, f?-mtw= JQJLJ‘ [QL REACHING DIVERSION GOALS

MILITARY BASES STEP UP RECYCLIHG PROJECTS

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From California to Massachusetts, from Alaska to Cape Cod, enlisted personnel and officers participate in programs that recover all kinds of compostables and recyclables.

Molly Farvell

Food residuals from Otis Air Force Base are composted at Watts Family Farm (left). Affer three to six months, the materials are screened.

ERSONNEL at American mili- tary installations continue to ex- pand waste diversion programs to include woody materials as well as food residuals. Two bases plan to transform bioremediation P facilities into composting sites,

while another grinds C&D debris into chips for use as a bulking agent. At California’s Camp Pendleton - the nation’s largest Ma- rine Corps facility - curbside collected re- cyclables include cardboard along with glass, plastics and cans. At some military fa- cilities, arrangements have been made with local recycling companies or farms to ad- vance projects.

For example, a Cape Cod, Massachusetts turkey farmer is collaborating with state and federal officials to compost food residu- als from Otis Air Force Base. Peter Watts, owner of Watts Family Farm, grows 1,000 turkeys on his 29-acre farm in Sandwich, Massachusetts. He is composting the turkey manure, offal and feathers with sev- eral other feedstocks, including food resid- uals, cardboard and soiled paper from the base, as well as seaweed from the town of Yarmouth’s beaches.

The 2,200-acre Air Force base is located next door to the farm. Watts had been com- posting small amounts of off site materials for approximately five years, under a condi- tional exemption for agricultural opera- tions. He was approached about composting the base’s food residuals by Maarten van de Kamp, a compost specialist for the Mas- sachusetts Department of Food and Agri-

culture and Sumner Martinson, director of compost programs for the Massachusetts Department of Environmental Protection.

The goal was to develop a “compost part- nership” between the base and the farm that could be a model for southeastern Mas- sachusetts, explains Bob Cannon, an envi- ronmental protection specialist a t Otis. “It makes good economic sense to minimize the amount of material we send to an incinera- tor in Rochester, Massachusetts. We decid- ed to start small and collect material from the galley dining facility for active duty per- sonnel first, then the Otis Golf Course facil- ity that has a small snack bar that becomes fully operational in June.” He estimates that the golf course facility will generate five tons a year of food and paper residuals.

Watts started composting the dining fa- cility’s food residuals in January. The farm uses a dump truck to collect compostables three times a week from the galley. Watts expects to collect about 50 tons a year of food residuals, cardboard and paper nap- kins. Kitchen workers put food scraps into cardboard boxes and dump them into 85- gallon wheeled containers kept in the back of the galley. The containers are wheeled out of the galley when full and loaded onto a truck. Cannon recently purchased a portable lift so that Watts and his employ- ees don’t have to manually lift the contain- ers, which can weigh hundreds of pounds when full. The container is placed on the back of the lift and raised four to five feet. Watts estimates that he collects 800 t o 1,000 pounds each trip.

BIOCYCLE JULY 1998 51

The next step, says Cannon, is to divert A self- welled turner aerates food leftovers from the 635 housing units on Q wingow at the Air Force the base (2,200 residents). “We are looking at ~ ~ ~ a ~ ~ f i ~ ~ ~ ~ ~ $ ~ ~ ~ n g s f providing the housing units with individual about , f200 of backyard composting units or setting up a collection point in each neighborhood,” he says. “Trash is currently being collected twice a week for residents, but with food waste composting, we think that we can re-

Watts has brought in 5,000 cubic yards (cy) of wood chips from landscapers and land clearers for use as a bulking agent. “We have a lot of scrub pine on the Cape,” he explains.

compost.

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duce trash collection to once a week.” Besides arranging with a nearby farmer to COmDOSt food residualifrom “We keep the firewood, and the pine is

chipped for composting.”

its dining facility, Feedstocks are composted on a seven-acre pad in outdoor windrows measuring ap- proximately 16 feet wide, 12 feet high and 75 to 100 yards long. When first formed, the windrows are turned two times a week with a front-end loader, then once a week, every two weeks and then once a month. The ma- terials are composted for three to six months until stable and then screened. The farm is now producing 5,000 cylyear of compost, which is sold in bulk for $ 2 5 1 ~ ~ .

Otis Air Force Base has been doing curb- side recycling for five years. Tin, aluminum cans, plastic bottles, newspaper and glass are collected once a week. Cannop estimates that the recycling program takes 56 tons of materials out of the waste stream annually. The base also recycles batteries, cooking grease, lead shot from the indoor shooting range, used oil, cleaning solvent, tires, white paper and brass through its industrial pro- gram. Cannon estimates that 69 tons of in- dustrial recyclables are diverted from the landfill annually. Five base personnel won the White House Closing the Circle Award in 1997 for “recognition of achievement in federal acquisition, recycling and waste and pollution prevention.”

CALIFORNIA‘S CAMP PENDLETON EXPANDS CURBSIDE COLLECTION

Camp Pendleton is located 45 minutes from the Mexican border, between the cities of San Clemente and Oceanside, California. The base has 125,000 acres, making it the largest Marine Corps facility in the country. It has a daytime population of 100,000, in- cluding 37,000 active duty personnel, 15,000 civilian employees and contractors, as well as military retirees and residents of neigh- boring cities who come to shop and use the base’s other amenities.

There are more than 6,000 homes for mil- itary families on the base. Pendleton collects recyclables from the housing areas every other week through its own curbside pro- gram. The residential collection includes col- ored and clear PET and HDPE plastics (#1 and #2), metal food cans and aerosol cans, glass beverage containers and jars, and newspapers. “A lot of people are constantly moving, so we also collect a lot of corrugated cardboard from moving boxes,” says Charles Bradshaw, Pendleton’s recycling program manager. Mattresses, reusable furniture

Otis Air Force Base collects 56 tons of recyclables at curbside. and appliances are collected through sepa-

rate pickups. The base uses both curbside collection trucks and trailers pulled behind a pickup truck to collect materials.

Recyclables also are received and collect- ed from the base’s military units and civil- ian managed offices, including administra- tive offices, supply warehouses and recreation and lodging facilities. A recycling facility on the base processes, packages and bales recyclables and solicits bids for the materials when adequate quantities have accumulated. Bradshaw reports that the amount of recyclables collected has in- creased from 3,848 tons in fiscal 1995 to 5,718 tons in fiscal 1997.

Camp Pendleton’s Environmental Securi- ty Department is studying the feasibility of collecting and composting organics, includ- ing food residuals, yard trimmings and biosolids. Mike Pinsoneault, the depart- ment’s solid waste and storage tank branch head, says a consultant has been hired to identify all of the compostable waste streams as well as potential customers for compost products. “Pre and postconsumer food waste could be collected from the base’s two commissaries, eight mess halls and hos- pital,” says Pinsoneault. “Yard trimmings could be collected from our landscaping op- erations as well as base contractors, and biosolids from the base’s eight wastewater treatment plant facilities.’’ Food residuals and yard trimmings currently are brought to the base’s Las Pulgas landfill.

Pinsoneault says that the organics could be composted at an existing bioremediation facility with some simple modifications. “The facility consists of two one-half acre concrete treatment pads which can be mod- ified for use as a static pile composting sys- tem,” he explains. There are an additional four and a half acres that can be used for other composting technologies such as ver- micomposting, according to the consultant’s findings.” He expects the bioremediation program to be completed by next spring,

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52 BIOCYCLE JULY 1998

tive combat training range for pilots and sends out personnel to collect the materials -

making the site available for composting. “The decision whether to construct and op- erate a composting facility will depend on the results of the consultant’s study,” he notes, adding that the base currently has a landfill diversion rate of 33 percent and ex- pects to meet the Department of Defense goal of 50 percent by the year 2000.

PUSHING THE ENVELOPE AT LUKE AIR FORCE BASE

Approximately 9,000 people live and work at Luke Air Force Base near Phoenix, Ari- zona. Unusual materials are recycled there, including plastic beads used in painting metal parts and brass shell casings.

In blast painting, small plastic beads are shot through a gun to strip the paint off met- al parts. The blasting is done in enclosed booths, and blast media can be reused sev- eral times. The booth has a floor that vacu- ums up the beads and paint chips through vents after they are blasted onto a piece of equipment. The vacuum pulls the media and paint chips into the system and into a bag house. The heavier chips fall to the bot- tom and the beads are reused. Once the beads have expended their useful life, the blast media and smaller paint chips are col- lected in containers and taken to a recycler. The recycler remelts the plastic, which is made into bathroom fixtures such as show- er stalls, sinks and countertops.

The base also has a large scrap metal pro- gram, collecting approximately 2,500 tons in 1997. A civil engineering squadron which provides plumbing, electric, heat, ventila- tion and road repairs has a metal shop. All of the scrap metal is collected from the shop and taken to the Defense Reutilization and Marketing Office (DRMO), which is respon- sible for disposing of government excess.

The base collects and recycles brass shell casings from rifle ranges, aluminum tips from target practice, aluminum and steel from practice bombs and metal from leaking underground storage tanks. Luke has an ac-

after practices. The shell casings are taken to the DRMO and sold as scrap brass. Virgil Approximately Martinez, chief of pollution pievention pro- grams, estimates that the base has sold more than 50 tons ofbrass casings. The base

1,200 tons of COmpOSt are

collects and recycles the fins-on dummy bombs. which are made of aluminum and produced each year

i t the Air For&

Colorado Springs.

steel, and the tips of practice bullets, which are made of aluminum. Luke is under man- date to pull out and replace leaking under- ground storage tanks. Once the tanks are

Wooden pallets and skids are sold to var- ious contractors. (‘A lot of them are refur- bished because there is a strong market for recycled pallets, and the rest are resold to pallet recyclers who have tub grinders and grind them into mulch,” says Martinez. “We recycle almost anything that has a potential value, including CD discs and ink jet containers for ink jet printers,” says Martinez. “We can recycle machine parts as long as they are not classified. We recy- cle computers after cannibalization, as well as furniture and white goods that the DRMO cannot refurbish and resell.” He notes that Luke is one of the few bases in the U.S. that has a contract for aircraft tires; most tires are ground up and used as fuel for cement kilns. Auto tires from the base are ground up and used as top cov- er for landfills.

Academy in decommissioned, the metal is recycled.

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BIOCYCLE JULY 1998 53

A blower aerates composting materials in an outdoor bin at Elmendorf Air Force Base in Anchorage, Alaska.

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Luke Air Force Base collects and recycles brass shell casings from rifle ranges, aluminum tips from target practice, aluminum and steel from practice bombs and metal from leaking underground storage tanks.

More traditional recyclables are collected curbside once a week in a commingled con- tainer from approximately 900 military housing units, as well as dormitories, cafete- rias and a base commissary. Recyclables are also collected through ancillary programs from the base’s bowling alley, movie theater, Burger King restaurant and gas station.

Luke experimented with composting MSW and biosolids from the treatment plant in a rotating drum. Only one in four trials was successful. The base is looking into other composting methods.

AIR FORCE ACADEMY SHIFTS FROM OUTDOOR TO IN-VESSEL COMPOSTING

The Air Force Academy in Colorado Springs, Colorado has been composting or- ganics since 1992. It started with a five- acre outdoor windrow system and expand- ed to seven acres in 1995. The Academy composts 10,000 cy a year of organics. Two- thirds of the material are yard trimmings from landscaping activities (the Academy is on 19,000 acres), parade grounds, golf course, athletic fields and 1,200 family housing units. The remainder is manure from the 120-horse stable and shredded wood from trees and pallets.

Approximately 1,200 tons of compost are produced each year. Most is used in-house, although 10 to 20 percent is designated for the Colorado Mountain Reclamation Fund, a nonprofit organization established through a grant from the Governor’s office to reclaim mining areas. The Academy has had difficulty transporting the compost to the quarries but is working with the Fort Carson Army Installation. “They have the personnel and troops available to do large pick-ups and haul it 10 to 15 miles to the quarry,” notes Diana Dean, the Academy’s chief of environmental compliance and pol- lution prevention.

The composting operation is run by a full- time operator, John Teeter, and a recycling manager. The facility’s equipment includes a front-end loader, a CMI Maxigrind and a

windrow turner. All of the compost passes through a trommel screen. The finer mate- rials are used as a soil amendment for shrub plantings and tree beds. The coarser mate- rial is used for erosion control. “The soils here are not good, and we have to do a lot of erosion control,” notes Dean.

The Academy installed a Wright Environ- mental in-vessel composting system in April, 1998 that Dean plans to use for food residuals. “I definitely think that it will hap- pen by 1999,” she says. ‘(We want to take the rest of the year to get our personnel familiar with the machinery. We want to install pulper units to dewater the food residuals to reduce volumes, as well as reduce pest and leachate problems.” The Academy has sev- eral different dining areas, but all 4,000 cadets eat three daily meals in the main din- ing facility. Dean says the Academy at- tempted to compost food from the main din- ing room in outdoor windrows in a 1994 trial, but experienced logistical and pest problems. She also hopes to expand into composting biosolids from the Academy’s wastewater treatment plant in the in-vessel system. “First we’ll need state approval be- cause we are currently operating under a pi- lot project designation from the state and county,” she adds.

The Academy’s recycling program started as a dropoff program in 1994 and has ex- panded into curbside, hallway and deskside collection programs. Its hazardous waste recycling program for paint and aerosol cans, oils, batteries and solvents won the White House Closing the Circle Award in 1997 and the Air Force Environmental Compliance Award in 1995. “We started out just disposing of paint, then began bulking paint for recycling, and now crush paint and aerosol cans for recycling,” says Dean. There is also a household hazardous waste drop and swap program that operates once a week year-round.

27 PERCENT AND CLIMBING AT ALASKA’S ELMENDORF BASE

Located on 6,000 acres in Anchorage, Alaska, Elmendorf Air Force Base has con- ducted pilot composting programs that have used grass clippings, horse manure, food residuals and waste paper as feed- stocks. For its food trials in small enclosed bins from June through November, 1997, food residuals were collected at the base’s Officers’ Club Dining Facility. The bins were originally intended for vermicompost- ing, says Cheryl Paige, Elmendorfs pollu- tion prevention coordinator. “We were be- ing careful about how much food waste we put in the trays, but it still got too hot and was melting the earthworms.”

Initially, shredded paper, shredded co- conut husks and wood chips were added for aeration and as carbon sources, but Paige switched t o using just shredded paper.

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Scrap wood that could be recycled or composted at Alaska’s Elmendorf Air Force Base comes from land clearing, C&D debris, wooden munitions boxes and pallets.

“Shredded paper is great with food waste be- cause it is fluffy enough to be absorbent when stirred in,” she says. “It’s also hard for recycling workers to deal with, so they’re glad to have us use it. The squadron shreds paper to one-sixteenth of an inch or less and we pick it up from them in bags.”

The base is also composting grass clip- pings and horse manure in outdoor bays made of plywood, each measuring 10 by 12 feet. Paige estimates that 120 yards of horse manure and 40 yards of yard trimmings can be collected from the base each summer. The manure comes from tKe 34 horses a t the base’s stables.

The Air Force has a goal of reducing waste by 50 percent, and Elmendorf has reached 27 percent. “We are still trying to reach the 50 percent goal and believe that we can do that with composting,” says Paige. To achieve that, Paige has request- ed that the Air Force convert a clay pad a t a bioremediation site on Elmendorf into an outdoor composting facility. The bioreme- diation facility was built several years ago to clean contaminated soil on the base and is completing work on the last pile of soil. She states that with a larger facility, the base could compost 4,200 tons of organics a year, including 1,240 tons of wood, 2,150 tons of paper, 785 tons of food and 125 tons of manure. Composting these materials in- stead of landfilling them would save the base more than $175,000 in avoided land- fill tip fees and fertilizer costs. In 1997, the base purchased 60 tons of commercial fer- tilizer and uses up to 60,000 cubic yards of topsoil annually.

Markets don’t currently exist for the base’s scrap wood, so Paige is planning to also incorporate it into the compost mixture. The scrap wood comes from a variety of sources, including land clearing, C&D, wood- en munitions boxes and pallets. Paige notes that the C&D and munitions boxes amount to 1,550 tonslyear, which is 19 percent of the waste stream. The base is required by regu- lation to reuse pallets if they are still ser- viceable. Most of the C&D debris is of 1940s World War I1 vintage. “The base is a historic district and many of the buildings have his- toric or architectural significance, so we have to remodel and repair the buildings instead of tearing them down,” says Paige. The base also has a large amount of wooden munitions boxes left behind by the 3rd Wing F-15 fight- ers and surveillance jets it deploys around the world.

Previously, if scrap wood couldn’t be resold by the DRMO, it would be hauled to the landfill. Since last winter, the base has been stockpiling C&D debris, pallets and munitions boxes. The wood will be shredded into one by three inch chips with a grinder and used as a bulking agent.

Elmendorf also has an extensive recy- cling program. Paige was originally hired in 1992 to implement recycling and has set up curbside, dropoff and office pro- grams. Approximately 11,000 people occu- py the base during the day, including 7,000 active duty personnel, 2,000 family mem- bers and 2,000 civilians. There are 1,800 housing units on the base. Every household is given two 16-gallon blue recycling bins: one for paper, cardboard and cereal boxes, and the second for metal cans, plastic jugs and glass jars. The bins are collected weekly. Elmendorf bought the Air Force’s first curbside recycling vehicle from the GSA in February, 1996, which Paige says costs $50,000 less than hauling the recy- clables privately. ‘‘I% takes eight hours/ week versus three days the old way,” she says. The side-loading truck has six boxes on the passenger side. When the boxes are full, they are lifted into six bays on top that hold plastic milk jugs, glass bottles, tin and aluminum cans, mixed paper, cardboard and newspaper.

WHITEMAN AIR FORCE BASE Located in central Missouri, Whiteman

Air Force Base has 10,000 active duty and civilian employees. Each week, the recy- cling program picks up curbside materials source separated in four-section self-con- tainerized cans at military housing. Yard trimmings are picked up weekly from April through November. There also is a site open 24 hours a day for dropoff of recy- clables, including yard trimmings. Five

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A sifter takes out large wood pieces left after composting at Whiteman Air Force Base in central Missouri (above). Bins store the finished product after processing in an in-

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56 BIOCYCLE JULY 1998

two-yard bins are scattered in central locations between buildings for collection of bottles, cans, cardboard, mixed paper and bond paper. To prevent contamination, materials are source separated before being set out, the collection con- tractor ensures separation as required, and the base gives a final check. “Between those three looks at it, we get some really good product,” says Steve Brockman, resource recov- ery and recycling program manager. “That’s what it takes.” The only contamination is a small amount of plastic in yard trimmings, which is screened out.

The recycling program’s annual collection volume is 450 tons of ferrous metals, 25 tons of nonferrous metals, 20 tons of steel and tin cans, 12 tons of aluminum cans, 220 tons of OCC, 50 tons of bond paper, 85 tons of newspaper, 150 tons of mixed oftice paper, 28 tons of plastic milk jugs and PET, 60 tons of used tires, 14 tons of lead acid batteries and 28 tons of white goods. Recently, the base began pulverizing glass into glasphalt.

Brockman estimates the recycling program will account for $40,000 in revenue and cost avoidance in 1998. At least three bids are required for the sale of materials. The vendor who faxes in the highest is awarded the package and takes on responsibility for transportation. Brockman says he has good success with putting multiple materials in the same bid package.

The Ag-Renu in-vessel technology licensed to Spec- traserve of Kearny, New Jersey is used to compost yard trimmings and leaves with wood pallets and crates. (See “In- stitutional Experiences with Composting Containers,’’ February, 1997.) Purchasing a Morbark tub grinder last year has cut labor costs by almost two-thirds, notes Brock- man, who now spends about 80 minuteslweek on grinding. The process also produces 75 tonq of mulch annually. Ap- proximately 500 tons of finished compost were used for base and community projects in 1997, about half of the antici- pated amount. Compost production was less than expected in 1997 because of a computer breakdown and a halt in op- eration to build concrete containers for feedstock and fin- ished compost Previously, yard trimmings had been kept in loose piles outside; now the material is roofed in 20-by-20- foot bins installed in June last year.

Barring breakdowns, Brockman expects to double compost production by operating throughout 1998. If that goal is met, he plans to market locally to nurseries in bulk orders of 40 cu- bic yards or more. He is testing to ensure the compost meets standardized levels for nitrogen, pH and organic matter.

Last fall, “when newspaper was virtually worthless,” Brockman shredded and composted it with excellent results. However, now that the market has recovered, he is baling and selling it for recycling. Although he doesn’t expect his budget to allow for another in-vessel system to compost card- board, biosolids and contaminated soil in the near future, Brockman is looking into small units that could handle food residuals from the base’s residences and dining facilities. “It’s 22 percent of the recyclable waste stream,” he notes. “We need to jump on this opportunity.”

Angie Barnum, environmental awareness program man- ager at Whiteman, has joined forces with Brockman to edu- cate the base and local communities about the addition of composting to the recycling program and expand participa- tion. Barnum’s efforts include attracting media coverage, de- veloping a “HOW TO” recycling video, and designing informa- tional brochures and newsletters. She also produced mobile exhibit displays and was asked by the Environmental Pro- tection Agency to discuss the base’s composting operation. “It’s important to educate the surrounding communities about our commitment to environmental stewardship,” she says. “Building positive relationships between the Air Force and the public leads to lasting partnerships, strengthens the bond for additional educational opportunities, and ultimate- ly increases recycling participation.”

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/

Getting To Your Feeds Taking the time with the composted will

including odor

to get faml(ar

Robert Rynk

E DREAM composting facility would have any feedstock it T" needed to make the recipe per-

fect in terms of moisture content, carbon:nitrogen (C:N) ratio, pile structure and so on. In reality, how- ever, most compost operators need to play with the hand (feedstocks) they are dealt. The trick, therefore, is to understand the characteristics of those feedstocks to optimize the recipe and mix, thus giving the

composting process the best chance of succeeding.

Getting the right mix also goes a long way toward avoiding odors. Based on my observations at com- posting sites, the fundamental prob- lems of many odor situations relate to feedstocks - not with the pro- cessing, engineering or handling. Odor treatment is often necessary to recover from poor selection of feed- stocks or site-related problems.

When mixing nitrogenous feedstocks such as seafood residuals (above) with carbon sources, operators need to determine not only how much carbon to add but also how much will be available during the composting process.

In the composting world, we often talk about the art and the science of managing the process. While de- veloping good compost recipes is certainly an art, we have the tools and the knowledge that have made it a science as well. Analyzing feed- stocks for such parameters a s moisture content, carbon and nitro- gen, bulk density and pH, provides critical data for putting the right mix together.

Moisture Content One of the most important feed-

stock characteristics - if not the most important - is moisture con- tent of the material. Moisture con- tent determines how easily the ma- ter ia l is handled, whether it composts faster or doesn't compost a t all, or becomes anaerobic. Also important is moisture absorption - not only how much water a feedstock has but how much water it can hold and still maintain some porosity.

Moisture is necessary for biologi- cal activity, providing a media for the biological and chemical reac- tions that take place, giving the mi- croorganisms that carry out those

JULY 1998