Solid Waste Pilot Composting Project: Results and Lessons Learned The Marine Corps Base, Camp Lejeune Experience

Julie A. Shambaugh MPrineCorpsBaSe Camp Lejeune, North Carolina Penny M~scruo Parsons Engineering Science, Inc. Gary, North Cprolina

BACKGROUND Established in May 1941, MarineCorps Base, Camp Lejeune provides specialized training to prepare troops for amphibious and land combat operations. Today, Camp Lejeune occupies 153,000 acres with 14 miles of beach on the Atlantic Ocean. The Base operates and maintains more than 450 miles of fonds, 50 miles of railroads, seven wastewater treatmmt plants, five water treatment plants, a municipal solid waste landfill, and 6,800 buildings and facilities supporting 144,OOO Marines, Sailors, and their families. The Base buses the 2d Marine Division, the nucleus of the M h Corps East Coast force-in-readiness. Six Marine and two Navy C o d are stationed aboard @mp Lqeune. Also located within the boundaries of b m p Lejeune is the Marine Corps Air Station, New River. Camp Lejeune provides for its own solid waste disposal requirements. Approximately 300 tons of solid waste are generated each work day at Camp Lejeune. Composition of the waste is similar to that of a small city. The housing area refuse is similar to municipal waste collected from urban residential areas while the waste from the Base d u s t r i a l area is similar to the commercial and industrial waste generated inmany cities. The Base currently operates an unlined d t a r y landfill. A Resource Conservation and Recovery Act Subtitle D multicelled lined landfillfacility with leachate cdlection system at a 170-acre site locatedon-Base is expectedto be in operation by 1 January 1998. This new landfill will result io significant operating costs to Camp Lejeune, making alternate means of mpnnshq solid wppte o h more cost-effective. In M effort to reduce the volume of solid waste requiring landfilling and to make optimum use of yard wastes prohibited from landfill disposal, theBase requested approval from the North C a r o l i n a DivisionofSolid Waste Management to undertakeayear-longSolid Waste Pilot Composting Project. The state-permitted pilot project was approved in November 1994 and was initiated in 1995 upon delivery of windrow turning equipment.

PROJECT OVERVIEW Chnp Lejeune's solid waste reduction and recycling efforts are drivenby Department of Defense, Marine Corps, and State of North Carolina solid waste reduction and recycling goals and State of North Carolina landfill disposal prohibitioas. In developing the Base's solid waste management plan, a solid waste sorting, sampling, and analysis exercise was conducted io the fall of 1993 at the sanitary landfill. The characterization analysis included

waste from households, offices, and commercial and industrial activities. Results of thesampling analysis indicated that compostable materials such as paper products (37 percent), food wastes (15 percent), and yard wastes (three percent) comprised approximately 50 percent of Camp Lejeune's landfilled solid waste stream. In contrast, the compostable fraction of the United States' landfilled solid waste stream totaled 41 percentin 1994 and consisted of 30 percent paper products, three percent food waste, and eight percent yard waste.

Based on this analysis, it was estimated that as much as 8,OOO tons, about 30 percent by weight, of the materials landfilledat Camp Lejeune could successfblly be collected for composting given realistic collection rates, projected capture rates, and contamination levels. Camp Lejeune officials decided to undertake a year-long solid waste pild compost project as a means of gaining experience upon which to evaluate the implementation of fulla

xale facility

Tbe_State of North Carolina Solid Waste Section issued a permit in November 1994 to Camp Lejeune for a Municipal Solid Waste Compost Demonstration Project to be operated over a 12-month period at the Base’s sanitary landfill; the project was initiated in October 1995. By conducting this project, G m p Lejeune has gained

the necesmy experieoce to &ermine the exto which long-term municipal solid waste composting CM be feasibly cooducted aboard h. Tbe project m t e d various mixes of compostoble maiwiah yard wastes, food wpstes, pulverized dsbrdded paper, chipped wood waste, corrugated cardboard, horse mpnure, wastewater and woter plantsludges, and wood dr. F W compostbps beea tested using the Toxicity CharacteristicLeaching Procedure. No limitmg pcvpmebn h v e beep identified and the hished compost mptefipl has successfully been wed in borticulturd rpplicotioos d to reptore topsoil depleted, sandy lonm soils.

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Objectives of the stabpermitted pilot solid waste compost demonstration project+re to: Evaluate cornposting various mixes of available material generatedat Camp Lejeune to gain experience

upoa wtucb LO e v d u p c tbe i m p l d o n of a full-scale facility; ~~rbot~B.ee-peowotedyprdw~CMbecomportedpndbeneficirrllyfeused; Establish & d w J o p e procedures for meeting patbogea reduction requirements; chprscreriotico and dem>astrote suitable uses of the resulting c o m p o s ; t and FurtheF &tine solid w.de reduction capabilities and equipment requirements ofa full-scale solid waste compog! k i l i t y . This paper ,womarizes procedures used to successfullycoordinate and implementtheyear-longpilot project. It also preseats the results obtained through c o m p o s t i n g various ratios of permitted solid waste materials. Windrow mixes, formption techniques, huning regimes, and moisture additioo requirements are discussed. The d u tq umpookd mptetirrlr have beep subject to numerous laboratory analyses. Thecharacteristics of the canpmt rue discuosed in tbe p a p aa w d as product distribution details and d t s .

COORDINATION PROCESS

T b project was inithdby t& Base Envinxuneatal Manageaxat Depprtment,EnviraMlentol Compliance Division, Pdlutioa Prwdiua sectioo rod was conductedat the Bme sanitary lpodfill by the Facilities Department, Bme MPiaterrPlrce Diviioa, Reeds rod Grwnds Section. Technical catroctor support was provided by Pprsons Engineering Science. M d y meetings were held pmong project participants to ensure that the project stayed on track. Diocuofiolr bpi= i n c l u d e d planned windrow mixes, progressto dab, problems and observations,and finisbed m a e t d a p p l i d o a projects. Meeting participants routinely included State regulators, temperature takers, mess hall manager, horticulturist, equipmeat operators, project support contractor, and project k g e r . Time regular monthly meetings proved very valuable in providing an opportunity for input from various and buy-in, and kept open the lines of communication among the vuious BMC depummb. Moot Import.ntly, it helped pave the way from a pilot project to a full-scale pemaneatly &g solid waste compost facility. M d y meetings were also supplemented by daily commuaicatioo between the temperahue taker, project amager, and equipment operator supervisor. This helped to &lit& d rsinforce standad operating procedures, ensure that windrow turning or moisture addition was rccomplished (LO n eeded,and m a im id i the occurrence of windrow failure. Bpse persoaoel, promoted projed bmktorming, synergy,

PRE-COMPOSTING CONSIDERATIONS A primary coosideration before officially beginning the pilot compost project was to have appropriate windrow turning equipment on site. In the past, a front end loader had been used to turn yard waste windrows. That processwasextremelytime consuming, did not adequatelyinvertwindrows,andresulted in extensive

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incorporatioa of soil into windrows. Although the project p e r m i t was received in November 1994, the project was September 1995 when windrow turning equipment was available.

not officially initiated until

A secondpry project consideration was manpower limitations. The additional tasks associated with this project - food waste collection, paper collection, temperaturetaking, windrow turning, project monitoring, record keeping, and project management were all incorporatedinto work schedulesofexistingpersonnel.When considering permpneptly sustpining the level of effort necesspry to operate the pilotor expanding from the level of effort required to d u c t the pilot to a larger d e project, optimizing limited menpower resources was critical.

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WINDROW MATERIALS

An objective ofthe pilot project was to evaluate the composebility and compatibility of severalsolid waste stresms geoerpted at Camp Lejeune. The Stnteisnred permit allows the following materialsto be composted at the project site:

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Yard waste including grass clippings, twigs, leaves, and pine needles; Untreated wood waste including tree branches, large limbs, and stumps; Food waste from mess halls; *Cormgated cardbonrd, clean or soiled; Paper such aa undeliverable bulk mail from the Base Post Office; * H o n e mpoure from the Bsse stables; Water oofteaino lime sludge; Wpstew.ter treahmt plant sludge; and Wood ash from the biomass project.

sources.

Yard w as&,untreated wood waste, and paper provide primary windrow carbon Yard and paper wastes are deposited a d co-mingled in a designated area wherethey are stockpiled until anew windrow isformed. wben a oew w i d r o w is formed, yard and paper wastes are processed through the tub grinder. This eliminates large limbs that might jamb windrow turning equipment and helps to jump start the yard waste decomposition process. Through experimentation,use of a one-inchscreen on the tub grinder was determined to be most effective. Use of a tinex ecree~cauaed the bullring ageat to breakdown too m n resulting in too little pore space in the windrows. It waa Joo f d that yardwaste should be ground as close as possible to the timeof windrow formation. W k m ground yard wpptB wp8 otoclpiled, it began to decompose prior to being formed id0 windrows. This was especially detrimeotal during the d y molrths of the project wheowindrow nutrient soutces were minimal due to limitatioas 011 the amount of food waste that could be collected and colder ambient air temperatunxi. This was not the case with untreated wood waste which owld be ground or chipped into one-inch sized piecesahead of its scheduled use md stockpiled wrccessfully in a designated area at the project site.

Food waste, horse manure, d wastewater treatment plant sludge provide primary windrow nitrogen sources. Food waste is collected in water-tight containers individually serviced and transported to the project site, Monday through Friday. Food waste is added to a windrow on a daily basis during a two-week period after windrow base materials are laid down. Several food waste collection containers were already used at mess halls to collect k i t c h residuals for laadfilling; severalothers were purchased to increase the quantity of food waste that could be collected d diverted to the compost project. Pulpers to process kitchen residuals were already in place at Camp Lejeune mess halls and have proven to be valuable to help with the consistency of the food waste. The pulpers can be adjusted to reduce or increase the amountof free liquidin the food waste. As the project continues, it is believed that the w e of these pulpers can be refined to minimize the addition of water to windrows by increasing the liquid coateat of the food waste during dryer periods of the year and vice versa. However, the amount of liquid in the food waste will be limited by the collection process. Wastewater treatment plant sludge is added M (L nutried supplement only and is deposited when a new windrow is being formed. Soiled corrugated cardboard was also successfullycomposted in some windrows. The cardboard was contaminated with food residuals, vegetables oils, etc., and was separated at the Base materials recovery facility from material slated for recycling. Cardboard was delivered separately to the project site and was processed in the

tub grinder when a new windrow was being formed. It was mixed with yard waste at a ratio of approximatelythree parts yard waste to one part shredded cardboardand used in forming the initial windrow prior to adding food waste.

Horse manure was used successfully in several windrows but has proven to be difficult to collect. Unlike the othermaterialscomposted,horsemanurewas not previouslycollectedandlandfilled.Themanurewas stockpiled at the Base stables and picked up by gardeners for use on garden plots. Stockpiled manure was added to some windrows but did not enhance the process enough to warrant the additional labor collection cost. Water softening lime sludge was included in the pilot to determine if the resulting compost could be enhanced by its addition. This material presents a management problemto the Base as there is no established means of disposal or reuse currently other than the Base landfill. Each of the materials listed above was used during the first eight months of the pilot project with the exception of the water softening lime sludgeand wood ash. Water softening lime sludge is scheduledto be included in awindrow to be formed in July1996. Wood ash is anticipated to be available in August 1996 when an experimental biomass energy generating facility, under construction at Camp Lejeune by the U.S. Environmental Protection Agency, will be operational. During the first eight monthsof the project approximately 1071 tons of yard, wood and paper waste were usedin forming 15 windrows. The ratio of food waste to yard and wood waste increased considerably over the course of the project. In the first windrows, the ratio was a low as 1 part food waste to 10 parts yard and wood waste. In the more recently constructed windrows, the ratio has increased to 1 part food waste to 2 parts yard and wood yaste. A total of 230 tons of food waste, 7 tons of wastewater treatment plant sludge, and 29 tons of horse manure were composted. The pilot compost project has also been used to divert some special food wastes from the Base landfill. For example, several tons of pasta which could not be served due to expired shelf- life were added to a windrow composed of yard and food waste. The pasta presented a special handling problem because it was so dry. The pasta was soaked in water for several hours prior to being mixed into the windrow. Water also had to be added several times during the composting cycle.

WINDROW OPERATIONS Standard procedures for windrow formation were developedas the pilot project progressed. This section discusses procedures used in forming, monitoring, and turning the windrows. A spreadsheet data management system was develop to track daily procedures, windrow composition, and monitoring results for each windrow.

Windrow Formation Standard operating procedures during the project have been to form a new windrow approximately every two weeks. This schedule was developed primarily due to the limited amount of food waste able to be collected. Fifteen to 20 tons of food waste could be collected within a two-week period. A windrow of approximately60 feet long provided an adequate carbon to nitrogen ratio using the available food waste. Extending windrow formation time to greater than two weeks resulted in limited success reachingpathogen reduction temperaturesequal orgreater than 131 degrees F and maintaining that temperature for 15 days. The windrow often began to heat up during the time food waste was being added andthen cool off before the requisite 15 days after the last of the food waste was added. A 60 foot windrow could also be turned in a relatively short time period allowing adequate turning time for all active windrows given available manpower resources. The bulking agent of ground yard wastes, chipped wood wastes, and paper was formed into a windrow approximately 60 to 80 feet long, 12 feet wide, and six feet tall. The size was determined by the capabilities of the windrow turner and to minimize required windrow turning time. In windrows where sludge or horse manure was used, it was added during initial windrow formation with the bulking agent. After the bulkmg agent was formed into a windrow, food waste waS added during the next ten work days. Food waste was placed daily in a

trench on the top of the windrow and covered with b u h g agent. During the last five days of food waste addition, tbe windrow was turned after each food waste addition. Thrs provided good mixing of the ingredients before the stprt of tbe 15&y potbogen reduction cycle during which the windrow was maintained at or above 13 1 degrees F and turned at least five times.

Eoch active windrowwas d t o r e d daily for temperatures, odor, and moisture. Temperature monitoring wna performed using a four foot probe; odor and moisture monitoring were determined subjectively. Temperstures were recofded from four, evenly-spaced locations dong the windrow at depths of two and four feet into the The temperature rwdings from the two foot depth were used for monitoring achievement of bmperohres sufficient to destroy pathogens. Temperntures were not recorded on weekends. For purpores of achievingpdwgeo reduction, temperatures were considered to remain at the temperrrtures recorded on Friday as loog PO the kmpmtum recorded on Monday were dso above 131 degrees F. Temperature monitoring was continued after the 15&y pathogea reduction cycle was documented, though on a less frequent h i s . Compost was not distributeduntil the tempemure of the windrow stabilized at less t h 35 ~degrees F aboveambient tem~erotureowitbout turning to emwe that the material was sufficiently cured. If the temperature of.windrows coatinued to remain high, the windrow was turned.

windr~~.

Although temperature was the primpry indicator used to determine when windrows needed to be turned, windrow odor and moisture were also noted daily and considered for this purpose. This assessment was made at the sorqe time that temperahues were The following standardized terms were defined for assessing odor d moisture CaOdiriaaE of windrows:

recorded.

Moisture; W~-wwcrterrunsoutw~ahpodfulofmPterirrlissqueezed Moist handful of mpterirrl fonns a ball under moderate pressure and holds together for at least 15 d Dry not poaoibie to form a ball with mpterial thot holds together for at least 15 seconds Very Dry dust evideat when material handled

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If a windrow was described as smelling likea m m o & or rotten eggs, or was 'wet", it was turned that day. If a windrow was rated as dry, the windrow was sprayed with wateras soon as practical unless rain was forecasted for that day or the next day. Because the facility is uncovered, it is extremely susceptible to weather conditions which requires operotors to be extremely flexible. In addition, standard operating proceduresmust change with the seasons.

An oxygen meter was recentlypurchased to enhancewindrow monitoring effectiveness. Theoxygen quantification allows more accurate information on microbial activity. The meter serves as an aid in determining the need to turn the windrow by indicating the oxygen level present in the windrow.

A Scat windrow tumer model 482B pulled by a bulldozer was used to turn the windrows. In addition to initial turning of the windrows during the formation periodto mix and aerate the materials, windrows were turned periodically to increase oxygenandincorporatemoisture. The need forturningwasprimarilydetermined by pssessing thetemperaturereadings and moisture and odor ratings. When temperaturesstartedtodrop to

approximately 134 degrees F, the windrow was turned that day. Also, if temperatures escalated to 150 degrees F or higher, the windrow was turned that day. When the moisture rating was "wet", the windrow was turned that day, some times as many as four times in one day to provide adequate aeration. This proved to be particularly important in the colder months. After pathogen reduction temperatures were achieved for the required 15 days, turning was continued on a less frequent and urgent basis. Turning helped to ensure the compost was cured and to reduce the compost moisture level to that necessary to screen the material (dryer material screened more easily).

ANALYTICAL, MONITORING Prior to distributing compost from the pilot project, finished compost was sampled and subjectedto several laboratory analyses. Generally, windrows were sampled once every three months. A composite sample from each windrow was analyzed for: percent moisture, percent humic matter, nitrogen, phosphorus, potassium, soluble salts, pH,cadmium,copper,iron,lead,nickel,selenium, and zinc. Forwindrows towhichsludgewasadded,the composite sample was also analyzed for mercury and arsenic. The composite samples were collectedby hand auguring into each windrow at approximately four evenly spaced points. Thesample material was pulled fromapproximately two feet into thecomposting mass. The compost from all sample pointswas mixed in a stainless steel bowl. A sample box, supplied by the laboratory, was filled with approximately one cup of material from the bowl. These samples were analyzed by the State of North CarolinaDepartment of Agriculture Soil andAgriculturalWasteLaboratories.Theselaboratoriesoffervery reasonably priced services to the State agricultural community. For windrows to which sludge was added, the compositesampleswerealso analyzed for mercuryandarsenic. The Statelaboratories do notperform these analyses so a private laboratory in Jacksonville, North Carolina was used. In addition to the chemical parameters listed above, the composite sample foreach windrow completed within a quarter (three month period) were further composited into one sample which was analyzed for fecal coliforms. Analytical data for the windrows sampled to date is compiled in Table 1.

DATA MANAGEMENT A spreadsheet wasdeveloped using Lotus 1-2-3 software to organize the daily monitoring information from the windrows as well as the analytical results of quarterly sampling. The spreadsheet includes cells where the following information is entered: Date of windrow formation; Approximate tonnages and cubic yardages of materials in each windrow; Daily temperature, moisture, and odor ratings; Nutrient and metals concentrations; and Volume of material in windrow following compostingand curing. Usingtheentereddata, the spreadsheetcalculatesthepercentreduction of materialachievedthrough composting. Temperatures are also graphed to demonstrate achievement of sufficient temperatures for pathogen reduction.

DISTRIBUTION Prior to material screening, the compost was sufficiently cured (asdemonstrated by temperature that did not rise to more than 35 degrees F above ambient air temperatures without turning) and analytical results from sampling were received and reviewed. Screening was found to greatly increase the usefulness of the material by improving the texture and removing contaminants such as plastic and metal debris and large sticks. A three-sort screenerwas used producingoversizeddebris,medium sized compostmaterial,andfinelyscreenedcompost material.Afterthe cured material was screened, the medium and finely screened materials were distributed to selected locations where the material was used as topsoil amendment. 19

Base soils are primarily sandy loam with little topsoil. Limited topsoil resources are available throughout the Base raising the value of the fished compost to the rnaintennnce and &cement of Camp Lejeune's grounds. The finishaj compost semes M m important topsoil amendment d will provide a continual s o w of valuable topsoil amedmnt material. Compost was first applied as part of a coordinated effort to improve the grounds around barracks. Denuded were covered with approximately 8 to 10 truck loads of material which were used as a top dressing mixed with mil and tben seeded with grass during the second week of April. Within a few weeks the seed was

law

ptep6

germhated and provided approxixuately 90 percent coverage over the area. Future projects will include application to food plots when wildlife fodder is grown, the Base golf course, a newly constructed range, landing strips,tank fTpils,andBfo4iooprolre~.

Uee of the tinisbed compost m a t e d will be promoted though Camp Lejeune's self-help program which available to Marine and civilian units to pccomplish s d projects. This mechanism was succeoofullyuaed b rssbn the bamcka grounds during the pilot project. Given the limited budget and labor pool for g d mpintnnnncc, the self-help programwill be M important mechanism to utilize the m a t e d . Md~twmnlly,coatractors working aboard Base CJU be given occes6 to government furaished,mpterials, such as the finisbed c o m p o s ,tto u8e in contracted projects.

& e ad

LESSONS LEARNED By d u c t i n g this project, Camp Ljeune has gained the necessary experience to determine the extent to which long-term municipal d i d waste composting canbe feasibly d u c t e d aboard Base. Along the way, numeleswa~w e l e a r n e d that e n a b l e d the project to be successful. ~hese~essonsare s u m m ~ r i ~ ebelow: d

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success.

Firor and foremost, project buy-inis d o l to ehsure project This included support fnw all pertiso involved in or rssociatcd with the projectincluding mPnagement personnel,waste geperptora, C d e lco tro, d compoft equipmeat operrrton. All parties must listen to the requirements of others and be wilknp and ab& to rewin flexible and alter standard practices where

mxssary.

. . - Daily communicrrtion between all parties

helpsto ward off problemsearly and provide quicker aolutiaas to p d e m s when they wereencountered.Adequatecommunication wasaconstanteffort, especially as playen changed throughout the life of the project.

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w - Smaller is not necessarily better. Processing materials in tub a grinderwitha =rea smaller than oaeioch in sile produced a b u b g agent that was too fine to provide adequate windrow pore space. Am, with smaller ~ctee~p, wear increased on the grinding equipmentandprocessingtimeincreased. sooOer is not necessrrrily b&& t h la ~ter. Grindingyardwaste to be used forbulkingagent must be done immediately prior to wiodrow f d m . Grinding too far in advance and then stockpiling mptefiol can waste the errergy pwmted by its decompocitioa. Ooce g r d . tbe natural decomposition of tbe yard waste is ecceleratd. This initial beating is useful to 'jump start' the composting process, especially when minimal nitrogen sources are available, M was the case in the fall d winter months.

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Food Waste P ul~h Pulping food waste proved to be very advantageous because it produced a uniform m a t e d .The pulped food waste composted at a relatively even rate and minimized the presence of large pieces of food (fruit) in the f d product. In addition, pulped food waste tended to stay in place in windrows. Items such as whole fruit had a tendency to roll away from the windrow during turning.

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It is easier to establish standad operatingprocedureswith a limited,manageable number of sbort wmdrows. This minimi.rpd the M o u n t of m a e t d to be handled in a given amount of time and increased operation flexibility. In &tion, this approach resulted in less m a e td to rehandle if a particular windrow did not compost well.

ODeratinn ProceQureS

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Procedures will vary from season to season due to variab!e

temperatures and rainfall in eastern No& Carolina and the uncovered project site. B u h g agent variability also requires sepsoapl operation a d j u t a a t s . Increased quantities of gnus in spring and summer reduces the need for supplepseotd water; increased quantities of leaves in the fall and winter increases the need for supplemeatal water.

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S c d g is an a d d i t i o d step that isworth the time and equipmentinvestment. It serves to remove contaminants resulting in a more desirable horticultural material. The finished product is more uniform in size and is relatively Free of cootaminants such as plastic and metal debris and large wood pieces.

Water - Easy pcce88 b large quantities of water is essential. It was not uncommon to spray 1,OOO to 2,000 gallaaa of water on active windrows on a given day during some times of the year eve0 at this small pilot project site.

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- Turning is required frequeotlyduring

food waste additionand the active

composting

@ of patbogem reduction. W l m temperotureo were above 134 degrees F, frequeot turning (one or more times per day) did not a d v d y impact the decomposrtioo pmcess as long as windrows had adequate moisture. When

temperaturea were lower, 131 to 133 degrees F, turning some times resulted in temperptures dropping below 13 1 degrees F the next b y .

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Curiqg Finished compost should be kept in windrows rather than a large stockpile priorto scteeoing. M a t e d that was stockpiled was wetter than windrowed material and therefore more difficult for the s c h g equipment to process. Stockpiled material was windrowed and turned several times for several days to dry out the material prior to screening.

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Camp Lejeune compost tested high in soluble salts and thus is not suitable as a straight plan&ngmedium. For exaq.de, it should only be used as potting soil for plants when mixed with soil or peat moss at8 d o of r~ I d l:l.

CONCLUSIONS Thc experieoce gained through this pilot project provides important insights for other installations or local governments seeking to achieve similar solid waste reduction goals or compost program objectives. Department of Defense loftnllotioashave a unique opportunity in the communities and states in which they are l o c a t e d : they can take the lead in implementing innovative solid waste management and reduction programs such as this and demoastrate their commitmeat b environmeatnl quality and resource conservation. Such a proactive approach to this issue reflects positively oo the Department of Defense and on the high quality of p e r s o d leadership at each installation.

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