Hazardous waste controlAre we creating problems for future generations?
Every year approximately one tonof hazardous waste is added to theenvironment for each person in theU.S. Although there is some disagreement and uncertainty about theexact amount of hazardous wasteproduced annually, there is a generalconsensus that the quantity subject tofederal regulation is in the range of 30to 60 million tons. Hazardous wasteexempted from federal regulation butcovered by state regulations adds another 230-260 million tons, makingthe total number of tons comparable tothe population of this country (seeTable 1).
Recently both the Office of Technology Assessment (OTA) and theNational Academy of Sciences (NAS)published reports on the managementof hazardous wastes. Although thesereports do not have the same focus,there is a striking similarity in theopinions and ideas contained in them.(The NAS report is oriented towardthe required control technologies,whereas the OTA report focusessomewhat more on changes in regulations that might improve hazardouswaste control.)
According to these reports, as muchas 80% of the 260-320 million tons ofhazardous waste produced annually isdisposed of in or on the land. Many ofthe hazardous materials placed inlandfills are highly toxic and remainhazardous for hundreds of years. Thecommittee that prepared the NASreport decided that "at least 500 yearsis realistic as a period of concern forhazardous wastes in landfills...."Regulations under the ResourceConservation and Recovery Act(RCRA), however, require monitoringfor only 30 years after a landfill isclosed. Therefore, it could begin to leaktoxic substances during the centuriesfollowing its shutdown, and the leakwould not be detected by legally required monitoring.
Also, there is a scientific consensusthat no matter how well a landfill isdesigned, no matter what the liner andcap are made of, the landfill eventuallywill leak. As the OTA report states,"even with new stricter RCRA regulations in place, eventual releases ofhazardous constituents from landdisposal facilities are highly probable."The NAS publication also concludesthat with time, the surface cover overa landfill can be penetrated and mobileconstituents can leak to groundwater.Thus, both studies conclude thatlandfills appear to be an inexpensivemethod of waste disposal, but becausethey require monitoring and maintenance for hundreds of years, theytransfer part of the cost of waste disposal to future generations. Eventually, 30 or 100 or 200 years laterwhenever the landfill begins toleak-more money will be spent tocontrol hazardous releases and contain
the wastes. These costs will be borne bygovernment or by society in generalinstead of by the generator. The 30year postclosure monitoring requirement hides the true cost of long-termcare.
Besides the too-short postclosuremonitoring requirement, the OTA andNAS reports say that existing regulations for landfills contain other deficiencies. Stringent monitoring is notrequired even while the landfill is inoperation. The regulations requiremerely that four ambient groundwatersamples be taken fOUf times a year. Noair monitoring is required to determineif emissions of volatile organic compounds pose a health hazard. Retrofitting to meet new standards, such asthe installation of a liner, is not required at existing active landfills, noris it required for those portions of existing landfills that do not yet containwaste. No geological strategies for
Recycled waste C Unknown Improper application of various materials EPA
a Wastes may be delisted on the basis of a petition that concerns only the constituents that have determined the original listing; however, other hazardousconstituents may be present that have previously been unrecognized administratively.b Wastes not identified as toxic by the EPA extraction procedure test and not otherwise listed by EPAC Legitimate recycling is exempt from RCRA regulations except for storage. However, there have been numerous incidents, such as the dioxin casein Missouri, involving recycled materials that are still hazardous.Source: Adapted from "Technologies and Management Strategies for Hazardous Waste Control"; U.S. Congress, Office of Technology Assessment,Washington, D.C. 20510
protecting drinking water supplies aremandated in regulations for siting newlandfills.
Hidden costsBoth NAS and OTA conclude that
lax policies regarding landfills makethem more economical than other alternatives and encourage industry touse them for nearly all its wastes. Ifindustry had to pay the true cost oflandfill disposal-the cost of containing the wastes over hundreds ofyears-it would be far more inclinedto use other methods. Alternatives toland disposal could cost 50-100% moretoday than current disposal costs. Butcleaning up newly created sites yearsfrom now might cost 10-100 times thisadditional outlay.
NAS and OTA advocate minimaluse of landfills and changes in regulations that will encourage the use ofother methods of disposal. Currentregulations, they say, provide disincentives for other disposal methods.Neither report states, however, thatlandfills can be eliminated entirely asa method of hazardous waste disposal.Both conclude that even with ideal
282A Environ. Sci. Technol., Vol. 17, No.7, 1983
waste disposal treatment methods,some wastes would have to be disposedof on land. But they agree that theamount of waste placed in landfills canbe reduced drastically.
Hierarchy of optionsRather than relying almost exclu
sivelyon land disposal, OTA and NASpropose that a hierarchy of options beused. "There are basically three general options," N AS writes, "Elimination [or reduction] or reuse of thehazardous waste, conversion of thehazardous waste into nonhazardous orless hazardous material, and perpetualstorage." These options and generalmethods for achieving them are diagramed in Figure 1.
Neither OTA nor NAS believesthat there is a panacea for all hazardous wastes. But NAS considers thefirst general set of options, which itcalls in-plant options, "probably themost economical and effective meansof managing hazardous wastes." Included in this category are processmodifications, such as altering thechemistry or certain other aspects ofengineering operations, and recycling
and reuse of the hazardous by-products. For certain wastes, processmodifications do not eliminate thewastes entirely but reduce their volumeor degree of hazard. For example,modifications to the mercury electrolysis cell have resulted in reductionsin the major types of waste producedby the chloralkali industry.
For the wastes that are not eliminated by in-plant options, NAS advocatesthatth~secondsetofoptionsbe
used-conversion of the hazardouswaste into nonhazardous or less hazardous material. The NAS committeemembers evaluated the state of development of the different methods in thiscategory and pointed out researchneeds in each area. Although chemicaland physical techniques could be used,in principle, to dispose of any hazardous waste, these methods would be tooexpensive for some wastes. The committee recommends that much additional research be performed in thisarea, such as:
• continued experimental determination of various hazardous wastespecies and mixtures;
• further development of processes
to remove metals from industrial wastestreams;
• further development of separationprocesses based on supercritical fluids,liquid membranes, and foam fractionation; and
• development of a low-cost processto remove water from slimes andsludges.
A large number of biological treatment processes exist that use indigenous or adapted microbes to remove ordetoxify wastes. NAS recommendsthat genetic engineering might beconsidered as a method to develop newspecies for this purpose.
At present, incineration provides themost complete means of disposing ofmany organic materials. NAS pointsout, however, that incineration hascertain drawbacks. For example, itoften requires emission controls andsampling and analysis of incinerationproducts. If inorganic materials arepresent in the waste, slag and ash areproduced as end products and must bedisposed of.
Unlike incineration, which requiresan open flame, thermal methods useheat to treat hazardous waste. NASmentions a number of techniques forthis purpose: catalytic and reactivefluidized bed systems, molten salt reactors, plasma arcs and torches, microwave systems, and pyrolytic processes.-The only thermal method thathas been used widely in industry is thepyrolytic process.
Land treatment (which is distinctfrom landfilling) is another methodthat has broad potential, according to
NAS. In land treatment, the top layerof soil, approximately 1 ft, is mixedwith the waste. Then, theoretically,chemical and biological reactions decompose part of the waste, part of it isadsorbed, and part of it, consisting ofcertain anionic inorganic fractions,migrates without causing violations ofdrinking water standards. For manywastes, pretreatment is ~ecessary before land treatment, to reduce theamount of land required and to reducethe amount of inorganic material inthe waste.
At present, ocean dumping of hazardous wastes violates some international accords. N AS and OTA notethat the scientific community does notagree about the effects of oceandumping and recommend that muchmore research be undertaken in thisarea. Except for studies of very specificmaterials in very specific areas, littleis known about the effects of hazardous wastes on the ocean environment.Both NAS and OTA suggest, however,that ocean dumping be reconsideredfor certain wastes. They believe thatthe ocean has the capacity to assimilate some kinds of hazardous materialswithout harm to human health orocean life.
As wastes are treated by one ormore options in the hierarchy mentioned previously, their volume andtoxicity are reduced. NAS and OTAagree that perpetual storage, the thirdstep in the hierarchy, should be usedfor as few materials as possible. Theyrecommend that after wastes, havepassed through the first two steps in
the hierarchy, those nonreducible toxicwastes that remain should be buried,for the most part, in the deep subsurface, thereby isolating them from thebiosphere. NAS notes that in the past,some wastes have been placed inabandoned salt mines and subsurfacecavities. It reports that not enoughresearch has been done to evaluate thesafety of such disposal, but recommends that with adequate research,this method can probably be used.NAS especially recommends investigating the possibility of using the thickunsaturated zones underlying parts ofthe arid western U.S. These zones arefree of water and could provide a largearea for waste disposal. "The utility ofthese zones may be pivotal in providinga reasonable solution to the wholeproblem of disposal of hazardouswaste," NAS reports. The committeealso suggests that an inventory ofpossible permanent disposal sites bemade.
Risk assessmentNo method of waste disposal is en
tirely risk free. To determine the safesttreatment for each type of waste, bothN AS and OTA recommend the use ofrisk assessment. OTA cautions, however, that it should be considered ananalytical tool for scientific input butnot a means of providing a final regulatory decision. It also cautions thatcomparisons used in risk assessmentmust include the nature and impact ofpotential releases and not merely whatpercent of the hazardous material isremoved or detoxified by the waste
FIGURE 1
The National Academy of Sciences recommends that wastes be'treated by one or more of three general methodscomprising the treatment hierarchy
In-plant options
Process Recycle andmanipulation reuse
I-Conversion of hazardous to less hazardous or nonhazardous
Land Thermal Chemical, Ocean andtreatment Incineration treatment physical and atmospheric
Source: "Management of Hazardous Industrial Wastes: Research and Development Neec!s"; National Materials Advisory Board, Commission on Engineering andTechnical Systems, National Research Council; National Academy Press: Washington, D.C., 1983
Environ. Sci. Technol., Vol. 17, No.7, 1983 283A
TABLE 2
An example of a hierarchical fee system for hazardouswastes based on the amount generated and the disposalmethod
Creation of new sites
Both OTA and NAS point out thatthe RCRA and Superfund legislationare intimately related. Because thematerials that are removed from Superfund sites are usually disposed of inlandfills, and landfills have inherentproblems no matter how well they aredesigned, we may be creating newSuperfund sites in the process ofcleaning up the old ones. Furthermore,landfills that are now active and runaccording to regulations could becomefuture Superfund sites because nospecific compounds are banned fromthem, and nearly all landfills will leakat some time in the future. OTA notes
proach," OTA writes, "would be toreward those who minimize futurerisks and costs to society through theuse of preferred aJternatives whichpermanently reduce the risks involvedin hazardous waste management."Table 2 shows an example of a proposed hierarchical fee system.
If the use of landfills were cut backby a large fraction, many new wastetreatment facilities would be required.OTA suggests that a federal loanprogram could be instituted to providelow-interest loans to finance these facilities. OTA also recognizes thatparticularly difficult wastes wouldrequire R&D efforts to develop economic alternatives to landfill disposal.It advocates government support ofprivate R& D projects in this area.Currently, EPA's R&D budget forhazardous waste disposal methods allots only 10% to the development ofalternatives to landfills. Tn addition,the total proposed 1984 budget for thedevelopment of all hazardous wastedisposal methods is 27% lower than thetotal in the estimated 1983 budget.
85
42
21
2111
o
Tax onliquid waste
(S/ton)
115
o
42
2111
Tax onsolid waste
(S/ton)Waste management category
Land disposal
Off-site:
Land disposal after treatment
Treatment
On-site:
Land disposal after treatment
Treatment
Recycling/reuse; used crankcase oil
Source: Minnesota Conference Report H.F. No. 1176, March 19, 1982.
under Superfund, there exist morethan 80 000 contaminated surfaceimpoundments (pits, ponds, and lagoons) in the nation. The potentialthreat of drinking water contaminationis posed by at least 90% of these, according to an unpublished EPA report.There are few regulations for thecontrol, monitoring, or cleanup ofthese sites.
The OTA study recommends anumber of regulatory changes thatwould close most of these loopholes. Itrecommends that the total exemptionfor hazardous wastes burned as fuel beended. It also suggests that regulatorycriteria should be established for hazardous wastes that do not fit EPA'scurrent definition of toxic but are implicated as hazardous by a substantialbody of scientific information (such asthose having significant levels ofdioxins or chlorinated organics). Inaddition, it states that certain hazardous wastes should be entirelybanned from landfills, surface impoundments, and deep wells. EPAshould be required to prepare a list ofsuch wastes, OTA reports. (On March17, 1983, EPA proposed two new rulesthat will close some of these loopholes.)
Other regulatory changes thatwould discourage the use of landfillsare also suggested. At present, Superfund is financed by a fee on chemical feedstocks, a so-called front-endfee. This fee provides industry with noincentive to reduce the volume of wasteproduced. OTA suggests that the Superfund monies be collected from atail-end fee-a fee on the amount ofwaste produced. This fee would not befixed for all wastes, but would varyaccording to the disposal method. "Theunderlying philosophy of this ap-
treatment system. OTA is especiallycritical of two risk assessment modelsdeveloped by EPA to apply to the Superfund law and RCRA. The assumptions on which these models arebased are so simplistic, OTA claims,"that their usefulness is questionable.For example, both models incorporatea concept that can result in unequalprotection of some segments of thepublic," such as those who live in areaswith a low population density.
OTA and NAS agree that manytechnically feasible methods of managing wastes are not being employedto their fullest potential. They recommend that regional centralized facilities for waste treatment be built. Suchfacilities would separate the wastesaccording to treatment class andmanage each in the most effective way.For small and medium generators, whomay not be able to purchase theequipment required for ideal wastetreatment, such facilities could providean economical and relatively safemeans of waste disposal. Examples ofsuccessful centralized waste treatmentfacilities in Europe, such as Kommunekemi in Nyborg, Denmark, aregiven. In Europe, landfills have beenalmost entirely phased out as a methodof hazardous waste treatment.
Changes in regulations
The OTA report (see Table 1)points out loopholes in current wasteregulations that leave certain hazardous wastes entirely unregulated andallow releases of hazardous waste tothe environment. RCRA does notregulate small generators of hazardouswastes-those that produce less than1 metric ton/yo Some of the wastesproduced by small generators arehighly toxic and are placed in sanitarylandfills where no monitoring at all isrequired to detect leaks into groundwater. Wastes burned as fuel are alsounregulated. These are consideredrecycled wastes and are not regulatedunder RCRA. Some of them containhighly' toxic materials that releasehazardous substances to the atmosphere when burned. A third group ofunregulated wastes is one that isomitted from EPA's definition. "Anumber of industrial wastes containingsignificant levels of dioxins, chlorinated organics or pesticides are notnow regulated as hazardous wastesand cannot be shown to be toxic byEPA's test for toxicity," the OTAstudy says. It goes on to note that inaddition to the 15 000 uncontrolledwaste sites (Superfund sites) classifiedunder the Emergency and RemedialResponse Information System, created
284A Environ. Sci. Technol., Vol. 17, No.7, 1983
William T. Carnall, EditorArgonne National Laboratory
Gregory R. Choppin, EditorFlorida State University
Reviews recent progress in plutoniumchemistry. Reports on fundamental research as well as applied environmentaland process chemical research. Coversphysical-inorganic chemistry andspectroscopy, solution chemistry andbehavior of plutonium in the aquatic environment, and separations chemistry.Includes introductory chapter by GlennT. Seaborg, Nobel laureate and codiscoverer of element 94 and numerousradioactive isotopes.
,CONTENTSPlutonium Chemistry: The Beginnings. MagneticProperties of Organometallic and CoordinationCompounds • Reaction of Pu Metal withDiiodoethane • Bis(,u-hydroxo)tetraaquadiplutonium(JV) Sulfate • Superconductivity andMagnetism in Metallic Pu Systems • Pu Halidesand Halogeno Complexes. Thermodynamics ofPu-Noble Metal Compounds. ThermodynamicAspects of Pu-O System • Hypostoichiometric PuDioxide. x-Ray Photoemission Spectroscopy.PuFs Gas Photophysics and Photochemistry •Measurement and Interpretation of Pu Spectra •Stability and Electronic Spectrum of CSPUF6 • PuSolution Chemistry • Pu(IV) Hydrous PolymerChemistry • Pu Ions and Products of H20Radiolysis. Stability Constants, Enthalpies, andEntropies • Photochemistry of Aqueous Pu Solutions • Behavior of Pu in Natural Waters. AquaticChemistry of Pu • Pu(IV) Ion in CarbonateBicarbonate Solutions. Ground-Water Composition and Pu Transport Processes • Overview ofPu Process Chemistry. Pu Process Chemistry atRocky Flats • Pyrochemical Processing of Pu •Pu Production and Purification at Los Alamos •Carbamoylmethylphosphoryl Derivatives • Appendixes: Round Table Discussion; Pu Isotopes
Based on a symposium jointly sponsoredby the Divisions of Nuclear Chemistry andTechnolo~yand Analytical Chemistry ofthe Amertcan Chemical Society
ACS Symposium Series No. 216480 pages (1983) ClothboundlC 83-6057 ISBN 0-8412-0772-0US & Canada $51.95 Export $62.95
Order from:American Chemical SocietyDistribution Office Dept. 241155 Sixteenth St., N.W.Washington, DC 20036or CALL TOLL FREE 800-424-6747and use your VISA or MasterCard.
that in 1985, (the year Superfund expires), more sites may need to becleaned up than are now listed underSuperfund as sites requiring attention. 'Also, the old Superfund sites may notbe adequately cleaned up even whenthey are treated according to regulations. Current laws for cleanup provideno specific technical standard, such asconcentration limits, for the extent ofhazardous waste removal.
Key to progress
No other issue affecting society hasresulted in as wide a gap between thebeliefs held by the public at large andthe beliefs of scientists who are expertsin the field. Progress in solving thehazardous waste problem rests in parton bridging this gap.
"Public attitudes toward hazardousindustrial wastes and their disposal,'"NAS notes, "include a number ofmisconceptions." ,There is a "generalbelief that hazardous waste generationcan be eliminated,. that waste discharges can be avoided, and that wastedisposal can be risk free. " The publicalso seems to believe that all hazardouswaste disposal technologies present thesame risks.
On the other hand, some of thepublic's concerns about siting hazardous waste facilities are valid. Undercurrent law, the community where thefacility is located bears the risk and issubject to potential damages from suchfacilities, although society as a whole
, enjoys the benefits (the products) associated with hazardous waste gener...ation. Another problem is that thepublic does not trust the government towrite good regulations or to enforcethem strictly. This concern may bepartially valid because hazardouswaste regulations may be inadequate,and enforcement during the past fewyears may have been lax.
Progress in siting hazardous wastefacilities and in developing and usingnew technologies will thus depend on'several factors. One of them is publiceducation to further an understandingof the technical issues involved. An..other is creating and enforcing consistent regulations to protect bothpresent and future generations.
- Bette Hileman
Additional reading
"Technologies and Management Strategies forHazardous Waste Contro}"; Congress of theUnited States, Office of Technology Assessment, Washington, D.C., 1983.
"Management of Hazardous Industrial Wastes:Research and Development Needs"; NationalMaterials Advisory Board, Commission onEngineering and Technical Systems, NationalResearch Council; National Academy Press:Washington, D.C., 1983
Charles G. Gebelein, EditorYoungstown State University
David J. Williams, EditorXerox Corporation
Rudolph Deanin, EditorLowell University
Focuses on the ways polymers can beused to construct efficient and durable solar energy systems. Points outthe advantages in cost, weight, andvariety of polymers and describes theproblems of photodegradation. Sections include general solar applications, polymer photodegradation insolar applications, and photovoltaicand related applications.
CONTENTSApplications and Opportunities • Economics ofSolar Heating Systems • Film and LaminateTechnology for Colfectors • Stability of Poly-merip Materials in the Collector Environment •Reduction of Solar Light Transmittance in Collectors • Optical, Mechanical, and EnvironmentalTesting of Collector Films • Protective Coat-ings and Sealants • Reactivity of Polymers withMirror Materials • IR Reflection-Absorbance ofFilms on Metallic Substrates • Adhes',ves inReflector Modules of Troughs • Solar Ponds andLiner Requirements • Flexible Membrane linings for Solar Ponds • Plastic Pipes for GroundCoupled Heat Pumps • Prediction or Photooxidation of Plastics • Photodegradation and Sorption and Transport of Water • UV Microscopy ofMorphology and Oxidation. Novel DiagnosticTechniques for Detection of Photooxidation •Photodegradation of Poly(n-butyl Acrylate) •Stability of UV-Screening Transparent AcrylicCopolymers • Deformation and Low-DensityPolyethylene Films • Luminescent Solar Concentrators • Encapsulation Materials forPhotovoltaic Modules • Encapsulant MaterialRequirements • Encapsulant Degradation •Vacuum Lamination of Photovoltaic Modules •Polyacrylonitrile as a Photovo/taic Material •Polymeric Phthalocyanines • Photophysics ofDoped Poly(2-Vinylnaphthalene) Films.Catalysis with Polymer Electrodes
Based on a symposium sponsored bythe Divisions ofOrganic Coatings andPlastics Chemistry and PolymerChemistry of the American ChemicalSociety
ACS Symposium Series No. 220510 pages (1983) ClothboundLC 83~6367 ISBN 0-8412-0776~3
US & Canada $51.95 Export $62.95
Order from:American Chemical SocietyDistribution Office Dept. 271155 Sixteenth St., N.W.Washington, DC 20036or CALL TOLL FREE 800...424·6747
