United States
                   Environmental Protection
                   Agency
Prepared by the Office of
Wate    ' ions and Standards
and . j -  - of Solid Waste and
Emergency Response*.in io-ijunction
with the Dioxin Strategy Task Force
November 28, 1983
Washington, DC 20460
&ERA         Dioxin Strategy    Odd 0766000

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          United States Environmental Protection Agency
                          DIOXIN  STRATEGY
   Prepared by the Office of Water Regulations and  Standards
      and  the Office  of Solid Waste and  Emergency Response
       in  conjunction with the  Dioxin Strategy Task Force
                         November  28, 1983
                       Washington,  DC  20460

U.S. Environmental Protection Agency
Region 5, Library (PL-12J)                             U.S. Environmental Protection Ac^-"
77 West Jackson Boulevard, 12th Floor                    Great Lakes National Program Offio,
Chicago, IL  60504-3590                                   .,    GLBPO Library

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                      EPA'S DIOXIN STRATEGY




                        November 28, 1983
TABLE OF CONTENTS








EXECUTIVE SUMMARY




Part 1 - Introduction	  1




Part 2 - EPA's Dioxin Strategy	  6




     Study Tiers	  6




     Implementation of the Strategy	  7




     Field Sampling	 12




     Analytical Issues	 13




     Assessment of Data	 16




     Regulatory Initiatives	 18




     Remedial Actions at Contaminated Sites	 19




     Health and Environmental Effects of 2378-TCDD	 20




     Other Dioxins and Dioxin-like Compounds	 22




     Coordination	 24




     Community Relations	 24



Part 3 - Interim Guidance for Tiers 1 and 2	 26

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                        EXECUTIVE SUMMARY

   The strategy presented  here  provides a  framework  under which
the U.S.  Environmental Protection  Agency  (EPA)   will  I)  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)  further 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,  2,3,7,8-
tetrachlorodibenzo-p-dioxin (2378-TCDD)   is   the   one  of  primary
concern because  it  is  the most  toxic  dioxin  isomer,  with  the
potential of presenting  significant  health  and disposal  issues.

   The 2378-TCDD  isomer  is known to be a contaminant  of 2,4,5-
trichlorophenol (2,4,5-TCP) when  2,4,5-TCP   is  made  from tetra-
chlorobenzene.   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.

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    Tier 4 -  Combustion sources.

    Tier 5 -  Sites where  pesticides  derived from 2,4,5-TCP have
              been and  are being  used  on  a  commercial  basis.

    Tier 6 -  Certain organic  chemical and pesticide manufacturing
              facilities where improper quality control on certain
              production processes  could  have  resulted  in  the
              formation of 2378-TCDD  contaminated  products  waste
              streams.

    Tier 7 -  Control sites where contamination from 2378-TCDD is
              not suspected.

   The strategy calls for  investigating  and taking any necessary
response or 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  1-6  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 sediments, fish
tissue) which are appropriate  to define the extent of contamination
and health risk. Sampling in tier 7 will be done in  two phases.  In
the 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 analytical 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
federal agencies such as the Veteran's Administration (VA) and the
various constituent agencies of the  Department of  Health and Human
Services (HHS),  (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  2378-
TCDD on  humans  and other  species,  and to  develop techniques  to
determine actual  risk given  different  levels  of  environmental
contamination.

   While investigations  into   the  extent   of  human  health  and
environmental risks  from  contamination  by  2378-TCDD  proceed,
EPA will also be evaluating different alternatives for  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,
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extraction of dioxin  from soils, and  incineration  or photolysis
for destruction of dioxins.

   Finally, the  strategy  lists  a  number of  research activities
to define  the potential  human  health  and  environmental  risks
from dioxin  isomers  other  than  2378-TCDD  and  other  "dioxin-
like" chemicals.    These  activities   include  1)  assessing  the
toxicity of  the   other  isomers,  2)  determining  their  specific
sources, 3)  evaluating  their  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,  the  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

   EPA's efforts  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  U.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 improved  its  analytical  capabilities.   In  1978,
EPA initiated  the  Rebuttable   Presumption  Against  Registration
(RPAR) process  against  pesticide  products  with  2,4,5-T.   In
1979, based  on a  study  of  miscarriage  rates  in Alsea,  Oregon
(where 2,4,5-T had  been  sprayed on  forest  land) and  extensive
laboratory data demonstrating that  2,4,5-T,  silvex,  and/or 2378-
TCDD cause cancer and adverse reproductive effects  in test animals,
EPA ordered an emergency  suspension  of 2,4,5-T  and  silvex use on
forests, rights-of-way,  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  and  lost.   In   1980,  an  EPA administrative  law
judge began consolidated  cancellation hearings  on  the  suspended
and nonsuspended   uses  of 2,4,5-T  and  silvex.   These  hearings
were postponed in  1981  to  allow Dow  and  EPA  to  concentrate  on
settlement discussions.

   Other programs have 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 EPA  is  required to control  in  industrial  effluents.   To
date, no  national discharge  regulations  have   been issued  for
2378-TCDD, primarily because it has not been detected  in effluents.
The only time  it  has  been measured  in effluents was when EPA's
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Region 5 personnel  measured  it at  the  50 parts  per  quadrillion
level in the  Dow  effluent.  (Analytical  problems may be  one  of
the reasons why  2378-TCDD was  not  otherwise detected.)   EPA  is
working with the State of  Michigan  on developing limitations for
Dow's permit.   Under the  Clean  Air Act, EPA is currently assessing
the health  impacts  of 2378-TCDD  as  a  hazardous  air  pollutant.

   As an interim step to  control the  disposal of any  wastes con-
taining 2378-TCDD (defined as wastes resulting from the production
of 2,4,5-TCP or its pesticide  derivatives, or substances produced
on equipment that was previously used  for  the production of 2,4,5-
TCP or its pesticide derivatives) ,  EPA in 1980 promulgated a rule
under the Toxic Substances Control  Act  (TSCA) which  requires any
persons intending  to  move or  otherwise  dispose  of  these  wastes
to notify EPA of its plans  60 days prior to initiating any action.
This allows EPA to  review the  plans  and ensure  that  the  wastes
are properly managed.   In 1983, EPA  proposed to  regulate  wastes
containing any  tetra-,   penta-,  and  hexachlorodibenzo-p-dioxins
under the  Resource  Conservation and  Recovery Act  (RCRA).   This
action will cover  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
including the  periodic   reporting   of progress  to  EPA's  Deputy
Administrator.  OSWER  will  directly manage the investigations
and 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
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policy or plans developed by other EPA offices that are implementing
delegated portions of the strategy.  OSWERwill also have oversight
responsibility for the  preparation  of  external  correspondence,
testimony and public  statements.

   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  officers   in  conjunction  with  the
Regions.  The actual detailed  sampling  plans for  sites in tiers
3-7 (exclusive of tier  4) will be prepared by the Regional offices
in conjunction with the States and will  be reviewed by the appro-
priate program office.   Sampling  plans  for  sites  in  tiers 1 and
2 will  be  prepared by  the  Regional  offices in conjunction  with
the States, CDC  and  NIOSH  when  appropriate.   The  individual  work
plans are to be  more specific than the  strategy and the detailed
sampling plans are, by nature,  unique to  each  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
implementation (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 plans  or  seek to  compel response.   The priority for taking
either enforcement or  response  actions at  dioxin  sites  will be
determined by evaluating the  seriousness  of the problem  at the
site relative  to  the problem  at   all   other  sites whether  they
include dioxin or  not.

   Funding for investigations  and  response  actions  for sites in
tiers 1  and 2   will  come   from  the Comprehensive  Environmental
Response, Compensation, and Liability Act (CERCLA), while funding

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for studies  related  to  tiers   3-7   will   come   from  a  special
appropriation for  what  is  referred  to  as  "The  National  Dioxin
Study".  If  contamination  is  detected  at  sites  in tiers  3-7,
the data will  be forwarded to  OSWER for further  evaluation,  in
accordance with the interim guidance.

   Implementation of  the  strategy  will  require  close  coordi-
nation with  a  number  of  other  federal agencies,  including  FDA,
CDC, NIOSH,  and  others.   OSWER is responsible  for ensuring  that
proper coordination takes place.  One of the key issues requiring
interagency coordination  is  health  and  environmental  effects
research.  OSWER,  in  conjunction with  EPA's  Office  of  Research
and Development  (ORD),  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,  EPA 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
risks 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 production.   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-
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TCP manufacturing process include wastewaters generated by contact
cooling and product  separation,  and air 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
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-
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.
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                              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 dioxin
contamination may exist in soil, water, and air, several  programs
within EPA,  at  both  the  headquarters  and regional  levels,  are
involved in this strategy; States are likewise actively 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  being contaminated with
dioxin; and (2)  to determine  the extent of environmental  contami-
nation pursuant to  an  FY  84  congressional appropriation  specifi-
cally 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 on the  number and  location  of chlorine atom
substitutions.  One  of  22  isomers   with  four  chlorine atoms,
2,3,7,8-tetrachlorodibenzo-p-dioxin (2378-TCDD),   is  of  primary
concern 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
taken to  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 potentially  contaminated with  the  most toxic  of  the
dioxin isomers,  2378-TCDD  (about  which the most  is  known,  both
on toxicology and  sources).   The other dioxin  isomers  will also
be evaluated 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
2378-TCDD effort.

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   In addition  to  the  investigation  and  response  activities
called for in the strategy, the 2378-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
affecting 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 for other  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  strategy  is that
it be  coordinated with other Federal agencies  and with  States,
as well as  within EPA.  The dioxin problem  cannot be adequately
addressed without  active  coordination of  all  these groups.  For
example,  FDA sets action  levels and consumption advisories for fish
and other consumables, CDC  issues health advisories  under  CERCLA,
and NIOSH sets limits  on exposure in the workplace.  In addition,
the Federal  Emergency Management  Agency  (FEMA)  coordinates the
relocation of  people  during  response  actions  under CERCLA, and
VA has  developed  a  large  body  of expertise from  dealing with
veterans  on the  Agent  Orange  issue.

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   States in conjunction with the  Regional  offices will continue
to have  a  major  responsibility  in investigating  and  responding
to individual  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 offices are currently
reviewing three dioxin hazard assessment documents  (ambient water
quality criteria  for  2378-TCDD;  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 have on the dioxin
strategy.  Site-specific assessments  have been  made   (the  1  ppb
action level for  soil  at Times  Beach,  Mo.), 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, EPA1s
OSWER, 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 variety  of exposure  scenarios.   This  type  of  information
is imperative for the development of action levels.
                              - 3 -

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    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 the  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

   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
include: 1) determining  the  specific  sources  of   other  dioxin
isomers, 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  causes  cancer  in
either laboratory  animals  or  humans.  The  risk  from carcinogens
is usually  expressed  in  quantitative   terms   as  a  probability
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  are not
usually expressed in probabilistic terms.

   It is  also  important to discern  between  individual  risks and
aggregate (population)   risks.   Concern  about  individual  risk
focuses on  the  effect of a  pollutant on  increasing  the  risk to

                              -  4 -

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particular individuals, without regard to the number of individuals
involved.  Concern about 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 the
chemical's potency and  the  amount of  the  chemical to  which the
animal is exposed.   Thus,  understanding or  quantifying exposure
is a necessary component in defining risk.   Comparing the quanti-
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
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-
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
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-
quently, 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 -

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                              PART 2

                      EPA'S DIOXIN STRATEGY
Study Tiers

    1.  The following tiers (or categories of sources)  are hereby
defined based on  a decreasing potential  for  2378-TCDD  contami-
nation; they will  be  addressed by this strategy  as  described in
the succeeding sections:

    Tier 1 -  Current  (if  any)  and  former  sites  of  2,4,5-TCP
              production including sites  where wastes were  dis-
              posed.  The  number  of  tier  1 production  sites is
              estimated to  be about   20;   the  total  number  of
              sites to  be  investigated   (production  sites  plus
              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  to  be  about  30,  exclusive  of  sites
              where wastes were disposed.

    Tier 3 -  Sites (current and former)  where 2,4,5-TCP and its
              derivatives (e.g.,  silvex)  were formulated  into  a
              pesticidal product.   An  example  would  be  a  site
              where 2,4-D  and  2,4,5-T 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);  wire
              reclamation facilities;  internal combustion engines;
              home heating  units  (e.g.,  wood  burning  stoves);
              industrial, fossil-fuel  fired boilers;  and inadver-
              tent combustion   sources  such  as  PCB-transformer
              fires.  The number of potential sites  in this tier
              is estimated to  be  in  the millions.

    Tier 5 -  Sites where  2378-TCDD contaminated  pesticides have
              been used or are being  used  on a commercial basis.
              These areas  include  certain  rights-of-way,  rice
              fields of  Arkansas   and  Louisiana,  pastures  and
              and western rangeland,   sugarcane fields  in Florida
              and Louisiana,  certain  aquatic  sites,  and  forests
              (e.g., Pacific  northwest).    In addition,  animals
                              - 6 -

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             animals which have  been  grazed on treated  land  and
             fish from treated waterbodies  may  contain 2378-TCDD
             residues.

   Tier 6 -   Sites  where  production  of certain  other  organic
             chemicals or pesticides  may have  resulted,  through
             improper quality control, in the  formation  of 2378-
             TCDD.  The total number  of  production  sites in this
             tier is probably less than one  hundred.

   Tier 7 -  Control  sites  selected  to evaluate  the extent  of
             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 "back-
             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 AA  for OSWER will  be assisted  by  three  coordinating
groups: (1) the Dioxin Management Task Force  (DMTF), (2) the Dioxin
Chlorinated Dioxin Work  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 be determined by the AA for OSWER.

   5.  The Dioxin  Management Task Force  will  assist  the  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
will continue to make technical recommendations about site-specific
clean-up and disposal/destruction options.

   6.  Efforts conducted in  tiers 1 and 2 will be managed directly
by OSWER and funded under CERCLA authority.
                              - 7 -

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    7.  Efforts conducted in  tiers  3 thru 7 have  been  delegated
to OW,  in  conjunction  with  appropriate  program  offices.   In
particular, OANR 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.  The program  in tiers  3  thru 7  constitutes  "The National
Dioxin Study"; it is  a  study to learn more about  the nature of  the
problem by sampling  respresentative  facilities  and  sites.   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.

    10.   Implementation  of  efforts  in  these   seven  tiers  will
proceed in  a  concurrent, parallel   fashion.   While  the  initial
efforts in tiers  3 thru  7 will  take  two years,  the comprehensive
assessment of sites in tiers 1 and 2 will extend beyond two years,
particularly at  sites where  enforcement  actions  and  clean-up
options are complex.   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

    11.   Sites  (both  manufacturing   facilities  and  waste  dis-
posal sites)  in tiers  1  and 2 will  be investigated following  the
attached guidance  (Part   3  of  this  document)   issued  by  OSWER.

    12.   The  interim  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  process  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 primary  emphasis on  tier  1  sites,  and later, on tier 1A
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.
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   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  be investigated
for 2378-TCDD  in  these  tiers,  sampling at  every  site  is  not
practicable.  One of the first steps will be to  list, using avail-
able data,  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 proper tier.

   16.  The  field  investigations to  be done  at  tiers   3  thru  6
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 — 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.

   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.
                              - 9 -

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   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,  the 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.
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   Tier 7 - Control Sites

   24.  Tiers 1  thru  6  represent  sites or areas  where contami-
nation with 2378-TCDD is either known or suspected.  A 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  be useful
in establishing the extent of outward migration of 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
specimens. 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 -

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   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,
1983.

   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   parties  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/State 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 -

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   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.

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   Detection Limits

   42.  Soil  samples  collected  during   screening  at  sites  in
tiers 1, 2,  3,  4,  and 6 will be  analytically  measured  for 2378-
TCDD 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 are 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  quadrillion
(ppq) level of detection.

   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 OWs  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, 1983.
                              - 14 -

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   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.   Samples 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  of
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.

   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).   While the
National Dioxin Study  principally focuses on 2378-TCDD, sampling
and analyses for  other chemicals may  be reasonable  in  order to
make cost-effective use of field  and laboratory  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.
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   54.  The  analytical  service  to  be  provided  by  ORD of  150
samples per month is  based on 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  reason, 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
information including the analytical  results;  analytical results
will be  sent directly  to the  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.
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   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-specific   response  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  data  collected  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.
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   66.  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.

   68.  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  se,  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 adding  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 -

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   (b)  The manufacturing  use of  tetra-,  penta-,  or hexachloro-
        benzenes 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.  Clean-
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.
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   73.  OSWER,  in  conjunction with  ORD and the  Dioxin Disposal
Advisory Group  (DDAG), will  be  responsible for pilot testing the
more promising disposal/destruction techniques.  A specific
research agenda shall be developed by December 20, 1984.

   74.  Several important questions  need  to be addressed through
pilot studies  before  these  alternatives can be  fully evaluated.
For example,  to destroy  dioxin,  the  treatment   technology  must
first break the dioxin/soil  particle  bond.   In doing so, partially
treated residues, or contaminated materials which may be released
during processing,  have  the  potential  to  spread contamination.
Therefore, ORD will consider including a sorption/desorption study
on contaminated soils as part of its research agenda to determine
dioxin release  rates.   While  these  treatment technologies  may
present the  ultimate  solution to  contaminated media,  they could
present significant health risks during processing.  Thus, during
the pilot testing  phase,  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  recommend full
field validation projects to the AA for  OSWER.  Upon approval, ORD
will implement  the  full  field validation  studies in conjunction
with the Region where testing is to occur.  Full field validation
work should commence by July 1985.

   76.  The  results of pilot  testing and  full  field validation
will be reported to OSWER.  These  results 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 2378-TCDD

   77.  EPA  realizes  that  much  remains  to be  discovered about
the effects of 2378-TCDD on  both  human health and  the environment.
The development  of specific  action  levels  is hindered  by this
fact.  This strategy recognizes that additional work must be done
in this area and the information integrated into an authoritative
view of the risks,  including development of action levels associ-
ated with exposure  to  2378-TCDD.   Delaying the implementation of
this strategy  until final action  levels  are developed, however,
is not believed to  be in the best  public interest.
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   78.  Some  of  the  studies  to be  conducted are  short-term in
nature and appropriately managed  by EPA;  other  types  of studies
are longer-term and are  beyond  the  purview  of EPA.  Thus, inter-
agency coordination in  this  area is essential.   For  purposes of
intra-agency coordination, OSWER, in conjunction with ORD and the
program offices,  will develop  a list  by  February  15,  1984  of
specific health  and  environmental  effects  research  needs  that
will assist  EPA  in implementing the  elements of  this  strategy.
This list will also be  used  to  assist  in  coordination 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  will  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  (bioaccumulation and  bio-
magnification) 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.
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   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 and 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.  This work will help establish
             the cause/effect relationship of 2378-TCDD to
             human disease.

Other Dioxins and Dioxin-like Compounds

   83.   A number of  halogenated  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 halogenated dioxins  and  furans  with
chlorine or bromine  atoms  at  positions  2,3,7,  and 8,  and with at
least one hydrogen atom on  the dioxin  or  furan structure,  are of
special concern.   These  halogenated   dioxins  and  dibenzofurans
are inadvertent by-products  of a  number  of production processes
involving halogenated phenols, and are thought also to be created
in the course of combustion  of  a variety of halogenated aromatics.
The production  and  use  of pentachlorophenol, and  of  other halo-
phenols and of  their derivates,   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  their 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.
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   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  are  also  sources  of  2378-TCDD; thus,  much
dual sampling will be avoided.

   86.  In order  to  take  advantage  of  the  sampling  effort being
conducted for  2378-TCDD,   the  Regions  will  collect  sufficient
sample volumes  to analyze  for both  2378-TCDD  and  the  "dioxin-
like" 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.

   88.  During  FY 84,  ORD will work with CDC, the U.S.  Fish and
Wildlife Service,  and other Federal  agencies to develop analytical
protocols to measure  "dioxin-like" 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 bio-
analytical 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  FY 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.

                              _ O "3 _
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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  HHS
(e.g., CDC,  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 EPA1s 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.

   94.  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  response  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  EPA1s  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.
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   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.
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                              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);

   2)  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  —  2,3,7,8-tetrachlorodibenzo-p-
dioxin (2378-TCDD).  The  other dioxin 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 TCDD 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 2378-
TCDD in  the  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.
                              - 26 -

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   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 -

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       Collect  information  for
       begin identification  of
       sites.
        known  tier
       tier  1A and
1  and   2  sites  to
 2A facilities  and
       Depending  on  the results,  arrange  site  visits,  employee
       interviews, and  other  evidence  collection  necessary  in
       the field.
   Field Investigation

   1.  Sampling at  tier 1 sites
       mat ion collection phase.
        should begin  during the  infor-
   2.  No  new  sampling
       until the  results
       are analyzed,  and
       proceed. The same
should  be  initiated  at  tier  2   sites
of  the  information  collection process
 the   Agency  determines  how  it  will
is true  for transportation,  treatment,
    handlers or  sites  associated  with
       storage and  disposal
       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  on 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.
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   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  (OPTSE)  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.

   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  S104/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.
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   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 that 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.
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   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 record inspections
and/or collect  environmental  media  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  -

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       samples in  addition  to  any  of  the  identifiers  used.
       (Coordination should be through the Regional Environmental
       Services Division (BSD) Directors).

   4)  If  the initial  sampling  results  indicate 2378-TCDD  is
       present, and  response  action  is  to  be  pursued  through
       either enforcement or Fund-financed activities, the proce-
       dures set   forth  in  the 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 work-
plan 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
point for  communications with the  local citizens  and  the press
at a site.
                              - 32 -

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   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,   after  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/
       feasibility 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  -

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   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 option  2  is  chosen,  the proce-
dures outlined  for  "removals"   in  the  Response  Section  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  be  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 pursue,
after consultation with  OWPE and OEC-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

   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  recovery  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
                              -  34 -

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involve joint  federal  EPA and  State  efforts.  Depending  on the
success of  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
needed.  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  (NPL), 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 BSD 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 -

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        implements the determination.  EPA also has the responsi-
        bility for making the  determination  concerning permanent
        relocation, and FEMA implements 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
goal.  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 EPA guidance
issued on March 8, 1983.
                              - 36 -

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                                                               TIER 1
OWE List of 2,4,5-TCP
Manufacturers ard 2,4,5-TCP
Pesticide Derivative
Manufacturers
CO
•--I
                                                                                       FIGURE I
FIFRA Inspection
       or
TSCA Inspection/Sampling
       or
Superfund Screening
Review (
ard fed«
HQ, Reg
e
104/3007
OWPE List
Df local, .state
;ral files by
on, and State
Letters to
: of Facilities
	 Manufacturers of -~*f^w^
2,4,5-TCP ^"^^h.
TIER la
_» TTSD facilities of
TIER 1 *
{TIER 2
Sites where 2,4,5-TCP
was used as a precursor >^*2*
to produce another *£f*
chemical product C^*^
<8w
Superfund Screening
Consult with OSWER
prior to taking
further action
FIFRA Inspection
or
TSCA Inspection/San!
or
Superfund Screening
                                                                                                                       2,3,7,8-TCDD
                                                                                                                       present
                                                       Response  Action (see  Fig. 2)
                                                           and
                                                       Additional  information
                                                       gathering for enforcement
                                                       purposes, e.g., files search,
                                                       interviews,  responsible party
                                                       search
                             ,No 2,3,7,8-TCDD
                              Present
                                                                                                                                                No Response Action]
                                                                                        '"Supsrfund Screening
                                                               TIER  2l

                                                           TT3) facilities of
                                                           TIER  2
Consult with OSWER
prior to taking
further action

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                                                                      FIGURE 2
                                       S3013 A.O. for RI
                           ->  EPA does FS
GO
co
     NOTICE LETTER
     FOR RI/FS/RD/RA
                                       S3013/106 A.O. for
                                       RI/FS/RD/RA

                                             or

                                       S106 and/or §7003
                                       Consent Decree for
                                       RI/FS/RD/RA
                                                               c°"*''y
 §3013 Unilateral A.O.-
 for RI

       or

-Fund-Financed RI/FS
 and/or Removal
                                       Enforcement-Financed
                                      -Endangerment/Alternatives
                                       Assessment
                                                                   > EPA does FS
-»• f!06 and/or S7003 A.O.
   or Consent  Decree
                                                                                   urooopmVv*
                                                                         negotiate RD/RA
                                                                         00-120 days
                                                                                              >»§106 and/or §7003  Unilateral
                                                                                              •"A.O. for RD/RA
                  or

       '§106/7003  Civil Action

                  or

      -» Fund-financed  RD/RA

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                           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
dioxin1s 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 -

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   0 The need to process  a  wide  range of contaminated materials,
     e.g., rocks,  clay,  roots,  and  other  materials  on-site.

   0 The requirement that the  remedial  alternative  be capable of
     processing all contaminated  material.   Combination of reme-
     dial alternatives  for  various  types  and  concentrations of
     contaminated material were not considered.

   0 The use  of Level  C  or higher personnel  protection  for  all
     soil handling and treatment activities.

   0 The potential listing of 2378-TCDD as a RCRA waste, which will
     significantly impact  storage,  transportation,  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  in  a  fully  permitted  secure
     landfill.

   The following  six   remedial alternatives   were  selected  for
a detailed evaluation  at  the Minker/Stout  site.  Alternatives D,
E, F 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-contaminated 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 the  soil  in  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 water  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 -

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   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
vault, 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 solvent  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-
                              - 41 -

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going degradation and  incineration.   The  incinerator particulate
and the  soil  residue would  be sent  to  a secure  landfill site,
unless extensive  testing  allowed  the  residue  to   be  delisted.

   Alternative F — Storage While Awaiting Development of
   Emerging Technology

   This alternative would  allow for the  development  of  emerging
technologies other than incineration and solvent extraction.  The
contaminated soil would be  removed  and stored until 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  guickly 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 and,  therefore,  soil particle movement  is necessary to
spread the contamination.

   Containment technologies  are based  on  the dioxin-soil 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-term
basis, then  excavation and  temporary  storage will  be  required.


                               - 42  -

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   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 are 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 of any future pilot testing program.
                              - 43 -

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