps the first commodity, returns to the scale for another weigh, then dumps that other half and is back on the road. With a single commodity, site time is seven to 10 minutes, with 15 minutes common for split loads," explains DeLong. Onsite camera systems ensure better dumping compliance and better security, necessary because 100% of the products received at the site are marketable.

Current commodity ton prices in mid-2002 included $35 for newspaper, $29 for junk mail, and $22.50 for cardboard, with plastic bringing $0.09/lb. "Depending on the market, we're looking at $40,000 to $60,000 per month in receipts," DeLong says. He notes that Mondays and Tuesdays are heavy days because of weekend activities. Wednesdays normally are slow days, and holiday weekends can double the amount of material. "Anytime there's a Monday holiday, that Monday and Tuesday we're just swamped," he relates. Contract terms stipulate that haulers respond within an hour's notice of the need to empty any of the bins at this 24-hour-a-day operation.

The Commonwealth of Pennsylvania pays Monroe County a $7/ton stipend for all recycled material. "We're committed to the commonwealth until 2011, and last year we did 2,300 tons, with total MSW weighing 89,000 tons." Monroe County's waste management authority handles 85% of the solid waste generated in the county. Challenges include being geologically unsuited for landfills, with groundwater at the collection facility in Blakely at a scant 15 ft.

"We are the fastest-growing county in Pennsylvania and have been in the top two for the last 20 years," DeLong maintains. "We've experienced growth no other area of Pennsylvania has seen. We have school districts that have had to split because of a net gain of more than 1,000 students in a single year. We like this collection system because of its simplicity and speed."

Faster Machines, Denser Loads

The SSI Preload Compactor is programmed to build loads automatically.

"The single most important trend in the transfer station business is finding ways to increase payloads," declares Jim Jagou, vice president of sales for Harris Waste Management Group in Peachtree City, GA. From a perspective of 17 years in waste transfer, Jagou notes there are three methods for getting material into station containers: compaction, open-top trailers, and baling. "Manufacturers keep improving the efficiency of their machines. Hauls are getting longer and the cost of fuel continues to rise, which is why the overall trend is to find a way to get the lightest possible transportation equipment to accept the heaviest possible load."

Jagou says his firm does that by making it possible for users to preweigh loads and program the ideal weight for their receiving container. "Then once the compactor meets that load, it ejects the load into the receiving container. Also, we make balers for transfer purposes, with balers handling 80 to 90 tons per hour and TransPaks [preload compaction systems] up to 120 tons per hour. Larger bales mean fewer bales per transfer. Every time you move a bale, it costs you money; larger bales mean less handling expense and a lower cost of wire per ton."

Jagou states that balers exert 450 tons of force, and TransPaks exert up to 320 tons of force. "TransPaks vary the weight according to the receiving vehicle, while balers, generally of a fixed dimension, vary the load simply by the number of bales." He cites the example of New York City, where contractors use flatbeds, load up before crossing the scale, and then adjust the load. "Garbage weight can vary as much as 50% in the same dimension bale, and it's $85 per ton to ship to a landfill, so extracting wood, paper, other combustibles, and recyclables is a cost-avoidance feature that makes it worthwhile removing."

In Keller, TX, Richard Harris, managing director of the Recycling and Solid Waste Division of Sierra International Machinery, notes that balers can densify a load as much as 55-60 lb./ft.³ versus 12-15 lb. for a typical route truck. "This lowers transportation costs because baled waste can be stacked on a regular flatbed truck and shipped out one way. No [live] floor is needed, and transfer station operators don't have to buy anything because there are plenty of flatbed brokers around."

Transfer Station Wins the 100-Yard Dash

The St. Lucie County Solid Waste Facility; thanks to baling, landfills are able to achieve 1,600-2,00 lb./yd3

Although many areas face long hauls from the transfer station, there's one station operating near West Palm Beach in St. Lucie County, FL, that is a scant 100 yd. from the landfill. It's there to give the landfill a longer lease on life, get drivers on the road in 80% less time, and greatly reduce traffic on the landfill. Harris explains, "All garbage trucks pull over the scales, into a building, discharge on concrete, and the load is pushed onto a conveyor and loaded into a baler, letting the truck get back on the road in just six to eight minutes.

There's no waiting in line, no risk of getting stuck, no risk of damage to tires, clutches, or transmissions or lost time. They were looking to close that landfill this year, but with baling at the transfer station, that site can remain open another 20 or so years. Then, when the landfill closes, the station will continue to operate."

Thanks to baling, landfills are able to achieve 1,600-2,000 lb./yd.³ "With a baler, you get consistency, the same force exerted on the material each and every time, and there's no need to worry about the operator making a poor judgment. Also, baling is an inside operation, so wind, rain, or snow is not a problem. There's never any flying debris, and everything is kept neat and clean. Less daily cover is needed, so landfills are saving space and money."

Bales can be stacked three-high, reaching about 11.3 ft. before there's a need to cover. Harris adds that bales need but 2 in. of cover instead of the typical 6 in. for unbaled loads. "They've been baling in Europe for decades because of space concerns; we're bringing that technology to North America. Nobody wants to buy equipment, but they want solutions to the problem. Our big thing is giving them a free analysis of their transfer station or landfill and letting them see the comparison with other methods for handling waste. We do business by trying to solve problems."

Carl Winans, product manager for SSI Compaction Systems in Wilsonville, OR, has spent 40 years in the transportation industry. Whether the landfill is 100 yd. away or more than 100 mi., success also depends on each vehicle's maximizing its payload. He points out, "In North Carolina, the City of Durham's transfer station leads the nation in net highway loads by shipping 27-ton loads 85 miles to Virginia. Their truck tractors weigh about 14,500 pounds but come with 400-horsepower engines, so highway power is not a problem, while their aluminum closed-top trailers average just 10,500 pounds."

Stating that Durham's net loads are about 5 tons more than the industry average, he says the station is equipped with an SSI Preload Compactor, which has a large compaction chamber and can build the payload to precisely what the truck or trailer can legally haul. "The machine can build a compacted bale with the same density throughout its length, which distributes weight equally to the axles so the operator remains within the legal limit per axle as well as gross weight."

The machines are programmed to build the load automatically, which helps reduce the manpower needed at the station. Winans adds, "The normal bale time is eight to 10 minutes, or four to five loads per hour. Lightweight trailers are designed to unload on a hydraulic tipper at the landfill, which saves 3,000 pounds because they don't need a [live] floor. Every pound that you can save in trailer weight is potential payload revenue."

Whether rural or urban, regardless of content, having the right tools makes transferring waste easier than ever before. It also can turn a transfer station into a tourist site. Just ask Rhode Island.

Joseph Lynn Tilton is a frequent contributor to Forester Communications publications.

MSW - July/August 2002