United States
Environmental Protection
Agency
Office of Water
Regulations and Standards
Washington, DC 20460
Water
                June, 1985
Environmental  Profiles
and Hazard Indices
for Constituents
of Municipal Sludge:
Chlorinated Dibenzofurans

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                                 PREFACE
     This document is one of  a  series  of preliminary assessments dealing
with  chemicals  of potential  concern  in municipal  sewage sludge.   The
purpose of these  documents  is to:   (a)  summarize  the  available data for
the  constituents  of  potential  concern,  (b) identify  the key environ-
mental  pathways  for  each  constituent  related  to  a reuse and disposal
option  (based on  hazard indices),  and  (c) evaluate the conditions under
which such a pollutant  may  pose a  hazard.   Each document provides a sci-
entific basis  for making an  initial  determination of whether  a pollu-
tant, at levels currently observed in  sludges, poses  a likely hazard to
human health  or  the  environment  when  sludge  is  disposed of  by  any of
several methods.   These methods include landspreading on  food chain or
nonfood chain  crops, distribution  and marketing  programs, landfilling,
incineration and ocean disposal.

     These documents  are  intended  to serve as a rapid screening tool to
narrow  an initial list  of pollutants  to those  of  concern.  If a signifi-
cant  hazard  is  indicated by  this  preliminary analysis,  a more detailed
assessment will   be  undertaken to  better  quantify the  risk  from  this
chemical and  to  derive criteria if warranted.   If a  hazard  is shown to
be unlikely, no  further assessment will be conducted  at  this time;  how-
ever,  a reassessment  will  be  conducted  after  initial  regulations  are
finalized.  In no case, however,  will  criteria be derived solely on the
basis of information presented in this document.

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                            TABLE OP CONTENTS


                                                                     Page

PREFACE 	   i

1.  INTRODUCTION	  1-1

2.  PRELIMINARY CONCLUSIONS FOR TETRACHLORODIBENZOFURANS IN
      MUNICIPAL SEWAGE SLUDGE 	  2-1

    Landspreading and Distribution-and-Marketing 	  2-1

    Landfilling 	  2-1

    Incineration 	  2-1

    Ocean Disposal 	  2-1

3.  PRELIMINARY HAZARD INDICES FOR TETRACHLORODIBENZOFURANS IN
      MUNICIPAL SEWAGE SLUDGE 	  3-1

    Landspreading and Distribution-and-Marketing 	  3-1

    Landfilling 	  3-1

    Incineration 	  3-1

         Index of air concentration increment resulting
           from incinerator emissions (Index 1) 	  3-1
         Index of human cancer risk resulting from
           inhalation of incinerator emissions (Index 2) 	  3-3

    Ocean Disposal 	  3-5

         Index of seawater concentration resulting from
           initial mixing of sludge (Index 1) 	  3-5
         Index of seawater concentration representing a
           24-hour dumping cycle (Index 2) 	  3-8
         Index of toxicity to aquatic life (Index 3) 	  3-9
         Index of human cancer risk resulting from seafood
           consumption (Index 4) 	  3-10

4.  PRELIMINARY DATA PROFILE FOR TETRACHLORODIBENZOFURANS IN
      MUNICIPAL SEWAGE SLUDGE 	  4-1

    Occurrence 	  4-1

         Sludge 	  4-1
         Soil - Unpolluted 	  4-1
         Water - Unpolluted 	  4-1
         Air 	  4-1
         Food 	  4-2
                                   11

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                            TABLE OP CONTENTS
                               (Continued)

                                                                      Page

    Human Effects 	   4-2

         Ingestion 	   4-2
         Inhalation 	   4-3

    Plant Effects 	   4-3

    Domestic Animal and Wildlife Effects 	   4-3

         Toxicity	   4-3
         Uptake 	   4-3

    Aquatic Life Effects 	   4-4

         Toxicity	   4-4
         Uptake 	   4-4

    Soil Biota Effects 	   4-4

         Toxicity	   4-4
         Uptake 	   4-4

    Physicochemical Data for Estimating Fate and Transport  	   4-4

5.  REFERENCES	   5-1

APPENDIX.  PRELIMINARY HAZARD INDEX CALCULATIONS FOR
    TETRACHLORODIBENZOFURANS IN MUNICIPAL SEWAGE SLUDGE 	   A-l
                                   111

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                                SECTION 1

                               INTRODUCTION
     This  preliminary  data profile  is  one  of  a  series  of  profiles
dealing  with chemical  pollutants  potentially of  concern  in municipal
sewage sludges.  Tetrachlorodibenzofurans  (TCDFs) were initially  identi-
fied as  being  of potential concern when sludge  is  incinerated  or ocean
disposed.* This profile is  a compilation of information that may  be use-
ful in determining  whether TCDFs pose  an  actual hazard  to human health
or the environment when sludge is disposed of by these methods.
     The  focus   of  this  document  is  the  calculation of  "preliminary
hazard indices"  for  selected  potential exposure  pathways, as  shown in
Section  3.   Each  index illustrates  the hazard  that could  result  from
movement  of  a  pollutant  by  a  given pathway  to cause  a  given  effect
(e.g., sludge * air - human toxicity; sludge * seawater *  marine  organ-
isms * human toxicity).   The  values and  assumptions employed  in these
calculations tend  to  represent  a reasonable  "worst case";  analysis  of
error  or uncertainty  has  been  conducted  to  a  limited  degree.   The
resulting value  in  most cases  is indexed  to unity;  i.e.,  values  >1 may
indicate  a   potential  hazard,  depending  upon  the   assumptions   of  the
calculation.
     The data used for  index calculation have  been  selected or estimated
based  on  information  presented  in   the   "preliminary  data  profile",
Section 4.   Information in  the profile  is  based on  a compilation  of the
recent literature.   An attempt  has  been  made to  fill out  the  profile
outline to the greatest extent possible.   However,  since  this is  a  pre-
liminary analysis,  the literature has  not been exhaustively perused.
     The  "preliminary  conclusions"  drawn  from each  index in Section  3
are summarized  in  Section  2.    The  preliminary  hazard  indices  will  be
used as a screening tool  to determine which pollutants  and  pathways may
pose a hazard.   Where a potential hazard  is  indicated  by interpretation
of these  indices,  further  analysis  wilL include  a more  detailed  exami-
nation of  potential risks  as  well as  an  examination of  site-specific
factors.    These more  rigorous  evaluations may  change the  preliminary
conclusions   presented  in  Section 2,  which are  based  on a  reasonable
"worst case" analysis.
     The  preliminary  hazard   indices   for  selected   exposure   routes
pertinent to incineration  and  ocean  disposal  practices are  included  in
this profile.   The  calculation formulae for these  indices are shown  in
the Appendix. The  indices  are  rounded to two significant figures.
  Listings  were  determined  by  a  series  of  expert  workshops  convened
  during  March-May,   1984  by  the  Office  of  Water  Regulations   and
  Standards  (OWRS) to  discuss  landspreading,  landfilling,  incineration,
  and ocean disposal,  respectively,  of municipal  sewage  sludge.
                                   1-1

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                                SECTION 2

           PRELIMINARY CONCLUSIONS  FOR TETRACHLORODIBENZOFURANS
                       IN MUNICIPAL SEWAGE  SLUDGE
     The  following  preliminary  conclusions  have been  derived  from the
calculation of  "preliminary hazard  indices",  which  represent  conserva-
tive or  "worst  case" analyses  of  hazard.   The  indices and  their basis
and  interpretation  are  explained  in  Section  3.    Their  calculation
formulae are shown in the Appendix.

  I. LANDSPREADING AND DISTRIBUTION-AND-MARKETING

     Based on  the recommendations  of  the experts  at the  OWRS  meetings
     (April-May,  1984),  an  assessment of  this reuse/disposal option  is
     not being  conducted  at  this time.   The U.S. EPA reserves  the right
     to conduct such an assessment for this option in the future.

 II. LANDPILLING

     Based on  the recommendations  of  the experts  at the  OWRS  meetings
     (April-May,  1984),  an  assessment of  this reuse/disposal option  is
     not being  conducted  at  this time.   The U.S. EPA reserves  the right
     to conduct such an assessment for this option in the future.

III. INCINERATION

     Conclusions  were  not   drawn   because   index  values  could  not  be
     calculated due to lack of data.

 IV. OCEAN DISPOSAL

     Conclusions  were  not   drawn   because   index  values  could  not  be
     calculated due to lack of data.
                                   2-1

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                                SECTION 3

         PRELIMINARY HAZARD INDICES FOR TETRACHLORODIBENZOFURANS
                       IN MUNICIPAL SEWAGE SLUDGE
  I. LANDSPREADING AND DISTRIBUTION-AMD-MARKETING

     Based on  Che recommendations  of  the experts  at  the OWRS  meetings
     (April-May,   1984),  an  assessment of  this  reuse/disposal option  is
     not being conducted at  this  time.   The U.S. EPA  reserves  the right
     to conduct such an assessment for this option in the future.

 II. LANDFILLING

     Based on  the recommendations  of  the experts  at  the OURS  meetings
     (April-May,   1984),  an  assessment of  this  reuse/disposal option  is
     not being conducted at  this  time.   The U.S. EPA  reserves  the right
     to conduct such an assessment for this option in the future.

III. INCINERATION

     A.   Index of Air Concentration Increment Resulting from
          Incinerator Emissions (Index 1)

          1.    Explanation  -  Shows  the  degree  of  elevation   of  the
               pollutant concentration in the  air  due to the  incinera-
               tion of  sludge.   An input sludge with  thermal  properties
               defined  by the  energy parameter  (EP) was analyzed using
               the  BURN model   (Camp  Dresser  and  McKee,  Inc.  (CDM),
               1984a).  This model  uses  the thermodynamic and mass bal-
               ance relationships appropriate for multiple hearth incin-
               erators to relate the input  sludge characteristics to the
               stack gas parameters.   Dilution  and dispersion  of these
               stack  gas releases  were  described  by  the  U.S.  EPA's
               Industrial Source  Complex  Long-Term  (ISCLT)  dispersion
               model from which normalized annual  ground level  concen-
               trations were predicted (U.S. EPA,  1979).  The  predicted
               pollutant concentration can  then  be  compared to  a ground
               level concentration used  to assess risk.

          2.    Assumptions/Limitations -  The fluidized  bed  incinerator
               was  not  chosen  due to  a  paucity  of  available  data.
               Gradual plume rise,  stack tip downwash, and building wake
               effects   are appropriate  for describing plume  behavior.
               Maximum  hourly   impact values   can   be  translated  into
               annual average values.

          3.    Data Used and Rationale

               a.   Coefficient to correct for  mass and  time units (C)  =
                    2.78 x  10~7 hr/sec x  g/mg
                                   3-1

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b.   Sludge feed rate (DS)

       i. Typical = 2660 kg/hr (dry solids input)

          A  feed  rate  of  2660  kg/hr  DW represents  an
          average  dewatered  sludge  feed rate  into  the
          furnace.  This  feed rate would  serve  a commun-
          ity of approximately 400,000 people.   This rate
          was incorporated  into  the  U.S.  EPA-ISCLT model
          based on the following input data:

               EP - 360 Ib H20/mm BTU
               Combustion zone temperature - 1400F
               Solids content - 28%
               Stack height - 20 m
               Exit gas velocity - 20 m/s
               Exit gas temperature - 356.9K (183F)
               Stack diameter - 0.60 m

      ii. Worst = 10,000 kg/hr (dry solids input)

          A  feed rate  of  10,000  kg/hr  DW  represents  a
          higher feed  rate and would serve  a major U.S.
          city.   This rate  was  incorporated  into the U.S.
          EPA-ISCLT   model based  on   the  following  input
          data:

               EP = 392 Ib H20/mm BTU
               Combustion zone temperature -  1400F
               Solids content - 26.6%
               Stack height - 10 m
               Exit gas velocity - 10 m/s
               Exit gas temperature - 313.8"K (105F)
               Stack diameter - 0.80 m

c.   Sludge  concentration of  pollutant  (SC)  -  Data  not
     immediately available.

     Concentrations of  TCDFs  in  municipal sewage  sludge
     were not analyzed  in  the U.S.  EPA  (1982a)  study  of
     50  publicly-owned  treatment  works  (POTWs)  and  were
     not  available  for  sludge  -data for  POTWs  located
     throughout  the United States  (COM, 1984b).

d.   Fraction of pollutant emitted through stack (PM)

     Typical    0.05 (unitless)
     Worst      0.20 (unitless)

     These  values  were  chosen as  best  approximations  of
     the  fraction  of   pollutant  emitted  through  stacks
     (Farrell, 1984).   No data was available to validate
     these values; however, U.S. EPA  is  currently testing
     incinerators for organic emissions.
                    3-2

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          e.   Dispersion parameter for estimating maximum annual
               ground level concentration (DP)

               Typical    3.4
               Worst     16.0

               The  dispersion  parameter  is  derived  from  the  U.S.
               EPA-ISCLT short-stack model.

          f.   Background concentration  of  pollutant  in urban air
               (BA) = 0.0000001 Ug/m3

               Assuming that polychlorinated biphenyl  (PCB) is  con-
               taminated with /*1.25  ppm  TCDFs,  and  that  ambient air
               concentration of  PCB  is  100 ng/m3,  an  ambient air
               concentration for  TCDFs  of 0.0000001  Ug/m3  can  be
               estimated  (U.S.   EPA,   1983).     (See   Section  4,
               p. 4-1.)

     4.   Index  1  Values  - Values were  not  calculated  due  to  lack
          of data.

     5.   Value  Interpretation  -  Value  equals  factor  by  which
          expected air  concentration exceeds background  levels due
          to incinerator emissions.

     6.   Preliminary Conclusion - Conclusion was not  drawn because
          index values could not be calculated.

B.   Index  of  Human  Cancer  Risk  Resulting  from  Inhalation  of
     Incinerator Emissions (Index 2)

     1.   Explanation - Shows  the  increase  in human  intake  expected
          to result from  the  incineration of sludge.  Ground level
          concentrations  for  carcinogens  typically  were  developed
          based upon assessments published by the U.S. EPA  Carcino-
          gen Assessment Group  (CAG).  These ambient concentrations
          reflect  a dose  level  which,   for a  lifetime  exposure,
          increases the risk of cancer by 10~6.

     2.   Assumptions/Limitations  -   The  exposed  population  is
          assumed  to  reside  within  the '  impacted   area   for  24
          hours/day.   A  respiratory volume of  20 m3/day is assumed
          over a 70-year lifetime.

     3.   Data Used and Rationale

          a.   Index of air concentration increment  resulting from
               incinerator emissions  (Index 1)  - Values were  not
               calculated due to lack of  data.

               See Section 3,  p. 3-3.
                              3-3

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     b.   Background  concentration  of  pollutant  in  urban air
          (BA) = 0.0000001 Ug/m3

          See Section 3, p. 3-3.

     c.   Cancer potency - Data not immediately available.

     d.   Exposure  criterion   (EC)   -   Data  not  immediately
          available.

          A  lifetime  exposure  level  which  would result  in  a
          10~6 cancer  risk was selected  as ground  level con-
          centration  against  which  incinerator  emissions  are
          compared.   The risk  estimates  developed by  CAG are
          defined as the lifetime incremental  cancer  risk in a
          hypothetical    population    exposed    continuously
          throughout  their  lifetime  to  the stated  concentra-
          tion  of  the  carcinogenic   agent.     The  exposure
          criterion is calculated  using the following formula:

               Ec _  10"6 x 103 Ug/mg x  70 kg
                    Cancer potency x 20 m-Vday

4.   Index 2  Values - Values were  not  calculated due  to lack
     of data.

5.   Value Interpretation  - Value  >  1  indicates a  potential
     increase  in  cancer  risk  of >  10"^  (1   per  1,000,000).
     Comparison with the null  index  value at  0 kg/hr  DW indi-
     cates the  degree  to  which  any  hazard is  due  to  sludge
     incineration,   as   opposed   to   background  urban   air
     concentration.

6.   Preliminary Conclusion - Conclusion  was not  drawn because
     index values could not be calculated.
                         3-4

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IV.  OCEAN DISPOSAL

     For  the  purpose  of  evaluating  pollutant   effects  upon  and/or
     subsequent uptake  by marine life  as  a  result of  sludge  disposal,
     two types of  mixing  were modeled.  The initial mixing  or dilution
     shortly after dumping of a single load  of  sludge  represents a high,
     pulse  concentration  to  which  organisms may  be  exposed  for  short
     time periods  but which  could  be repeated  frequently;  i.e.,  every
     time a  recently dumped  plume  is encountered.   A  subsequent  addi-
     tional  degree  of mixing  can be  expressed by  a  further  dilution.
     This is  defined  as  the  average dilution  occurring  when a  day's
     worth of  sludge is dispersed  by 24 hours  of current movement  and
     represents  the  time-weighted  average  exposure  concentration  for
     organisms in the disposal area.  This dilution accounts  for 8 to 12
     hours of the  high  pulse  concentration encountered  by the  organisms
     during daylight disposal operations and 12 to 16 hours  of recovery
     (ambient  water  concentration)  during  the   night  when   disposal
     operations are suspended.

     A.   Index of  Seawater Concentration  Resulting from  Initial  Mixing
          of Sludge (Index 1)

          1.   Explanation - Calculates increased  concentrations  in  ug/L
               of  pollutant  in seawater around an  ocean  disposal  site
               assuming initial  mixing.

          2.   Assumptions/Limitations  -   Assumes   that   the  background
               seawater concentration of  pollutant is  unknown   or  zero.
               The  index  also assumes  that  disposal  is  by  tanker  and
               that  the  daily  amount of  sludge  disposed is  uniformly
               distributed  along  a  path   transversing  the   site   and
               perpendicular  to  the  current   vector.     The  initial
               dilution volume   is  assumed  to  be  determined   by  path
               length,  depth   to  the  pycnocline   (a   layer  separating
               surface and  deeper water masses),  and  an  initial  plume
               width defined as the width  of the plume  four  hours  after
               dumping.   The seasonal disappearance of the pycnocline is
               not considered.

          3.   Data Used and Rationale

               a.   Disposal conditions

                               Sludge          Sludge Mass        Length
                               Disposal        Dumped by  a       of Tanker
                               Rate  (SS)     Single  Tanker (ST)    Path (L)

                    Typical     825 mt  DW/day     1600 mt WW         8000 m
                    Worst      1650 mt  DW/day     3400 mt WW         4000 m


                    The  typical  value for the sludge disposal rate  assumes
                    that  7.5  x  10^ mt  WW/year  are  available  for  dumping
                    from a metropolitan  coastal  area.    The conversion  to


                                  3-5

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     dry  weight assumes  4 percent  solids  by  weight.    The
     worst-case  value  is  an  arbitrary  doubling   of   the
     typical value to allow for potential future  increase.

     The  assumed  disposal practice  to  be  followed at the
     model  site representative of  the typical  case  is  a
     modification of  that proposed  for sludge disposal at
     the  formally designated  12-mile site  in the New York
     Bight  Apex  (City of New York,  1983).   Sludge barges
     with  capacities  of  3400 mt  WW would  be  required to
     discharge  a  load in no less than 53  minutes travel-
     ing  at  a  minimum speed of 5 nautical  miles (9260 m)
     per  hour.  Under  these conditions,  the  barge  would
     enter  the  site,  discharge  the  sludge  over 8180 m and
     exit  the   site.    Sludge  barges  with  capacities  of
     1600 mt WW would be required to  discharge  a load in
     no less than 32  minutes  traveling at  a minimum speed
     of  8  nautical   miles  (14,816  m)  per  hour.   Under
     these  conditions,  the  barge would  enter  the  site,
     discharge  the  sludge over 7902 m  and  exit the site.
     The mean path length for  the large and small tankers
     is 8041 m  or approximately  8000  m.   Path  length  is
     assumed  to  lie  perpendicular  to  the  direction  of
     prevailing  current  flow.  For  the typical  disposal
     rate  (SS)  of 825 mt DW/day, it is  assumed that  this
     would  be  accomplished by  a  mixture of  four 3400 mt
     WW and four  1600 mt  WW capacity barges.   The overall
     daily  disposal  operation  would  last  from  8 to  12
     hours.   For  the  worst-case disposal  rate  (SS)  of
     1650 mt DW/day,  eight  3400 mt  WW and eight  1600  mt
     WW capacity  barges would  be  utilized.    The overall
     daily  disposal  operation  would  last  from  8 to  12
     hours.    For both  disposal  rate  scenarios,  there
     would be a 12 to 16  hour period at  night  in which no
     sludge would  be dumped.   It  is  assumed  that  under
     the   above   described  disposal   operation,   sludge
     dumping would occur every day of the year.

     The  assumed  disposal  practice at  the  model  site
     representative  of  the worst  case is  as  stated  for
     the typical site,  except that barges would  dump  half
     their  load  along  a track,' then  turn  around  and
     dispose of the balance along the  same  track in  order
     to prevent a barge from dumping outside  of  the  site.
     This   practice  would  effectively  halve   the   path
     length compared  to  the typical  site.

b.   Sludge concentration of pollutant  (SC)  - Data  not
     immediately available.

     See Section 3,  p. 3-2.
                     3-6

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     c.    Disposal  sice characteristics

                                          Average
                                          current
                       Depth to           velocity
                   pycnocline (D)       at site  (V)

          Typical       20 m             9500  in/day
          Worst          5 m             4320  m/day

          Typical  site  values  are representative  of a  large,
          deep-water  site  with  an  area  of  about  1500  km*
          located  beyond the continental shelf in  the New York
          Bight.   The  pycnocline value of  20 m chosen  is  the
          average  of  the  10 to  30  m  pycnocline  depth  range
          occurring  in  the  summer  and  fall; the winter  and
          spring  disappearance of the pycnocline  is  not  consi-
          dered  and so  represents a  conservative approach  in
          evaluating annual  or  long-term  impact.  The  current
          velocity  of  11 cm/sec  (9500  m/day)  chosen is  based
          on the average current velocity in this  area  (CDM,
          198Ac).

          Worst-case values are representative of  a  near-shore
          New York  Bight site with  an area  of  about 20  km2.
          The pycnocline  value of 5  m chosen  is the  minimum
          value  of  the  5 to  23 m depth  range  of the  surface
          mixed  layer  and  is  therefore  a  worst-case  value.
          Current  velocities  in  this  area  vary  from  0  to
          30 cm/sec.   A value  of   5  cm/sec (4320  m/day)  is
          arbitrarily  chosen  to represent a worst-case  value
          (CDM,  1984d).

4.   Factors Considered in Initial Nixing

     When a load of sludge  is  dumped from a moving  tanker,  an
     immediate mixing  occurs  in the  turbulent  wake  of  the
     vessel, followed by  more  gradual  spreading of  the  plume.
     The  entire  plume,  which  initially  constitutes a  narrow
     band the length of  the  tanker path, moves more-or-less  as
     a  unit  with the  prevailing  surface current  and,  under
     calm conditions,  is  not further  dispersed by the  current
     itself.  However, the  current acts to separate  successive
     tanker loads,  moving each out of  the  immediate disposal
     path before  the next load is dumped.

     Immediate  mixing    volume   after   barge   disposal   is
     approximately   equal  to the  length of  the  dumping  track
     with a cross-sectional area about  four  times  that  defined
     by  the  draft  and  width  of   the  discharging   vessel
     (Csanady, 1981, as  cited in NOAA,  1983).   The  resulting
     plume is initially 10 m deep by  40  m wide  (O'Connor  and
     Park,  1982,    as   cited  in  NOAA,  1983).     Subsequent
     spreading of plume  band width occurs at an  average  rate
                         3-7

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          of approximately 1 cm/sec (Csanady et  al.,  1979,  as cited
          in NOAA, 1983).  Vertical mixing is limited  by  the depth
          of the pycnocline or ocean floor, whichever is shallower.
          Four hours after disposal, therefore,  average plume width
          (W) may be computed as  follows:

          W = 40 m + 1 cm/sec x 4 hours x  3600  sec/hour x  0.01 m/cm
          = 184 m = approximately 200 m

          Thus  the volume  of  initial mixing   is  defined  by  the
          tanker path,  a 200 m  width,  and a  depth  appropriate  to
          the site.  For  the typical  (deep water) site, this depth
          is chosen as the pycnocline value of  20 m.   For  the worst
          (shallow water)  site,  a  value   of  10 m was  chosen.   At
          times the pycnocline may  be  as  shallow as  5  m,  but since
          the barge  wake causes  initial  mixing  to  at  least  10 m,
          the greater value was  used.
         
     5.    Index 1  Values  ()ig/L) - Values  cannot be  calculated  due
          to lack  of data  on detection limits for TCDFs in  sludge.
          If this  information were available, all null  values would
          be 0, and all other values would be expressed in  the form
          of "less than".

     6.    Value Interpretation - Value equals the expected  increase
          in TCDF  concentration  in  seawater  around a  disposal site
          as a result of sludge  disposal after initial mixing.

     7.    Preliminary Conclusion - Conclusion was not  drawn  because
          index values  could  not  be  calculated.

B.   Index of Seawater Concentration Representing a  24-Hour  Dumping
     Cycle (Index 2)

     1.    Explanation -  Calculates  increased  effective concentra-
          tions in Ug/L of  pollutant  in  seawater  around  an  ocean
          disposal  site  utilizing  a   time weighted  average  (TWA)
          concentration.   The TWA concentration  is that which would
          be experienced by  an  organism remaining stationary (with
          respect to the ocean floor) or moving  randomly within  the
          disposal vicinity.   The dilution volume is  determined  by
          the tanker  path  length and  depth to  pycnocline or,  for
          the shallow water  site,  the  10 m effective  mixing  depth,
          as before, but  the effective width  is now determined  by
          current movement perpendicular to the  tanker  path  over  24
          hours.

     2.    Assumptions/Limitations -  Incorporates all  of the  assump-
          tions used  to  calculate  Index  1.    In addition,   it  is
          assumed  that   organisms  would  experience   high-pulsed
          sludge concentrations  for 8  to  12  hours per  day and then
          experience recovery (no exposure to  sludge)  for  12  to  16
          hours per  day.   This  situation  can be  expressed  by  the
          use of a TWA concentration of sludge constituent.
                              3-8

-------
     3.   Data Used and Rationale

          See Section 3, pp. 3-5 to 3-7.

     4.   Factors  Considered  in  Determining Subsequent  Additional
          Degree of Mixing (Determination of TWA Concentrations)

          See Section 3, p. 3-8.

     5.   Index 2  Values  (yg/L) -  Values  cannot be  calculated due
          to lack  of  data  on  detection limits for  TCDFs  in sludge.
          If this  information were  available, all  null values would
          be 0, and all other values would  be expressed in the form
          of "less than".

     6.   Value   Interpretation  -  Value   equals   the   effective
          increase in TCDF concentration expressed  as a TWA concen-
          tration in seawater around a  disposal  site  experienced by
          an organism over a 24-hour period.

     7.   Preliminary Conclusion -  Conclusion was  not drawn because
          index values could not be calculated.

C.   Index of Toxicity to Aquatic Life (Index 3)

     1.   Explanation - Compares the effective  increased  concentra-
          tion of  pollutant in seawater around  the   disposal  site
          resulting  from  the  initial   mixing  of  sludge   (Index  1)
          with the marine ambient  water quality  criterion of  the
          pollutant,  or with  another  value judged   protective  of
          marine  aquatic   life.    For  TCDFs,  this  value  is  the
          criterion that will protect marine aquatic  organisms from
          both acute and chronic toxic  effects.

          Wherever a  short-term,  "pulse" exposure  may occur  as  it
          would from  initial mixing,  it is usually evaluated  using
          the  "maximum"  criteria   values  of  EPA's  ambient  water
          quality  criteria  methodology.     However,  under   this
          scenario,  because  the  pulse  is   repeated  several  times
          daily on  a long-term basis,  potentially resulting  in  an
          accumulation of  injury,  it  seems  more appropriate  to  use
          values   designed   to   be  protective   against   chronic
          toxicity.     Therefore,  to   evaluate  the  potential  for
          adverse  effects  on  marine  life  resulting  from  initial
          mixing  concentrations,   as  quantified  by  Index  1,  the
          chronically derived  criteria  values are  used.

     2.   Assumptions/Limitations - In  addition  to the  assumptions
          stated  for Indices  1 and  2,  assumes   that all  of  the
          released pollutant  is available  in  the  water  column  to
          move through predicted pathways (i.e., sludge to seawater
          to aquatic organism to man).   The possibility  of  effects
          arising  from  accumulation in  the  sediments is  neglected
          since the U.S.  EPA presently  lacks a satisfactory method
          for deriving sediment  criteria.

                              3-9

-------
     3.   Data Used and Rationale

          a.   Concentration  of  pollutant  in  seawater  around  a
               disposal  site  (Index  1)  -  Values  could  noc  be
               calculated due .to lack of data.

               See Section 3, p. 3-8.

          b.   Ambient water quality criterion (AWQC) = 1,800 Ug/L

               The criterion is based  on  acute  toxicity results for
               one  species  of  saltwater  fish.    Data  necessary to
               derive chronic  toxicity criterion are  not  presently
               available (U.S. EPA, 1982b).

     4.   Index 3  Values -  Values could not be calculated  due to
          lack of Index 1 values.

     5.   Value Interpretation  -  Value  would equal  the  factor by
          which  the  expected   seawater   concentration  increase  in
          TCDFs  exceeds  the  marine  water  quality criterion.    A
          value >1  would indicate that  a toxic hazard  might exist
          for aquatic life.

     6.   Preliminary Conclusion - Conclusion was not  drawn because
          index values could not be calculated.

D.   Index of  Human Cancer  Risk Resulting  from  Seafood Consumption
     (Index 4)

     1.   Explanation - Estimates  the expected  increase   in  human
          pollutant  intake  associated   with   the   consumption  of
          seafood, a fraction of which originates from the disposal
          site vicinity,  and  compares the  total  expected  pollutant
          intake with the cancer  risk-specific  intake  (RSI)  of the
          pollutant.

     2.   Assumptions/Limitations  -  In addition to  the assumptions
          listed  for Indices  1 and  2,  assumes that  the  seafood
          tissue concentration  increase   can  be  estimated  from the
          increased  water  concentration   (Index  2)  by  a  bioconcen-
          tration  factor.    It also  assumes  that, over  the  long
          term, the  seafood catch from  the disposal  site vicinity
          will  be  diluted  to  some  extent  by   the  catch  from
          uncontaminated areas.

     3.   Data Used and Rationale

          a.   Concentration  of  pollutant  in   seawater  around  a
               disposal  site  (Index  2)  -  Values  could  not  be
               calculated due to lack of  data.

               See Section 3, p. 3-9.
                             3-10

-------
     Since  biconcentration  is  a  dynamic  and  reversible
     process,  it  is  expected   that   uptake  of  sludge
     pollutants by marine  organisms at  the disposal  site
     will  reflect  TWA  concentrations,  as  quantified  by
     Index 2, rather than pulse concentrations.

b.   Dietary consumption of seafood (QP)

     Typical     14.3 g WW/day
     Worst       41.7 g WW/day

     Typical and  worst-case values are the  mean  and the
     95th   percentile,   respectively,    for   all   seafood
     consumption in  the  United States  (Stanford  Research
     Institute (SRI) International, 1980).

c.   Fraction  of  consumed  seafood originating  from the
     disposal site (PS)

     For  a -typical  harvesting scenario,  it was  assumed
     that  the  total  catch  over a wide  region is  mixed by
     harvesting, marketing  and  consumption practices, and
     that  exposure   is  thereby  diluted.    Coastal  areas
     have  been divided  by  the  National  Marine  Fishery
     Service (NMFS)  into reporting  areas for reporting on
     data  on  seafood landings.  Therefore  it was conven-
     ient  to express  the  total  area  affected by sludge
     disposal  as  a  fraction  of  an NMFS  reporting  area.
     The  area  used  to represent the disposal impact  area
     should  be  an approximation  of the  total  ocean  area
     over  which  the  average  concentration  defined  by
     Index  2  is  roughly  applicable.  The average rate of
     plume  spreading  of  1 cm/sec  referred  to  earlier
     amounts to approximately  0.9 km/day.  Therefore, the
     combined  plume  of  all  sludge  dumped  during  one
     working day  will gradually spread,  both parallel to
     and  perpendicular  to  current  direction, as  it  pro-
     ceeds  down-current.    Since  the   concentration  has
     been  averaged   over  the  direction  of  current  flow,
     spreading  in this  dimension will  not  further reduce
     average concentration; only  spreading in the perpen-
     dicular dimension will reduce the  average.   If  sta-
     ble  conditions  are  assumed over a  period of  days, at
     least  9 days would  be  required to  reduce the average
     concentration by one-half.   At that time,  the origi-
     nal  plume  length of approximately  8 km (8000 m)  will
     have   doubled    to   approximately   16 km   due   to
     spreading.

     It   is  probably  unnecessary  to   follow  the  plume
     further  since   storms,  which  would  result   in  much
     more  rapid dispersion of  pollutants  to  background
     concentrations  are  expected   on  at  least  a  10-day
     frequency   (NOAA,   1983).     Therefore,  the   area
                    3-11

-------
      impacted by  sludge  disposal  (AI,  in  km2) at  each
      disposal site  will be  considered  to  be defined  by
      the  tanker  path  length  (L)  times  the distance  of
      current- movement (V) during  10  days,  and is computed
      as follows:

           AI = 10 x L x V x 10~6 -km2/m2          (1)

      To be consistent with a  conservative  approach,  plume
      dilution  due  to  spreading   in   the  perpendicular
      direction  to  current  flow  is  disregarded.    More
      likely, organisms  exposed to  the  plume in the  area
      defined by equation 1 would  experience  a TWA  concen-
      tration  lower  than  the  concentration   expressed  by
      Index 2.

      Next,  the   value  of   AI  must  be  expressed   as   a
      fraction of an NMFS reporting area.   In the New York
      Bight, which  includes NMFS  areas  612-616  and  621-
      623,    deep-water   area   623    has   an   area   of
      approximately 7200 km2 and constitutes  approximately
      0.02  percent  of  the  total seafood  landings for  the
      Bight (CDM,  1984c).  Near-shore area  612 has an area
      of   approximately    4300   km2    and    constitutes
      approximately  24  percent   of    the  total   seafood
      landings (CDM,  1984d).    Therefore  the fraction  of
      all  seafood   landings   (FSt)  from  the  Bight   which
      could  originate  from  the  area of  impact  of  either
      the typical  (deep-water)  or  worst  (near-shore)  site
      can  be  calculated   for  this   typical  harvesting
      scenario as  follows:

      For the typical (deep  water)  site:

      __    AI x 0.02% =                                (2)
      tbt ~ 7200  km-'

[10 x 8000 m x 9500 m  x  IP"6  km2/m2]  x  0.0002 a 2 1  x 10~5
                   7200 km2

      For the worst (near shore) site:
               x 242
      FSt =
            4300  km2
  [10 x 4000 m x 4320 m x  10~6  km2 7m2]  x  0.24    _  ,    ,._>
                                  2-             = 9.o  x  10  J
                  ,^w 

      To construct  a worst-case  harvesting  scenario,  it
      was  assumed  that  the total  seafood consumption  for
      an individual  could  originate  from  an  area  more
      limited  than  the  entire  New  York  Bight.     For
      example,  a particular fisherman providing  the  entire
      seafood  diet  for  himself  or  others   could   fish
                    3-12

-------
          habitually within a  single NMFS reporting area.  Or,
          an   individual   could   have   a   preference   for   a
          particular  species  which  is  taken only  over  a more
          limited  area,  here  assumed  arbitrarily  to  equal an
          NMFS  reporting  area.    The  fraction   of  consumed
          seafood  (FSW)  that  could originate  from  the  area of
          impact under  this  worst-case  scenario  is calculated
          as follows:

          For the typical (deep water) site:

          FSW = 	AI  .  = 0.11                       (4)
                7200 km2

          For the worst (near shore) site:

          FSW = 	^r- = 0.040                       (5)
            w   4300 km2

     d.   Bioconcentration factor  of  pollutant  (BCP)  -  Data
          not immediately available.

     e.   Average  daily  human  dietary  intake  of  pollutant
          (Dl) - Data not immediately available.

     f.   Cancer potency - Data not immediately available.

     g.   Cancer   risk-specific   intake   (RSI)   -  Data   not
          immediately available.

          The RSI  is  the  pollutant intake  value  which  results
          in  an  increase  in  cancer  risk  of  10~&   (1  per
          1,000,000).   The  RSI  is  calculated from  the  cancer
          potency using the  following formula:

          RSI =  10"6  x  70 kg  1Q3 ug/mg
                        Cancer potency

4.   Index 4  Values  - Values  could not  be calculated due  to
     lack of data.

5.   Value Interpretation -  Value  >1 -would indicate a  poten-
     tially toxic hazard for humans.  Comparison  with the  null
     index  value  at  0 mt/day would  indicate the degree  to
     which any hazard is due to  sludge disposal,  as opposed  to
     preexisting dietary sources.

6.   Preliminary Conclusion  - Conclusion was not  drawn because
     index values could not be  calculated.
                        3-13

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                              SECTION 4

        PRELIMINARY DATA PROFILE FOR TETRACHLORODIBENZOFURANS
                      IN MUNICIPAL SEWAGE SLUDGE
I. OCCURRENCE

   The halogenated dibenzofurans (DBFs) entered
   the environment as unintentional impurities
   in polychlorinated biphenyls (PCBs) and prod-
   ucts derived from chLorophenols and chloro-
   benzenes, as well as being pyrolysis and
   photochemical products of PCBs and probably
   polychlorinated diphenylethers (PCDPEs).  The
   alky! DBFs and unsubstituted DBFs are pyroly-
   sis products of coal conversion.  Both alkyl
   and halogenated DBFs have been implicated as
   resulting from trace residues of fire, most
   notably incineration of anthropogenic wastes.

   A.  Sludge

       Data not immediately available.

   B.  Soil - Unpolluted

       Data not immediately available.

   C.  Hater - Unpolluted

       2.4 x 10~6 pg/L interim ambient water
       criterion for protection of human health
       from the toxic properties of halogenated
       DBFs ingested through water or contaminated
       aquatic organisms.

   D.  Air
 U.S.  EPA,  1982b
 (p. vi)
U.S. EPA, 1982b
(p. 1-2)
       No data available on ambient  concentrations
       of DBFs.

       A sample of  polychlorinated biphenyl  (PCB)
       was shown to contain si.25 ppm TCDF.
       If the ratio of  TCDF to  PCB is assumed
       to be the same in air as in the measured
       PCB,  and the ambient air concentration  of
       PCP is /*100 ng/m3,  then an ambient air
       concentration of 0.0000001 yg/m3 TCDF can
       be estimated.

       Fly ash contains traces  (100  ng/g or  less)
       of DBFs.
U.S. EPA, 1983
(p. 3-3)
U.S. EPA, 1982b
(p. 13-2)
                                 4-1

-------
        0.3 and 0.1 Ug/g PCDFs in 2 fly ash            Buser et al.,
        samples from a municipal incinerator           1978 (p. 426)

        Flue gas has been shown to contain PCDFs.      Buser et al.,
                                                       1978 (p. 428)

    B.  Food

        TCDFs have been detected in fish               U.S. EPA, 1983
        collected from the Ohio and Hudson Rivers.     (p. 3-1)
        An estimate of dietary consumption of
        2,3,7,8-TCDF resulting from fish consump-
        tion equals 0.2 yg/day.

II. HUMAN EFFECTS

    A.  Ingestion

        1.  Carcinogenic!ty

            a.  Qualitative Assessment

                There is no experimental evidence      U.S. EPA, 1983
                to suggest that any of the halo-       (p. 5-1)
                genated dibenzofurans are carcino-
                genic.  However, the similarities
                in structure, and biological
                effects between TCDDs, which are
                regarded as being carcinogenic,
                and TCDFs raise the suspicion that
                TCDFs may be carcinogenic.

            b.  Potency

                Data not immediately available.

            c.  Effects

                Data not immediately available.

        2.  Chronic Tozicity

            a.  ADI

                Data not immediately available.

            b.  Effects

                Approximately 1,200 Japanese people    U.S. EPA, 1983
                ingested rice oil which was acci-      (p. 5-5)
                dentally contaminated with PCBs
                (1000 ppm) and consequently PCDFs
                (5 ppm).  Individuals exhibited a
                variety of symptoms including fever,
                                  4-2

-------
                 headaches, spasms of hands and feet,
                 skin eruptions and discoloration
                 of skin and mucosa.

         3.  Absorption

             Rats receiving a single intraperitoneal
             injection of a PCDF mixture, exhibited
             complete hepatic retention of the
             dosed 2,3,7,8-TCDF component 5 days
             after the initial administration.

         4.  Existing Regulations

             Data not immediately available.

     B.  Inhalation

         Data not immediately available.

III. PLANT EFFECTS

     "No data could be found concerning effects of
     chlorinated dibenzofurans on plants."

 IV. DOMESTIC ANIMAL AND WILDLIFE EFFECTS

     A.  Toxicity

         PCDFs have not been studied in model
         ecosystems and there are very few data
         available on wildlife.

         "While specific causative agents cannot be
         assigned to effects observed in poisoning
         incidents, the available data do indicate
         that adverse effects may be expected to
         result from exposure of domestic animals to
         DBFs."

         <3Z of the PCDFs given in the diet over
         one year accumulated in tissues of mallards.

         See Table 4-1.

     B.  Uptake

         Data not immediately available.
U.S. EPA, 1983
(p. 4-2)
U.S. EPA, 1982b
(p. 8-1)
U.S. EPA, 1982b
(p. 5-3)
U.S. EPA, 1982b
(p. 9-1)
Norstrom et al.,
1976 (p. 7-1)
                                   4-3

-------
  V. AQUATIC LIFE EFFECTS

     A.  Toxicity

         1.  Freshwater

             a.  Acute

                 Toxicicy value for one inverte-
                 brate species = 1700 Ug/L.

             b.  Chronic

                 Data not immediately available.

         2.  Saltwater

             a.  Acute

                 Toxicity value for one species
                 of marine fish = 1800 Ug/L.

             b.  Chronic

                 Data not immediately available.

     B.  Uptake

         Data not immediately available.

 VI. SOIL BIOTA EFFECTS

     A.  Toxicity

         "No data could be found concerning the
         stability of chlorinated dibenzofurans to
         microbes, or if chlorinated dibenzofurans
         exerted toxic effects."

         Chlorinated dibenzofurans substituted at the
         8-position appear to be bactericidal.
U.S. EPA, 1982b
(p. 11-8)
U.S. EPA, 1982b
(p. 11-8)
U.S. EPA, 1982b
(p. 7-1)
U.S. EPA, 1982b
(p. 7-1)
     B.  Uptake

         Data not immediately available.

VII. PHYSICOCHEMICAL DATA FOR ESTIMATING  FATE AND TRANSPORT
     DBF water solubility:   3 mg/L at  2SC
     DBFs quite soluble in  organic solvents
     TCDFs melting point:   169 to  228C
     DBF octanol-water partitioning coefficient:   1,527
     DBF boiling point:  287C at  760  mm Hg
U.S. EPA, 1982b
(Chapter 2)
                                   4-4

-------
TCDFs vapor pressure:  (1.8 to 2.5) x  10~6 torr
  at 25C (estimated)
DBF specific gravity:  1.0886
Higher DBFs are degraded by light

At present, virtually nothing is known about       U.S. EPA, 1982b
the dynamics of PCDFs in the environment.          (p. 5-1)
                              4-5

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                                        TABLE 4-1.  TOXICITY OP DIBENZOFURAN TO DOMESTIC ANIMALS AND WILDLIFE
Species (N)*
Guinea Pig
Mouse/Rat
Rhesus Monkey
Monkey
Chicks
Chicks
Mouse (10)
Mouse (10)
Mouse (10)
Mouse (10)
====^==:^=^====
Feed
Chemical Concentration
Form Fed 6
1
	
0.001
0.005
30.0
44-67
100-150
225
Duration
of Study
	
	
	
6 mos.
21 days
21 days
30 days
30 days
30 days
30 days
Effects
LD50
LD50
LD50
2 of 3 monkeys died
16 percent mortality
100 percent mortality
OZ mortality
10Z mortality
30Z mortality
45Z mortality
~
References
U.S. EPA, 1982b
U.S. EPA, 1982b
U.S. EPA, 1982b
U.S. EPA, 1982b
McKinney et al.
(p. 12-23)
McKinney et al.
(p. 12-23)
Nishisumi, 1978
(p. 68)

(p. 12-1)
(p. 12-1)
(p. 12-1)
(p. 12-1)
, 1976
, 1976


a N  number of experimental animals when reported.
D TCDF = Tetrachlorodibenzofuran.
c PCDPs = Polychlorinated dibenzofurans.

-------
                                SECTION 5

                               REFERENCES
Buser, H. R., H. Bosshardt, C. Rapp, and  R.  Lindahl.   1978.  Identifica-
     tion of  Polychlorinated  Dibenzofuran  Isomers  in Fly  Ash  and  PCB
     Pyrolyses.  Chemosphere 5:419-29.

Camp Dresser  and  McKee,  Inc.  1984a.   Development of  Methodologies  for
     Evaluating Permissible  Contaminant  Levels  in Municipal  Wastewater
     Sludges.   Draft.   Office of  Water Regulations and  Standards,  U.S.
     Environmental Protection Agency, Washington, D.C.

Camp Dresser  and  McKee,  Inc.  1984b.   A Comparison of Studies  of Toxic
     Substances in  POTW  Sludges.   Prepared  for U.S. EPA  under  Contract
     No. 68-01-6403.  Annandale,  VA.   August.

Camp Dresser  and  McKee,  Inc.  1984c.   Technical Review of  the  106-Mile
     Ocean  Disposal Site.   Prepared  for U.S.  EPA under  Contract  No.
     68-01-6403.  Annandale, VA.   January.

Camp Dresser  and  McKee,  Inc.   1984d.    Technical  Review  of the 12-Mile
     Sewage Sludge  Disposal  Site.   Prepared for U.S.  EPA  under  Contract
     No. 68-01-6403.  Annandale,  VA.   May.

City  of New  York  Department  of  Environmental Protection.   1983.    A
     Special  Permit  Application  for  the  Disposal  of Sewage Sludge  from
     Twelve New York  City  Water  Pollution Control Plants  at the 12-Mile
     Site.  New York, NY.  December.

Farrell,  J.  B.     1984.    Personal  Communication.    Water Engineering
     Research   Laboratory,    U.S. Environmental   Protection    Agency,
     Cincinnati, OH.  December.

McKinney, J.  D.,  K.  Chae,  N. Gupta et al.   1976.   Toxicological Assess-
     ment of  Hexachlorobiphenyl  Isomers  and  2,3,7,8-Tetrachlorodibenzo-
     furan in Chicks.  Toxicol. & Appl. Pharmacol.   36:65-80.

National  Oceanic  and Atmospheric  Administration.    1983.    Northeast
     Monitoring  Program  106-Mile  Site  Characterization   Update.    NOAA
     Technical  Memorandum  NMFS-F/NEC-26.   U.S.-  Department of  Commerce
     National Oceanic and Atmospheric Administration.   August.

Nishisumi, M.   1978.   Acute  Toxicity of Polychlorinated Dibenzofurans in
     CF-1 Mice.  Toxicol. & Appl.  Pharmacol.   45:209-212.

Norstrom,  R.  J.,  R. W.   Risebrough,   and  D.  J.  Cartwright.    1976.
     Elimination    of    Chlorinated    Dibenzofurans    Associated   with
     Polychlorinated  Biphenyls  Fed   to  Mallards   (Anas   platyrynchos).
     Toxicol. & Appl.  Pharmacol.   37:217-228.

Stanford  Research  Institute International.   1980.   Seafood Consumption
     Data Analysis.  Final Report, Task  II.  Prepared  for  U.S.  EPA under
     Contract No. 68-01-3887.  Menlo  Park, CA.   September.

                                   5-1

-------
U.S. Environmental Protection  Agency.   1979.   Industrial  Source Complex
     (ISC)  Dispersion Model  User  Guide.    EPA  650/4-79-30.   Vol.  1.
     Office  of  Air  Quality Planning  and  Standards,  Research  Triangle
     Park, NC.  December.

U.S.  Environmental  Protection  Agency.     1982a.     Fate  of  Priority
     Pollutants  in Publicly-Owned  Treatment Works.   EPA 440/1-82/303.
     U.S.  Environmental  Protection Agency, Washington, DC.

U.S. Environmental Protection  Agency.   1982b.  Multimedia Water Quality
     Criteria Document for: Dibenzofuran.   Preliminary Draft  Document.
     ECAO-CIN-D007.   U.S.  Environmental  Protection Agency,  Cincinnati,
     OH.

U.S. Environmental Protection  Agency.    1983.   Health and Environmental
     Effects  Profile  for:  Tetra-,  Penta-,  and  Hexachlorodibenzofurans.
     Program  Office   Draft.     ECAO-CIN-P003.     U.S.   Environmental
     Protection Agency, Cincinnati, OH.
                                   5-2

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                                APPENDIX

   PRELIMINARY HAZARD INDEX CALCULATIONS FOR TETRACHLORODIBENZOFURANS
                       IN MUNICIPAL SEWAGE SLUDGE
  I. LANDSPREADING AND DISTRIBUTION- AMD-MARKETING

     Based on  Che recommendations  of  Che experts  at the  OWRS  meetings
     (April-May,   1984),  an  assessment of  this  reuse/disposal option  is
     not being conducted at  this  time.   The U.S. EPA reserves  the right
     Co conduct such an assessment for this option in the future.

 II. LANDPILLING

     Based on  the recommendations  of  the experts  at the  OURS  meetings
     (April-May,   1984),  an  assessment of  this  reuse/disposal option  is
     not being conducted at  this  time.   The U.S. EPA reserves  the right
     to conduct such an assessment for this option in the future.

III. INCINERATION

     A.  Index of Air Concentration Increment Resulting  from Incinerator
         Emissions (Index 1)

         1.  Formula

             T .    .    (C x PS x SC x FM x DP)  + BA
             Index l = -  -


         where:

             C =  Coefficient to correct  for mass and time units
                 (hr/sec x  g/mg)
            DS =  Sludge feed rate  (kg/hr  DW)
            SC =  Sludge concentration  of  pollutant (ing /kg DW)
            FM =  Fraction of pollutant emitted through stack (unitless)
            DP =  Dispersion  parameter  for estimating maximum
                 annual ground level concentration (ug/m^)
            BA =  Background  concentration of  pollutant in urban
                 air (yg/m3)

          2.    Sample Calculation  - Values  were  not  calculated due  to
               lack of data.

     B.  Index  of  Human  Cancer  Risk  Resulting   from  Inhalation  of
         Incinerator Emissions (Index  2)

         1.  Formula

                       [(Ii  - 1) x BA]  + BA
             Index  2
                                  A-l

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            where:

              II =  Index 1  = Index of air concentration increment
                   resulting from incinerator emissions
                   (unitless)
              BA =  Background concentration of pollutant in
                   urban air (yg/m^)
              EC =  Exposure criterion (yg/m^)

        2.  Sample  Calculation - Values were not calculated  due  to lack
            of data.

IV.  OCEAN DISPOSAL


    A.   Index of Seawater  Concentration  Resulting  from Initial  Mixing
        of Sludge (Index 1)

        1.  Formula

            T j    i     SC x ST x PS
            Index 1 = 		;	
                        W x D x L

            where:

                SC  =  Sludge concentration of pollutant (mg/kg DW)
                ST  =  Sludge mass dumped by a single tanker (kg WW)
                PS  =  Percent solids  in sludge (kg DU/kg WW)
                W  =  Width of initial  plume dilution (m)
                D  =  Depth to pycnocline  or effective depth  of  mixing
                      for shallow water site (m)
                L  =  Length of tanker  path (m)

        2.  Sample  Calculation - Values were not calculated  due  to lack
            of data.

    B.   Index of Seawater  Concentration Representing a  24-Hour  Dumping
        Cycle (Index 2)

        1.  Formula

                       SS x SC
            Index 2 =
                      V  x  D  x  L

            where:
                   SS  =  Daily  sludge  disposal  rate  (kg DW/day)
                   SC  =  Sludge concentration of  pollutant  (mg/kg  DW)
                   V  =  Average  current  velocity at  site (m/day)
                   D  =  Depth  to   pycnocline  or  effective  depth   of
                        mixing for  shallow  water site (m)
                   L  =  Length of tanker path  (m)
                                 A-2

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     2.   Sample  Calculation -  Values  were  not  calculated  due  to
          lack.

C.   Index of Tozicity to Aquatic Life (Index 3)
     1.   Formula


          Index 3 = AWQC-

          where:

            1} =  Index   1   =   Index   of   seawater   concentration
                  resulting   from  initial   mixing  after   sludge
                  disposal (yg/L)
          AWQC =  Criterion or  other  value expressed as  an  average
                  concentration  to protect  marine  organisms  from
                  acute and chronic toxic effects (ug/L)

     2.   Sample  Calculation  -  Values  were not  calculated due  to
          lack of data.

D.   Index of  Human  Cancer Risk Resulting from Seafood Consumption
     (Index 4)

     1.   Formula

                     (12 x BCF  x 10~3  kg/g x FS x QF) + DI
          Index 4 =  		


          where:

          12 =  Index   2   =    Index   of   seawater   concentration
                representing  a 24-hour dumping cycle (yg/L)
          QF =  Dietary consumption of seafood (g WW/day)
          FS =  Fraction of  consumed   seafood  originating from  the
                disposal site (unitless)
          BCF = Bioconcentration factor of pollutant (L/kg)
          DI =  Average  daily  human   dietary   intake  of  pollutant
                (lig/day)
          RSI = Cancer risk-specific intake" (yg/day)

     2.   Sample  Calculation  -  Values  were not  calculated  due  to
          lack of data.
                              A-3

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