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With more than 250 million tiresdiscarded annually (approximately onetire per person), and that number show-ing no signs of declining, the scrap-tiremarket continues to search for newuses for old tires. One growing marketfor recycled tires is the onsite waste-water treatment industry, which usesthem for aggregate in soil absorptionsystems. Just one manufacturer in Geor-gia, for instance, processes more than10 million tires per year, and approxi-mately two-thirds of these chips areused as onsite system aggregate.

Using tire chips as aggregate forconventional septic systems has beenapproved by a number of states, in-cluding South Carolina, New Mexico,Iowa, Virginia, and Arkansas. “I thinkothers should give this a look,” saidCarl Graves, environmental health spe-cialist, Arkansas Department ofHealth, Little Rock, Arkansas. “It reallysurprises me the number of wastetires you can use in a standard absorp-tion system. An average system withfive, 60-foot lines, for example, would

Waste Tire MarketsMarkets exist for more than 75 per-

cent of the nation’s waste tires, accord-ing to South Carolina’s 2001 WasteTire Management Report. Some ofthese markets include tire-derived fuel,playground cover, running surfaces, soilamendments, flooring and matting,roofing shingles, road-fill applications,and rubber-modified asphalt.

Tire Chip Performance ResearchResearch has proven tire chips are a

viable alternative to gravel. (See “Analy-sis of Tire Chips as a Substitute forStone Aggregate in Nitrification Trench-es of Onsite Septic Systems: Status andNotes on the Comparative Macrobiolo-gy of Tire Chip Versus Stone AggregateTrenches,” in this issue of Small FlowsQuarterly, page 18.)

Systems that fail using tire chips asaggregate would be treated the sameas systems that fail using gravel as ag-gregate. “I sincerely doubt it would bea fire threat to leave tire chips in thedrainfield of a failed system as long as

use approximately 1,400 to 1,500used tires. As an environmentalist, Ithink using that many tires for just onesystem is a good deal.”

Scrap Tire LawsHistorically, waste tires took up

space in landfills or became breedinggrounds for mosquitoes and rodentswhen stockpiled or illegally dumped.This changed in 1985 when Minnesotaenacted the first state law for managingscrap tires. Since 1985, all but twostates, Alaska and Delaware, have en-acted a similar state law. The threeareas that states have generally focusedon are program management for scraptires, creation of market developmentprograms, and stockpile abatement.According to the Rubber Manufactur-ers Association, 38 states ban wholetires from landfills, 35 states allowshredded tires to be placed in landfills,11 states ban all scrap tires from land-fills, 17 states allow processed tires tobe placed into monofills, and 8 stateshave no landfill restrictions.

NSFC STAFF WRITER

Caigan M. McKenzie

A Growing Trend as Aggregate in Soil Absorption Systems

the shreds do not exceed 10 feet deep.Typically, tire chips in a drain mediumare no more than 3 feet deep, andthat’s just not enough to build up a criti-cal mass of heat to cause a fire,” saidMichael Blumenthal, senior technical di-rector, Rubber Manufacturers Associa-tion, Washington, D.C.

Cost ConsiderationsSources indicate that aggregate

costs can be reduced by 10 to 90 per-cent when tire shreds are used inplace of gravel. Savings depend upona number of variables, including howplentiful gravel is, distributor’s sellingprice, and freight costs (both distanceand weight; a cubic yard of gravelweighs about 2,800 pounds, as com-pared with a cubic yard of tire chips,which weighs only 800 pounds).

“We use a ton of gravel for everyseven feet of trench. A ton of tirechips goes 21 feet,” said Bob Ar-doyno, tire chip distributor and septicsystem installer in Waycross, Georgia.“In a job that is 3 lines, 70 feet long,I’d use one truck load of tire chips. If Iused gravel, I’d need two truckloads.It costs me more travel time, morefuel costs, more wear and tear on mytruck (a job requiring 75 tons of gravelcan be done with 25 tons of tirechips), and more money for aggre-gate,” said Ardoyno. “My profits dou-bled when I made the switch.”

Increased profit is one reason Ar-doyno expanded his system installa-tion business to include distributingtire chips. “One of my customersspent $150,000 for gravel, money fora driver to haul it 125 miles, and pur-chased a big truck to carry the load.After I explained how he could reducecosts while increasing profit by usingtire chips, he sold the truck, droppedthe driver, and increased his profit bymore than $75,000 doing the sameamount of work he had done the pre-vious year. But even stories such as hisdon’t impress some people. Some ofour ‘mom and pop’ corporations havebeen burned trying new things in thepast, so they like sticking to the oldway,” Ardoyno said.

Tire chips increase the drainfieldstorage capacity by 30 percent be-cause the void space between tirechips (62 percent) is greater than thevoid space for gravel (44 percent).Drainfield size is unaffected.

End-User Rebate ProgramsSome states have end-user rebate

programs, including processors inLouisiana and Oklahoma, and end-usersin Utah, Virginia, Colorado, Iowa, andNebraska. Virginia’s end-user rebateprogram began in 1997, and, accordingto Allan Lassiter, manager of Virginia’swaste tire management program for theDepartment of Environmental Quality,Richmond, Virginia, they have no plansto stop it.

“The way the program works in Vir-ginia is that the end user is reimbursedup to $22.50 a ton for tires originatingfrom a tire retailer and $100 a ton fortires recovered from a certified stockpilein the state,” Lassiter said. “We track itthrough a certificate that the retailer is-sues to the hauler at the time the wastetires are picked up. The certificate hasfour duplicate pages. The top sheet hasa signature line for the tire retailer, tirehauler, tire collector, and tire processor.As the certificate moves from retailer toprocessor, each signs the top sheet andretains a duplicate copy of the certificate.

“After the certificate has all the nec-essary signatures, the installer submitsthe form to the Department of Environ-mental Quality and is reimbursed forthe cash value of the certificate. Some-times, installers share the money withthe processors and the homeowners.

“We even pay installers from otherstates, as long as they use Virginia tires.North Carolina, for instance, processesa substantial number of our tires,” Las-siter said, “and if an installer from anoth-er state buys our tires from them, we’llcut a check for them, too.”

Iowa Experiments with TireChips in Sand Filters andConstructed Wetlands

Brent Parker, senior environmentalengineer, Department of Natural Re-sources, with the state of Iowa, award-ed money from his waste managementaccount to Appanoose, Davis, Lucas,and Monroe (ADLM) Counties so thatthey could put in some experimentalsystems using tire chips as aggregate.“ADLM has soil with a high clay content(Armstrong, Shelby, Garra, and Edina),so instead of soil absorption trenches,they use sand filters. Tire chips replacedrock in the distribution and collectionareas. They also used tire chips in con-structed wetlands,” Parker said.

Bill Milani, a sanitarian in ADLM,used tire chips in 24 systems, a combi-nation of sand filters and constructedwetlands. “We started using tire chipsin 1999, but we’ve only completedone year of our two-year continuouswater sampling tests because of con-struction delays. In another year, we’llhave conclusive results about the sys-tems’ performance. So far, tire chipsare working well in the subsurfacesand filters,” Milani said.

“Because of freight costs, it wasn’tas cost-effective as we had hoped. Riverrock in this part of Iowa is inexpensiveand plentiful ($9 a ton, washed). Onthe other hand, because tire chips areso light, you get a lot more for your dol-lar than you do with river rock.

“As construction grows and riverrock supplies decrease, it might makesense to use tire chips more frequent-ly. There are some changes I’d make,

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A subsurface-flow constructed wetland cell in Iowa uses tire chips as aggregate. Photo by Bill Milani.

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though. I’d want debeaded tire chips(wires completely removed). Althoughmore costly, it would eliminate theaesthetic problem iron deposits createat the end of the cells—red water. Itwould also eliminate the safety prob-lem (slicing the handler) wires cause.Another change I’d make is to screenthe pipes to prevent chips (1.5 to 2inches) from floating into them, clog-ging the pipes,” Milani said.

Milani filled the 18-inch-deep con-structed wetlands with 12 inches oftire chips and 6 inches of gravel. Lay-ering the tire chips with gravel servedtwo purposes: it ensured the tire chipswouldn’t be moved about by thewind, and it helped plants root better.

While Milani said tire chips wereeasy to rake, he pointed out theywere bouncy, making it difficult towalk on them. He also noticed somesettling after a year.

South Carolina First State to UseTire Chips as Aggregate

Tire chips are frequently used insouthern states because soil is sandy,and rock quarries are nonexistent. Theidea for using tire chips in South Car-olina originated from a conversationbetween Clifton Roberts, public healthofficial, Horton County, South Caroli-na, and a manufacturer in the north-ern part of the county. This manufac-turer used the sidewalls of truck tiresto produce pivot wheels for rotarymowing machines called bushhogs. (Arotary mower is an instrument used tochop down bushes and undergrowth.)He took the remaining pieces of side-wall and stacked them together withlong, threaded rods, making them intodrain tile. He chipped the rest of therubber for aggregate in drainage ditch-es and French drains. Wondering if itwould work for soil absorption sys-tems, he asked Roberts to test it.

Armed with a five-gallon bucket oftire chips, Roberts and Steve Baxley,county supervisor, Conway, SouthCarolina, tested its storage capacityand found it had more void spacethan rock. Roberts took the idea tothe health department in Columbia,and they agreed to use tire chips asaggregate in soil absorption systemson an experimental basis. After moni-toring the systems and seeing noproblems with surfacing or malfunc-tioning, South Carolina approvedusing tire chips as aggregate.

We have had a number of installersquit using tire chips, though, becausethey found them difficult to spreadwhen they put them in the trench andtried to level them,” said Graves.

Ardoyno cautions against dismiss-ing tire chips as an alternative tooquickly. “The chips do have spring tothem, but once you get used to them,you should find them easier to workwith and faster to use than gravel be-cause they weigh two-thirds less. Theyare also much easier on your equip-ment,” said Ardoyno. Both Graves andArdoyno warn that wire rods protrud-ing from tire chips could cause a flattire on a backhoe if you don’t fill yourtires with sealant that immediatelyseals tire punctures.

New MexicoTwo years ago, Steve Walker, pro-

gram manager in the New Mexico En-vironment Department, agreed to per-mit five systems using tire chips on anexperimental basis after he was ap-proached by a newly-formed tire pro-cessing company. After observing thefirst system, which was installed at thetire-processing site, Walker noted sev-eral problems. First, wire protrudedfrom some of the chips in such excessthat they resembled spider webs, liter-ally slicing those who handled thechips. Second, the processed tirechunks were small and flat. “They re-sembled a stack of Pringles™. Therewas very little space between them,”said Walker. “The processor operatedon a tight budget, and I don’t think hisshredder functioned properly. Someof the tires were cut, and some wereripped apart, and the chips the shred-der produced from car tires were toosmall for aggregate. Tires from largeearthmovers produced nice sizedchunks, but they were rare to find be-cause the tires can be retreaded.”

Before Walker could documentthe system and monitor its perform-ance, the tire processing plant burneddown and was never reestablished,leaving the remaining four permittedsystems undone. “If using tire chipsas aggregate was proposed to meagain, I would try it, but I would bemore discerning about the shape andsize of the chip and the amount ofwire left in,” said Walker. “Having theright shredder is critical. Right now,the tire chip business in our area isdead for lack of a manufacturer.”

South Carolina has used tire chipsas aggregate in septic drainfields since1993, and contractors and health offi-cials are satisfied with the results.“Over the last 5 years, we have in-stalled approximately 5,048 septic sys-tems, 98 percent of which have tirechips for aggregate,” said Baxley.Horry County alone uses more thanone million tires per year as aggregatefor drainfields.

The demand for tire chips hasgrown quicker than the number ofprocessors, making tire chips a scarcecommodity in South Carolina. “Mostof the chippers we use are in NorthCarolina, and since North Carolina justapproved the use of tire chips thisyear, their tire chip market has explod-ed,” Baxley said.

ArkansasFour years ago, the Arkansas De-

partment of Environment Quality urgedthe Department of Health to considerapproving scrap tire chips for use as ag-gregate in soil absorption systems. “Wehad lots of questions about how wellthey would perform and if they wouldcause a public health problem,” Gravessaid. “After considerable research, wefelt it was worth trying. We modeledour guidelines after Virginia’s and SouthCarolina’s.”

Arkansas has not experienced anyproblems with properly installed sys-tems using tire chips as aggregate, butthey have experienced some problemswith operators and installers. For ex-ample, laborers for one operatorweren’t careful using the backhoe andscooped up too much dirt with thechips. This dirt ended up in the ab-sorption field, clogging it. A local envi-ronmental specialist worked with theoperator to correct the problem. An-other problem Arkansas experiencedwas holes in backhoe tires from thetwo-inch metal rods that came fromchipped truck tires. They’ve eliminatedthat problem by switching to chippedcar tires that don’t have the metalrods. Sometimes too much metal wasattached to the chips because proces-sors didn’t keep the teeth on theirshredders sharpened.

“Some installers have commentedthat they feel more confident on steepsites with a backhoe bucket of tirechips than they do with a bucket ofgravel, because tire chips are so muchlighter. They also see much more ag-gregate for their dollar with tire chips.

Top: Bottom layer of trench with 6 inchesof chips and 4-inch pipe. Middle: Pipe cov-ered with 2 inches of chips Bottom: Tirechips covered with geotextile material.Job ready for inspection by health depart-ment. Photos courtesy of Bob’s Septic TankCompany, Waycross, Georgia.

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Quality Control“When I first started distributing

tire chips, I told the processor ourbusiness relationship wasn’t going towork without strict quality control,”Ardoyno said. “I can’t ship junk topeople. It would never pass thehealth department’s inspection. Iturned down five loads recentlywhen the processor brought in anew manager. It took a lot of work toget it right, but now the quality isgood,” Ardoyno said.

When Ardoyno sells tire chips toinstallers for the first time, he prefersto go on a job with them and showthem the best way to work withthem. “In small rural towns, yourname can become pretty mucked upif you don’t do things right,” Ardoynosaid. “For example, you might havesome people down at the local cof-fee shop talking about their installa-tion, saying tire chips were left allover their property. Now what’s aproperty owner going to do with ahalf ton of tire chips. The wires fromthe chips could slice their foot openif they aren’t wearing heavy shoes.

“I can’t have that happen. If in-stallers don’t want to do it right, Iwon’t sell to them.”

Ardoyno points out that tire chipsneed to be covered with a geotextilematerial rather than the treated paperused to cover gravel because thewire would rip the paper, allowingdirt to get into the trenches.

Everyone WinsUsing tire chips as aggregate for

drainfields is a great way to recycletires. It saves the homeowner moneyand increases the installer’s profit.

Because rock quarries are com-monplace in Alabama, the cost differ-ence between tire chips and gravel isnegligible. In a recent presentation topublic officials and wastewater pro-fessionals in Alabama, Ardoyno ex-plained that using tire chips as aggre-gate would completely eradicate Al-abama’s waste tire problem. “Thenumber of onsite septic systems in-stalled in 1998 in Alabama was26,500 with an average drainfield lin-ear footage of 275, or 825 square

feet. The average number of rubber tiresused in an average drainfield was 1,100.This means that one ton of rubber tirechips will provide 10 inches of aggre-gate for a drainfield that is approximate-ly 26 linear feet long and 36 incheswide. Based on the average drainfieldsize, 4,600 septic tanks would totallyeliminate the 5,048,600 tires discardedin Alabama in 1999,” said Ardoyno.

Future of Tire Chips as Aggregate Most installers that have used tire

chips say they wouldn’t go back to tradi-tional materials. There are a number ofreasons why tire shreds are becomingwidely accepted by the septic systemconstruction industry.

Tire chips contain 62 percent voidspace, as compared to 44 percent withstone. This allows tire chips to holdmore water than stone. Tire chips arelighter than stone, making it easier towork with the tire chips, cutting installa-tion time in half and enabling installersto put in twice as many units a day.Freight costs are drastically reduced be-cause of the variance in weight betweentire chips and gravel. Tire chips are lessexpensive than stone, sometimes evenhundreds of dollars less, and in somestates, installers are awarded with a re-bate for using tire chips. Tire chips donot significantly compact, therefore 12inches of tire chips is equivalent to 12inches of washed gravel. Stories aboutcompaction are few and involve sandysoil. Using tire chips helps the environ-ment by eliminating the need to exca-vate natural rock and provides an alter-native to tire disposal.

Using tire chips as aggregate in on-site systems has gained favor in manyparts of the country. While tire chipshave been proven to be a viable alterna-tive to gravel, expanding their usethroughout the country will be basedon approval from appropriate stateagencies and economics. In areas of thecountry where tire chips are less expen-sive than stone and where state regula-tions do not restrict this application, it isexpected that this market will expand.

For more information contactGraves, Arkansas DOH, (501) 661-2584; Blumenthal, Rubber Manufactur-ers Association, (202) 682-4800; Ar-doyno, Bob’s Septic Tank Company,(912) 283-6727; Lassiter, Virginia’s DEQ,(804) 698-4215; Parker, Iowa’s Dept. ofNatural Resources, (515) 725-0337; Mi-lani, Iowa (641) 437-1909; and Baxley,South Carolina DOH and EnvironmentalControl (843) 248-1506.

monolandfills) (10). Because of thehigh volume of waste tires, problemsassociated with their disposal, aesthet-ic problems, and the expansion and in-novation of reuse of used tire productsis being addressed aggressively.Chipped or shredded tires are beingused for a wide variety of products, in-cluding playground covers, doormats,roadbed, fill, shoes, and aggregate sub-stitute in septic system drainfields. This

Analysis of Tire Chips as a Substitute for Stone Aggregate in Nitrification Trenches of Onsite Septic Systems:

Note: This white paper has been reviewed by North Carolina’s OnSite Wastewater Section—Department of Environmental Health (DEH-OSWS) and approved for publication. Approval does notsignify that the contents necessarily reflect the views and policies of DEH-OSWS. The mention of tradenames or commercial products does not constitute an endorsement or recommendation for use.

paper will describe and analyze the cur-rent available information on the use oftire chips as a substitute for stone ag-gregate in septic system drainfields.

In more than 17 states, tirechips/shreds are currently permitted foruse or are under experimental evalua-tion as an aggregate substitute for stoneaggregate in septic system drainfields.Some of the scrap tires in North Carolinaare being chipped and exported to

By Barbara Hartley Grimes, Ph.D., Steve Steinbeck, P.G., and Aziz Amoozegar, Ph.D.

It is estimated that at least 250 mil-lion tires (about one tire per person)are discarded annually in the UnitedStates (21). This high number of usedtires presents a significant problem fordisposal and has led to intense re-search and development for reusingand recycling tires. In a two-year peri-od (1999 and 2000), counties inNorth Carolina reported receiving 9.5million tires (136,536 tons in

Status and Notes on the Comparative Macrobiologyof Tire Chip Versus Stone Aggregate Trenches

A tire chip processor in action inCameron, North Carolina. Photo courtesy of Tim Warren.

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South Carolina for use in septic systems.Tire chips have recently been approvedas an aggregate for septic systems inNorth Carolina. (See Approval: www.deh.enr.state.nc.us/oww).

The number of discarded tires usedin onsite systems can be significant. Forexample, approximately 2.3 million pas-senger tire equivalents in Georgia, 300tons of tire chips in Iowa, 100 milliontires in Florida, and about 30 percent ofused tires in Oklahoma are being usedin septic systems.

Specifications and Definitions:General Description of Tire Chips

Tires can be cut into small piecescalled tire chips or tire shreds by vari-ous techniques. The New York StateRoundtable defines chips as “A classi-fied scrap tire . . . which is generallytwo inches (50.8mm) or smaller andhas most of the wire removed …” andshreds as “Pieces of scrap tires that . . .are generally between 50mm (1.97”)and 305 mm (12.02”) in size”(11). Thephysical characteristics of the tirechips, such as size, wire protrusion,and fines are controllable factors inthe processing of tire chips. Based onthis, the term tire “chips” is more suit-able as a substitute for stone aggre-gate than the term tire “shreds.”

According to the Texas NaturalResource Council Commission(TNRCC), while passenger tires mayvary in size and shape, they have simi-lar general physical and chemical char-acteristics and are composed approxi-mately of 85 percent carbon, 10 to 15percent ferric material, and 0.9 to 1.25percent sulfur (20). (More specific infor-mation on rubber, metals, and othercompounds in tires can be found inAppendix I.) For example, studies haveshown that new versus used tire chipshave similar performance when used asaggregate in septic systems (18).

The relatively stable structure oftire chips makes them a suitable sub-stitute for stone aggregate in the sep-tic system. In addition, tire chips arethree times lighter than stone aggre-gate (e.g., a cubic yard of stone aggre-gate is 2,800 pounds and a cubic yardof tire shreds is 800 pounds). Also, inmany cases, tire chips have shown tobe one-third the cost of stone aggre-gate for use in septic systems (18).

Regulations in states where tirechips are approved as a substitute forstone aggregate in onsite systems re-quire them to be of similar size as

stone aggregate (approx 2 inches),with wire protrusion of 0.5 inches orless. These regulations also require a“no fines limit” and geotextile fabricto cover the tire chips before groundcovering. This is a general overview,and examples of specific regulationsin some southeastern states can befound in Appendix II.

The major differences in state reg-ulations are in the percent of tirechips meeting specification required(80 percent, 90 percent, etc.) and theoversight, inspection and /or certifica-tion of the tire chip specifications(Appendix II). Few states address thebead wires, cleanup, and any limits ondepth to groundwater, other thanstandard installation requirements.

Main Issues in Tire Chip Substi-tution (Demonstration/Experi-mental Projects)

Concerns for tire chip use includestorage, handling of chips with protrud-ing wires, post-installation cleanup ofstray tire chips, potential for compres-sion or compaction, and durability ofthe chips. In storage, the accumulationof dirt and stray materials needs to beprevented. Persons handling the chipsshould use care, wear thick gloves andappropriate clothing (including thick-soled shoes), and have current tetanusprotection. Cleanup must be addressedin the post-installation inspection.

Research has shown that com-paction is not a significant problem, andour inspection of tire chips in the trench-es of a number of 8-year-old drainfieldsin South Carolina revealed that the tirechips were not degraded or damagedby wear. These demonstrate the durabili-ty of tire chips in septic system drain-fields. Recommendations have beenmade from several research/demonstra-tions projects that tire chips should befirmly compacted prior to covering withgeotextile fabric.

One field survey conducted in SouthCarolina did not show a significant num-ber of failures in tire chip systems thatwere greater than 10 years old or evi-dence of settling problems over thedrainfields. Porosity was found to behigher with tire chips than stone (60 per-cent for tire chips; 40 percent for stone)(13, 16–18).

Sewage Distribution, Performance,and Biomat Formation

Performance studies comparingstone aggregate drainlines and tirechip aggregate drainlines in variouscombinations of alternating drainfieldsand alternating drainlines show in allcases equivalent or similar wastewaterdispersal to the soils within the trenchesfilled with stone aggregate and tire chipsdrainfields (2,13,16–18). Permeability oftire chips was found to be equal tothat of stone aggregate. In some cases,less ponding was recorded in the tirechip systems than systems that wereconstructed using stone aggregate(13,16–18).

Waste treatment efficiency in allstudies using tire chips was equivalentto that achieved in stone aggregatedrainfields. Wastewater treatment test-ing in more than one project examinedBOD5, COD, TSS, ammonia-nitrogen,nitrate, fecal coliforms, and pH, andshowed equivalent treatment, except

Top: Tire chips before installation. Bottom:Tire chips excavated from system eight yearslater shows growth of biofilm and lack oftire chip decomposition. Photos courtesy ofBarbara Grimes.

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that the wastewater treatment efficien-cy in tire chip trenches sometimestook several months to reach the samerates. Conductivity profiles demon-strated little precipitation in either typeof aggregate (13,16–18).

Biomat formation and macrobiolo-gy of tire chips in comparison to stoneaggregate systems examined in NorthCarolina and South Carolina (AppendixIII) demonstrated a thicker biomat anda surprising level of supported inverte-brates in the tire chip trenches. Onlynematodes were found in a two-year-old system in North Carolina. demon-strating an aerated system that allowsthem to provide an additional treat-ment of waste constituents.

In the South Carolina systems (olderthan 8 years), we found more trophiclevels (feeding types) of micro- andmacro-organisms, which indicated a sta-ble ecological wastewater treatmentcommunity (1, 5, 14, 15, 22). The or-ganisms included grazers, saprophyticfeeders, and filter feeders. This complex-ity and diversity of organisms demon-strates the potential for additional levelsof wastewater treatment in tire chip ag-gregate, keeps the biomat pores open,promotes healthy biomat regrowth bygrazing, and indicates a healthy and di-verse ecosystem in the tire chip trench-es (1, 5, 14, 15, 22).

In comparison, only a few proto-zoa were found in a stone aggregatesystem in South Carolina. Evaluation ofboth stone aggregate and tire chip sys-

tems that were overloaded (i.e. highlevel of ponding) showed that thehealthy ecosystem was not present intire chip trenches when overloaded.

A Question of LeachatesMajor in-depth studies of leachate

from tire chip versus stone aggregatedrainfields, include: Amoozegar andRobarg, 1999 (2) in North Carolina;Burnell and Omber, 1997 (3);Envirologic, 1990 (6); Liu. Mead, andStacer, 1998 (8); Robinson, 2000 (13);Sengupta and Miller, 1999 and 2000(16, 17); and Spagnoli, Weber, andZicari, 2001 (18).

One of the major questions raisedin using tire chips as a substitution forstone aggregate is the potential leach-ing of various constituents from thetire chips. Bench studies and field test-ing have examined tire chip leachateunder normal and “worst case sce-nario” conditions (2, 3, 6, 8, 13, 16,17, 18). The pollutants of interest inthese studies indicate that volatile andsemi-volatile compounds do not enterthe leachate. Other studies havedemonstrated that ground rubber andtire chips actually remove some of theorganic compounds from fluids perco-lating through them (7, 18).

Studies under typical septic sys-tem conditions have shown that tirechip leachate and stone aggregateleachate contain high concentrationsof iron (16, 17). The levels of iron,which is a secondary drinking water

contaminant (aesthet-ic), however, does notseem to pose a healthproblem. The studiesat the Chelsea Centershowed that tire chipswere actually a sink foriron when comparedto the influent concen-tration (16, 17).

In some studies,manganese (secondarydrinking water stan-dards) was higher inthe tire chip leachatethan in the aggregateleachate (18). In theChelsea Center studies,on the other hand,manganese concentra-tion was mostly con-stant in the effluent inthe D-box, but was ofequivalent concentra-tions in stone aggre-gate and tire chips in

the trenches although fluctuating inboth—being sometimes higher in theaggregate and sometimes higher in thetire chips (16, 17).

In the Chelsea studies, zincleachate was lower than secondarydrinking water standards; in bothtrench types, zinc concentrations werelower than in the distribution box whileparalleling D-box fluctuations (17).

As for the effluent macrobiologyin the trenches, it appears that the ironin the presence of some unknown fac-tor(s) in tire chips enhances macrobio-logical growth. Accumulation of harm-ful trace metals does not appear tooccur as evident by the biologicalgrowth in the South Carolina systems.

Overall, it appears that tire chipsubstitution for stone aggregate is anexcellent alternative for onsite systemsin regard to wastewater treatment,durability, and economics. Using tirechip aggregate in septic systems alsoprovides a viable solution to recyclingused tire waste. As a result of the data,a 1:1 substitution was recommendedand approved for use in NorthCarolina. Because of the biologicalstudies (and other researchers’ recom-mendation (18) and, we do not recom-mend tire chips be used for areas withseasonal high water tables, using lessthan one foot separation for Group 1(sand, loamy sand) (1.5 feet in sandysoils), or conditions (e.g., undersizing)that result in overloading the drain-fields. Additionally, physical hazards,worker safety, and compliance with thespecifications must be addressed.

Barbara Hartley Grimes, Ph.D., isthe NonPoint Source PollutionProgram coordinator and SteveSteinbeck, P.G., NonPoint SourcePollution Program team leader withthe Onsite Wastewater Section of theDivision of Environmental Health,North Carolina Department ofEnvironment and Natural Resources.Aziz Amoozegar, Ph.D., is a professorin the Department of Soil Science atNorth Carolina State University.

References1. Ali, Arshad, Moh Leng Kok-Yokomi, and J.

Bruce Alexander. 1991. Vertical Distribu-tion of Psychoda alternata (Diptera: Psy-chodidae) in Soil Receiving WastewaterUtilized for Turf Cultivation. J. of MosquitoControl Association: Volume 12, Number2:287 –289.

2. Amoozegar, Aziz and Wayne P. Robarge.1999. Evaluation of Tire Chips as a Substi-tute for Gravel in the Trenches of SepticSystems. Final Report for the Division ofPollution Prevention and Environmental

This demonstration installation of tire chips in a septic systemin North Carolina featured the use of a steel brace for support-ing the distribution pipe while the chips were loaded into thetrench. Photo courtesy of Tim Warren.

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21

General Tire Composition(Modified 1999 TNRCC Fact Sheet):Weight: Passenger Tire 18.7–20.0 pounds

Truck tire about 100 poundsVolume:

Number of Tires Needed for One cubic yard: Car Tires 10Truck Tires 3Shredded car tires (1 pass) 33Shredded truck tires (1 pass) 7Shredded car tires (2 inch chips) 47

Basic Ingredients:Fabric: Steel, nylon, aramid fiber, rayon, fiberglass, or polyester

(usually a combination)Rubber: Natural and synthetic (hundreds of polymer types)Reinforcing chemicals: Carbon black, silica, resinsAnti-degradants: Antioxidants/ozonants, paraffin waxesAdhesion Promoters: Cobalt salts, brass on wire, resins on fabricsCuratives: Cure accelerators, activators, sulfurProcessing aids: Oils, tackifiers, peptizers, softeners

Composition of One Popular All-Season Passenger Tire:Weight : 21 poundsComposition: 30 different synthetic rubbers 5 lbs

8 types of natural rubber 4 lbs8 types of carbon black 5 lbssteel cord for belts 1 lbpolyester and nylon 1 lbsteel bead wire < 1 lb40 chemicals, waxes, oils, etc 3 lbs

Approximate composition Percentages:85% carbon10-15% ferric material0.9-1.25% sulfur

Typical Percentages of Rubber Mix in Some Types of Tires:Synthetic Rubber Natural Rubber

Passenger tire 55% 45%Light Truck Tire 50% 50%

TRNCC Information :Using Tire Shreds in Onsite Sewage Facilities (Septic Systems)Shreds are three times lighter than stone aggregate:

Cubic yard of stone aggregate: 2,800 poundsCubic yard of tire shreds: 800 pounds

APPENDIX I

Assistance; Department of Environmentand Natural Resources and ChathamCounty Board of Commissioners. 133 pp.http://www.p2pays.org/ref/03/02627.pdf

3. Burnell, B.N. and McOmber, G. 1997.Used Tires as a Substitute for DrainfieldAggregate: Site Characterization and De-sign of On-site Septic Systems. ASTM STP1324: MS Bedinger, JS Fleming, & AI John-son, Eds. Am. Society for Testing Materials.

4. Daniels, Joe and Bruce Bird , 1993 . A Re-port on the Use of Scrap Tire Shreds asSoil Absorption Media. Prepared for theKansas Department of Health an Environ-ment Local Protection Plan Grant. 8 pp.

5. Feuchen, McGarry, and Marc eds. In“Water Wastes and Health in Hot Cli-mates”. Flies causing Nuisance and Allergy1977 John Wiley, New York p. 291-298.

6. Envirologic, Inc. (1990), “A Report on theUse of Shredded Scrap Tires in On-SiteSewage Disposal Systems,” by Envirologic,Inc., Brattleboro, Vermont, for Departmentof Environmental Conservation, State ofVermont, 9 p.

7. Gunasekara, A. S., J. A. Donovan, and B.Xing. 2000. Ground discarded tires removenaphthalene, toluene, and mercury fromwater. Chemosphere 2000 Oct.41(8):1155-60.

8. Liu, H.S., Mead, J.L., and Stacer, R.G.(1998).Environmental Impacts of RecycledRubber in Light Fill Applications: Summaryand Evaluation of Existing Literature. Tech-nical Report #2. Plastics Conversion Pro-ject. Chelsea Center for Recycling and Eco-nomic Development, University of Massa-chusetts, Lowell. 18 p.

9. North Carolina Solid Waste ManagementAnnual Report (1996- June, 1997) March1998. Published by: Division of WasteManagement; Division of Pollution Preven-tion and Environmental Assistance, andDepartment of Environment and NaturalResources 25 pp.

10.North Carolina Solid Waste ManagementAnnual Report (1999- June, 2000) March2001. Published by: Division of WasteManagement; Division of Pollution Preven-tion and Environmental Assistance, andDepartment of Environment and NaturalResources 25 pp. http://wastenot.enr.state.nc.us/swhome/annrep.htm

11.NYS Roundtable Consensus on Tire Man-agement Parameters for Legislative Devel-opment: March, 2000. http://www.rma.org/scrap_tires/state_issues/index.cfm

12.Onsite Wastewater Section—Division of En-vironmental Health—NC Department of En-vironment and Natural Resources WebPage: Rules, Information, Programs, Innov-ative and Experimental Approvals/ Applica-tions, etc. http://www.deh.enr.state.nc.us/oww/

13. Robinson, Sharon J. (Feb.) 2000. The Useof Chipped Tires as Alternate Aggregate inSeptic System Leach Fields, MS thesis inCivil Engineering. State University if NY.Syracuse.234pp

14. Scott, Harold George. 1961. Filter FlyControl at Sewage Plants. The Sanitarian:Vol. 24(1): 14-17.

15. Steinhaus, E. H. and F. J. Brinley, 1957.Some relationships between bacteria andcertain sewage-inhabiting insects. MosquitoNews 17:299-302.

16. Sengupta, S and H. Miller, 1999. Prelimi-nary Investigation of Tire Shred for Use in

Residential Subsurface Leaching Field Sys-tems: A Field Scale Study. Technical Re-port #12. Chelsea Center for Recyclingand Economic Development, Universityof Massachusetts, Lowell. 12 p.

17. Sengupta, S and H. Miller, 2000. Investi-gation of Tire Shred for Use in ResidentialSubsurface Leaching Field Systems: AField Scale Study. Technical Report #32.Chelsea Center for Recycling and Eco-nomic Development, University of Massa-chusetts, Lowell. 33 p.

18. Spagnoli, J, AS Weber, and LP Zicari, Sep-tember 2001. The Use of Tire Chips inSeptic System Leachfields. Center for Inte-grated Waste Management, University atBuffalo, Buffalo, New York. 92pp.

19. TNRCC Information: The Composition ofa Tire: Waste Tire Recycling Program Of-fice of Permitting, Texas Natural ResourceConservation Commission , P.O Box13087. Austin, Texas 78711-3087.Septem-ber 1999

20. TNRCC Information: Using Tire Shreds inOn-Site Sewage Facilities (Septic Systems)11-3087. September 1999.

21. USEPA, August, 1999. A Quick ReferenceGuide. 1999 Update. EPA-530-B-99-002.

22. Usinger, R. L. and W. R. Kellen, 1955. TheRole of Insects in Sewage Disposal Beds.Hilgardia. J. of Agricultural Science (Cali-fornia Agricultural Experiment Station).Vol. 23(10): 263-321.

Sm

all F

low

s Q

ua

rte

rly,

Fal

l 200

3, V

olum

e 4,

Num

ber

4

22

APPE

NDIX

II

TIRE

CHI

P AG

GREG

ATE

SUBS

TITU

TION

FO

R GR

AVEL

IN O

NSIT

E SY

STEM

S:Ex

ampl

es o

f Sou

thea

ster

n St

ate

Rule

s

GEO

RG

IA

F-

19:

Tire

chi

pap

prov

alw

hen

inst

alle

d on

conv

entio

nal

sept

ic ta

nksy

stem

crite

ria a

ndab

sorp

tion

field

met

hods

SOU

THCA

RO

LIN

AR

evis

ed,

1995

VIR

GIN

IAR

evis

ed19

97

NO

RTH

CAR

OLI

NA

NEW

LYAP

PRO

VED

OCT

. 200

2

The

abso

rptio

n lin

e w

ithtir

e ch

ip a

ggre

gate

mus

tbe

cov

ered

with

an

appr

oved

geo

text

ilefa

bric

or

silk

scr

een

prio

rto

bac

k fil

ling

Abso

rptio

n tr

ench

esm

ust b

e co

vere

d w

ithge

otex

tile

(syn

thet

ic)

fabr

ic p

rior

to b

ackf

illin

g

Dep

artm

ent o

f Hea

lthR

egul

atio

n Ap

plic

atio

nU

ntre

ated

bui

ldin

g pa

per

or g

eote

xtile

(sy

nthe

tic)

fabr

ic c

over

sha

ll be

used

to c

over

the

tire

chip

s be

fore

bac

kfill

ing

The

tire

chip

agg

rega

tesh

all b

e co

vere

d w

ith a

sing

le a

nd c

ontin

uous

laye

r of

non

-wov

en fi

lter

fabr

ic e

xten

ding

acr

oss

the

top

of th

e tir

e ch

ipag

greg

ate

befo

reba

ckfil

ling.

The

fabr

icsh

all h

ave

a un

it w

eigh

tof

at l

east

3.0

oz.

/yd2

(per

AST

M D

-526

1), a

perm

ittiv

ity o

f at l

east

1.0

sec-

1 (p

er A

STM

D-

4491

), a

trap

ezoi

d te

arst

reng

th o

f at l

east

35

lbs.

(pe

r AS

TM D

-453

3),

and

have

a m

esh

size

equa

l to

U.S

. Sie

ve N

o.70

(A.

O.S

.)(AS

TM D

-47

51).

"1. A

ll tir

e ch

ips

not u

sed

in th

eni

trifi

catio

ntr

ench

sha

ll be

rem

oved

from

the

site

by

the

inst

alle

r or

cont

ract

or fo

rth

e on

site

was

tew

ater

syst

em.

2. N

o so

il sh

all

cont

amin

ate

the

tire

chip

sdu

ring

inst

alla

tion.

1. F

or L

PP s

yste

ms,

the

orifi

ces

shal

l be

prot

ecte

d fr

om a

g-gr

egat

e sh

adow

ing

by s

leev

ing

the

dis-

char

ge p

ipe

late

rals

with

in th

e pe

rfor

ated

pipe

[w

hich

mee

tsR

ule

.195

5(e)

] ty

pi-

cally

use

d fo

r co

n-ve

ntio

nal n

itrifi

catio

nlin

es.

2. T

he m

inim

um v

er-

tical

sep

arat

ion

re-

quire

d by

Rul

e 15

AN

CAC

18A

.195

5(m

)sh

all n

ot b

e re

duce

d,no

twith

stan

ding

the

use

of a

ny a

dvan

ced

was

tew

ater

trea

t-m

ent s

yste

m.

1. A

ny ti

re p

roce

ssor

wis

hing

to p

rovi

de ti

re c

hip

aggr

egat

efo

r us

e in

ons

ite s

ewag

etr

eatm

ent a

nd d

ispo

sal s

ys-

tem

dra

infie

lds

in th

e st

ate

ofN

orth

Car

olin

a sh

all r

ecei

vew

ritte

n ap

prov

al fr

om D

ENR

-D

EH-O

SWS.

Tire

Pro

cess

ors

mus

t pro

vide

pro

of th

at th

eyca

n co

ntin

uous

ly p

rodu

ce a

tire

chip

coa

rse

aggr

egat

e in

conf

orm

ance

with

the

spec

i-fic

atio

ns in

II o

f thi

s ap

prov

al;

Tire

pro

cess

ors

shal

l sub

-m

it a

repr

esen

tativ

e sa

mpl

eof

tire

chi

ps to

DEH

OSW

S ;

The

proc

esso

r sh

all h

ave

sam

ples

ana

lyze

d b

y a

third

part

y la

bora

tory

qua

lifie

d to

cond

uct p

artic

le s

ize

anal

ysis

for

com

plia

nce

with

the

abov

e sp

ecifi

catio

ns ;

Doc

umen

tatio

nof

tire

proc

esso

rs’

prod

uct

mee

ting

the

abov

esp

ecifi

catio

ns,

shal

l be

subm

itted

as

requ

este

d, a

tle

ast y

early

, to

OSW

S ;

Nonc

ompl

ianc

ew

ith th

isap

prov

al m

aysu

bjec

t a ti

repr

oces

sor

tosu

spen

sion

or

revo

catio

n of

thei

r ap

prov

al

Tire

Ch

ips

Tire

Ch

ips

Tire

Ch

ips

Tire

Ch

ips

X X X X

The

aggr

egat

em

ust b

e fr

ee o

fba

lls o

f wire

and

fine

rubb

erpa

rtic

les.

The

chip

s m

ust

be c

lean

and

free

of a

ny s

oil

part

icle

s ei

ther

adhe

ring

to th

ech

ips

or fl

oat-

ing

loos

e w

ithin

the

chip

s.

Fine

s ar

epr

ohib

ited

DEQ

< 2

mm

are

proh

ibite

d

Shal

l be

clea

nan

d fr

ee (

98%

or b

ette

r by

wei

ght)

of a

nyso

il pa

rtic

les

(fin

es)

eith

erad

herin

g to

the

chip

s or

float

ing

loos

ew

ithin

the

chip

s;

The

size

of t

he ti

rech

ip a

ggre

gate

shal

l be

one-

half

totw

o in

ches

indi

amet

er

Chip

s m

ay n

ot b

esm

alle

r th

an o

ne-

half

inch

or

larg

erth

an fo

ur in

ches

insi

ze

DEQ

Nom

inal

two

(2)

inch

es in

siz

e m

ayra

nge

from

1/2

inch

to a

max

imum

of f

our

(4)

inch

es in

any

one

dire

ctio

n

1. S

hall

beno

min

ally

two

(2)

inch

es in

siz

e an

dm

ay r

ange

from

_in

ch to

am

axim

um o

f fou

r(4

) in

ches

in a

nyon

e di

rect

ion

(95%

or

bette

r by

wei

ght)

;

2. S

hall

be g

rade

dor

siz

ed in

acco

rdan

ce w

ithsi

ze n

umbe

rs 2

, 3,

and

24 o

f AST

MD

-448

(st

anda

rdsi

zes

of c

oars

eag

greg

ate)

The

perc

enta

geof

tire

chi

pag

greg

ate

with

grea

ter

than

one-

half

inch

expo

sed

wire

shal

l not

exc

eed

ten

perc

ent

Wire

str

ands

may

not

prot

rude

mor

eth

an o

ne-h

alf

inch

from

the

side

s of

the

chip

s

DEQ

Expo

sed

wire

may

pro

trud

eno

mor

e th

anon

e-ha

lf in

chfr

om th

e ch

ip

Shal

l not

cont

ain

wire

prot

rudi

ngm

ore

than

one

-ha

lf in

ch fr

omth

e si

des

of th

ech

ips

(95%

or

bette

r by

wei

ght)

; and

The

perc

enta

ge o

ftir

e ch

ipag

greg

ate

with

grea

ter

than

one

-ha

lf in

ch e

xpos

edw

ire s

hall

not

exce

ed te

npe

rcen

t

At le

ast 9

0% o

fth

e ch

ips

mus

tm

eet t

he te

chni

cal

spec

ifica

tions

DEQ

At l

east

95%

of th

e ag

greg

ate

by w

eigh

t sha

llco

mpl

y w

ithsp

ecifi

catio

nsro

utin

ely,

Proc

esso

rsin

spec

ted

regu

larly

. Sem

ian

nual

cont

ract

ors

OSW

S At

leas

t95

% o

f the

aggr

egat

e by

wei

ght s

hall

com

ply

with

the

sizi

ngst

anda

rds;

Tire

proc

esso

rs m

ust

be a

ppro

ved

byO

SWS

year

ly

STAT

E

TERM USE

D:

Chips o

r Shre

ds Bead W

ire Fines

Dimen

sions

Wire Prot

rusion

s

Percen

t Com

plian

ce

Geotex

tile

Fabri

c

Meetin

g

Spec

ifica

tions

Other Req

uirem

ents

Other Res

tricti

ons

Proces

sors

Approv

al

Approv

al

Contin

ued

The

min

imum

dep

th o

fag

greg

ate

shal

l be

twel

vein

ches

with

six

inch

es b

elow

Tire

rec

ycle

rs m

ay, a

t the

irop

tion,

sub

mit

chip

sam

ples

toth

e D

ivis

ion

for

eval

uatio

n. T

here

sults

will

not

con

stitu

te a

gene

ral o

r bl

anke

t app

rova

l for

any

prod

ucer

. The

act

ual,

final

appr

oval

of t

ire c

hips

occ

ur a

tea

ch s

eptic

sys

tem

job

site

Each

inst

alla

tion

mus

t hav

e a

valid

VD

H p

erm

it ; m

ust b

eau

thor

ized

by

the

prop

erty

owne

r an

d ce

rtifi

ed b

y VD

Han

d th

e in

stal

latio

n co

ntra

ctor

usin

g th

e 4

part

VD

H-D

EQCe

rtifi

catio

n of

Use

of T

ireCh

ips

in a

Res

-iden

tial S

eptic

Dra

infie

ld

Tire

chi

p ag

greg

ate

for

subs

ur-

face

sew

age

efflu

ent a

bsor

p-tio

n sy

stem

s sh

ippe

d fr

om a

p-pr

oved

tire

pro

cess

ors

shal

l be

acco

mpa

nied

by

a fr

eigh

t bill

of la

ding

labe

led

as d

rain

field

aggr

egat

e . T

he b

ill-o

f-la

ding

shal

l ce

rtify

that

the

mat

eria

lm

eets

the

spec

ifica

tions

for

drai

nfie

ld u

se. C

ontr

acto

rs p

ur-

chas

ing

tire

chip

coa

rse

aggr

e-ga

te s

hall

reta

in a

cop

y of

the

frei

ght b

ill-o

f-la

ding

as

docu

-m

enta

tion

of th

e tir

e ch

ip a

g-gr

egat

e si

ze a

nd q

ualit

y. A

copy

of t

he b

ill o

f lad

ing

shal

lbe

pro

vide

d to

the

loca

l hea

lthde

part

men

t prio

r to

issu

ance

of th

e op

erat

ion

perm

it, a

ndsh

all b

e re

tain

ed w

ith th

e op

er-

atio

n pe

rmit

filed

with

the

loca

lhe

alth

dep

artm

ent.

APPENDIX III

Sm

all F

low

s Qu

arte

rly, F

all 2003, Volum

e 4, Num

ber 4

23

NC Experimental wastewater system (1): NC rules of conventional installa-tion. (Approval online OSWS) Dr. Aziz Amoozegar Soil Science NCSU Sys-tem with alternating stone aggregate trenches and tire chip trenches. Re-sults of sampling the biomat for protozoa and metazoa (higher forms)

Excavation

Tire chips: well-structured “honeycomb” does not collapse on excavationStone aggregate: no structure; collapses on excavation

Appearance of AggregateTire chips: intact, good separations, covered in a “fuzzy beige biofilm,” wires oxidized and mostly gone. Stone aggregate: fairly clean—no attached biofilm

Biomat Underneath The Aggregate

Tire chip trenches: well-formed biomat trench bottom—blackStone aggregate trenches: well-formed biomat—dark

Macrobiology

Tire chip trenches: No protozoa; nematodes in abundanceStone aggregate trenches: No protozoa or nematodes

South Carolina Septic Systems (6) —installed SC rules: Drain line directlyon soil, then aggregate, covered geotextile fabric. Tire chip systems arewidely used in Horry County, S.C. Sampled near Conway, S.C.—MobileHome Park with both types of systems and soils—at least 8 years old. Re-sults of sampling the biomats for protozoa and metazoa (higher forms)(asalways, other factors involved—heavy rains days before our trip)

Excavation

Tire chips: well-structured “honeycomb” does not collapse on excava-tion. After 8 years drainfield was not collapsed—well structured

Stone aggregate: no structure ; collapses on excavation

Appearance of AggregateTire chips: intact, not pitted, covered in a “fuzzy beige biofilm,” wires oxidized, almost gone.

Stone aggregate: fairly clean—no attached biofilm

Biomat Underneath The AggregateTire chip trenches: well-formed biomat trench bottom—thick (several mm) black sheet of biofilm; somewhat intact

Stone aggregate trenches: well-formed biomat—very thin (mm) dark beige/black

Macrobiology

Tire chip systems sampledI. Systems with effluent in trenches—no protozoa or metazoaII. Normal System—abundant forms

a. Protozoa—3 types of ciliatesb. Metazoa—oligochaetes (aquatic /segmented worms)

(3 types at least – maybe some parts…)c. Metazoa—nematoda (roundworms) somewhat abundantd. Metazoa—insect larva (psychodidae—filter fly/ drain fly)

Stone aggregate systemsI. Normal trenches—no protozoa or metazoa or

small protozoa later in culturesII. System with effluent in trenches—no protozoa or metazoa

Macrobiology Methodology: 2–8 years post-installation: hand digging in trenches;Evian water to wash out organisms from biomat. Dissecting microscope used toexamine the biomat and tire chips. Identification to taxonomic class.

Macrobiology

FLO

RID

A(t

ire c

hip

only

)

FLO

RID

A(t

ire c

hip

and

min

eral

aggr

egat

em

ix)

Rul

es:

Tire

chi

pco

arse

aggr

eg.

(Or

tire

aggr

eg.)

Use

of

mix

edtir

e an

dm

iner

alag

greg

ate

is appr

oved

*Sie

veSi

ze

Perc

ent

pass

ing

No

spec

s fo

r ge

otex

tile

fabr

ic

— 3/8

in

0-30

dom

estic

stre

ngth

was

teon

ly; t

ire c

hip

aggr

egat

esy

stem

s sh

all b

elim

ited

to n

ew o

rre

paire

d do

mes

ticon

site

sys

tem

s,an

d th

ose

inw

hich

the

botto

msu

rfac

e of

the

drai

nfie

ld is

at

leas

t 12

inch

esab

ove

the

wat

erta

ble

at th

ew

ette

st s

easo

n of

the

year

Man

ufac

ture

r App

rova

l&

Lab

elin

g (A

)An

y m

anuf

actu

rer

wis

hing

to p

ro-

vide

tire

chi

ps fo

r us

e in

ons

itese

wag

e tr

eatm

ent a

nd d

ispo

sal

syst

em d

rain

field

s in

the

stat

e of

Flor

ida

mus

t firs

t rec

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searchers and the general public, planners, man-agers, state officials, public health officials, and fi-nance officers.

The cost of this book is $19.50. Request item#FMBKGN210.

Everything You Always Wanted To KnowAbout Septic Systems…But Didn’t KnowWho To Ask! Homeowner Version 1.0Environmental Health, Volusia County Health Depart-ment

This interactive CD ROM educates homeownersabout conventional onsite systems. The CD is divid-ed into six main sections, including

• the history of the modern septic system,

• public health issues,

• effluent characteristics,

• failures and repairs,

• frequently asked questions, and

• Web sites for additional information. The septic tank and

drainfield are further de-tailed through an ex-tensive video/slideshow that coverssuch topics asseptic tank re-quirements,use of dos-ing tanks,types oftanks to use,aerobic treat-ment units,drainfield loca-tion, what aggre-

38

Small Community Wastewater Solutions:A Guide to Making Treatment, Man-agement, and Financing Decisions

Ken Olsen, Bridget Chard, DougMalchow, and Don Hickman

This publication aims to helpproperty owners become criti-cal thinkers with respect to theinformation, concerns, andrecommendations that willsurface as they begin theprocess of solving their

wastewater problems.It also provides thetools small communi-ties need to accessthis data and to makeindependent, in-formed judgmentsand choices. The firstchapter offers a quickgrounding in waste-water problems; fol-lowed by a chapter-

by-chapter roadmap to small communitywastewater treatment solutions. It explains what thepeople in a community will need to do, includingwhat they need to know before making any deci-sions, sewage treatment system options, wastewatermanagement options, community organizationalstructure options, financing wastewater systems,working with professionals, and finally, implementa-tion of the plan. There is a glossary and several ap-pendices that include sample surveys, a summary oftreatment options, scientific abbreviations andmeasurements, and a guide to common acronyms.The book is a comprehensive guide to making com-munity wastewater treatment decisions. Local offi-cials and other community leaders will find it partic-ularly useful, and it is a good resource for re-

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39

gate and lateral pipe to use, and alternative soil ab-sorption systems. Although some sections arebased upon Florida regulations, this CD can be edit-ed to reflect regulations and requirements specificto any state or local jurisdiction. This CD ROM mayinterest those who work with or are in contact withhomeowners, such as public health officials, regula-tors, contractors, and developers, as well as the gen-eral public.

The cost of this CD is $6.50. Request item#WWCDPE76.

A Status of Tools and Support for Community Decentralized WastewaterSolutions National Decentralized Water Resources CapacityDevelopment Project

This report is the result of two 2002 workshops(organized by the Green Mountain Institute for En-vironmental Democracy and supported by the Na-tional Decentralized Water Resources Capacity De-velopment Project). The purpose of the workshops

was to better understand the services and toolsavailable to communities and how these tools andservices can be improved. Experts in the applica-tion of decentralized solutions met with representa-tives of community projects that had already decid-ed or were in the process of deciding on waste-water solutions. This report tries to identify situa-tions where additional effort can strengthen theparticipation of communities in making wastewaterdecisions that apply managed decentralized solu-tions, when appropriate.

The two workshops focused on distinct aspectsof decentralized wastewater system development.The first workshop emphasized the issue of interac-tions between community representatives and tech-nical experts, such as wastewater engineers. Thesecond workshop covered the relationship betweena community and state agencies that are requiredto regulate wastewater and often provide assistance.Both workshops were designed to recognize the

role of service providers in assisting communities.

The first part of this report is structured to runthrough each of the steps in the community processthat leads to the choice and implementation ofwastewater solutions. These steps constitute a “com-munity process.” From the observations noted, theremainder of the report identifies key findings thatprovide the basis for the last section of conclusions.This information will be useful to local officials, thegeneral public, planners, managers, state officials,state regulatory agencies, and engineers.

The CD is free. Request item #WWBKMG21.

Septic Systems for Wastewater DisposalAmerican Ground Water Trust

One-third of all American homes use onsitewastewater treatment systems;however, since septic systemsare out of sight, many home-owners rarely think aboutthem. When properly de-signed, installed, and main-tained, septic tanks and simi-lar onsite disposal systemsare effective from an engi-neering perspec-tive, eco-nomic forthe home-owners, andfriendly tothe environ-ment. Allstates haveseptic sys-tem regula-tions that areintended toprotectgroundwater.Most onsitewastewatersystems areused for homes that also have their drinking watersupplied by a well. In some rural and suburbanareas, sewer lines have to stretch great distances toconnect homes with a centralized treatment plant,making the connection to such systems impractical.Fortunately, in many rural areas, natural soils cantreat wastewater as thoroughly and safely (using anonsite disposal system) as municipal sewage treat-ment systems. This booklet provides basic septic sys-tem information for homeowners. It discusses severaltopics, including the purpose of wastewater disposalsystems; how septic tanks and aeration systems workand when to use them; the purpose of a soil absorp-tion system, how it works, and siting requirements;

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how to prevent system failure; and where to go foradditional information. This booklet will be useful topublic health officials, contractors/developers, andthe general public.

The cost of this booklet is 65 cents. Requestitem #WWBLPE75.

State Onsite Wastewater Regulatorsand Captains of Industry Conferences:Interactive CD ROM

National Small Flows Clearinghouse

This interactive CD-ROM documents the pro-ceedings of the 2002 State Onsite Wastewater Reg-ulators and Captains of Industry Conferences heldin Newport, RI, in March 2002. From each of theconference agendas, several full-text papers and/orpresentations as well as opening remarks can beviewed on screen or downloaded and printed. Top-ics include the status of onsite systems, pathogenand nutrient treatment and transport in soils, anoverview of Capacity Development work, clustersystems, onsite wastewater planning and zoning, amodel onsite system ordinance project, and U.S.EPA onsite wastewater initiatives. The CD also in-cludes a photo gallery, lists of attendees and pre-senters with their contact information, and addition-al resources, along with a follow-up article from theSmall Flows Quarterly. The CD-ROM will be of par-ticular interest to those wastewater professionals in-volved with onsite wastewater regulations, includinggovernment officials with regulatory oversight, localofficials, public health officials, engineers, manufac-turers, and consultants. To access the files on thisCD, you will need the following software: MicrosoftWindows (the CD is not Mac compatible), a Webbrowser (Microsoft Internet Explorer, Netscape Nav-igator, etc.), a media player, Adobe Acrobat Reader,Microsoft Word, Microsoft PowerPoint, MicrosoftExcel, and Corel WordPerfect. For some links, suchas QuickTime 6, you will also need a live Internetconnection.

The cost of this CD is $10.00. Request item#WWCDRG68.

Low-Pressure PipeSewage SystemInstallation andDesignTheo B. Terry

Design and installa-tion methods are crucialfor obtaining proper low-pressure pipe (LPP) sys-tem performance. TheLincoln Trial DistrictHealth Department (Ken-tucky) prepared this man-ual, which is intended to

be used as a voluntary reference for installers, in-spectors, and users of LPP sewage disposal systems.The table, charts, figures, and instructions in thismanual give detailed step-by-step procedures to usewhen designing LPP systems. A video titled Low-pressure Pipe Sewage Disposal System, Design andInstallation, also a National Small Flows Clearing-house product (#WWVTDM100) can be used inconjunction with the manual as a tool to train in-spectors and certified installers. This manual will behelpful to engineers, planners, managers, publichealth officials, operators, and contractors/develop-ers.

The cost of this booklet is $4.00. Request item#WWBLDM101.

Pumping Your Septic TankTeri King and Jodie Holdcroft

Septic maintenancecan extend the life ofyour septic sys-tem, protectwater quality,and also helpprotect publichealth. Thisbrochure explainswhy it is necessary toregularly pump your sep-tic tank. It lists the infor-mation that the pumpershould include on a receipt,such as tank size, construction,and number of compartments;effluent levels, tank condition, andscum and sludge levels; baffle con-dition; outlet baffle effluent filter;pump chamber and pump; drainfieldcondition; sewage disposal location; andany abnormal findings. The brochure includes abrief description about watertight septic tanks.Homeowners, public health officials, and local offi-cials will find this information useful.

The cost of this brochure is 40 cents. Request item#WWBRPE71.

Landscaping Your Septic Tanks Teri King and Jodie HoldcroftIn developing a site, it is important for homeownersto prepare a comprehensive plan for the property.This brochure describes different ways to plan alandscape design for optimum septic tank opera-tion. Information is provided about such topics asknowing your septic components for easy access,choosing the right plants, and a plant list. Thisbrochure will be useful for homeowners as theylandscape the area around their septic system.The cost of this brochure is 40 cents. Request item#WWBRPE72.S

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