Document KRjnykrBrZ2gJ0Obpa7Xw5LOX

EPA's DIOXIN STRATEGY November 28, 1983 TABLE OF CONTENTS EXECUTIVE SUMMARY . Psrt .1 " Introduction .... 90. * I p3iitf s ,Dioxin Strategy ... .*. .o... .... 6 Study '"i'iv.rs ..#;, -'#. 0# *... ... ... .**.v -- &o Imp Ieme ntat ion of the Strategy a .*..... 7 Ei eld Sampling,, ,, # 0 .. T2 An alyt ica 1 Issvies , 13 -Ass essment of Oat a . #- / . ... .... 16 Regulatory Initiatives* **. . . IS Remedial Act ions at Contaminated Si tes................. .. 19 v|. Health and Environmental Effects f 2378-TCDD*....*..* .-.* 20 Other Dioxins and Dioxin-like Compounds. .... ... 22 ..Coord 1 fiaf 1 on *****. . ... *,******** *.. ***. ..,,* 24 Commun 1 1y Relations* .* *..*#**.**.. >* **0. 2^ Part 3;- Interim /Guidance for Tiers 1 and 2 ..* .*.... *.... 26 w-'.' ;y;: <Y ruxyrtc ' -"n , -.-b ; t : j- v y" xMS.j/ V:d c>A ..ftqxd .'~z ';,;.:p .c * ? ;. ~>f r a: 3 , ~i ;-c. '.: . :r i w , \:<,,y ;. .'T-.."irr i'w.v ar; .o: . : ( ' i f t - y d q a . l q dH..... r;., :;;f ^d'lvd .-qx.,'; r:;'.-j'':'.: fe:-\"g.-' :.v. _ ... -noe & :- v>'- .xr - . /* . , 'f :r<- ~ t -. i ' a x oc 9a :; i.a S j q e e c c i di : radi ;-d;. - d d ' - ' ^ x i:s- A-- ~v'?' i -.; i = c-t-o'-r , x ? r * ". d\...:? ' , . :-. .x - - X' jfi,: * .; .^DTiivV f e ` xf i ~ boq.xq - ait d " ; i& da> d :>*: 3;. id i eaciq ' pnd io3 : . ;1 :, v . - a - di';..i';;,Or 'rOi , :d^ci qx: : : /;; -_i vO .aiT;.. ,,, ?;nrx ..'v a y:'*< ^V*,; 'y'.'dad.: 'y d;x.. .va ity ::&rr- .:v./-. '. ' ..";..j.a,!;.dl h Etfracari,>:'; : ;De;? iaqq-es'.'Bdddd'V .d v-'nt ri ' */--a_ .V* - ' % < '`'I -% j b e c s t o v b -swfsftiM The strategy presented here provides a framework under which the u.Sv Environmental Protection Agency (EPA) will 1) study the extent of dioxin contamination and the associated risks to humans and the environment, 2) implement or compel, necessary clean-up actions at contaminated sites, and 3) furthef evaluate regulatory'alternatives to prevent future contamination, as well as disposal, alternatives to alleviate current problems. EPA will be investigating and taking appropriate response or enforcement actions at production, disposal, and processing sites where pesticides (including herbicides) contaminated with dioxin were or are being handled. In addition, the Agency will be sampling)other possibly contaminated sites as well as the ambient environment throughout the United States for the presence of dioxin. This overall investigation is in response to concerns raised by the increasing number of instances when environmental contamination by chlorinated dioxins has been documented. EPA will also continue its evaluations of human health risks associated with exposure to chlorinated dioxins and Of disposal and destruc tion methods. Although there are 75 different chlorinated dioxins, 2,3,7,8tetrachlorodibenzo-p-dioxin (2378-TCDD) is the one of primary concern because it is the most toxic dio.xin isomer, with the potential of presenting significant health and disposal issues. The 2378-TCDD isomer is known to be a contaminant of 2,4,,5trichlorophenol (2,4,5-TCP) when 2,4,5-TCP is made from tetrachlorobenzene. 2,4,5-TCP is used in the manufacture of various phenoxy herbicides, including 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) and Agent Orange, a defoliant herbicide used in Vietnam. The emphasis on 2,4,5-TCP and its derivatives is based on the fact that in nearly every place where 2378-TCDD has been found in the environment, it can be associated, if not definitively linked, to 2,4,5-TCP production or disposal sites. To facilitate implementation of the strategy, EPA has defined the following study tiers based on decreasing potential for 2378-TCDD contamination: Tier 1 .- 2,4,5-TCP production sites and associated waste disposal sites. Tier 2 Sites (and associated waste disposal sites) where 2,4,5-TCP was used as a precursor to make pesticidal products. Tier 3 Sites (and associated; waste disposal sites) where 2,4,5-TCP and its derivatives were formulated into pesticidal products, Tier 4 ojnbs't f<m'''-sirc'Si ,,.Tier. 5,;- ..Sites where pesticides derived from 2,4,S-TCP have ^eerrjknd are oeing used' or a commercial basis. Tier 6 .- Certain org$-ni' chemical and pesticide/manufacturing " ^VX^ciTiti'ss'Vh're'iihpropej: qualitycont.ro! <?n certain ... .... product ion-processes -could have _ resui-t'd in the format ion P*'f 2378"TCDD coiitam.rrfa:t:cd~produci:s waste ''3tre_amsi 5 r ' .* , , Tier 7 - ' Control sites' where contamination from 2378-TCDD is '.' > ' not suspecte.- :"" 4 The strategy calls for investigating" and tsteing any .'necessary respohsior enforcement actions at tier 1 sites and, eventually, at tier 2 sites. Sites in tiers 3-6 will also be studied to determine the probability of contamination at these types of sites. ' Sampling at sites in tiers 1-C will initially consist' of a .screening of areas most likely to be contaminated to determine if 2378-TCDD is present at the site. If it is, further sampling may include all media (air, Water, soil, stream sedimente,/Xish tissue) which are appropriate to define the extent of contamination and health risk. Sampling in tier 7 will be done in two phases in th first phase, EPA will collect multi-media samples at a number of control areas (e , g ., towns, sections of cities, 'rural areas) selected throughout the United States. During the second phase EPA will sample fish (and other aquatic organisms) at selected stations throughout the United States.-. -All sampling done under this strategy will follow prescribed ahalyticaT protocols. Another important aspect of the strategy is.to determine the potential health and environmental risks from exposure to 2378-TCDD; in different media. EPA, in conjunction- with Other appropriate fdral agencies such as the Veteran'sAdministtation (VA) and the various constituent agencies of the Department, of Health and Human Services (H H S ), (e.g., the Centers for Disease; Control (CDC), the Food and Drug Administration (FDA) , and the National Institutes for Occupational Safety and Health (NIOSH))-, will undertake research to Understand more fully the specific effects of 23.78TDD on humans and other species, and to dvlop techniques to determine actual risk given different levels' of. environmental contamination. X..'.W^.iX,''''l-h.^est.igtlons into the extent of human health and environmental risks from contamination by ,2378-TCDD proceed, EPA will also be evaluating different alternatives' fop containing and eventually disposing of soils `and wastes contaminated with 2378-TCDD. These alternatives include various methods of securing contaminated soil and preventing leachate runoff or percolation, extraction of dioxin from soils, for destruction of dioxins. ,-.qr photolysis Finally, th strategy .lists a numbef,--of '^rs^a|ch activities to define the potential human health and "environmental risks from dioxin isomers others t;hen l72^378-TvPD,r and. ,,.other. "dioxin- like" -Chemicals. Thee: ac t!y iole s include -,1 j' assessing !the toxicity of the -ether isomer;, . 2) -determining, .their specific sources, 3) evaluating tiie-ir environmental'fate".."and transport properties, 4) developing exposure and risk, ''assessments based on the above information, and 5) recommending appropriate control measures. To assist in these activities,, th sampling program for 2378-TCDD includes provisions to analyze for other dioxin isomers and "dioxin-like" chemicals when appropriate to the situation or the sampling site. , :. Regulatory Activities ` f; EPA's effort's to regulate dioxin in the environment began 'in 1973 when the Agency instituted proceedings to cancel the registration of the pesticide 2,4,5-T, based primarily on its, contamination. by 2378-TCDD. (Earlier, the (J.S. Department of Agriculture had limited uses of 2,4,5-T on food crops.) EPA terminated the cancellation proceedings in 1974, partly because the analytical chemistry techniques available at the time were not capable of measuring 2378-TCDD in food or the environment at the low levels which could pose a hazard. The Agency has since significantly i m p r o v e d .its analytical capabilities. In 1978, EPA initiated the -Rebuttable Presumption Against Registration (RPAR) p r o c e s s p r o d u c t s with 2,4,5-T. In 1979, based . O h a.;"'tyOy; of miscarriage rates in Alsea, Oregon (where 2,4,5t-T had.:ih^n:-sprayed on forest land) and extensive laboratory data demohstfating that 2,4,5-T, silvex, and/or 2378TCDD cause cancer and' adverse reproductive effects in test animals, EPA ordered e h emergehey suspension of 2,4,5-T and silvex use on forests, rights-ofhway^ pastures, home gardens, turf, and aquatic vegetation. Other,; uses were still being evaluated under the RPAR process. Dow Chemical Company appealed the suspension in federal court an^'.^dst.'-' In 1980, an EPA administrative law judge began- Oonso'lidj|:ed.. cancellation hearings on the suspended and nonsuspended uses of 2,4,5-T and silvex. These hearings were postponed :lh;:>t$81 to allow Dow and EPA to concentrate on settlement discussions. Other programs-haye also been involved in regulatory activities related to dioxin.: / under the Clean Water Act (CWA) , 2378-TCDD is listed as one of: the 65 compounds and classes of compounds which PA is. required to control in industrial, effluents. To date,' no national /disoharge regulations, have been issued for 2378-TcbD,.-..primarily, because it has not been detected in effluents. T h e Only time , it Oas Ibeen measured in efflunts -was when.-.EPA'.s. .. -, .................f t ,,..,,, ................................................ . ..... ,: Region-5 personnel' rmasurpd it at tb5e .5Q .parts, per quadrillion le<?l`in therDow -fif-l-ueste. (Analytical, problems may be one of ihereasons not otherwise detected.) EPA is working with the State of Michigan on dbvioping limitations for Dow's-prmb.tyR s'Under the Qlean Air Act , EPA is currently assessing the health 'impacts, of -2.37-3-TCDD as a hazardous air 'pollutant. As n lnterhTT'sten to-control the disposal of any wastes con taining '2378-TCDD (defined. as. wastes resulting"frm the production of";:2'V'4^5--feF^6r'^i^i:P^htihi;^e.id;etiyhtiyes.r;::r'';Svtbstahces, produced on equipaient that wa s previpus 1y used for the.production of 2,4,5TGP; or its.'pesticide derivatives) , EPA in 1980 promulgated a rule undel* th; Toxic Substances Control. Act (TSCA) which requires 'hy persons* intending .to move, or otherwise- dispose, of these wastes te notify EPA f its plans 60 days prior to initiating arty action. This:allows "EPA to review the plans, and ensure that the wastes ahre properly managed. In 1983, EPA proposed to regulate wastes containing any tetra-, panta-, and hexachlorodibenzo-p-dioxins under the Resource Conservation and Recovery Act (RCRA). This aet i o n w il 1 co-'et a wider range of wastes .and is designed to ensure that no future sites are contaminated with dioxin wastes. As this dioxin strategy is implemented and the data are assembled, analyzed, and reviewed, various regulatory options to prevent or control future 2378-TCDD contamination will be evaluated. Control options will include new applications of existing regulations as well as development of new regulations. Such actions as RCRA waste stream listings, CWA Section 307(a )(2) listings, TSCA Section 6 rules, and Clean Air Act hazardous pollutant listings, and alternative management options (e.g., prohibiting certain dioxin-containing wastes from land disposal), will be evaluated and recommendations to initiate regulatory actions will be made by appropriate program offices. Programs initiating regulatory actions should use the Dioxin Management Task Force as a steering committee for regulatory development. Management and Implementation of the Strategy The Assistant Administrator (AA) for the Office of Solid Waste and Emergency Response (OSWER) under the direction of the Deputy Administrator is responsible for implementing the strategy ';tneiudl:ng-';'*t.h-e:..vperiodic', reporting of progress to EPAVs Deputy Administrator. OSWER will directly manage the investigations arid responses for sites in tiers 1 and 2. . The Office of Water (OW) has been delegated responsibility for' the overall management of the studies within tiers 3-7. Within tiers 3-7, individual program offices will be responsible for developing, study plans relating to their programs; for example, the Office of Air, Noise and Radiation .(OANR) will prepare the study plan for tier 4. The AA for OSWER will have review and approval, authority for any ;; . , /' - iv : ; '/ . Pu . 1L.' HL policy or plans; developed: by oth^r EPA of fices that are implement ing , delegatedpgrtfans; of 'th strtepr ;OSWEH;wdl alis-o^h^e: oversight;;, responsibility for :.the;preparation of `external correspondence ,, testimony,;and; public statiftiehts . V-ji. This Strategy refiects Lwhat1' is- `currently known about dioxins! ... and presents.'a general' plan for irap1efien tat ion . Specif ic work plans for the various elements of the strategy are to be prepared by :the appropriate program officers in' conj unction, with the Regions . The actual detailed sampling- plans ;fbr ::sites :in; fiers:; 3-7 (exclusive of tier 4) will be prepared :by the Regional off ices in conjunction with the States and will be reviewed by the appro priate program of fice. Sampling plans 'for&'sites in *tiers 1- and .. 2 will be prepared by the Regional offices is conjunctilpn witt the Stats, CDG and NIOSH when appropriate. The individual work plans "are to be more specif ic;'than the; strategy and .t&e .detaiiecT sampling plans are, by nature, unique to-ach sampled site; they reflect what is known at the time of their preparation and the availability of resources. As time goes on and;more information is developed, the work plans and the sampling plans are expected to reflect the assimilation of new information and go through perhaps several changes. Thus, the strategy and the elements of v impleirjentat ion-- (e.g., work plans, sampling plans, disposal guidance )'will evolve as new information becomes available. OSWER has issued detailed interim guidance; (see Part 3 ,of : this document) to the regional offices on how: to proceed with investigations of the tier 1 and tier 2 sites. This guidance differentiates between the actual production sites (tiers 1 and 2) and the associated transportation, treatment, storage,' and disposal sites (referred to as tiers 1A and 2A in the guidance) . ", The basic approach outlined in the guidance is first to collect . detailed information on each of the sites from EPA and .State data bases and, if necessary, from site visits and employee interviews. Initially, any new field .investigations (screening) will be limited to tier 1 sites; new sampling work at sites in tiers 1A, 2, and 2A will be initiated after the information being collected has been evaluated by OSWER. Where the need for a clean-up response is identified, initial efforts are to be directed at getting potentially responsible parties to take .. appropriate action. . If .prompt and appropriate clean-up is not assured, by responsible parties, EPA will respond in a manner consistent with the National Contingency Plan and. the Regional work plane-^ or seek to compel response. The priority ..for taking either.gnforcemnt or response actions at. dioxin sites will be determined by .evaluating the seriousness ..pf the problem at the site relative to the problem at all other' sites whether .they include dioxin or not. V; tiers 1 and I Reipohie, Compensa'feioni and Liability Act (CERCLA)/.while funding^ ; fee t .. ?8 st tray' What ii refrre^to amination is detected bites the,data will forwarded OSWER for further evaluation, in implementation of the will require c l o s e c o o r d i - nation with a number of 'Other federal agencies, including FD A , CDC, NIOSH, .and ..others, OSWER is Responsible for ensuring that proper coordinatidn takes bn# of the key issues requiring ihteraoencv coordination 4is health and environmental effects research. OSWER, in conjunction with EP A 1s Of fice of Research and Development (QRD), is responsible for developing an initial list of research needs. Background - Toxicology Most of the available toxicological information on dioxins is. for the 2378-TCDD isomer, which has caused lethal and toxico logical effects in laboratory animals at lower levels than any other man-made chemical * However, both the lethal dose levels and the toxicological effects vary considerably among different animal species. EPA's Cancer Assessment Group regards 2378-TCDD as both an initiator and a promoter of cancer; this declaration is based on animal studies rather than data from humans. Based on its carcinogenic potency, ERA estimates that cancer risks to individuals exposed to soils or fish contaminated by 2378-TCDD could be significant under certain exposure conditions which are probably not widespread. Thus, estimates of national aggregate rfsits cannot be made with any degree Of accuracy until more data on exposure are collected. Background - Sources A number of the dioxins, including 2378-TCDD, are formed as inadvertent byproducts during the manufacture of certain organic chemicals, particularly chlorinated phenols. The 2378-TCDD isomer is formed during the production of 2,4,5-trichlorophenol (2,4,5-TCP), which is a basic chemical feedstock used to make several pesticide products including 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), silvex, hexachlorophene (a germicide), ronnel, and erbon. EPA scientists estimate that 80 to 95 percent of the 2378-TCDD which is formed during the production of these chemicals ends up in-the waste still bottoms from the toluene distillation step of 2,4,5-TCP product ion. Most manufacturers disposed of these wastes by placing them in landfills or incinerating them; however, some of the still bottoms may have been injected into disposal wells or transported for disposal by contractors. Other possible releases to the environment of 2378-TCDD from the 2,4,5- vi 7s/ ^ 7 TCP manufacturing process include wastewaters generated by contact cooling and product `Separaticin', and airt;emissions caused; by the venting of reaction;vessels. In addition, the 2,4,5-TCP product itself could'have been; contaminated with 2378-TCDD, particularly if it was manufactured prior: to the mid 1970's when reaction conditions began to be v more carefully controlled. Product contamination, therefore,, implicates sites where 2,4,5?TCP was used to make pesticide, products and, to a lesser extent, sites where those pesticide products were formulated for final uses.' Finally, sites Where these pesticide products were used could .also be contaminated. At the present time there are no known producers Of 2,4,5-r TCP in the United States; however, more than a dozen facilities have produced it in the past and may still be using contaminated equipment, A somewhat larger number of facilities were involved? in manufacturing 2,4,5-TCP based pesticides, and perhaps hundreds of facilities were involved in formulating these pesticides. (Part of EPA's strategy will be to refine the inventories of these facilities.) Finally, although past uses were more Wide spread, current uses of these pesticides are limited primarily to Arkansas and Louisiana rice fields, western rangeland, sugarcane fields in Florida, and certain rights-of-way as a result of the 1979 suspensions. However, it is difficult to predict the extent of future use of 2,4,5-T and silvex even in light of the 1979 suspensions. Combustion sources such as municipal and industrial waste incinerators and accidental transformer fires (where the trans formers contained a mixture of PCBs and chlorobenzenes) have been implicated as sources of 2378-TCDD and other dioxins, Generally, levels of the 2378-TCDD isomer from these sources have been relatively low; however, there is a potential for increased risk to populations in the vicinity of these sources. vii PART 1 INTRODUCTION Overview This strategy provides a- framework for actions that EPA, in coordination with other Federal and State /agencies, will be taking in response to concerns about health .risks from exposure to dioxin contamination in the United States. Since dioxiri Cont ami nation may ex ist in so i1> water,.and a i f s e v e r a l ' prog rams withiri EPA,/;at both the -headquart ef s and regional levels , are involved in this strategy; States are likewise atitively involved. There are two primary reasons which have led to the development of this ...strategy: (1) to provide a systematic technical approach in the investigation of sites, including both, chemical production facilities and waste sites, suspected of, beiijg contaminated with dioxin; and (2) to determine the extent of environmental contami-'nation pursuant to an FY 84 congressional appropriation specifically earmarked to conduct a "National Dioxin Study". ` Without this strategy, EPA's response to dioxin issues might possibly become "piecemeal,'' uncoordinated, and inconsistent, with priorities being established by special interest groups rather than from a perspective which Considers the -total situation. There are 75 different chlorinated dioxins, divided into 8 homologues (groups), each with different physical and chemical properties depending cin the number and location of chlorine atom substitutions. One of 22 isomers with four chlorine atoms, 2 )2,7,8-tetrachlbrdibenzo-p-dioxin (2378-TCDD), is of .primary cbncern because of its extreme toxicity in animals. Much information has already been collected on dioxins. Infor mation is still being; collected, and response efforts are being ,ta.ken fo reduCe human exposure to dioxins. However, unless these efforts are part; of a systematic national plan, inconsistent actions could occur, and information collected for one purpose might not be available to others who need it. The EPA dioxin strategy provides for intensive study of locations pg||fgtially. |contaminated with the most toxic of the dioxin i g M p , 2378-TCDD {about which the most is known> rboth oifJt-oki^PHy and sources) . The other, dioxin isomers will also be' llyalgjat^i. to determine whether they merit the' same intensive investigation. As a first step in this process, much incidental information will be collected on these isomers as part of the 378-TCDD effort. ' ' a In addition to the investigation and response activities called for in the strategy, the 2373-tCDD study will address five questions: 1) Where does it come from? 2) Where does it go? 3 ) What are the levels of concern? 4) Once it is in a medium at levels of concern, what can be done, about it? and 5 ) What can be done to prevent it from getting into the media? This strategy does not suggest that 2378-TCDD is the only toxic pollutant the Agency must address. It may not even be the most critical in terms of environmental and human health effects. Therefore, it is important that the individual program offices and the Regions implementing this strategy carefully recognize that their efforts on this contaminant may impact resources available for other problems and that resource decisions affectihg this strategy are to be made jointly with the program Offices and the Regions. Approach To implement this strategy, EPA has established seven cate gories (or tiers) for investigation and/or study ranging from the most probable tier of contamination (2,4,5-TCP production and waste sites) to the least. The functional components of implementation include: a. a comprehensive investigation leading to clean-up at the most contaminated sites ; b. a national study to learn more about the extent of . environmental contamination; and c. prevention of future contamination through development of control actions and regulations. This strategy ^addresses the most toxic of the dioxin isomers, 2378-TCDD, and lays out a plan to evaluate the other dioxin isomers to determine whether the same type of intensive investigation is necessary. Some initial screening f o r o t h e r isomers will be done at some of the sites, including control sites, being investigated for 2378-TCDD. One of the most important elements of this stra t e gy is that it be coordinated with other Federal agencies a n i ^ J ^ y ^ states, as well as- within EPA. The dioxin problem cannot addressed without active coordination of all these W r S u p s y 1 For example, FDA sets action levels and consumption advisories for fir and other consumables, CDC issues health advisories under CERCL and NIOSH sets limits on exposure in the workplace. In additio the Federal Emergency Management Agency (FEMA) coordinates t relocation of people during response actions under CERCLA, VA has developed a large body of expertise from dealing veterans on the Agent Orange issue. 2 States in conjunction with the Rgional offices will continue to have a m ajor responsibility in investigating and responding to individu al sites in tiers 1 and 2 as they do under CERCLA. The Agency hopes to involve each of these groups so that everyone can benefit from the others' experience, knowledge, expertise, and resources. . 2378-TCDD Questions 1. where does it come from? and 2,. Where does it go? For these two questions, EPA has set up seven categories (or tiers) for study. These include former production sites, waste disposal sites, incineration sites, formulation sites, etc. Under the overall direction of the Assistant Administrator for Solid Waste and Emergency Response (OSWER), individual offices will evaluate the sources with which they have the greatest familiarity. 3. What are the levels of concern? National criteria or action levels for 2378-TCDD have not yet been established. The respective program off ices are currently reviewing three dioxin hazard assessment documents (ambient water quality criteria for 2378-TCD.D; health assessment document for dioxins; and health and environmental effects profile for tetra-, penta-, and hexachlorodibenzo-p-dioxins) being prepared by ORD to determine the implications these documents haye on the dioxin strategy. Site-specific assessments have been made (the 1 ppb action level for soil at Times Beach, M o . ) , however, despite the lack of national criteria in order to assess the potential risk to humans at contaminated sites. In addition, the FDA has estab- , lished a "level of concern" for 2378-TCDD in fish. Until such time that further action levels are developed, EPA's SsWER, in conjunction with ORD, is responsible for developing a list of health and environmental effects research needs, included among these needs are standardization of hazard assessment infor mation, establishment of exposure scenarios, and development of a nomograph for converting from 2378-TCDD levels of contamination in all environmental media to estimates of upper risk limits for a var^*|;of exposure scenarios. This type of information is~ximpera^^for the development of action levels. 4. Once it is in a medium at levels of concern, what can be done about it? Available techniques are quite limited at this time. EPA's OSWER, in conjunction with ORD and the Dioxin Disposal Advisory Group, will be responsible for- pilot testing th more promising disposal/destruction techniques. . 5. What can be done to prevent it getting into the environment? Since there is no known current production of 2,4,5-TCP in the United States, future production of 2378-TCDD is likely to be limited to much smaller quantities from such sources as hazardous waste incinerators, transformer fires, and possibly municipal incinerators. These assumptions will be tested during the study. Under the appropriate regulations (FIFRA, TSCA), EPA will collect information on any future production of 2,4,5-TCP or its deriva tives that are used for pesticidal purposes. EPA is committed to regulatory actions that go beyond existing controls if the results of this strategy indicate that additional controls are needed. Other Dioxin isomers i " The Office of Solid Waste (OSW) has the lead -responsibility for developing a program to assess the other dioxin isomers and "dioxin-like" compounds. Activities to be defined in the program includes 1) determining the specific sources of other dioxin isomefs, 2) assessing their toxicity, 3) evaluating their environ mental fate and transport properties, 4) developing exposure and risk assessments based on the above information, and 5) recom mending appropriate control actions. Implementation of this, program is contingent upon available resources. Comparison of Risks In comparing the risks posed by 2378-TCDD with the risks attributed to other pollutants, it is important to identify and understand the components of risk. Simply stated, risk is a function of exposure to a chemical and the likelihood of some kind of harmful effect. One of the harmful effects can be cancer if it can be demonstrated that the chemical cau|(ttM^ancer in either laboratory animals or humans. The risk fro l ^ M ^ c i n o g e n e is usually "expressed in quantitative terms as alj^rbbabi^-ity value based on an exposure level. Other harmful effects may include, for example, heart disease and emphysema, although quantitative risk estimates for these kinds of effects a r e .no' usually expressed in probabilistic terms. It is also important to discern between individual risks aggregate (population) risks. Concern about individual focuses on the effect of a pollutant on increasing the ri particular individuals, without regard to the number of individuals involved. Concern abput aggregrate risk couples individual risks with the number of individuals involved, and thus deals with the number of cancer cases Which can be prevented. The derivation of cancer risks requires an assessment of th e . chemical's potency and the amount of the chemical to which the animal is exposed. Thus, understanding or quantifying exposure f is a necessary component in defining risk. Comparing the quanti i ;:;; . tative risks associated with 2378-TCDD with other chemicals is" confounded because of the lack of good exposure information. We are, therefore, left with a comparison that is qualitative based i i. i ** * '.>i rv on relative carinogenic potency, the amount estimated to be in the environment, and its behavior. The quantities of 2378-TCDD produced and released are much smaller than other pollutants of concern. On the other hand, its toxicity and carcinogenic potency are much greater. Thus, for example, the release of 2378-TCDD in past years is estimated to be about 30,000,000 times less than the release of benzene, 4,000,000 times less than carbon tetrachloride, and 130,000 times less than PCBs. On the other hand, carcinogenic potency of 2378- TCDD, based on animal data, is estimated to be 17,000,000 times greater than benzene, 5,000,000 times greater than carbon tetra chloride, and 100,000 times greater than PCBs. The bioaccumu *-V lation potential of 2378-TCDD is '20,000 times greater than that of benzene, 6,000 times greater than carbon tetrachloride., and ( 4 times greater than PCBs. Also, compared to benzene, 2378-TCDD W is very persistent in the environment. Based on what is known about 2378-TCDD release and behavior '* (i.e ., low levels of release, very persistent, and extremely potent), it is believed that risks to some individuals may be significant; however, the risks may not be widespread. Conse q u e n t l y , the aggregate risk to 2378-TCDD would probably not match that of such a ubiquitous pollutant as benzene (from gaso line) , a pollutant with a large level of release and a high potential for widespread human exposure, which is not very persistent and is not a very potent carcinogen when compared to ... 2378-TCDD. 5 O f;tli?. ?mu PART 2 EP A 'S DIOXIN STRATEGY 3:i, Vr.iP-iS, ;M;M3i S 3 333 Study Tiers / " ,.l^The following tiers (or categories of sources) are; defined based on a decreasing potential for 2378-t c d d '-d'fontami^'SjjS^ nation; they will -be addressedt by this strategy as-described;ji;ri| ^ the succeeding sections; '3'^, Tie-f 1 " ', -, ' - Current (if any) 'and former sites of '2.4^5-TCPlj^ production including sites where wastes were dijs-.** posed. The number of tier 1 production s i t e f v i s ,,,, estimated to be about 2 0 ; the total number**-,of V' sites to be investigated (production sites pTus.-< waste disposal sites) is not presently known. ' Tier 2 - Sites (current and former) where 2, 4 ,5-TCP .was used as a. precursor to make another chemical- product . (e.g. ,.hexachlorophene production sites,, 2,4.,5-T/ - and silvex) including sites' where wastes Were disposed'. The number of tier 2 production sites is estimated td be about 30, exclusive, of sites where wastes were disposed,, -- " ;- 'Tier 3 - Sites (current and former),, where. 2",4,5,-TCP;ivand its -p derivatives (e.g., silvex) were formulated' into.a pesticidal product. An ^example would be a site where 2,4-D and 2 ,4 ,57T were mixed to make Agent Orange. Tier' 3 also includes sites where formu- ' lating wastes were disposed. . ~ Tier 4 - Combustion sources such as: incineration of hazardous# and muncipal waste (including sewage- sludge); wirJJ reclamation facilities; internal combustion engines"; > home heating units (e.g., -wood burning ? industrial, fossil-fuel fired boilers; and ' tent combustion sources . such as PCB-1rans fires. The number of potent i,al`-sites^ in this tiex^ is estimated to be in the millions. Y " Tier 5 - Sites where;% 2378-TCDD contaminated pesticides,,._ been used or are being used on commercial, b'^ These areas include certain ,,tights-of-way,\ fields of Arkansas . and Louisiana, -p stu r^s'-'3 and western rangeland, sugarcane fields in and Louisiana, certain aquatic sites, a n d .-fore's^ (e.g., Pacifie northwest ). In addition - 6'S':.; , ( 1 animals which have been grazed on treated.''land and,'. fish from treated waterbodies may contain 2378-TCDD', Tier 6 * "2 v '' '/:"','i-K Sites where production of certain other '70nganic -, chemicals or pesticides may,ihave resulted ,>.thro'ugh ", improper quality control, in the formation ,of` 2378TCDD. The total number of production sites* in this tier is probably less than one hundred. Tier 7 - Control sites selected to evaluate the extent.- 0 f dioxin contamination in areas where manufacturing or extensive use of 2378-TCDD contaminated chemicals has not occurred. Information from these sites'will be used: (a) to compare with sites where 2378-TCDD is a known contaminant and, (b) to establish b a c k ground" levels of 2378-TCDD. ' , Implementation'of the Strategy Management and Funding 2. The AA for OSWER is responsible for implementing the over-' all strategy; he will report directly to the Deputy Administrator for purposes of this strategy. ^ 3. ,, The Xa for- OSWER will be assisted by three coordinating , \ groups: (1) th,e-Dioxin Management Task Force (DMTF), (2) the Dioxin Chlorinated Dioxin Wdrk Group, (CDWG) and (3) its sub-group, the Disposal Advisory Group {DDAG) formerly called .the Dioxin Task Force. Membership on groups (2) and (3) is currently set; member ship on'the DMTF shall be Office Director (OD) level individuals from Headquarters and Division Director level''' individuals from the Regions. , 4. The extent, of Headquarters and Regional membership on the DMTF shall b e 'determined by the AA for OSWER. 5. The Dioxin Management Task Force will assist gfehe AA for OSWER in implementing the overall strategy and function as a steering committee dealing with policy and resource issues. The Chlorinated Dioxin Work Group will continue to provide technical expertise as necessary and the Dioxin Disposal Advisory Group swill continue to make technical recommendations about, site-specific clean-up and disposal/destruction optins. - , ' Efforts conducted in tiers 1 and 2 will be managed directly by OSWER and funded under CEI^CLA authdrity*; r i< f ,, * f 7. -vB'i.forts-^^onduc^ecl in tiers 3 thru 7 have been delegated to O W , in; conjunction^ with appropriate program offices. In particular/ OAiJR will manage the development of a study plan for tier 4. ^ 8 . Management of tiers 1 and 2 will result in a comprehensive assessment of sites under CERCLA authority leading possibly to identification of responsible parties, enforcement actions and site clean-up. ; : 9- Th* program ... .fopL.7. constife.ufe&s,," . ...... Dipxifi Study1*yTM it ia a fed,..is^SiirigSa^^ nature of th# profrlembysaraplings respr*nte>arfe.ive f a c r ^ i ^ ^ h d - ::sited| It is not as comprehensive an investigation as that planned for tiers 1 and 2 which are thought to represent over 80 percent of the problem in terms of levels of contamination. In addition, any necessary followup actions at sites in tiers "3 thru 7 where contamination is found are likely to extend beyond two years. Tiers 1 and 2 1 1 . Sites (both manufacturing facilities ';;-:-'^hd:^'--waste:^:.-dis.; posai sites) in tiers 1 and 2 will be investigated following the attached guidance (Part 3 of this document) issued by OSWER. 12. The intrim guidance subdivides tiers 1 and 2 into* tier 1A and tier 2A which include the transport, treatment, storage, and disposal handlers or sites used by tier 1 and tier 2 facilities. A primary objective of the interim guidance is to set forth a proces for defining the dimension of the universe to be investigated in these tiers. 13. A second objective of this interim guidance is to make certain that the Agency's limited sampling resources are initially focused on the most serious sites. Regions are therefore directed to place pr-imary emphasis on tier 1 sites, and later, on tier 1 A sites. New- sampling at tiers 1A, 2, and 2A sites should be delayed, where it is not inconsistent with prior commitments, until the size of the universe for both tiers (1 and 2 ) are better defined. 14. The interim guidance directs Regional activities through several phases: an information collection phase, a field investi gation phase and a response phase. Also included in the interim guidance are Sections which provide guidance on community rela tions, enforcement procedures, and guidance on disposal alter natives . Tiers 3 thru 6 15. Because of the large number of sites to bienvestigated for 2378-TCDD in these tiers, sampling at every site is not practicable. One of the first steps will be to list, using avai1able- da t a , all facilities/sites in these tiers, Preliminary lists for tiers 3 and 6 have been developed by OW in conjunction with the other program offices and the Regions. These lists cannot be completed in final form until the results from infor mation collection forms have been received and all facilities can be assigned to their p roper tier. 16. The field investigations to be done at. tiers 3 thru over the next two years (FY 84 and 85) will be from a selected sample of sites based on a sample frame developed by OW, in conjunction with the Regional offices and EPA program offices (e .g ., OANR). The development of the sampling frame for tier 4 -- combustion sources -- 1 will be managed by OANR, with assistance, from ORD. They : will be supported by OSWER for designing the sampling frame for hazardous waste incinerators and OPTS for evaluating municipal waste incinerators. 6 17. The initial sampling to be done at tiers 3 thru 6 will be funded through an FY 84 appropriation Of $4 million which has commonly been referred to as "The National Dioxin Study"; this appropriation is directed to OW, which will allocate resources to the Regions and program offices based on anticipated sampling requirements. 18. OW, in conjunction with the other program offices and the Regions, has prepared a preliminary work plan availble for review for the "The National Dioxin study". This plan will describe the "universe" of sites in each of the tiers, the basis for site selection, tentative schedules, and arrangements for sample control. 19,. In developing the sampling plan for tiers 3, 5 and 6 , it is anticipated that multi-media samples will be taken at sampled sites / including samples of water, aquatic sediments, fish, soils, groundwater, vegetation, air, and waste streams (liquid, gaseous, solid) as appropriate. Once the preliminary sampling plan has been reviewed,, the Regions will then develop detailed sampling plans (e . g . , number of samples per media) for the initial sites to be sampled by March 1 , 1984. Once the detailed plans are reviewed by the appropriate program office, the Regions will be responsible for initiating field sampling. ; 20. Sampling at facilities in tier 4 -- combustion sources -- will include source sampling for air emissions and ambient air and will draw upon information already available from previous, sampling efforts (e.g., OPTS source sampling of municipal incine rators). Ambient samples of other media (e.g., fish, vegetation, and soil) may be taken as needed. OANR in conjunction with the Regions, is responsible for developing the sampling plan at tier 4 facilities. 21. Funds available for "The National Dioxin Study" are to be used primarily to establish whether sites in tiers 3 thru .6 are contaminated with 2378-TCDD. The object of the study is to learn more about 2378-TCDD contamination at sites in these tiers. If 2378-TCDD is detected at a site during the study, th data will be forwarded to OSWER for further evaluation. ..Also, there may be reasons, such as public requests and requests from state" governments, to sample sites in tiers 3 thru 6 that are not part of the sample design. Any activity at these sites will be in accordance with the interim guidance and coordinated with the appropriate program office, 22. It must be emphasized that, although sites found to be contaminated in tiers 3 thru 6 will be referred to OSWER for possible CERCLA action, such referrals do not necessarily imply immediate response, remedial actions or enforcement.. These referrals will have to be considered along with all of the sites in tiers 1 and 2 based on a schedule for response developed by OSWER. 23. While the Office of Water has been delegated the overall lead in implementing "The National Dioxin Study", the interpre-. tation of results and decision to take actions (e.g., remedies, and control"- actions) is the responsibility of the respective program offices. / :L 10 Tier 7 - Control Sites ! 24. Tiers 1 thru 6 represent sites or areas where contami nation with 2378-TCDD is either known or suspected. VA portion of the samples to be taken at these tiers will be ambient samples of suspected contaminated media, such as aquatic sediments, soils, fish, vegetation and groundwater. These samples will b e .useful in establishing the extent of outward migrationvpf 2378-TCDD from a source that is shown to be contaminated. ' .25. EPA believes it is equally important to assess the extent of environmental contamination of 2378-TCDD by taking ambient samples at sites not suspected of being directly influenced by known sources of 2378-TCDD. This may be considered an attempt to establish what many call a "background" concentration, and also serves to provide discrete data which address the general perception that 2378-TCDD contamination may be more widespread than previously documented. A portion of the special appropriation for "The National Dioxin Study" is specifically earmarked for this work. 26. Pursuant to this, the Office of Water, in conjunction with Regions and Headquarters program offices, will develop a sampling plan designed to determine the extent of 2378-TCDD contamination at various control sites. 27. The Sampling in tier 7 will' include two phases. The first phase will be to collect a number of soil, fish and stream sediment samples at about 20 control areas. These areas could be towns, sections of cities, or rural areas. These sites will fall into five categories: 1 ) chemical production areas (other than areas in tiers 1-6), 2) other industrial areas, 3) commercial/ residential areas, 4) agricultural areas, and 5) undisturbed areas. The initial candidate list of sites will be developed by OW based, in part, on recommendations by the Regions. Once the actual sites have been chosen, detailed sampling plans will be developed by the Regions in conjunction with the States. 28. The second phase of sampling in tier 7 will be to sample organisms in streams located throughout the United States, open waters of the Great Lakes, and estuarine waters. Stations will be selected which characterize conditions throughout the drainage basins. A preliminary list of stations has been sent to the Regions for their review. After review and final selection of stations, the Regions will be responsible for collecting the spcimens. Initial sampling will be whole fish composites of the same species, preferably bottom feeders. If significant contami nation is detected, analyses of fillets and stream sediments may be warranted. , 11 29. Detailed guidance (e.g., site selection, sampling and preservation methods) for tier 7 sampling will be issued by ow after the "National Dioxin study" plan has been reviewed. it is anticipated that this guidance will be available by December 31, 1933. . . V / , 30. Control sites; which show 2378-TCDD contamination will be evaluated by the Office of Water and the Regions to establish, if possible, the source of contamination. The data will also be forwarded to OSWER for additional evaluation. 31. This strategy acknowledges the current proposal by OPTS to measure dioxin (and furan) levels in human adipose tissue, although at this time this effort is judged to be outside the scope of sampling and funding pursuant to "The National Dioxin Study". Nonetheless, EPA recognizes the value of this proposal, therefore appropriate funding mechanisms will be investigated by OPTS. Field Sampling 32. Field sampling for all tiers, except tier 4, will be implemented through the EPA Regional offices. 33. Field investigations at sites in tiers 1 and 2 shall continue to use, as necessary, the Superfund contractors as well as the Technical Enforcement' Support (TES) contract. Wherever possible, responsible patties may be involved in conducting field investigations at the direction of the Regional Office in conjunction with states. 34. Field investigations at sites in tiers 3., 5, 6 , and 7 will be conducted by the Regional Offices employing those mechanisms they deem appropriate. For example, Regions may use contractors, their own Regional personnel, or may arrange for the states to perform the field sampling. Whatever choice is made, the individual sampling plans to be developed by the Regions for tiers 3, 5, 6 , and 7 are to indicate the arrangements for field sampling. 35. Sampling at sites in tier 4 shall be arranged by OANR. They may use contractors or a combination of contractors and Regional/SJtate personnel. 36. Whenever it is judged to be necessary, appropriate health and safety precautions shall be used during field sampling. This may require the use of personal respirators and other similar equipment. The individual sampling plans, prepared by the Regions, should indicate the need for such equipment. 12 37. Arrangements for laboratory analyses will be coordinated through the "Dioxin Sample Control Center". This center, for purposes of this strategy, will combine some of the functions currently being provided by OSWER's Sample Management Office (SMO) and OW's Sample Control Center, The, Dioxin Sample Control : Center will also be responsible for: (1) providing documentation of the analytical methods, including procedures for quality control and quality assurance and (2 ) entering the results into a central data system after they have been checked by the Regions and States. Specific details on these arrangements will be available for review by January 15, 1983. 38. This strategy reflects what is currently known about dioxins and presents a general plan for implementation. Specific work plans for the various elements of the strategy are to be prepared by the appropriate program offices in conjunction with the Regions. In turn, the Regions will prepare detailed sampling plans unique to each sampling site. Both work plans and sampling plans will reflect what is known at the time of their preparation and the availability of resources. As time goes on and more information is developed, the work plans and the sampling plans are expected to reflect the assimilation of new information and go through perhaps several changes. Thus, the strategy and the elements of implementation (e.g., work plans and sampling plans) will evolve as new information becomes available. Analytical Issues Sampled Media 39. Generally, multi-media sampling will be done at sites in tiers 1 thru 7, including, but not limited to, samples of soil, stream sediments, groundwater, surface water, ambient air, wastewater discharges, air emissions, fish, and other biological specimens (e.g., vegetation) as appropriate for the site. 40. The specific media to be sampled will, of course, be dictated by the type of facility or site in a particular tier. For example, sampling of waste sites associated with tiers 1 and 2 (tiers 1A and 2A) will likely be limited to soils, groundwater (if the site is near an aquifer currently used as a drinking . water supply), and surface water, if nearby. Specific sampling plans, developed by the Regions in conjunction with the States whenever appropriate, will spell out the' types of media to be sampled. 41. In certain circumstances it may be prudent to composite or pool samples in order to increase the sampling area without substantially increasing the number of samples to be analyzed.^ Compositing and pooling can, however, dilute the concentration' in the pooled or composited sample, therefore, care must be used in making this decision. ( 13 Detection Limits 42. Soil samples collected during screening at sites in tiers 1/ 2, 3, 4, and 6 will be analytically measured for 2378TCDD using methods that will result in a parts per billion (ppb) detection level. In certain cases sub-ppb detection limits can be achieved depending on the sample volume and the extraction efficiency. Follow-up investigations at contaminated sites may require soil analyses at the parts per trillion (ppt) detection limit, depending on the circumstances of contamination and potential for human exposure. 43. Soil samples collected at tiers 5 and 7 will be analytically measured for 2378-TCDD using methods that will result in a ppt detection level. Since these tiers represent areas where "background" levels of 2378-TCDD ar being evaluated, ppt level of detection is judged to be necessary. 44. Samples of stream sediments, fish, other biological specimens (e.g. , vegetation) and waste streams (liquid, gaseous, solid) will be analytically measured for 2378-TCDD using methods that will result in detection levels in the ppt range. 45. Samples of surface water, groundwater, and ambient air shall be of. sufficient volume to permit parts per quadri1 1 ion (ppq) level of detection. ' './*- V- Laboratory Resources 46. EPA's ORD and OPTS will provide analytical services for all samples collected in tiers 3 thru 7; control of these samples will be accomplished through OW's Sample Control Center. The analytical services will be managed by EPA's Environmental Research Laboratory in Duluth, MN, and will provide analyses of 150 samples per month for two years, the length of the "National Dioxin Study". Requirements for ppt and ppq analyses beyond the two years should be fulfilled by a sufficient number of contract laboratories that are anticipated to be in a position to do the required work by that time. 47. ORD will select appropriate sampling and analytical methods and QA/QC specifications for 2378-TCDD analyses in all tiers. These methods will be documented by the Dioxin Sample Control Center and circulated for review by January 15, 1983. Interim analytical methods and QA/QC procedures for 2378-TCDD analyses are described in an ORD document dated July `27, vl983. 14 48. EPA's OSWER will begin to develop the requirements for low detection level dioxin, analyses, including the necessary arrangements to certify/qualify contract laboratories and to provide for contractual mechanisms in order that Regions and States can have samples processed at,the ppt and ppq level beyond the two-year life of the ORD analytical commitment. 49. The Regions/States can continue to use the National Contract Lab Program as described in the Interim Guidance (Part 3 of this document) for sampling conducted at tiers 1 and 2 or they may use the ORD/OPTS analytical services for samples to be processed at the ppt or lower detection limits. Sampled destined for a contract lab should be controlled through OSWER1s SMO. During screening investigations, soils are to be measured at the ppb level of detection, and other samples (e.g., fish, sediments) are to be measured at the ppt level of detection. 50. Because of the large number of samples to be collected from tiers 1 through 7, the priorities for analytical work may at some point become an issue. The basic goal and the function of* the Dioxin Sample Control Center is to make certain that sampling, episodes will be consistent with the analytical pace and capacity so that samples are processed as quickly as they are collected. In the event a backlog occurs, samples from the lower numbered tiers (tiers 1 , 2, and 3) take priority. 51. This strategy recognizes that because the number potentially contaminated sites has not been enumerated, the total number of samples to be processed cannot be accurately estimated. Thus, samples collected from all seven tiers could conceivable outstrip current analytical capacity. It is important, therefore, to understand that if this happens, increasing laboratory capa bility may require additional resources and time. of Analyses for Other Chemicals 52. Analyses for other chemicals (e.g., other dioxins, furans, PCB's, chlorophenols) in addition to 2378-TCDD may be appropriate^ at certain sites, including control sites (tier 7). Mfefle th< ^ focuseg_jan_~222&%&._____ _ __ a 1lliByi>,a^ y ^ c a s o n T D i e in* order""to ' ma|^ resources., 53. The^_ decision to analyze for other chemicals will be made On a case-by-case basis by OSWER for sites in tiers 1 and 2 and the Office of Water in tiers 3 thru 7. Decisions will be made in conjunction with the Regions and coordinated through the respective offices. All analytical extracts processed under this strategy will be held for possible subsequent analysis for other chemicals and other dioxin isomers. -IS - 54. The analytical service to be provided by ORD of 150 samples per month is based Ion a scheme whereby tetra-class dioxins are initially analyzed. Should there be the need to analyze for other dioxins or other chemicals, the need must first be approved by the appropriate program Office since analyses for other than tetra-class dioxins will reduce the sample capacity of the ORD laboratories. For this re4 soh, sufficient sample volumes will be taken, to allow for subsequent analyses of other dioxins, furans, or other chemicals as appropriate. 55. The sampling plan to be developed by OSWER for the other dioxin isomers may include some of the same sites that will be sampled during the National Dioxin Study. Until such time that the sampling plan for the other dioxin isomers is developed, duplicate samples should be collected from the sampled sites of the National Dioxin Study. One sample will be measured for the tetra-class dioxin isomers and the other sample held for possible inclusion in the scheme to study the other dioxin isomers. Assessment of Data 56. The data obtained from sites sampled in tiers 1 thru 7 (exclusive of tier 4) will be assembled by- the respective Regions. The Regions, in conjunction with the program offices, will then prepare a report for each sampled site which summarizes available informat ion including the analyt ical results ; analyt ical results will be sent directly to th Regions from the Sample Control Center, This report, to be completed within one month from receipt of all the analytical data, should also contain recommen dations from the Regions on follow-up activities. 57. Reports on sites 'in tiers 1 and 2 will be forwarded to OSWER for review, comment, and assessment of follow-up actions. 58. Reports on sites in tiers 3 thru 7 will be forwarded to OW and OSWER for review and comment. Reports on sites in tier 4 -- combustion sources -- will be prepared by OANR with assistance from the Regions where the combustion sites were sampled. 59. Sites in all tiers that are determined to be contaminated with 2378-TCDD will be further evaluated by OSWER to determine the need for further sampling and/or response. As stated pre viously and- emphasized again, referring a site to OSWER does not necessarily imply immediate response, remedial actions or enforce ment. The timing of actions must be consistent with the degree of contamination and potential health risk of the site when compared to other contaminated sites. 16 60. Whenever it is determined that there is sufficient sampling to demonstrate that 2378-TCDD contamination constitutes a potential public risk, the Regions in conjunction with OSWER, as described in the Interim Guidance, will immediately notify the appropriate officials including, but not necessarily limited to, state officials (particularly health officials) and CDC. 61. CDC and FEMA will continue to work through the OSWER program office as defined in the Executive Order pursuant to CERCLA and redelegation agreements pursuant thereto. 62. The Regions are initially responsible for compiling and reporting the data which will be collected pursuant to this dioxin strategy. To effectively manage the data and facilitate the review by the Regions and the program offices, centralization of the data is essential. Pursuant to this need, EPA's STORET system will be used to store and retrieve the dioxin data which will be collected from all tiers. The Dioxin Sample Control Center will, after first reporting the analytical results to the Regions, enter the results into STORET. Access to the data will be limited based on guidelines developed by the Sample Control Center in conjunction with- the Regions and -the program offices. 63. The development of site-specificresponse actions or enforcement at contaminated sites will be managed by OSWER in conjunction with respective Regions and other Federal/State agencies involved with the site. If appropriate, the Chlorinated Dioxin-Work Group and its subgroup, the Dioxin Disposal Advisory Group shall review disposal/destruction related activities at these sites. 64. OW in conjunction with the other program offices and the Regions will assess the extent of 2378-TCDD contamination in tiers 3 thru 6 . The basis for this assessment will be developed from the information collected at the sampled sites and must be consistent with the overall sampling frame. 65. OW will also evaluate the datacollected at tier 7 sites. This information, plus the site specific information from sampling tiers 1 thru 6 , will be the basis for determining the extent of environmental contamination of 2378-TCDD. This overall determination shall be made jointly by OSWER and OW in conjunction with those-program offices that have major assignments in the strategy and the Regional Offices. 17 6 6 . Pursuant to the special appropriation for "The National Dioxin Study," OSWER and OW in conjunction with the other program offices and the Regions will prepare a report which documents the extent of environmental contamination based on the information obtained pursuant to this strategy. This report shall be forwarded to the Deputy Administrator and made available to the public by December 31, 1985. Regulatory Initiatives 67. As stated previously, this strategy is being developed to study the extent of dioxin contamination, implement necessary remedial actions at hazardous sites, and evaluate regulatory actions to prevent future contamination. EPA has a strong commitment to regulatory actions if necessary to ameliorate existing problems or to prevent future ones. The very nature of 2378-TCDD, however, makes regulatory development an especially difficult process. 6 8 . EPA is committed to publishing the three dioxin hazard assessment documents recently reviewed by a.peer group of scien tists in Cincinnati, OH. While the documents are not regulatory actions per s e , they can have regulatory implications for the affected program offices. The affected offices are to carefully evaluate these criteria documents and develop, where appropriate, regulatory initiatives that are consistent with this dioxin strategy. 69. As the data are assembled, analyzed, and reviewed, various regulatory options to prevent or control future 2378-TCDD contami nation will be evaluated. Such actions as RCRA waste stream listings, CWA Section 307(a)(2) action, TSCA Section 6 rules, and Clean Air Act hazardous pollutant listings, for example, will be evaluated and recommendations to initiate regulatory actions will be made by appropriate program offices where the data justify regulations. Equally important will be the evaluation of current permit authorities (e.g., underground injection, ocean disposal) to assess whether changes are necessary. The Agency will explore utilizing the Dioxin Management Task Force as a steering committee for regulatory development related to dioxin. 70. On April 4 , 1983, EPA through its RCRA program has proposed adtiing the following waste streams to EPA's list of hazardous wastes: (a) The production and manufacturing use of tri-, tetra-, or pentachlorophenol and intermediates used to produce their derivatives; - 18 - (b) The manufacturing use of tetra-, penta-, or hexachlorobenzenes under alkaline conditions; (c) The production of materials on equipment previously used for the production or manufacturing use of materials listed under (a) and (b) above; and (d) Discarded unused formulations containing tri-', tetra-, or pentachlorophenols, or discarded unused formulations containing compounds derived from these chlorophenols. Under RCRA, the Agency has broad authority to regulate all aspects of hazardous waste management (i.e., generation; trans portation; treatment/storage/disposal). The proposed rule for active facilities will impact the response by the Agency to the contamination sources in each of the tiers. Remedial Actions at Contaminated Sites 71. Based on the information obtained and analyzed from sites sampled in tiers 1 thru 7, short and long-term clean-up strategies will be implemented or compelled at those sites where dioxin con tamination is judged to warrant action. This judgment shall be made by OSWER with technical assistance from CDC, the Chlorinated Dioxin Work Group, ORD, the Regions and the affected States. Cleanr up activities will proceed in accordance with the interim guidance and the National Contingency Plan. The priority for taking either enforcement or response actions at dioxin sites will be determined by evaluating the seriousness of the problem at that site relative to the problem at all other sites whether they include dioxin or not. 72. Presently, alternatives which appear to be most suitable for uncontrolled sites are listed below: A. Secure soil in place -- in situ soil fixation, subsurface perimeter grout curtain, impermeable cap, diversion of surface runoff, resident relocation from immediate area and monitoring. B. Consolidate and secure soil -- ; removal of soil to secure landfill; or containment of soil in a concrete vault, possibly on-site. C. Incineration -- following excavation and transportation, a size reduction process is required before incineration. D. Solvent Extraction -- solvents would be used to extract dioxin from the soil into a soluble form. Several different technologies could then be used to destroy the dioxin. 19 ii `' w s m iA vn:;-^'* '.j*';:-V.' 'V' y,;t,v.- .-a / W l in conjunction with ORD and the Dioxin Disposal Advisory '-Gifeiap, (DDAQ,)',/will 'be responsible for pilot testing the more^ppomi^jthg disposai/best ruction techniques. A specafic ^ .research agenda shall 'be developed by December 20, 1984. '7 4 .'/Several important, questions need :to be addressed through pilo't- etigdi's;before these alternatives can be fully evaluated. .For'.expl/p^./' r destroy dioxin, the treatment technology must first brgak th'dipxin/soil particle bond. In doing so, partially treated residues, or contaminated materials which may be released during pcocess^ing',; have the potential to spread contamint ion. Therefore,ORO^ will consider including a sorpt ion/desorption study On contaminated soils as part of its research agenda to determine dioxin.release rates. While thse treatment technologies may present the ultimate solution to, contaminated media, they could present significant health risks during processing. Thus, during the pilot testing.p h a s e , the potential for further contamination must be assessed-..'. 75. Based upon the success of. the pilot testing phase, OSWER staff in conjunction with ORD and the DDAG/-will recommenO full field validation projects to the A for OSWER. Upon a p p r o v a l O R D will implement the full field validation studies in conjunction with the Region where testing is't.o occur. Full fi/bld validation work should commence by July 1985. 1 76. The results of pilot testing and full field validation will be reported to O S W E R "':T.he/"e'SUts will be used to support specific guidance concerning the alternatives for clean-up given specific conditions of contamination and exposure. This guidance will be used in deciding upon final clean-up options at specific contaminated sites. Health and Environmental Effects of v378-TCDD - 20 - 4 78. Som&i'6 :'the studies to be conduJjjcF'. are 'short-terra _in. nature andC,appropriately managed by EPA; gt'he.r,'types., of- studies, are longer-term and are byon'd '.th:'. pu'rview^'^-lfA. Thus, inte-r^ agency 'coordination in this area is essential For purpose's--of intra-agency coordination , OSWER,~ in conjunct ion-with ORp.an.d-. the' program offices, will develop a list by 'February 15, 1'9`84 'of specific health and environmental.-effects, -`research' needs. that will assist EPA in implement ing the elements",;--, of-., this strategy ; This list will also be used to assist in coo^'i/nation with other Federal agencies. ` "*- ` 79. The following short-term activities are* to- be -conducted by ORD with assistance from CDC and the affected'-program. offices': A. Using best data at hand (carcinogenicity and repro ductive effects) ORD will continue to coordinate hazard assessment techniques used by*EPA' in making site-specific risk assessments. ^ - B. ORD in conjunction with the CDWG.will establish exposure scenarios to estimate, exposure under various conditions likely to be encountered at tiers 1 thru 6 . A report is to be completed by July' 1984. ,C. ORD will develop a nomograph-for converting from 2378-TCDD levels of contamination in environmental media to estimates of. Upper risk limits for a variety of exposure scenarios; a final product will be completed by .July 1984. ORD wil provide guidance to the Regions and States on use of exposure nomographs; this guidance will also' be available by July 1984. 80. The respective offices will review the three dioxin hazard assessment documents being prepared by ORD and determine the implications these documents have on the elements of this strategy. This review is to be completed by January 1, 1984. In addition, OW and OPTS will work with the FDA and the u.S. Fish and Wildlife Service in assessing the relationship between the FDA action levels for 2378-TCDD in fish and the proposed ambient water quality criteria. Any conflicts between the two numbers are to be identified and resolved, if possible, by March 1, 1984. 81. EPA's ORD will study the bioavailability and uptake mechanism of sorbed 2378-TCDD. ORD will also investigate the transport and transformation processes (bibaccumulation and bio- mag'nification) of 2378-TCDD in fish, sediments, and plants for use in food chain models and establishment of acceptable levels. ORD will develop a time frame for these activities and identify resource needs by February 1, 1984. 21 82. The following research items are judged to be of suffi cient importance to the strategy that they should be specifically identified in any inter-agency meetings that are conducted to initiate health research: A. Understanding the pharmacokinetic mechanism of 2378-TCDD induced toxicity to determine differences between species in response to 2378-TCDD. B. Understanding arid developing the toxicological and analytical relationship between 2378-TCDD and "2378-TCDD equivalents" in complex mixtures for more rapid and less expensive determinations of 2378-TCDD levels and effects. C. Conducting epidemiological studies at contaminated sites to provide better information of risks for regulatory decisions. Thi*s work will help establish the cause/effect relationship of 2378-TCDD to humari disease. Other Dioxins and Dioxin-like Compounds 83. A number of haiogenated compounds related to dioxins are thought to be almost as toxic as 2378-TCDD. They therefore have the potential for causing significant exposure and risk problems. Among these compounds, the haiogenated dioxins and furans with chlorine or bromine atoms at positions 2,3,1, and 8 , and with at least one hydrogen atom on the dioxin or furan structure, are of special concern. These haiogenated dioxins and dibenzofurans are inadvertent, by-products of a number of production processes involving haiogenated phenols, and are thought also to be created in the course of combustion of a variety of haiogenated aromatics. The production and use of pentachlorophenol, and of other halophenols and of their drivtes, and of polybrominated biphenyls and biphenylethers, are also of concern. In addition, combustion of these compounds could, under certain conditions, create "dioxin-like" compounds. 84. As part of this strategy's approach to dioxin the Dioxin Management Task Force, in conjunction with the Chlorinated Dioxin Work Group will develop by January 15, 1984, a work plan to study the other dioxin isomers and "dioxin-like" compounds. The acti vities to be included in the work plan are: 1 ) determining the specific sources of other dioxin isomers and dioxin-like compounds, 2) assessing their toxicity, 3) evaluating thei-r environmental fate and transport properties, 4) developing exposure and risk assessments based on the above information, and 5) recommending appropriate control actions. Implementation of the work plan will be dependent on resource availability. 22 85. Existing information, and chemical structure analysis, will be used to investigate the sources of these compounds. First priority will be given to investigating the contribution from combustion and chemical manufacturing sources. Following source identification, a sampling plan will be developed to evaluate these suspected sources. The sampling plan will identify the processes which ate also sources of 2378-TCDD; thus, much dual sampling will be avoided. 8 6 . In order to take advantage df the sampling effort being conducted for '2378-TCDD, the Regions will collect sufficient sample volumes to analyze for both 2378-TCDD and the "dioxinlike" compounds at those sites sampled in tiers 1 through 7. 87. As part of the development of an inter-agency program, EPA's ORD will coordinate with the other Federal agencies in developing a research program by April 1984 which addresses the toxicology of the other dioxin isomers and the "dioxin-like" chemicals. Additional toxicity data are needed, especially for possible carcinogenic, reproductive, and teratogenic effects, and bioavailability of the halogenated dioxins and dibenzofurans. 8 8 . During FY 84, ORD will work with CDC, the U.S. Fish and Wildlife Service, and other Federal agencies to develop analytical protocols tb measure "dioxin-Idke" chemicals in biological tissues, waste emissions, and.environmental media. Interim protocols will be completed by September 1984. 89. ORD will explore the development and validation of bioanalytical techniques for estimating the toxicity of complex mixtures containing 2378-TCDD and "dioxin-like" compounds. It is expected that such methods will reduce the need for the expensive and resource-intensive isomer-specific analysis of the mixtures associated with combustion and chemical processes. 90. ORD, in conjunction with the Chlorinated Dioxin Work Group, will develop and apply methods to predict the fate, persistence, and bioaccumulation potential of dioxins in the environment. These efforts will begin in PI 84 in conjunction with the development of the sampling program discussed above. The results of these analyses will be combined with the source asessments and toxicity studies to provide interim exposure and risk assessments for the other dioxin isomers. Interim assessments will be available by September 1986. 91. As sources of other dioxins and "dioxin-like" compounds are evaluated, OSWER will, if appropriate, develop regulations under RCRA in order to ensure the proper disposal of wastes from such sources. As a first priority OSWER will promulgate the regulations proposed on April 4, 1983, for the regulation of process wastes containing tetra-, penta-, or hexachlorinated dioxins and dibenzofurans, as appropriate. 23 Coordination 92. Coordination between the various agencies is a crucial element necessary to answer questions that have been raised about dioxin exposure, environmental effects, and risk. In the area of health research (toxicological studies and epidemiological studies), the federal health and safety agencies under h h s (e.g., DC, NIOSH, and FDA) , VA, and EPA should work closely together. The-' governments of Canada and Italy, in particular, should also be involved in the coordination of efforts pursuant to this strategy. OSWER will have overall responsibility for coordination. 93. To help achieve effective inter-agency coordination, OSWER will develop a plan which will frame the issues to be addressed by the agencies and, in relationship to E P A 'S strategy, investigate various mechanisms (e.g., the Department of Health and Human Services' committee to coordinate environmentally related programs) to secure interagency coordination. This plan will be available by March 1, 1984, for review by the Deputy Administrator. , 9 4 . EPA recognizes the importance of the States in effectively implementing this strategy. Accordingly, the Regions are to coor dinate with the States in gathering information on specific sites, in developing sampling plans and collecting samples and in devising the appropriate response. It is especially important to encourage States' initiative in any reSpons.e efforts that may take place at a contaminated site, including direction of respon sible private party action. Such coordination will minimize duplication and maximize resource availability. 95. It is very likely that the results of EPA's dioxin strategy will point out the need for more work in a number of areas, especially in the area of source characterization and control technologies for the other dioxin isomers. since funds are not yet available for additional work, requests for additional funding should be developed through the appropriate EPA and other agency budget processes. Community Relations 96. EPA recognizes the importance of dealing with the public on such a ^sensitive issue as dioxin. Indeed, even the sampling at uncontaminated sites (tier 7) will likely generate local apprehension and questions. To communicate effectively with the public, each Region should appoint one individual to handle community relations relative to this dioxin strategy. 24 97. The Regional community relations official will provide updates, as needed, to local and State governments following the community relations plan that is to be developed pursuant to the OSWER interim guidance for tiers 1 and 2. 98, The AA for OSWER or his designate in conjunction with EPA's press office will be the focal point at headquarters for public relations. .m' 25 PART 3 INTERIM GUIDANCE FOR TIERS 1 AND 2 EXECUTIVE SUMMARY Introduction The Agency has been developing an overall strategy for responding to the public health risks associated with dioxin contamination. The major components are: 1) A national study of selected sites to estimate the extent of dioxin contamination (the "study" component); 3) Identification and coordination of research and regulatory initiatives to prevent contamination (the "regulatory" component); and 3) Development of appropriate response measures at contami nated sites (the "cleanup" component). The EPA dioxin strategy provides for intensive focus on the most toxic of the 75 dioxin isomers .-- >' 2,3 r7>8-tetradhlt>?r'od.i;benzo-pdioxin (2378-TCDD) . The other di'oxin isomers, which have"different physical and chemical properties, will be evaluated as part of the strategy to determine whether they merit the same intensive investigation. This section provides interim guidance on the third major component listed above: the identification of TGDD contaminated sites and the development of appropriate response measures. For the overall strategy, the Agency has identified a seven tier hierarchy of sites based on an estimated decreasing potential for 2378-TCDD contamination. The focus of the cleanup component will be initially on the most serious sites, and this guidance sets up a controlled, structured approach for working down through tiers 1 and 2 to identify 2378-TCDD contaminated sites. The national study will utilize the data being collected in the cleanup component, but will focus its resources on tiers 3. through 7. Of course, any site discovered to be contaminated with 2378TCDD in tile national study or otherwise will be referred for appropriate cleanup response. For the cleanup component, the 2 tiers of concern are: Tier 1 - Current, if any, and former sites of 2,4,5-TCP production. ::ft; - 26 Tier 1A - Transport, treatment, storage, and disposal (TTSD) handlers or sites used by tier 1 facilities. Tier 2 - Sites, where 2,4,5-TCP was or is used as a precursor to produce another chemical product (e.g., hexachlorophene, 2,4,5-T, silvex, etc.) Tier 2A - Transport, treatment, storage, and, disposal (TTSD) handlers or sites used by tier 2 facilities. Due to the manufacturing processes involved, it is estimated that 80-95% of the 2378-TCDD produced in this country is associ ated with tiers 1 and 1A. While it is believed that there are approximately 20 facilities in tier 1 and 30 in tier 2, there is no accurate count of handlers or sites in tiers 1A or 2A. Accordingly, a primary objective of this guidance is to set forth a process for defining the dimensions of the universe to be investigated. A second objective of this guidance is to see that the Agency's limited sampling resources are initially focused on the most serious sites. Regions are directed to place primary emphasis on .tier 1 sites, and later on the other tiers (tier 2) consistent with the Regions' work plan and with the approval of the AA for OSWER. Additionally, it is recognized that some Regions are already sampling at sites in tier 2. The demand that this sampling has placed on the national lab capacity and Superfund support contracts is considerable, in order to focus on the potentially more serious sites in tier 1A, and to maintain resources for other Superfund work, the Agency has made a decision that new sampling at tier 2 sites should be delayed, where it is not inconsistent with prior commitments, until the size of the universe for both tiers is better defined. Then, the Agency will make decisions regarding the best way to apportion laboratory capacity, support contracts and technical resources. This interim guidance sets forth certain other decisions which will have to be coordinated with OSWER in order to maintain a coherent Agency approach and to control the resource demands nationally. Approach The Regions' activities at the sites will involve several phases. The basic approach, explained in more detail later in this interim guidance, is as follows: Information Collection . 1. Consolidate Regional and Headquarters data bases to identify tier 1 and 2 sites. 27 2. Collect information for known tier 1 and 2 sites to begin identification of tier 1A and 2A facilities and .'s i t e s . 3. Depending ori the results, arrange site visits, employee interviews,' and other evidence collection necessary in the field. Field Investigation 1. Sampling at tier 1 sites should begin during the infor mation collection phase. 2. No new. sampling should be initiated at tier 2 sites until the results of the information collection process are analyzed, and the Agency determines how it will proceed. The same is true for transportation, treatment, storage and disposal handlers or sites associated with any of the 2 tiers. Response Activities 1. If 2378-TCDD contamination requiring a cleanup response is identified, direct initial efforts at getting poten tially responsible parties (PRPs) to take appropriate action (e.g., remedial investigation, emergency response). 2. If necessary, develop a Superfund cleanup response. Detailed Guidance Whenever possible, the Agency will work closely with the States and encourage them to be the lead agency as it does throughout the Superfund program. After the Agency has conducted an initial screening of the sites, it will look to potentially responsible parties (PRPs) to undertake Remedial Investigations (RI). Due to resource demands placed oh the Agency, the Agency has made a management exception to current policy by allowing PRPs to under take Remedial Investigations. The scope of any remedial investi gation conducted by a PRP will be incorporated into an adminis trative order. Community Relations Plans Community Relations Plans (CRPs) must be developed for each site in accordance with the guidance issued to the Regions on May 9, 1983 with modification as necessary for consistency with this interim guidance. 28 Information Collection The Office of Waste Programs Enforcement (OWPE) is. in the process of identifying current and former 2,4,5-TCP manufacturing sites (tier 1 ) and current and former manufacturers who purchased 2,4,5-TCP as a feedstock in pesticide production (tier 2). The compliance monitoring staff of the Office of Pesticides, and Toxic Substances Enforcement (PTSE) will assist OWPE in identifying potential 2378-TCDD dioxin sites by' providing accesss to their FATES computer system from which information on pesticide pro duction can be obtained. Further, OPTSE in conjunction with the Regions (Air and Hazardous Materials Division) will summarize and provide information from the Toxic Substances Control Act (TSCA) Section 6 dioxin inspections. Various program and enforcement offices in Headquarters are being asked to compile information and coordinate it through OWPE. The results of the survey will be made available to the Regions. m The Regional Superfund program and enforcement offices should confer with the Regional Pesticides, Toxic Substances and the Resource Conservation and Recovery Act (RCRA) program and enforce ment offices to obtain information on production, transport, treatment, storage, and disposal of 2,4,5-TCP wastes from facil ities identified by OWPE and other facilities the Regions may identify. The Regions should notify OWPE of the results of their document search by September 6 , 1983. This information will be used by OWPE to complete its categorization of sites and facilities into the appropriate tiers. OWPE will provide this "revised categorization" to the respective Regions by September 19, 1983, and will update this information as necessary. In order to gain more informaton on potentially contaminated 2378-TCDD sites the Regions will issue CERCLA 104/RCRA 3007 information request letters by September 30 to all tier 1 and tier 2 facilities identified by OWPE and the Regions. Recipients of the letter will be given 30 days to respond. The letters will request information on the amounts of waste generated and disposed, current and past disposal practices, including disposal site locations and waste haulers, and other pertinent information that may be needed to support an enforcement or Fund-financed response action. Use of enforcement actions under RCRA 3008 for inadequate responses to the information request letters should be initiated -when appropriate. The Regions are advised to remain firm on the 30-day deadline for responses to the information request letters. Extensions, if granted, should only be granted for good cause shown and should not exceed two weeks. 29 Most responses, even with a two week extension, should be in the" Regional offices by November 15, 1983 . The Regions should review.the responses and provide to OWPE, by December 15, 1983 , the following: - : 1) List of facilities that- complied with the request; 2) List of facilities; thdif failed to respond; 3) List of additional sites, including transporters, treatment, storage, and disposal facilities identified in the responses; and 4) A Regional plan for further investigative and response activities for each site. After compilation and review of all available information, the Region will determine if additional information gathering through follow-up site inspections, interviews with current and former site employees, responsible party searches, and/or title searches is needed. The Regions should also consider the use of a trained investigator to compile information and assist in investigations. ? Preliminary Investigation Phase (Screening) This portion of the guidance explains how to conduct a syste matic investigation of facilities. Tier 1 sites will -be screened first in order to focus efforts on sites posing (potentially) the most urgent and widespread public health concerns. By December 5, 1983, the Regions should implement and provide to OWPE a screening program for confirmed tier 1 sites. When OSWER deter mines that the resources are available nationally, tier 1A, 2, and 2A sites will be; investigated following these same procedures. During the preliminary investigation phase an initial screening of tier 1 facilities shall be* conducted to determine if 2378-TCDD is present at the site. If it is present, further remedial inves tigation or endangerment assessments shall be conducted as des cribed in the response phase of this guidance, initial screening of tier 1 facilities will be conducted by EPA or States concurrent with information gathering. Once the" Region has identified the tier 1 facilities targeted for preliminary investigation, it will devise a screening program for collection of a limited number of environmental media samples at these sites. In Regions where several tier 1 facilities are to be screened, an inspection scheme should be developed to help management set priorities and schedule investigations. In general, where currently operating facilities have been targeted for, sampling, the Region .should look to FIFRA, TSCA, RCRA, and/or CERCLA for authorities to conduct recprd inspections and/or collect environinental mddia samples-. In addition, the Regions should address compliance with all applicable..rules and regulations. Field Investigation Procedures , ; The following procedures for screening sites for potential 2378--TCDD contamination should be, instituted for tier 1 sites. 1) Develop and implement an initial site sampling plan (screening program using the protocols and procedures developed by EPA/ORD and the Centers for Disease Control > (CDC) to sample the most probable locations of dioxin contamination at the site or in the immediate vicinity) . Site inspection schemes should be reviewed with OWPE Regional Coordinators - Compliance Branch. During this round of sampling, limit the number of samples taken to only those which are necessary to determine if dioxin is present. States should be advised by Regions of the site inspection schemes. For active industrial sites, CDC should be contacted to coordinate with the National Institute for Occupational Safety and Health (NIOSH) for ; further sampling guidance. If there are people living in the area, the State health officials and CDC should review all sampling protocols from the beginning. CDC should be> .contacted through its: staff person in each EPA Regional Office. 2) Initial field investigations must employ EPA chain of custody procedures, document control, site safety plan procedures and Quality Assurance/Quality Control procedures.* ~ 3) Analysis for 2378-TCDD in soil will be conducted using state-of-the-art low resolution GC mass spectrometry methodology and appropriate detection limits. Analysis for 2378-TCDD will be performed using high resolution GC mass spectrometry methodology in enviormental media other than soil. Qualitative analytical screening for other dioxin isomers should also be considered by the Regions ,at sites where there is reason to believe that other dioxin isomers may be present. The Regions should contact the National Contract Lab Program in order to schedule sample analysis as early as possible. These samples should be labelled as tier 1 - 2378-TCDD *. Guidance for QA/QC is available from the Office of Research and Development. 31 V. samples in addition to any of the identifiers used. . (Coordination should be through the Regional Envirpnmental Services Division (ESD) Directors). 4) If the initial sampling, results: indicate 2378-TCDD is present, and response action is to be pursued through eitherenforcement or Fund-financed activities, the proce dures set forth in tjie Response Phase of this guidance should be followed as appropriate. All phases of response must be in accordance with the National Contingency Plan. The priority for taking either enforcement or response actions at dioxin sites will be determined by evaluating the seriousnes of the problem at that site relative to the problem at all other sites whether they include dioxin or not. Regional Workplan The information obtained from the field investigations should be used by each Region to develop a Regional workplan for tier 1 sites which initially determines whether or not a contaminated site will be addressed through Fund-financed activities or enforcement authorities, and projects a schedule for further action. Workplans should be submitted to OSWER by March 15, 1984. These workplans will be reviewed by OSWER in light of the national demand for resources and analytic laboratory capacity. OSWER will consult with the Regional Offices on any adjustments to the workplans based on the dimensions of the national situation. Response Phase Response actions, which are consistent with the Region's workplan and the approval of the AA for OSWER, will be initiated at a site when the analytical results of the preliminary field investigation (screening) confirm the presence of 2378-TCDD and the Region determines that the situation warrants response. In evaluating whether) or not to take a response action at a site, the Agency will consider criteria such as the following: the location of the site, the site's use, the demography, etc. If technical assistance or expenditure of funds from other Federal agencies is needed, a Regional Response Team (RRT) meeting should be -convened. The RRT will serve as the coordinating mechanism within the Federal government and for Federal/State cooperation. In addition, because the RRT serves as the coordi nator for inter-agency actions, it can also become the focal point1 for communications with the local citizens and the press at a site. - 32 - Enforcement Procedures (See Figure 2) To support possible enforcement response- actions at tier 1 sites where 2378^TCDD contamination has been confirmed through initial screening, additional information gathering may be needed to supplement the material gleaned from the CERCLA 104 and RCRA 3007 information request letters and from FIFRA/TSCA inspections. In the Regions, the Air' and Hazardous Materials Division will determine the sufficiency of information collected and have primary responsibility for compiling information from' local, State, and Regional sources. At the Region's request, OWPE will compile information from computer systems such as FINDS in the Management Information Data Systems Division and from the various program and enforcement offices to support an enforcement response action at a particular site. Once the potentially responsible parties (PRPs) have been identified, notice letters will be issued apprising PRPs that EPA has conducted or will conduct planning or response actions at the .site to determine both the nature and extent of the dioxin contamination. The PRP will be offered the opportunity to undertake the necessary assessment and response actions at the site, and will be apprised of possible liability under CERCLA for injunctive relief or cost recovery in the event Superfund action is taken. If the PRPs. choose to undertake the necessary response actions at the site, the Region should, depending upon the evidence available, issue an administrative order on consent In order to gather additional data and direct the appropriate response measures (e.g., CERCLA 106, RCRA 3013, RCRA 7003). Where PRPs decline to undertake the necessary remedial investi gation activities the Region will pursue, afder consultation with the Office of Waste Programs Enforcement (OWPE) and the Office of Enforcement Counsel Waste (OEC-Waste), one of the following options: 1) Issuance of a unilateral RCRA 3013 or CERCLA 106 order to obtain the information necessary to conduct a feasibility study? 2) Initiation of a Fund-financed removal action; 3) Initiation of a Fund-financed remedial investigation/ feas-ibility study (RI/FS)? or 4) Initiation of an enforcement-funded endangerment/ alternatives assessment. The option selected will be dependent upon such variables as the complexity of the case, severity and imminence of hazard, the number of sites needing response action, availability of Super fund and/or enforcement dollars, and availability of personnel. 33 If Option 1 above is selected and the PRP complies with the order, then EPA will perform the feasibility study. If the PRP chooses not to comply with the order, then the Region should pursue Option 2, or 3, or 4. If opt ion 2(:;is" chosenV the proce dures out li ned for "removals ") in the Response Sect ion below, should be followed. For option 4, an endangerment assessment must be performed by the Region. in addition, an endangerment. assessment may also be necessary for options 2 and 3 if a cost recovery action is to be taken. This assessment will .examine the nature and quantity of the dioxin or any hazardous materials,~ exposure pathways, human and animal populations exposed or poten tially exposed and the actual or potential risks and effects associated with the exposures to the hazardous materials. At this point, CDC should be notified of the information contained in the endangerment assessment and be asked for a health assess ment or advisory. CDC will coordinate with NIOSH for active work-related situations. The endangerment assessment along with the subsequent alternatives assessment are considered to be the critical components of the enforcement strategy, and are necessary to ensure successful prosecution of an enforcement action under administrative or judicial statutory authorities. Upon completion of the Fund-financed RI/FS or the enforcement financed assessments, the Region will have 60-120 days to nego tiate an agreement with the PRPs for response action. If an agreement can b; reached, it will be embodied in an administrative order or a consent decree pursuant to 106 and/or 7003. If an agreement cannot be reached, the Region will p u r s u e , after ^consultation with QWPE and OEG-Waste, one of the following options : _ 1 ) Issuance of a unilateral administrative order pursuant to 106 and/or 7003; or 2) Initiation of a judicial action pursuant to 106 and/or 7003; or 1 *. 3) Initiation of a Fund-financed response action followed by a 107 cost recovery action. If Option 3 is selected, then the Region will initiate a cost recovejry action pursuant to 107 for reimbursement of expenditures under Superfund for site planning and response and other expenditures. Cost recovery actions will be conducted in accordance with existing procedures and policies. Dioxin sites identified for action by States may require Agency overview in the form of technical support for enforcement actions or response actions. In certain cases, actions may / ./. j ' ! 34 '-''Involve.'/joint \fedei`a%':EPA and state efforts. Depending on the sUccess:V'..p:'f'. State enforcement action, direct EPA involvement may be necessary. - Fund-Financed Response :If the initial sampling (i.e., the limited sampling performed as step #1 of the Field investigation Phase) results indicate that dioxin is present, and the response is to be Fund-financed, then the Agency must decide if the situation warrants a removal action. Regions must recommend removal actions, with required documentation to the Assistant Administrator for OSWER. CDC should be consulted in case a health assessment or advisory is heeded. If EPA believes temporary relocation is warranted, it must ask the Federal Emergency Management Agency (FEMA) to make such a determination. It is possible that either or both short-term and long-term cleanup activities may be necessary at a site. (If the site is going to need long-term or "remedial" work, then the site needs to be scored in accordance with the Hazard Ranking System for ranking and placed on the National Priorities List (N P L ) , if appropriate.) Additional investigation, planning and design work for long term activities can be performed while short-term cleanup activities are being performed. If work other than removal action is needed, the following activities should take place: 1) A more detailed sampling effort should be conducted at the site, setting up the sampling, locations in a grid network extending beyond the facility boundaries. Environmental media other than soil should also be sampled when appropriate. Once again, CDC and/or NIOSH should be involved in this process. Sample protocols and analysis schedules should be reviewed with OERR. As noted above, the Region should contact the Sample Management Office of the National Contract Lab Program in order to schedule all sample analyses and mark samples "Tier 1-TCDD". Coordination should be through the Regional ESD Directors. 2) Once the results from this second sampling are obtained, EPA should again request a health advisory or assessment from CDC. Based on CDC's recommendations, EPA must decide if temporary or permanent relocation should be considered for persons residing in the vicinity. As noted above, FEMA makes the determination for temporary relocation during removal activities. If temporary relocation is contemplated during remedial actions, EPA makes the determination (under a recent redelegation of authority from FEMA) that it is necessary and FEMA 35 impleinehts the determiriatidn;. EPA also has the responsi bility for making the determination concerning permanent relocation, and FEM iniplements it 3) If further response activities are warranted, and the site has been proposed for inclusion on the NPL, feasi bility study and design-work should be initiated, followed by additional construction. Separate guidance is attached concerning the short-term and long-term technical options for destruction and disposal of dioxin which are currently available or being developed. In addition, information is included regarding the notification procedures to be followed for the transport -or disposal of dioxin. Technical Assistance The Region should consider using their FIT and TAT as well as FIFRA, TSCA, and Water inspection program resources in the infor mation collection and initial screening phases. The Superfund contractors (REM/FIT and TAT) as well as the technical enforcement support (TES) contract should be used to support field investi gations , data analysis and development of feasibility studies for 2378-TCDD contaminated sites. Water quality program monitoring resources may also be useful In the investigative mode for fish and water sampling. Environmental media samples taken during the field investigations can be analyzed by the Superfund contract laboratory program. If the capacity of these laboratories is exceeded, other laboratories available to the Region through contractual arrangements, ORD or the Environmental Services Division, may be employed after consultation with OERR's Technical Support Division. Financial Assistance The States can / use the money allotted to them through the CERCLA/RCRA 3012 .program to investigate sites thought to be contaminated with ' 2378-TCDD. For example, if the State has targeted 100 site inspections in their application, and now wishes to inspect 20 2378-TCDD sites. The States can perform activities at the 20 2378-TCDD sites as part of their established g o a l . This would simply reestablish priorities for the States. The following activities can be funded with these grants : preliminary assessments, site inspections, responsible party searches, discovery, and site inspection followup. For more information about this source of funds, you can refer to the Federal Register Notice of February 7, 1983 and the PA guidance issued on March 8 , 1983. | | "'v - ^ ^ 'y \ A - 36 - JPEListof245-TCP mufactureraani245-TCP >stlcideDerivative mufacturera jj piauns I II Reviewoflocal.state andfederalfilesby HQRegionandState U 104/3007Letterato CUPEListofFacilities TIER1 M2an4uf5a-cTtCuPrersof TIERU FIFRAInosrpection T9CAInsoperctlon/Sonpling SuperfundScreening > SuperfundScreening TTIFESRDf1acilitiesof ~ * Cpornisourlttowittahki0n6gWER furtheraction TIER 2 FIFRAInspection Siteswhere2,4,5-TCP wasusedasaprecursor or jAyTSClInspection/Saropling cthoempircoadlucperaodnuoctther- isS* SuperfundrScreening % "Superiti*!Screening> TIER 2a TTSDfacilitiesof l"* TIER 2 > ConsultwithOGUER priortotaking furtheraction 2,3,7,8-TCDD present -> Response Action 'and (see Fig. 2) gAaddtihteiroinnaglfoirnfeonrfmoarticoenment - piunrtpeorsveisewse.rge.spofnilseisbleseapracrhty search .- No 2,3.7.8-TCDD Present ------->|No Response Action} f 3013 A.O. for RI -------- > or S3013/106 A.O. for RI/FS/RD/RA or S106 and/or S7003 Consent Decree for RI/FS/RD/RA 3013 Unilateral a .O.^-j-- ^ for RI or `Fund-Financed RI/FS and/or Renoval Enforcement-Financed f-- Endangerment/Alternatives Assessment* * FIGURE 2 ATTACHMENT I DISPOSAL GUIDANCE Background Although a significant amount of dioxin-related research work has been published, most is related to the toxicity or destruction of dioxin in a solubilized form. This is rarely applicable to the conditions existing at most Superfund sites. These sites are often characterized by a variety of contaminated soils, gravels, and other materials, for which there is little available infor mation to use in developing a technically sound prediction of dioxin's behavior in the environment, its containment efficiency, or treatment effectiveness. Due to dioxin's known toxicity and hazards* to personnel, the scientific community has been reluctant to conduct controlled investigations of dioxin's environmental behavior outside of the laboratory. These risks, plus the high cost of analytical testing, have also limited rigorous studies of uncontrolled dioxin releases to a few instances. Furthermore, only at Seveso, Italy, and Snytex have significant investigations been conducted into treatment alternatives for dioxin-contaminated soil. At these and the other sites, the contaminated soil was eventually contained in a landfill or is presently in an interim storage facility, awaiting the development of technologies related to dioxin-contaminated soil. Remedial Action Alternatives Considered Over 40 possible treatment processes and over 500 sources of information were considered in the initial screening of alterna tives for the feasibility study Minker/Stout dioxin site in Missouri. The treatment processes were screened on the basis of 1) state of development, 2) health and safety risks, 3) process complexity and constructability, 4) reliability, and 5) cost. Six remedial alternatives were selected for a detailed eval uation. Alternatives A through C rely on the principle of containment to reduce dioxin exposure which, due to the demon strated insoluble nature of dioxin in these soils, centers around immobilizing the contaminated soil particles. Alternatives D through F rely on the principle of treatment to reduce dioxin level, in addition to containment of the treatment residue. In reality, each treatment alternative is a two-stage process, involving soil extraction (thermal or solvent), followed by a destruction process. Contaminated soil has several unique characteristics that make the application of any of the treatment alternatives a challenge. Among the special requirements are: 39 0 The need to process a wide range of contaminated materials, e . g . , rocks, clay, roots, and other materials on-site. 0 The irequi'rement that the remedial alternative be capable of processing all contaminated' material. Combination of reme dial alternat ives for various types and concentrations of contaminated material were not considered. 0 The use of Level C or higher personnel protection for all soi1 handling and treatment activities. 0 The potential listing of 2378-TCDD as a RCRA waste, which will significantly impact storage, trarisporttion, monitoring, and treatment requirements. If residue tests and other limitations do not enable a delisting of the treated residue, there would appear to be little .cost incentive to treat the soil prior to containment i,n a fully permitted secure landfill. The following six remedial alternatives were selected for a detailed evaluation at the Minker/Stout site. Alternative! 0, E , P and the possible fixation portion of Alternatives A and C have significant technical unknowns that warrant pilot testing to better demonstrate their application to dioxin-contam'nated soils. Alternative B and the ,remainder of Alternatives 'A and C are highly site-specific and do not warrant pilot testing but may need additional site testing. Alternative A -- Secure Soil In Place This alternative would secure t h e so;il ih place and prevent public site access. This would likely involve insitu soil fixation and securing the site with a subsurface perimeter grout curtain, an impermeable cap over the contaminated area, and diversion of surface runoff. Permanent resident relocation and house demolition would be necessary within the sites and for any additional house holds inside an .undertermined buffer zone. A longterm site monitoring and maintenance program would be necessary to monitoring the ground w a t e r 'and conditions in the surrounding environment. Alternative B -- Consolidate Soil On-Site , This alternative would remove the contaminated soil and consoli date it into one area at the site. Due to the varying soil depths, unknown site hydrogeology, and the need for a positive liner and leachate collection system, a double-lined, above-grade concrete vault would be used to contain the contaminated soil. Permanent resident relocation and house demolition would be necessary within the sites and for additional households.inside a buffer zone. A long-term site monitoring and maintenance program would also be required. 40 - Alternative C -- Secure Soil Off-Site This alternative would remove and transport the contaminated soil to a secure hazardous waste landfill for disposal. in accordance with the April ,4, 1983, Federal Register, the Agency is. currently proposing the addition of dioxin wastes to the RCRA regulations. If this proposed .rule is promulgated, the design and operation of each landfill disposal facility would need to be thoroughly evaluated before dioxin could be added to the landfill's permit. The removed soil volume and up to a foot of additional fill would be added to restore the site drainage and to cover any fugitive traces of contaminated soil. The site would be reland scaped and the houses rehabilitated to completely restore the area. Alternative D -- Incineration This alternative would involve the direct thermal extraction and destruction of the 2378-TCDD-contaminated soil. The contami nated soil would be stabilized on-site or removed to a concrete ^ault, or other storage facility, where it would remain while the incineration process was pilot tested and developed for this particular contaminated soil. The low levels of soil con tamination, required high destruction and removal efficiency, and widely varying soil characteristics will likely expand the 'state-of-the-art of incinerator technology. A significant permitting effort could be necessary for the pilot tests and for the siting of a full-scale facility. Fol lowing the permitting process and the construction of the facil ity, the soil would be transported to a size reduction and handling process, and then to an incinerator. The incinerator particulate and soil residue would- be transported to a secure landfill site, unless extensive testing allowed the residue to be delisted under RCRA. Alternative E -- Solvent Extraction This alternative would extract the dioxin from the soil with a solvent, concentrate the solvent, and then destroy the dioxin in the solvent. The contaminated soil would be stabilized on site or removed to a concrete vault where it would Remain while the solvant extraction process as pilot tested and developed. A significant permitting effort could also be necessary for the pilot tests and the siting of a full-scale facility. Following the permitting process and the construction of this process, the soil would be transported to a size reduction and handling process, and then to the solvent extraction process. The resulting contami nated solvent would be concentrated, with the concentrate under going .degradation and incineration. The incinerator particulate and;the soil residue would be sent .to a secure landf ill site, unless extensive testing allowed .the; residue to be delisted. Alternative F -- Storage While Awaiting Development of. Emerging Technology -A. . / This alternative would allow for the development of emerging technologies other than incineration and solvent extraction. The contaminated soi1 would be removed and stored unti1 such time* as emerging technologies (such as supercritical water reactors, wet air oxidation, fluidwall reactors, and biological degradation) could be pilot tested and evaluated for their ability to be competitive with existing technology. Today, these technologies are not developed sufficiently to be used commercially'' for this type of hazardous waste. All of these technologies have several major technical hurdles to overcome before they can be considered viable. There is a risk that these emerging technologies may never become cost effective for these soils and, therefore, a contingency .plan would be necessary, should a research and devel opment program not proceed as quickly as planned or be unable to demonstrate an acceptable alternate technology. Long and Short-Term Control strategy Preliminary testing .indicates that three Minker/Stout soil samples subject to EP toxicity tests all showed leachate containing no 2378-TCDD above the 1-ppt detection limit. In its current soil matrix, 2378-TCDD appears to be water insoluble, as well as non volatile arid, therefore, soil particle movement is necessary to spread the contamination. Containment technologies are based on the dioxin-so.il binding characteristic and focus upon the restriction of soil particle movement. These technologies can be used as a short-term interim solution when coupled with treatment technologies for future processing, or as'a long-term remedy. * When dioxin contamination above 1 ppb is detected, a short term control strategy should be immediately developed. This short-term strategy should focus on containing the contaminated soil and preventing airborne migration and surface stormwater erosion. Public access to the site should be limited. Resident relocation will be based on health advisories or assessments issued by the Centers for Disease Control and determinations by the Federal Emergency Management Agency or EPA that relocation is necessary to protect public health in accordance with a recent redelegation of authority from FEMA. A monitoring program should be designed to determine the extent of surface and subsurface. migration. If the site cannot be controlled on a short-term1 basis, then excavation and temporary storage will be required. EPA has proposed the listing of a number of dioxins (including 2378-TCDD) as hazardous wastes under the RCRA regulations. Cur rently, however, the disposal of 2378-TCDD contaminated wastes (including soils) is covered by TSCA (40 CFR 775.197). These regulations have governed the manner in which temporary storage has been provided at several sites including: . Denny Farm, Missouri. Syntex Verona, Missouri Vertac Jacksonville, Arkansas Saugett, Illinois Love Canal/Hyde Park, New York Temporary storage may be undertaken by the responsible party, or as a Fund-financed immediate removal or as a remedial action. ... ' . . As sites ere discovered and actions planned, the. TSCA mechanism can be utilized for technical review of any actions which might be taken. For further information contact Dr. Donald Barnes, Chairman, Chlorinated Dioxin Work Group at 382-2897. Contaminated sites will require extensive sampling to deter mine the extent and severity of the( problem and to assess the performance of short-term controls. The destruction of dioxin in soil will require the development and pilot testing of technologies and should be considered as a long-term (greater than two years) control strategy. To destroy 2378-TCDD, treatment technologies must first vaporize or solubilize the 2378-TCDD from soil thus breaking the dioxin soil bond. In doing so, partially treated residues, or contaminated materials released during processing, have the potential to spread contamination via any one of the exposure routes (water, air, and soil) with highly mobile soluble, volatile, or particulate forms of 2378-TCDD. While treatment technologies may be considered the ultimate solution, they could entail significant health risks during processing. State-of-the-art methods will be necessary to mitigate the exposure hazard to workers, the public, and plants and wildlife. The control of dust, treatment emissions, water contact with soil or treatment residue, must be an integral consideration when evaluating"destruction technologies and will have to be considered as part o f "any future pilot testing program. - 43