Technical Report
                                         EPA 520/4-78-010
            RESPONSE TO COMMENTS:

         GUIDANCE ON DOSE LIMITS FOR
   PERSONS EXPOSED TO TRANSURANIUM ELEMENTS
          IN THE GENERAL ENVIRONMENT
                October, 1978
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

         OFFICE OF RADIATION PROGRAMS
       CRITERIA AND STANDARDS DIVISION   '•
           WASHINGTON, D.C.  20460

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                                    CONTENTS
    Listing of Respondents  to Federal Register Notice.	. ...ii

1.  Introduc tion	 .".	1
    Revised Text of Guidance Recommendations	...	3

2.  Response to Comments -  Summary Report
    2.1  Basic Guidance and Standards Philosphy	......5
    2.2  Risk Associated with the Guidance	12
    2.3  Economic Costs Associated with  the Guidance......:	25
    2.4  Implementation.	 . . .32
    2.5  Biological and Environmental Models	45
    2. 6  Miscellaneous Comments	52

3.  Response to Comments -  Annexes
    3.1 Annex 1	 ... .... .'.	67
    3.2 Annex 2	, ..		75
    3.3 Annex 3					100,
    3.4 Annex 4	......	..... r... ..,..152
    3. 5 Annex 5	 . 156
    3.6 Annex 6.	 .	.. ..172

4.  Estimated Costs of Remedial Actions	."......... .179

5.  Guidance implementation	199

6.  The Dose and Risk to Health due  to  the Inhalation
    and Ingestion of Transuranium Nuclides	 .207

7.  Rocky Flats Facility -  Technical Assessment Document		221

8.  Discussion of Comments  submitted by  Carl Johnson, M.D.,
    Director of Health, Jefferson County, Colorado..",. . ...--.	267
 Annex -  Department of Energy Comments  on Decontamination Costs
Discussed in the EPA Proposed Guidance on Dose Limits  for  Persons
Exposed to Transuramium Elements in the  General Environment

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           LISTING OF RESPONDENTS TO FEDERAL REGISTER NOTICE
1.   Tenneco Inc.

2.   Colorado Environmental Health
     Association

3.   Timothy E. Wirth, Congress of the
     United States

4.   Texas Deptartment of Health

5.   Ilene Younghein

6.   N.Y. Federation for Safe Energy

7.   Natural Resources Defense Council, Inc.

8.   Edward A. Kartell

9.   Colorado Department of Health

10.  Jefferson County Health Department

11.  Department of Defense
     (Defense Nuclear Agency)

12.  Nuclear Safety Associates

13.  Department of Energy

14.  Conference of Radiation Control
     Program Directors

15.  Center for Environmental Research
     and Development

16.  Commonwealth Edison (Chicago, Illinois)

17.  Nuclear Regulatory Commision

18.  National Council on Radiation Protection
     and Measurements
Date Received

13 Dec. 1977


27 Dec. 1977


 4 Jan. 1978

24 Jan. 1978

15 Feb. 1978

21 Feb. 1978

27 Feb. 1978

27 Feb. 1978

27 Feb. 1978

 1 Mar. 1978


 1 Mar. 1978

 1 Mar. 1978

 6 Mar. 1978


 7 Mar. 1978


16 Mar. 1978

24 Mar. 1978

24 Mar. 1978


27 Mar. 1978

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                            1.  INTRODUCTION
     The staff of the Office of Radiation Programs has evaluated all
comments received in response to publication of the proposed Federal
Radiation Protection Guidance on Dose Limits for Persons Exposed to
Transuranium Elements in the Environment (Federal Register Vol. 42,
No. 230, pages 60956-9, Nov. 30, 1977).  Responses to these comments
are given*in this publication.  The Agency concluded that the comments
received did not raise substantive new issues and that, therefore, the
proposed recommendations should be submitted to the President with
only minor changes for promulgation as guidance to all Federal
agencies.

     Comments and corresponding staff responses have been grouped,
insofar as possible, by major subject categories.  Responses are given
for specific comments as received, and are referred to the text, of the
Summary Report (EPA Publication 520/4-77-016).  In a few instances,
comments were very general and not applicable to the,proposed .
Guidance.  No staff responses have been provided for these.

     New or revised sections for the technical Summary Report document
have been -prepared on a number of different topics.  These follow the
Responses to Comments part of this report, and include a section on
the costs of remedial actions (based in large part on information
provided by the Department of Energy and the Nuclear Regulatory
Commission), a revised section on implementation, a discussion  of dose
rates and risks from soluble transuranium compounds, an assessment of
potential health risks to persons outside the boundaries of the Rocky
Flats Plant, and a staff analysis of a soil sampling and analysis
method proposed by Carl Johnson, M.D., Director of Health, Jefferson   ;
County, Colorado.

    , The comments as received by the Agency are not reproduced  here in
order to avoid unnecessary duplication.  Single copies are available
on request from the Director, Criteria and Standards Division,  Office
of Radiation Programs, ANR-460/CM#2, U. S. Environmental Protection
Agency Washington, D. C. 20460.                             -  ,  •.   .

     The Agency has made some minor changes in the -wording, of the
Guidance.  The revised text of the recommendations follows this
section.

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REVISED TEXT OF GUIDANCE RECOMMENDATIONS

     In order  to assure  the  protection  of  persons  in the general
population by  limiting the radiation  doses that  an individual  in a
critical  segment of  the  population may  receive from concentrations of
transuranium elements present above average background levels  in the
general environment, the following recommendations shall apply for the
guidance  of Federal  agencies:

     1.   The annual  alpha radiation dose rate to members of the
critical  segment of  the  exposed population as the  result of exposure
to transuranium elements in  the general environment should not exceed
either:
          a.  1 millirad  per  year  to the pulmonary  lung,  or
          b.  3 millirad  per  year  to the bone.

     2.   For newly contaminated areas,  the Federal agency responsible
for implementation should take immediate action  to minimize both the
residual  levels of transuranium elements in the  general  environment
and the radiation exposure of the general  public.   Determination and
implementation of appropriate measures  to  ensure compliance with the
above recommendations should begin as promptly as  possible and should
be completed within  a reasonable  period of time.

     3.   The recommendations are  to be  used only as radiation
protection guidance  for  presently existing cases of environmental
contamination by transuranium elements  and for possible  future cases
of environmental contamination from unplanned releases of transuranium
elements.  They are  not  to be used by Federal agencies as limits for
planned releases of  transuranium  elements  into the general environment.

DEFINITIONS

       "bone" means  osseous  tissue.  The average total weight  of this
tissue is assumed to be  5000 grams.

       "critical segment of  the exposed population" means that group
of persons within the exposed population who, because of residency or
other factors, can on the average be expected to receive the highest
lifetime  radiation dose  to the pulmonary region  of the lung or to the
bone from a specified source of environmental transuranium element
contamination.

       "general environment" means the  total terrestrial,  atmospheric
and aquatic environments outside the boundaries  of Federally licensed
facilities or outside the boundaries of sites which are  under  the
direct control of a Federal  agency.

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       "millirad  per  year  to  the  bone"  means  the dose rate attained
after 70 years of chronic  exposure.   This  dose rate is calculated by
dividing the alpha energy  absorbed  in the  bone during the 70th year by
the bone mass.

       "millirad  per  year  to  the  pulmonary lung" means the equilibrium
dose rate following chronic inhalation.  This  dose  rate is calculated
by dividing the alpha energy  absorbed per  year in the pulmonary lung
by its mass.

       "pulmonary lung" means  the region of the lung consisting of
respiratory btonchioles, alveolar ducts, atria, alveoli,  and alveolar
sacs.  The average total weight of  this tissue, including the
capillary blood,  is assumed to be 570 gms.

       "rad" is the unit of absorbed  dose,  defined  as the energy
imparted to tissue by ionizing radiation divided by the mass of the
tissue.  One rad  is equal  to  the  absorption of 100  ergs of radiation
energy per gram of matter.
     1 millirad (mrad) = 10~3 rad.

       "transuranium  elements" means  all chemical elements with atomic
number greater than that of uranium as  classified in the  Periodic
Table of Elements.

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               2.  RESPONSE TO COMMENTS - SUMMARY REPORT

2.1 Basic Guidance and Standards Philosophy

1.  Representative Timothy Wirth

     I see a need to question the form of the standards themselves.
Currently, the standards are based on the lifetime dose that a person
living in the area would receive.  It does not  look  at the  community
wide effect as a whole.  I am not sure that this is  the correct
approach to take.  For example, if the radiation contamination of  an
area was such that a person living there had one chance in  ten
thousand of getting cancer, but only fifty people lived in  the area,
the most likely number of extra cancer cases in the .country as a whole
would be zero as a result of this contamination.  If the  same
contamination was occurring in Manhattan, there could be  thousands of
additional cases.  The proposed standards do not address  that
problem.  But this is the problem that society  faces; not the
probability of cancer in a hypothetical person  that  will  result  from
radioactive contamination, but rather a probable number of  cancer
cases, depending on the population density of the area.   Unless  we
find cancer in.New York less offensive than cancer in New Mexico,  we
must adjust our  standards  to take into account  these population
density differences.  The  amount of emissions that are  acceptable  in
Manhattan really is lower  than in an unpopulated area.

     Thus, I think that the EPA should come up  with  a standard  that
says "this is  the number of probable excess cancer deaths that  we  are
willing  to tolerate from a government  facility."  The actual  numerical
standards for  any site will  then be  calculated  similarly  to your
current approach, but with the added factor of  population.

     The  advantage of  this approach  i§ obvious. It  gives citizens in
all parts of the country equal protection,  since  cancer deaths  are
giv
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  numerical risk limit as proposed is not intended to be viewed as an
  acceptable limit, but rather is to be interpreted as recommending that
  doses to individuals should be kept well below the limit and that
  exceeding the guidance values is unacceptable.  The maximum risk to an
  individual from lifetime exposure to transuranium element
  contamination was proposed on the basis of comparisons with other
  commonly accepted low probability risks.  The appropriateness of such
  a proposed risk limit is a subject for social judgment.

       Cumulative risks to a large population group were also considered
  in the  development of the guidance but,  because the estimated
  population dose commitments  for all existing sites  were small,  the
  guidance recommendations were based on the maximum risk to    '
  individuals.   The observation that population-impacts  should be
  considered in the decision making process  is a valid one.   However  if
  one were to limit the total  adverse impact at any site  to a given
  number  of fatalities  independent.of the  population  density,  then the
  guidance would  not provide equal  protection to  persons  in all sections
  of the  country.   The  Agency  has taken  this into consideration in its
  recommendations concerning  future  contamination, where it  recommends
  that remedial action  be  carried out  as soon as  possible after
 occurrence to a level as  low as reasonably achievable and with  the
 numerical guide as an upper  limit.   The  determination of a  level  as
 low as reasonably achievable would take  into  account the size of  the
 population exposed,, the  cumulative population dose as well as the
 costs of cleanup.  Therefore, both the individual and population risk
 are integral to the implementation of this  guidance.  In effect,
 therefore, the projected impact of a source in  terms of committed
 population dose or potential fatalities becomes the primary
 consideration in determining the range and scope of remedial actions
 within the constraint of assuring that individual dose rates not
 exceed the guidance recommendations.

 2.    Department of Energy
                                                '      )  -  -     i     ;
 n.  .  1*  . "It:  *s instructive  to compare the proposed EPA Guidance
 limits with...(those)...  recommended by other bodies...On the basis of
 these  comparisons  the- EPA proposed guidance could  be considered  to be
 unnecessarily  restrictive."

     Staff Response -  The comment  compares  the proposed  guides  to
 upper  limiting  doses for  the  general population from all sources
 combined  as recommended by ICRP, FRC, and NCRP.  These  groups all
 emphasized that  the recommended limits were upper  bounds; that within
 these, doses should be permitted only insofar as they could  be
 justified and were, in addition,	 as  low as  practicable  or as  low
 as reasonably achievable.   Too  often  these  recommended limits have
been treated as  defining  the  acceptable range  of exposure, (e.g.  like
 speed limits) and  this comment  falls  into the  same error.  The

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proposed EPA guides represent instead  a  judgment  of what exposure,
within .these boundsf, is acceptable  because it adequately limits the
risk to a critical segment of the population-and. is economically  ,, ..-;,v, '.,-
achievable.  Disagreement with  the  proposed guides should be based
upon the validity of EPA judgements on these latter two points, not on
the difference between the proposed guides and the limiting
recommendations of ICRP, FRC and NCRP.                           '

3.   Department of Energy

     "The EPA apparently adopts the position that the total
permissible radiation exposure  should  not  be allocated to a single
source or activity.  The ICRPj  however,  considers it quite appropriate
...If the EPA has embarked upon a policy, o£ apportionment...This
should «be clearly presented..."                            •       >

     Staff Response - EPA does  not  take  the.position that the general
dose limits are available for apportionment.  Neither does the ICRP;
they endorse^instead optimization of dose  reduction'from individual
sourcesj irrespective of contributions from other sources'>        •
(para. 121, ICRP^26).  Since the exposures governed by the proposed
guidance are likely to be chronic,  .the even more  restrictive          ::
considerations of para.  122 and para.  123  of ICRP-26 define •-ICRP1 s
view of suitable, boundary conditions on  dose (100 mrem/yr) from all
sources.  The question of. apportionment  is not germane to choosing an
optimized dose level for radiation  protection; it is only pertinent to
situations in which several relatively large doses may accrue to a
single individual from separate sources.  That situation does not
appear pertinent- to the  doses contemplated as acceptable by the
proposed guidance.                     ;                "

4.  Conference of Radiation Control Program Directors

     "..it is hoped that EPA will appropriately address the impact of
this standards and guidance on  the  apportioning of the 170 mrem/year
limit, or its reduced value."              .
  •;.    • •:.•  I     '-..   .: • '•••' ' '-  •    ' "   -  'I'".'    •  •     -''"' '• •    •  ••••'•'  '"' '" . '
     Staff Response - EPA will  address this matter .when and if it
appears to be a realistic problem.   At this point in time, it appears
highly improbable  that  the 4 mrem/yr drinking water limit, the 25
mrem/yr uranium  fuel, cycle ;limit and, the present  proposed guides could
result in combined doses .to a .real  individual' s organs which'even    \~
approach the sum of these three limits,  let alone the ,170 mrem/year
bound or any foreseeable, future .reduction of that limit.       :

5.   Department of Energy        .                                   , . ,

     It is not clear how this Guidance'will "offer much greaterv
protection to the vast majority of  the population at. lesser risk.'1
This vast majority receives no  protection nor does it require any.
(p-15, lines 20-24)

                                     7

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      Staff Response - We do not agree.  The proposed guidance
 establishes recommendations on an upper limit for exposures to the
 critical segment of the population by transuranium elements in the
 general environment.  By ensuring compliance with these
 recommendations, an upper level of risk is established.  Because most
 members of the general population are exposed to lower doses than the
 defined "critical segment," the vast majority of the population is at
 lower risk and afforded greater protection.

 6.    Department of Energy

      It would be useful to describe and document the "...different
 regulatory requirements,  constraints associated with remedial actions
 for  a particular carcinogen,  uncertainties in the calculations,
 differences in methods used to derive lifetime risks, and economic
 considerations."  This would  enable the user of this Guidance to
 understand the basis for  and  the considerations involved in this
 Guidance.   (p-16, lines 18-22)

      Staff Response - The content and basis of Federal  actions
 intended to regulate carcinogens are generally published in the
 Federal Register.  Because no  common basis presently exists for risk
 evaluations,  and there is no  agreement on  a level of "acceptable risk"
 applicable to all situations,  such comparisons do not serve a useful
 function.   As stated in the rationale for  the Guidance, there is a
 real  distinction between  actions intended  to achieve a  remedial rather
 than  preventive objective.  The best comparison available is with the
 contamination of the James  River with kepone,  but the .health and
 economic impacts of  the two situations are so  different that the
 decisions  made^for kepone cannot be applied directly to transuranium
 element  contamination.  The public  health  risks  associated  with the
 transuranium  guidance  recommendations are  generally  lower than those
 for most other  regulated  carcinogens.

 7.   Department of Energy

     The sentence on  page 16 makes  the very important point  that  the
Guidance is "applicable to  remedial  and  restorative  actions,  and must
be distinguished  from  risk  levels which  provide  for  a routine  level  of
acceptability;"  but  this  distinction  does  not  seem to have been
applied  in the  derivation of the Guidance.

     Staff Response - The statement  is intended  to convey the  idea   ..
that the level  of an "acceptable" risk is  generally lower for  a
preventive than for a  restorative situation.  The Agency  has not
evaluated  the factors which determine  the  appropriate level  of  risk
for routine and planned releases.
                                    8

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8.    Department of Energy
     Since dose limits are customarily expressed in units of rem,  it
seems unusual to find them expressed here in rad.  While an effort is
made to justify this in Annex III, many readers may never get  to Annex
III and it might be well to show the rem equivalents.   If this  is
done, the limits become 10 mrem/y to lung and  150 mrem/y to bone.   On
such a basis the limit to lung seems much more conservative than the
limit to bone.  This may be justified, in part, by the  more complete-
information on human bone risk, as discussed in Annex III.
(page 21, lines 3-4)

     Staff Response - The rad is the basic  unit of absorbed dose for
ionizing radiation, while the rem is a relative unit which modifies
the rad by the "relative biological effectiveness" for  the  specific
type of radiation.  Dose limits are best expressed in rad in  order to
avoid the ambiguity introduced by controversy  on  the "quality factor1'
for alpha radiation in different tissues (see  ICRP Publication 26).
In the development of this Guidance, the,comparability  of dose rates
to different organs is based on risk.

9.   Tenneco Inc.
      Shouldn't  the  absorbed  dose be given in terms of the SI derived
unit,  the becquerel (Bq)?  Similarly,  the absorbed dose rate unit   .
should be in grays  per  second (Gys/s).

      Staff  Response - The  Federal Register notice 42:206 pp 56513-4,
published by the Department  of Commerce,  which defines policy
regarding use of metric units in the United States, states that "in
those cases where their usage is already  well established, the use,
for  a limited time, of  the units (— curie, roentgeri, rad) is
accepted, subject to future  review."

 10.   Ilene  Younghein

      Much  is said in your  assessments about economics and practicality
but  nothing about suffering.  There is the suffering of parents with
 abnormal children,  the  suffering of men,  women, children and animals
 dying of lung,  bone and kidney cancer.

      Staff  Response - Suffering cannot generally be quantified in,   '
monetary terms, but is  certainly considered with respect to genetic
 defects and cancer mortality.  The rationale for the guidance is not
 based on any criteria related to the direct or indirect monetary costs
 of a human  life or to suffering and only uses economic analyses to  the
 extent necessary to show that compliance is feasible.

 11.   Ilene Younghein                                          '

      Let me comment on the report itself.  One, it is
 nameless-therefore blameless.  It appears  to be a whitewash, in trying

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                                     6
 to live with the mess we  already  have,  and  it  certainly  doesn't
 accurately access your  previous hearings.   Most  of  the reports are
 either middle of the road or  downplay the dangers of  plutonium.
 Reports by such scientists  as Samuel Milham, Thomas Mancuso,  Irvin
 Bross, Karl Morgan, John  Gofman and Arthur  Tamplin were  not included.
 Edward^Martell, who has done  extensive  research  or problems with
 plutonium at Rocky Flats,  didn't make the list either.   I  always want
 to know who writes the  reports, their positions, and  possible
 conflicts of interests.

      Staff Response - The proposed Guidance was  prepared by the staff
 of the Office of Radiation Programs and published after  review by the
 Administrator of EPA.  It therefore represents an Agency viewpoint
 rather than that of individuals.

      The Agency staff is  thoroughly familiar with the published
 reports of the scientists named and has considered their results in
 preparation of the Guidance to the extent appropriate.

 12.   Ilene Younghein

      In Annex 1,  p.9 you say "large areas outside the exclusion areas
 have  become contaminated with plutonium".  Compared to the age of the
 earth,  the last thirty years would be similar to a grain of sand on a
 beach.   At the  risk  of discussing ethics, I find it highly immoral
 that  in the last  few years we have permanently contaminated portions
 of this  earth - something that hasn't happened in the billions of
 years previously.  Is  this being weighed in your radiation standards
 and your environmental  impact statements?

      Staff Response  -  No.   The ethical  aspects  of releases of
 transuranium  elements  to the environment were not considered in
 developing the  guidance  recommendations.

 13.   Jefferson  County Health Department

      I am concerned with the criteria on page 60957  in the  first
 paragraph, Rationale for Guidance.  One  of  two  primary criteria used
 in developing this guidance,  "That any actions  required by
 implementation of the guidance be  practical  in  terms of overall
 economic requirements".  In view of the  nature  of the  guidance
 proposed, I feel that economic concerns  have really been  given
 foremost consideration,  perhaps with  intent  to minimize any economic
 impact^on federal agencies  or  private corporations which  have
 contaminated offsite lands.   It appears  to me that the concern for the
 public health has been given  lower  priority  here.

     Staff Response - The  order of  application of the  criteria has
been reversed in this comment.  The risk  to  an individual in the
                                  10

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critical segment of the population is the primary concern of  the
guidance.  Implementation was deemed to be practical  in  terms  of
overall economic requirements.
14.  Jefferson County Health Department

     I feel that the estimates in this proposed  guidance  of  deaths due
to cancer, the effects on longevity, and  the  genetic-effects cannot be'
conservative estimates.  As an illustration of the  present federal
nonr-conservative policy in regulating radiation  exposure, consider the
recent report of a significant increase in chromosome abnormalities in
plutonium (workers) permitted by federal  radiation  protection guides-.
The current radiation protection guides are simply  too high  to provide
adequate protection.  I disagree with the report in that  "realistic"
estimates must be made where there  is insufficient  knowledge.  Our
experience with radiation hazards over the past  fifty years  should  •
teach us that we must be prudent in evaluating radiation  hazards  and
that we must be conservative in establishing  radiation protection
guides.                                                '-•     .„.,  ':

   .  Staff Response ~ The Agency staff's  estimates  of,the relationship
between radiation dose and cancer mortality and  serious genetic
effects are not intended to be conservative but  rather to be realistic
estimates based on best available data.   The  degree Of conservatism •"
can only be established by comparison with  such  realistic estimates,
and is here based on introducing an "adequate margin of safety" in the
recommended dose rate limit for the "critical segment of  the
population".  On the basis of public comments received by the Agency,
we believe the judgment with respect to  the dose rate limit  and
associated maximum risk  to an individual  to be reasonable;     •>, .'

     The staff does not believe that previous Federal Guidance on
occupational expsoure has a bearing on guidance  levels for
transuranium elements in the general environment.        '     "-'\
                                   11

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 2.2  Risk Associated with  Guidance
 1.   Department of Energy

      The dose limits of  the Proposed Guidance  are  as  low  as  they  are
 for several reasons.  The EPA assumed  an  acceptable level of risk of
 slightly less than 10~6  per year.  The ICRP  (Publication  26) assumed
 an acceptable level of risk in the range  of  10~5 to 10~6  per year,
 and established its "individual member of the  public"  limit at a  level
 estimated to be equivalent to a risk of 5 x  1(T5 per year, assuming
 that the average exposure will not exceed 10%  of the limit.  This
 single factor of about 50 is enhanced in  the case  of lung by an EPA
 factor relating lung dose and cancer risk that is  larger than the
 corresponding ICRP factor, but is largely cancelled in the case of
 bone by an EPA dose-risk factor smaller than the ICRP factor.

      Staff Response - EPA has not assumed an '"acceptable" level of
 risk.   The Agency recognizes that the stated level of unacceptable
 risk,  i.e.  greater than 10~6 per year, is about the same as the
 lowest value given in ICRP Publication 26, and that there are some
 differences in factors  assigned to risk conversions from those
 reported in ICRP-26.   In view of the fact that the ICRP system of dose
 limits applies to  the doses received from a variety of sources,  and
 not a  single source such as dealt with by EPA,  the differences are
 considered  reasonable for the environmental problems currently faced.

 2.   Conference of  Radiation Control  Program Directors

     The text  of  the  proposed guidance was developed using widely
 accepted procedures in  ascertaining  radiation doses and dose  rates and
 the related  health risk.   The level  of acceptable risk has been  used
 before;  however, not  to  the  extent used in this document.   The  level
 of  risk  deemed  acceptable by  EPA  in  this  guidance appears  to  be
 arbitrary in view  of  the  levels of transuranics in  the  general
 environment.  Stronger wording  than  that  provided in the  text of  the
 guidance must be provided to  the  effect  that  the  "levels must be  as
 low as reasonably  achievable  with available  technology".   This would
 provide  for  the use of lower  level standards  where  the  situation would
 allow, i.e.  Colorado.  It is  also  a reasonably  conservative approach
 for  the  implementation of the guidance as  it  is finally adopted.

     Staff Response - The EPA staff has not assumed an "acceptable"
 level of risk.  The recommended maximum risk  of 10~6 is judged by
 the Agency to be such that any risk significantly greater would be
unwarranted  and therefore unacceptable.  Such determinations must  rely
 on judgments, since no means exist for deriving an  "acceptable" level
of risk for non-threshold pollutants.  The Agency does not believe
that the stated level of risk is large; it is certainly comparable
                                  I

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with risks associated with many other pollutants and food additives
which are believed to be carcinogenic.  In practice, it is anticipated
that no person will be exposed to the limiting risk but that exposures
will be.at levels substantially lower, even  for those  f&w individuals
in the critical segment of the population.

3.   National Council on Radiation Protection and Measurements

     The derivation of the risk values used  in setting these limits  is
poorly explained.  Comparison is made between real risks that  involve
large numbers of people with hypothetical risks that involve only  a
small part of the population.

     We recommend that the derivation of this risk of  10 x  10~5 per
lifetime be  reexamined and justified on the  basis of the population
size, uncertainty in  the value,, economic costs, environmental  cpsts,
and human costs.

     Staff Response - The Agency  staff has not made  a  distinction
between "real"  risks  and "hypothetical" risks.  The  population dose
has not been used as  a rationale  for  the guidance  levels;  rather,  the
guidance  levels were  based on  judgment with  respect  to the  level of
risks  to  individuals.

     The  factors  suggested in  this  comment have  been considered with
respect  to  the  lifetime risk associated with the  guidance  levels.
Population  size is  not  included because  risk takers  (with  respect to
this  guidance)  can  be individually  identified and the  Agency has? the
responsibility  of protecting these  individuals.   Uncertainties in risk
estimates  are  recognized,  but  they  were  not  judged so  large as to
prevent  the issuance  of  guidance.   Costs  (economic,  environmental and
human)   were not  directly  part of the guidance rationale,  but were
considered  to  the extent  necessary to show that the guidance could be
 implemented.                           -

4.   Colorado Department of Health

      While the  risk associated with proposed guidance appeared to be
well below other risks experienced by the general population as
 depicted by Annex IV, if the situation can be controlled then  this
must be done,  i.e., as low as  reasonably achievable by available
 technology.  Therefore,  if the State of Colorado can  justify that
 their more conservative standard is reasonable for the situation that
 currently exists within the State, then that standard or lower
 achievable levels must be applied.  Depending on the method of
 comparison, the current Colorado standard for Plutonium-in-Soil is  a,
 factor of 70 •*• to 150 times lower or more conservative than the
 proposed EPA guidance.
                                    O

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       Staff Response - EPA believes that the practice of reducing
  exposure to levels "as low as reasonably achievable" in accord with
  the long existing practice in radiation protection has merit and is to
  be encouraged.   The State of Colorado may be able to establish more
  stringent requirements than Federal Guidance if it so desires
  Federal guidance is only directed to the Federal agencies and'their
  programs to assure the health and safety of the public.

       Comparisons between the Federal Guidance  and the Colorado
  standard are inappropriate because they have an entirely  different
  objective and specify  different  implementation procedures.   The
  a0i^n°-Stand^rd " intend?d to  Protect construction workers and sets
  a plutonium soil  concentration level  which,  if exceeded,  requires that
  special  protective  actions  be considered.   The Federal Guidance, on
  the other hand,  designates  a dose  rate  to persons  in  the  general
 population which  serves as  a limit  for  exposure  to transuranium
 elements  in  the  general environment.  The Colorado standard  and the
 Federal Radiation Guidance  therefore  can be viewed as complementary
 and serving  different purposes.                              cucaty
 5.
Center for Environmental Research and Development
      I urge you to publicize widely what exactly it is you are
 proposing.   You are proposing to allow polluters to ignore alpha
 activity below 4400 dpm/100 Cm2 background in all the situations
 described in EPA 520/4-77-016.   However, you present considerable
 evidence that background is 40  dmp/100 cm2 or perhaps
 4 dmp/100 cm* (for example, pags.  3,  5;  Annex 1, pgs, 3,  4,  5)
 Thus  the contamination you are  proposing to allow is higher  than
 background  by a factor of from  100 to 1000.  On the face  of  it
 terming  such levels of contamination  "acceptable" is a travestv of
 environmental protection.                               "
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                               <.,*- 4
6.    Tenneco
                      .- '.  "     - •       . -    >-.' .''.:'.- •&'•     •   ,
     I agree with the concept of looking at  acceptable  risk  rather
than.taking the; approach that no exposure  is  to be allowed because
someone may contract  a disease and die.  I personally .believe  that
such "lowest feasible level" controls are  doomed  to  extinction because
of the realities of life.  There are  finite  risks .associated with all
human endeavors.  Cigarette smokers and seat  belt non-users  certainly
seem to comfirm that  people are willing to accept risks.  . I  should
hope that statutory standards consider the "big picture"  when.levels
are set that may become infeasible,.due to  real economic, considerations'.

     Staff Response - The agency staff agrees with this;comment,  to
the extent of recognizing that mandating of  a zero risk concept is
inappropriate and not feasible.  However,  it believes  that government
has an obligation to  its citizens to  provide maximum protection of
health, safety, and welfare within the constraints of  economic and
social considerations.

7.  Jefferson County  Health Department

     In the second paragraph under Rationale for  Guidance, reference
is made to the exposure of all persons to  "a large number of competing
risks", which implies somehow  that because of other  risks to health
that the risk of health from radiation is  made  somehow;,acceptable.

     I believe that the expression "competing risk"  is used
inappropriately on page fifteen  (2nd  paragraph), and  elsewhere. , The, :
use  of the expression here implies that radiation exposure is not very
important because of  .other "competing risk". I  think  we  must consider
all  risks to health as additive  or perhaps potentiating rather than ,
"competing" i.e., asbestos workers and uranium miners  who also smoke
cigarettes have much  more  severe effects  than merely adding risk
factors together.  The term "competing risks" implies  that one adverse
effect somehow ameliorates another adverse effect.

     Staff Response - The  comment misinterprets  the  use of the term
"competing risks" if  it  implies  that  this  has. been used to make the
radiation risk acceptable.  The  term  "competing risks", as used here,
expresses the  fact that  all persons are  continuously subjected to a
 large number of risks that compete for  the deaths of all  individuals.
The  removal of any one of  these  competing risks (e.g.  heart disease)
 results in an  increased risk  of  death from other causes of death-  .The
 introduction of a new cause of death  (e.g. exposure  to transuranium
 elements) reduces the number  of  deaths  from  other causes, but at the
 same time other causes of  death will  take the lives  of some of the
 individuals otherwise destined to die of  the new cause of death (in
 this case, exposure  to  transuranium  elements),  thereby reducing its
 apparent risk.  The  intent of  the calculation of competing risk jLs  to
 give the reader  some  perspective on  the  magnitude of the additional
 risk of death  to  an  individual from  exposure to transuranium elements
 at  the  guidance  limit.
                                       IS

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  8.    Jefferson County Health Department

       It must be noted that the proposed annual alpha radiation dose
  rate  to the public living in such contaminated areas (one millirad per
  year  to the pulmonary lung or three millirad per year to bone) will
  result, on the basis  of animal studies, in 20 millirem to lung, 960
  millirem to trachiobronchial lymph nodes,  60 millirem to bone, 20
  millirem to liver,  4  millirem to  the kidney and one millirem to
  gonads.  These may be contrasted  with the  radiation dosage limits
  established by the 1976 EPA Water Regulations which limit the exposure
  of  the  general public to no more  than 4 millirem per year from
  man-made beta and photon emitters".   A millirem is a term developed
  to  consider biological  effectiveness  and organ distribution of
  different types of  radiation,  and make them comparable  in terms of
  health  effects.  As you can see there is a marked discrepancy between
  the proposed guidance levels  and  the  regulations  promulgated last year.

      I  am puzzled  at  the  non-conservative  guidance  proposed  by the
 EPA.  I thought the maximum radiation levels  established  by  the EPA
 Water Regulations were  commendable and well-supported,  and reflected
 concern for public health.  This  is not  true  of the  proposed
 guidelines.

      Staff Response - The basis and rationale of  the EPA Drinking
 Water Regulations and the Guidance for Transuranium Elements  are
 entirely different and not comparable.  The four millirem annual  limit
 in the Drinking Water Regulations  is given as the maximum contaminant
 level  only for man-made beta and photon-emitters in finished drinking
 water.   The biological risk from alpha emitters differs markedly,  so
 that a direct comparison in terms  of absorbed dose is not
 appropriate.  The Drinking Water Regulations specify a limit of 15
 pCi/liter of gross alpha contamination which, at an intake of 2
 liters/day, is  equal to 1.1 x 104  pCi/year.  For soluble
 transuranium elements, where a transfer fraction of 1 x 10~3 is
 conservatively  assumed,  this intake can be  equated to about 0 5
 mrad/year to bone.   Noting the fact that drinking water represents a
 single ingestion pathway while the proposed guides refer to food,
 water, and inhalation,  the limiting dose rates for the Drinking Water
 Regulation and  the Guidance for Transuranium Elements are comparable
 with respect to the risk to the individual.

 9-   Jefferson  County  Health Department

     I disagree with the third paragraph under Rationale for  Guidance
 in^that  I  believe  the  estimated risk  is  understated,  that  is,  in my
 opinion  considerably more  than a hundred  cases of  cancer per  million
would occur  as  a result  of  exposure to  the  proposed  guidance  level.
The guidance acknowledges  this  in  part  by saying "It  must  be
 recognized  that these estimates are not precise, and  have  an

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uncertainty of at least a factor of three for cancer risks".  I
believe we must allow for these "uncertainty factors" and establish
lower guidance levels than have been proposed.  In the first paragraph
on page 60958 the guidance states "Additional risks may result from
transiocation of a small fraction of the transuranium elements in the
lung to other body organs, especially to the liver and bone".
Research with animals indicates that much more than a "small fraction"
of plutonium retained in the lung is translocated to the bone.   In the
same paragraph, reference is made to hypothetical cohort of  100,000
persons receiving an annual average dose rate to pulmonary tissue of
one millirad per year per person, which could potentially result in
ten premature cancer deaths, or a hundred premature cancer deaths per
million.  Birth defects and general adverse effects-on health due to
chromosomal damage must also be considered.

     The proposed guidance level of 3 millirads to bone  is estimated
to "potentially result in less than six premature deaths from such
cancers per 100,000" (or 60 deaths per million).  However, this
estimate is particulary controversial since estimates of such effects
vary widely.  In the third paragraph on this page, concerning genetic
damage, the guidance states that at the guidance level dose  to 20
genetic defects would be produced per 100,000 live births (10 ,to 200
genetic defects per million) in the first generation.  However,  we
must also consider the cumulative genetic defects produced for all
generations as a result of such an exposure.  The fact that  there
already is a significant rate of genetic defects does not make an
additional increment more acceptable.

     Staff Response - The rationale for the guidance  is  based on the
staff's technical evaluations.  The numerical estimates  of  lifetime
risk represent best judgments with aJ stated range of  estimated
uncertainty.  Additional risks resulting from transiocation  to other
organs, including bone, were included in the  total risk  to  an
individual.  First generation and  subsequent  generation  genetic  risks
for continuing exposure of both parents at  the  guidance  limits are
given  in  the  technical documents.  The  staff  does not believe  that  .
risk estimates have been underestimated.

     The  guidance rationale considered  serious  genetic  effects  as
expressed within  ten generations  from the  individual  exposure;  all  of
the additional  future  generations  do  not add  significant numbers
serious genetic  effects  in comparison.  The agency has  not  and  cannot
make a judgment  with respect  to  an "acceptable"  rate  of  serious
genetic effects  that would be committed by  the  guidance
recommendations.
                                    17

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 10.  Jefferson County Health Department

      It seems quite likely that releases of radioactive materials  from.-
 the plant have already made some measurable impact on the health of
 populations so exposed.  An examination of death certificates of
 residents dying in 1975 in eight census tracts in south end of the
 county, showed a significant increase in deaths from leukemia in the
 areas near the plant site.  In addition, examination of death
 certificates shows an increase in age-specific death rates from lung
 cancer.  Estimates of risk to health have been published in the
 Proceedings of the IVth International Congress of the International
 Radiation Protection Association.

      Staff Response - The agency staff does not believe that
 epidemiological studies have shown an increase in risk to individuals
 living in the vicinity of the Rocky Flats Plant.  See comment 11 in
 Section 3.3

 11.   Jefferson County Health Department

      I am puzzled that the risk of the proposed guidance level (page
 15)  was less than one chance per million per year,  and less than ten
 per  hundred thousand per lifetime.   Why not be consistent and say,
 "less than one chance per million per year and less  than one hundred
 per  million in a lifetime?"  It is  obvious that these risk estimates
 are  not precise,  and for that reason I would prefer  to see a range of
 risk estimates given as  has been customary in the literature.

      Staff Response - The lifetime  risk of death by  specific cause for
 members of a cohort is  generally given in numbers per hundred
 thousand.   The annual risk for  an individual  can be  given in any
 desired unit — number  per million  was chosen to  avoid values  less
 than one.   An estimate  of the  range of uncertainty is provided.

 12.   Nuclear Safety Associates                                  .

         It  is recommended that the  EPA examine  the  regulations  and
 practices  of other  Federal Agencies  to determine  permitted  levels of
 public  health  risk  associated with  carcinogens and other  hazardous
 substances  the other  agencies  regulate.  The  findings  should be
 considered  in  the interpretation  of  dose  limits associated with
 transuranium elements in  the environment.
     I                     ...                          -..  ^ . •.,
     It  is .recommended that regulatory limits  which  the Agency may  .,.
 develop  for  transuranium  in the environment be consistent in
 associated public risks with regulatory limits for other      -
 non-radioactive substances in the environment  that the Agency          '..,
 regulates.

     The supporting document does not  reflect  the broad perspective
needed to promote consistency and reduce the misapplication of
resources.
                                    18

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     Staff Response— The Agency recognises that -consistency in
regulatory actions based on a limiting risk to  individuals  or
population groups-is both desirable and necessary.  However,  the
societal judgment on level of acceptable risk for  the many  known
and/or suspected carcinogens differs greatly and is based largely on
the perceived balancing of costs and benefits for  each material-or
situation.  The decision-making process must recognize these
differences.  Therefore, consistency in-regulatory actions  does not
necessarily require same numerical risk limit for  each 'carcinogen, but
rather a consideration-of the level of risk acceptable to society.

13.  Department of Energy

     It would ^be help'ful if the terms "risk level" and "cancer risk"
were clarified.  Cancer risk could refer to (a) contracting a cancer
of any kind,- (b) dying of cancer, or :(:c) something else.   (p-16)

     Staff Response - All of the numerical risk estimates are for
cancer mortality.  The difference, between mortality,'and  cancer,
incidence is not  significant for the cancers considered.
                           •--•-'       '   .     * -•      5 "   " .  • •
14.-• Department of Energy                       i:

    -Justification of  the risk level chosen is  not adequate and
provides no convincing comparisons with other risks of  life,       '
particularly those risks which involve 'a comparatively  few  people.:
The examples o£ saccharin and kepone seem  inappropriate  because a much
larger population is involved.   (p-16)

     Staff Response - As evidenced by the  comments received ;-by the
Agency, it  is probably impossible  to choose'-a  single'level  of risk, or
to provide a justification  for a  chosen level,  which  is  acceptable to
all persons  in a  given population.   Such decisions represent a social*
judgment  and cannot be made solely by a regulatory agency.   The
principal rationale for  the guidance value.Is "-that adequate protection
be provided  to individuals  in a  critical segment  of  the population and
that all  other persons be at a smaller  risk.   Comparisons with other
risks  to  life, while not exactly  equivalent,  are  the  best available.
See also  response to comment, 12.         '         ....

15.  Department of Defense

     Risk Perspectives:  This  entire section  takes liberties with  the
true  situation.-   The'estimation  of, risk is based  on data obtained  at
high  dose rates  extrapolated to  low-levels-conditions  and has many ;
assumptions.  This should be stated  initially-and then followed with
what EPA  has determined- to  be "the risk.- The  succeeding aiinex can  go '
into  detail,   (p-24)                                           "  .  "

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      Staff Response - The views of the staff with respect to the
 linear,  non-threshold hypothesis of risk from radiation are analogous
 to those of the National Committee on Radiological Protection and
 Measurements (NCRP) and of the International Commission on Radiation
 Protection (ICRP).

 16.   Department of  Energy

      The limits specified seem excessively conservative, in
 particular, the limit for lung.  If 25 mrem per year is acceptable for
 critical populations exposed to releases from uranium fuel cycle
 facilities (40 CFR  190), it does not seem reasonable to restrict lung
 exposure from environmental transuranics to 10 mrem (1 mrad).   In
 fact,  an exposure limit considerably higher than the 40 CFR 190 limit
 would seem reasonable in view of the lesser probability of exposure to
 transuranics,  and the smaller populations likely to be so exposed.
 (p-21, lines 3-4)

      Staff Response - The intent of the Agency is to reduce all
 radiation exposures to levels as low as practicable.  For the  uranium
 fuel  cycle standard,  this was done by considering the cost of  reducing
 risks.   For the proposed plutonium guidance,  the limit is based on an
 Agency judgment with respect to what would be an unacceptable  level of
 risk  to  an individual.   It is not appropriate to compare standards or
 guides based on such different rationales.

 17.  Department of  Energy

     This  section should be prefaced by a statement emphasizing the
 highly uncertain, and probably maximizing,  assumptions involved in
 extrapolating  radiation risk estimates derived from data obtained at
 high dose  levels  to  the very low dose levels  considered in this
 guidance.   This  point is  now made very inconspicuously in a phrase
 attached  to  an  unrelated sentence near the  end of this section  (p.  27,
 line 23).

     Staff Response - We agree that  there is  an uncertainty associated
with risk assumptions,  but  do  not agree that  the assumptions
necessarily maximize  the  estimated risk

 18.  Department of Energy

     This description of  risk  applies  to  very insoluble 239puQ2
 and not,  as  stated,   to  transuranics  generally,   (p-25,  lines 4-16)

     Staff Response - The risks  are  related to  dose  rates  for the
specified organs and  are  applicable  to  all alpha emitting
radionuclides.
                                    20

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                                    10
 19.   Ilene Younghein

      Comparing death rates  from plutonium to those from chicken pox,
 snake bites  and saccharin is pure hype.   Society is not necessarily
 locked into  chicken  pox or  saccharin or  rattlesnakes for thousands of
 years hence.   The  risks from saccharin could stop tomorrow,  but with
 the  terribly toxic transuranics,  there is no way of stopping its
 deadly emissions.  The  same particle of  plutonium that might kill me
 could also kill another poor soul in the year 2978.

      Staff Response  - The data were  provided to give some
 understanding of the comparative  risks involved in terms of  present
 day  human  diseases and  activities.

 20.   Ilene Younghein

      The proposed  standards of 1  millirad to lung tissue and 3
millirad to  bone seem high  to  me  in  light of the persistent  nature of
 the  transuranics in  the environment-especially plutonium 239.'

      Staff Response  - The comment on the proposed risk level is
 acknowledged.

 21.   Ilene Younghein

      Transuranic elements accumulate in  the  environment from falloutj
 accidents, and  releases  from nuclear facilities.   I find Table A 1-3
worrisome.  Cumulative  deposits went from 0  (uCi/rn^)  in the  early
40s  to  0.00007  (uCi/m2)  in  1954 and  built up to almost 0.003
microcuries per  square meter of plutonium 239  in N.Y.  City in 1975.
It seems that every  time it  rains it rains radiation  from heaven.
Whether that  radiation  comes from Russian or Chinese  or Indian or  our
bomb  testing, or our  abortive  satellite  that broke up  over the Indian
Ocean  and  released over  two  pounds of  Pu-238 to the atmosphere,  or the
recent  Soviet mishaps that  sent their  satellite down  in Canada,
spewing debris  and eventually  fallout.   Add  to  that the fires  arid
releases from Rocky Flats,  the leaks of  Pu at Mound Labs and Hariford,
the buildup of plutonium along the coast  near  the Windscale  Plant  in
England and the  leaking  drums  off  the  coast  of  San Francisco,  the
contaminated  islands  of  the  South Pacific, the  accidents and material
unaccounted for  at Apollo and  at  Crescent and you have a sobering
picture, indeed.  How can we safety  handle increasing  amounts  of  the
transuranium elements when we have done  such a  miserable job so  far?

     Staff Response - The question is  philosophical and beyond the
scope of the guidance.  The  intent of  the guidance  is  to assure
protection of public health  from  existing and future  transuranium
element contamination.

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                                    11
22.  Ilene Younghein

     Your charts  on the  death rates  from plutonium are  not as clear as
the one you  did on Background Radiation on page 9.   You have divided
your statistics between  Pu-239,  and  transuranium elements, lung,  liver
and bone cancer,  inhaled and  ingested  plutonium,  so it  is  hard,  if  not
impossible to  compare  the statistics on plutonium and the  transuranics
of the 1 millirad to lungs  arid 3 millrad to bone,  with  your charts  on
background radiation.  What is the expected death rate  from all  causes
on the inhalation and  ingestion  of transuranium elements per 100,000
people at the  dose allowable  by  your proposed  standards.  If the
environment  becomes contaminated to  your allowable levels, how many
deaths do you  project  over  the radioactive life of these
elements-about 250,000 years  for Pu  239?  With the projected increase
in nuclear plants, breeder  reactors, reprocessing,  and  the
proliferation  of  nuclear power and weapons worldwide, the  levels  of .
plutonium in the  environment  will be increasing steadily.   Allowable
releases may be small, but  the e'ffects  of accidents or  raising levels
of contamination  cannot  be  dismissed.

     Staff Response -  The consequences  considered  in risk  evaluations
for the guidance  include all  types of  cancer or incidence  of serious
genetic defects.  The  risk  levels as stated are for lifetime exposure
of an individual  at the  maximum  dose rate.   It is  deemed very, unlikely
that the entire country  could become contaminated  to the guidance
limits, and  it is not  possible to project cumulative population
impacts over 250,000 years  because of  the very considerable
uncertainties  involved.   Evidence to date indicates that the plutonium
deposited on the  soil  sufaces becomes  less  available for uptake by  man
with time.   Long-term  projections in terms  of  geological time scales
are inappropriate and  of little  use.

23.  Ilene Younghein

     According to the  Tri-State  radiation study conducted  at the
Roswell Cancer Institute in Buffalo, N.Y.,  radiation can cause health
effects other  than cancers, such as  asthma,  allergies and  other health
problems.  There may be  risks  from plutonium in other categories  than
genetic and  carcinogens.

     Staff Response -  The results quoted  are largely speculative  and
not supported by  adequate analyses.  The  risks  discussed in the
technical summary documents are  those  for  which a reasonable
correlation  can be established.

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                                    12
 24.  Ilene Younghein

     The.statement  in section  3.2  p.27  "therefore,  the calculated
 risks may be overstated,  and no  deaths  from exposure to transuranium
 elements  in the  environment have been identified" is irresponsible.  .
 Edward Gleason,  a trucker, died  after his  arm became contaminated with
 plutoriium spilleii from a  container.   Workers at Harford and Rocky
 Flats show5a higher than  normal  incidence  of cancer and leukemia.
 Cancer rates in  this  country have  been  climbing at  a rate of 2.2% a
 year.  Could not a percentage  of these  cancers be due to the buildup  .
 of plutonium in  our air,  soil  and  water?   (p-27)               '  .

     Staff Response - The statement in  Section 3.2  refers only to
 risks to  the.general  population  from  existing contamination levels,
 makes no  reference  to occupational exposures,  and is believed to  be an
 accurate  evaluation of the situation  as of today.   If the linear
 non-threshold hypothesis  of radiation damage were carried to the
 extremely low levels  resulting from worldwide fallout,  one to two
 additional deaths per year on  a  statistical basis would be predicted
 for the entire U.S. population from this cause.   Such small variations
 cannot be detected or verified,  and would  represent an infinitesimally
 small fraction of ail cancer deaths.

 25.  Nuclear Safety Associates

     Interpretation of the maximally  acceptable, risk imposed on a
member of the public  is essential  to  the selection  of dose limits
 stated' in the proposed guidance.   Yet the  supporting document,  EPA.
 520/4-77-16, reflects superficial  consideration of  risjt acceptability
 and therefore inadequate  support for  the proposed dose limits.  For
 example,  the only comparison with  other EPA guidance was a mention of
 the cancer risk  associated with  the action level for kepone in fish
 (no mention of non-carcinogenic  effects on health).   The only
 comparison with  another Federal  agency  was an  FDA risk estimate for
 saccharin consumption and a definition  of  a lifetime risk of one  per
million as "virtually safe."   Only a  few of the  risks of death
 experienced in the US population as a result of  other causes were
 presented for comparison  with  the  risks associated  with the chosen
 dose rate limits for  TRU; by comparison, the estimated  risk associated
with the  dose rate limits for  TRU  is  low.   It  is  thus evident that
 support for the  selection of a maximum  acceptable risk  to a member of
 the public was inadequate, or, at  least, inadequately documented *  It
 is recommended that firm bases interpreting the maximum acceptable
 risk be developed before  corresponding  dose limits  are  selected.

     In view of  the relevance  which the EPA purported to attach to
uniformity and overall perspective in the  determination of a maximum
 acceptable risk  to a member of the public,  it  seems  reasonable  to
request that EPA demonstrate adherence  to  that  philosophy in this
proceeding.

     Staff Response -See  response  to  comment  14.

                                      £3

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                                    13
26.  Colorado Environmental Health Association

     Johnson (1977) in a paper presented  to  the Annual American Public
Health Association has reported increased leukemia  death  rates in  the
eight census tracts nearest Rocky Flats as compared to nineteen census
tracts located in southern Jefferson County.  These death rates range
from 2 to 3 times the rates from southern Jefferson County.  The
census tracts nearest Rocky Flats range from 3 to 33 mCi/km2 or
0.003 to 0.033 uCi/m2 in plutonium contamination of the soil.  The
proposed guideline of 0.2 uCi/m2 is from  6 to 66 times the level
associated with increased leukemia rates  according  to the study.

     Staff Response - The agency has not  accepted Dr. Johnson's report
as a valid epidemiological study.  See response to  comments 10 and  11
in Section 3.3

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 2-3  Economic Cost Associated with  the Guidance
 1.   Department of Defense

      Is $500 the cost for estimating the cost  to do restorative
 actions or is it the cost for doing restoration as implied  in Annex VI?
 (p-17, line 17)

      Staff Response - $500 is stated as the minimum cost for remedial
 actions,  (see also response to comment 4).

 2.  Department of Defense

      There is no basis for concluding that costs of implementing the
 guidance  at the reference level would be reasonable and achievable,
 particularly in view of proceeding discussion concerning the fact that
 costs vary "by location,  contamination level, and other factors" and
 ^...that  there are large  uncertainties associated with both the areas
 involved  and in the estimates of costs."  This whole presentation is
 subjective if not  speculative and in a document of this type,
 objectivity and specificity should prevail.  (p-18, line 7)

      Staff Response - The costs  of implementing the guidance have been
 reviewed  and are disscussed in Section 4.  (see also response to
 comment 6).

 3.    Department  of Energy

      It is  not  clear  what "changes by  factor  of ten"  refers to;
 certainly  not  to the  precision of the  calculations, which  seems  to  be
 implied.   Some  of  the  factors  involved  in  the  calculation  of cost
 estimates may be uncertainly  a  factor  of  ten,  but  the  cost estimates
 should be much  better  than  the basis on  which  the Guidance  itself is
 established.  This  should be clarified.  (p-17,  lines  10-12)

      Staff Response - The statement refers  to  soil  contamination
 levels.  We  do not  understand  the meaning of  the comment "cost
 estimates should be much  better  than the basis  on which  the  Guidance
 itself is established."

 4.    Department  of Energy

     This sentence is not clear.   It reads  as  if $500 per acre is the
 cost of just estimating costs associated with  remedial action.  This
might very well be true,  but is not the meaning intended.  A total
 cost  for remedial action  of $500  per acre is such an unrealistically
 low estimate as  to be grossly misleading.   It includes only  the
                                    25

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monetary costs of the simplest cleanup options, with  no  consideration
of environmental costs, societal  costs or  cleanup  risks.   Certainly  it
cannot be reasonably assumed that a  "minimum  cost" will  be applicable
to all (or even any) areas which  might require  cleanup.
(p-17, line  17-19)

     Staff Response - The purpose of introducing a minimum cost
estimate of  $500 per acre appears to be misunderstood in this
comment.  The  intent of the staff was to  show that, even for such  an
unrealistically low unit cost, the total  costs  of  implementation would'
very rapidly become prohibitively large if the  guidance
recommendations were further lowered below the  proposed  values.  This
conclusion is  based on estimates  of  areas  which exceed certain soil
contamination  levels relative  to  the soil  "screening  level" for  the
proposed guidance  (see Table 2.1).  Actual costs of remedial actions
are likely to  exceed such a minimum  value  and will be substantially
greater in most instances.  Societal and  environmental costs,  while
ordinarily not quantifiable in monetary terms,  would  further add to
the total costs.

5.   Department of Energy

     For a given area, cleanup costs are  apt  to be largely fixed
costs, which will not "necessarily increase as  the difference  between
the existing contamination  levels and those sought becomes greater."
(p-17,  lines 21-23)

     Staff Response - The  costs  of remedial actions  are  necessarily
speculative  and will need  to be  determined on a site-specific  basis.
The stated minimum cost  probably consists primarily of fixed costs,
which become a progressively  smaller fraction of  the  total cost as the
scope and magnitude  of  remedial  actions  increases.

6.   Department of Energy

     How can it be "concluded  that the  costs...would  be  reasonable and
achievable," when  it  is  acknowledged in  the previous  sentence  that
"large  uncertainties  (are)  involved?" Actually,  the  estimated costs
are too low  by a  factor  of 3  as  compared  to DOE estimates for  the same
treatment, and by  at  least  an  order of magnitude  for  any treatment
consistent with the  Guidance.   Furthermore, the costs considered were
only monetary  costs.   No consideration is given to environmental costs
or the  potential  risks  involved in cleanup and disposal.  Also, the
consideration  of  costs  has been limited  to sites  of existing
contamination, although the Guidance is  also applicable  to future
contamination.  Consideration should be given to the probable  costs
associated with possible future accidents,  (p-18)

      Staff Response -  The  conclusion that the costs of implementing

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the guidance for existing  sites would be  "reasonable and achievable"
is based on an evaluation  of  the data on .environmental  contamination
levels for these sites, which indicate  that  the  sizes of areas which
may require remedial actions  at the  proposed guidance levels are, all
relatively small.  Therefore, regardless  of  the  cost of remedial
actions per unit area, the  total costs  are expected  to  be consistent
with the objectives of the  guidance.                             '.

     Consideration of environmental  costs and of potential risks, is an
integral part of the decision making process, and must  be addressed in
implementation of the guidance recommendations.   Alternative actions,,
such as restricted occupancy  or use  of  lands, are available where soil-
disturbance or removal are  either  impracticable  or detrimental, on a
long-term basis.  The staff believes that the flexibility of,the means
for implementation offered  by ,.the  Federal Radiation  .Guidance   r:
procedures, and the common  sense of  local and Federal officials, would
make it possible to minimize  the social and  environmental costs
effectively.                                             •  -

     A more detailed discussion of costs  as  applied  to  remedial
actions at both existing and  future  sites of contamination is  given in
Section 4.

7.   Department of Energy                      ,           -.,••    ••.--•

     These numerical estimates of  cleanup costs,  by  employing an  '   :
unrealistic figure of $500/acre, and by ignoring environmental costs,
lead the reader to the erroneous conclusion  that great  benefits can be
obtained in the vicinity of Rocky  Flats by the expenditure of  only • ,
$100K or $500K.  Even with  more realistic cost estimates., this table
seems inappropriate for the Summary  Report because of the^extensive
further discussion required for its  proper consideration.          ,  ,

     "Less than" signs are  not used  consistently. If areas are "less
than," corresponding costs  should  also  be "less  than."   Actually,  a
"less than" value in a table  such  as this has little meaning since the
reader has no idea of "how  much less than."         ;     ,           ,

     It does not appear reasonable that a decrease in reference level
by a factor of 3 would increase the  area  involved from1 zero to • -•:••••.
80 nu.2 at the Nevada Test  Site or  from  zero  to 20 mi^ at Trinity
Site.  This implies a degree  of uniformity in contamination level, that
is difficult to believe.   (p-19, Table  2.1)                     .

     Staff^Response - The  comment  implies that.EPA considers a  • .
reduction by a factor of three or  ten below  the. Guidance       ,   	,..
recommendation as conferring  a "great benefit."   This is not correct,
and the costs of such further lowering  of the recommended dose limits
would have.to be balanced  against  the very small additional gain .in

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public health protection.  Even  if  it were  assumed  that  the  cost  of
remedial actions was as  low  as $500/acre, a further reduction  is  not
warranted for the Rocky  Flats Plant  and  the cost  of averting one
additional  fatality would be at  least several million  dollars.

     Areas  of contamination  represent best  estimates.  Data  were
derived from published contour maps  prepared by the Department  of
Energy or its predecessors.  Uniformity  of  contamination within
contour intervals must be assumed in the absence  of more definitive
information.

8.  Department of Energy

     To the extent that  costs of implementing the Guidance were
considered  in arriving at an acceptable  level of  risk, this  level has
most certainly been biased in the direction of an unjustifiable
smaller risk.  This is because the estimate of cost employed, $500 per
acre, is an unreasonable monetary estimate  low by a factor of 3 as
compared to DOE estimates for the same treatment, and  by at  least an
order of magnitude for any treatment consistent with the Guidance),
and because it includes  no consideration of non-monetary societal and
environmental costs.

     Staff Response - The costs  of $500  per acre was assumed to be a
minimum cost.  It was intended to be used to demonstrate that,  even if
costs of remedial action were this low,  the costs of proposing  a  dose
limit that established a soil limit  below 0.2 uCi/m^ would be
prohibitive.  The $500 per acre  cost was not used to establish  an
acceptable  level of risk.

9.  Department of Energy

     One of the "two primary criteria used  in determining the guidance
recommendations..." was  "...that implementation of  the guidance be
feasible in terms of overall economic impacts."   (Summary Report,
p. 14).  It is further noted  on p.30  that "Monetary  costs,
environmental costs, and other non-monetary costs should all be
considered in the evaluation of  each alternative combination of
possible remedial actions".  From these  statements  one might
anticipate that a considerable portion of the justification  and
explanation of the Guidance  would consist of detailed  analyses  of the
costs of required remedial actions.  Such,  however,  is not the  case.
Two pages of generalities are devoted to "Costs of  Remedial Actions"
in Annex 5, and a single page plus table are devoted to  the  same
subject in Annex VI.  No references are  given to any methods or
sources employed in arriving at  costs, and  the only number actually
used in the estimation of remedial costs is  $500 per acre.  Yet,
assurance is given, on p.18  of the Summary  Report,  that  "It  can be
concluded that the costs of  implementing the guidance at the reference
level would be reasonable and achievable".   No justification is
provided for this critical conclusion.
                                     28

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       The $500 per acre figure employed for estimating "costs of
  remedial actions  at various sites of existing plutonium contamination"
  appears  to include $250 for radiological surveillance, $200 for dust
  stabilization and $20  for revegetation,  rounded to $500/acre.  These
  are  unreasonable  estimates for even the  most minimal required action.
  They ignore the recommendations of Annex V on implementation, since
  estimates  of contamination are based on  existing data, obtained in a
  manner very different  from that recommended by EPA,  with few, if any,
  particle size analyses,  and certainly no demonstration that the
  statistical probability of being in error is no more than 5-10%.
  These estimates,  as applied to sites of  existing plutonium
  contamination, are grossly misleading in terms of costs  already
.  incurred at these sites.

      Of  greater concern  than  these sites of existing plutonium
  contamination, are the  costs  that  might  be  associated with future
  incidents  of contamination.   The  possibility of such incidents should
  have been  recognized and  the  costs  estimated,  including  not only the
  monetary costs of actual  cleanup  and restoration,  but the possibly
  greater  costs of  population evacuation or monitoring,  of environmental
  impact assessment,  of decontaminating homes,  roads,  or commercial
  areas, of  income  loss from cessation of  agricultural  or  commercial
  activities,  of demonstrating  eventual compliance with the
  Guidance—and also  including  the environmental  and non-monetary
  societal costs incurred, not  neglecting  the  health risks  of the
  cleanup operation.  Any such  total  and realistic consideration of
  costs might well have led  to  a  different  conclusion  concerning their
  "reasonableness and achievability"; which might, in  turn,  have
  influenced  the choice of Guidance recommendations.

      Staff Response - The  $500 per  acre was not determined  from
 estimated costs figures.   It was intended to demonstrate  that even  if
 costs of remedial  action were that  low, the costs of proposing a dose
 limit that established a soil limit below 0.2 uCi/m2 would be
 prohibitive.

      An estimated  cost of remedial action of $500 per acre is
 undoubtedly low.   However, it is a misconception to consider the cost
 of acquiring data  on the concentration of transuranium elements in the
 soil  to  be  a cost  of remedial action.  These costs would be incurred
 in any case, no matter the guide level established and would,
 presumably, be incurred even if there were no guide.   The costs of
 acquiring data to  determine if remedial action is required is better
 considered  to be a cost of the incident of contamination than a cost
 of clean-up and restoration.

      An  important  consideration in estimating the costs of future
 incidents of contamination is  the probability of their occurance.
This  has  been ignored by DOE.   Actually,  a set of probabilities is

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needed for covering a number of situations,  so  that  the  expected value
(expected costs) of failure incidents can be  determined.  The  set  of
probabilities should include not only the probability  of the occurance
of incidences of contamination, but also probabilistic expressions of
the sizes of the expected incidences and the  types of  lands impacted
(e.g., agricultural lands, forests, urban or  industrialized areas.)
DOE's discussion seems to assume that the probability  of a future
incident is one for the cases where costs are analyzed and zero for
the cases where costs are not analyzed.

10.  Department of Defense

      The summary report states that "...generic  guidance applicable
to all sites cannot be provided by formal cost-benefit procedures".
It also states that "The primary criteria used  in determing the
guidance...(is) that implementation of the guidance  be feasible in
terms of overall economic impact".  The substance of the  guidance  is
generic, regardless of what clean-up level is eventually determined
because the guidance is stated in terms of a  limiting  dose which is
the same for any site.  This example is used  to illustrate the
inconsistency and ambiguity within the document as well  as to question
what was the basis for providing the generic  guidance when one hand is
saying economics prevented it and the other hand  is  saying economics
was the primary criteria.

     Staff Response - The objective of the recommendations is  to
establish a generic guide which is adequately protective  of the public
health.  Formal benefit-cost procedures were  not  used  in the
derivation of the guidance recommendations because they  do not lead to
a generic guide; they would require that an  independently determined
level be established for each site.

     Economic analyses were limited to a determination that costs  of
implementation for both existing and possible future sites are
reasonable.

11. Nuclear Regulatory Commission

     It appears that the costs of taking remedial action for
facilities licensed by this Agency would substantially exceed  the
lower limit value of $500 per acre assumed for  the proposed guidance.
For example, disposal of surface soils by burial  in  commercial
low-level waste burial sites would probably equal or exceed the costs
of the general per cubic foot charge for burial.  Using  a value of $3
per cubic foot (NUREG-0217), would result in  an estimated cost of
$5000 per acre for burial charges alone.  Using a value  of $3 per
cubic foot (NUREG-0217), would result in an estimated  cost of $5000
per acre for burial charges alone.

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                                   7
         Staff Response - We agree.  While costs of remedial action
may vary greatly, depending on level of contamination, location, land
use and ecological factors, etc., the costs of remedial actions can
generally be expected to be greater than $500 per acre.  This is
especially true in cases where long-term storage or burial is
required.  The assumed least cost value was used solely for purposes
of setting a lower limit on the numerical limits, and does not
represent an analysis of costs for cleanup.and restoration at existing
or possible future sites of environmental transuranium element
contamination.
                                  .31

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2.4  Imp1ementa ti on
1.    Colorado Department of Health

     The guidance document contains air concentrations  and  surface
soil levels which are related to the numerical dose  rate  guidance.
These air and soil values should be inserted  in  the  text  of the  actual
guidance with qualifying statements as to  their  appropriate use  in  the
implementation of the guidance.

     Staff Response - The guidance is stated  in  terms of  dose  rate
limits to specific body organs.  Derived air  or  soil "screening
levels" are intended to assist  in implementing the guidance in a
cost-effective manner, and do not constitute  the guidance.   It would
therefore be inappropriate and  misleading  to  include, these  in  the  text
of the guidance.

2.   Department of Energy

     Derived Limits for Air and Soil:  The restrictive  nature  of the
basic radiation dose limits is, of course, reflected in the derived
limits for air and soil.  Their derivation also  introduces  additional
conservatism, which can be only partly justified in  terms of their
intended use as screening levels below which  no  action  need be taken.
The derived soil limit is featured in the  Summary Report  as a
"screening level" and its utility in facilitating economical
implementation of the Guidance  is appropriately  emphasized  (p. 29).
The derived air limit, however, is not found  until Annex  V  (p. 6),  and
its use is recommended only as  a last resort  when other approaches  are
"difficult or impossible."  It  is not clear why  the  derived air  limit
cannot provide a screening level that is more useful than the  derived
soil limit, since the air limit is more directly related  to inhalation
hazard than is the soil limit.  While it can  be  argued  that an air
screening level would ignore  the ingestion route, the  same  argument
applies to the soil screening level as it  is  presently  derived.

     Air Screening Level;  It is recommended  that an air  screening
level be identified as such,  and given greater prominence in the
Guidance.  The level of 1 fCi/m3 defined in Annex V, based  on  an
unrealistic value of 2.6 fCi/m-*, employed  in  the derivation of the
soil screening level (Annex  11, p. 33) seems  more appropriate.  In
order to account for uncertainties introduced by not considering the
ingestion route, and non-ambient inhalation routes,  it  is suggested
that an "unqualified air screening factor" might be  established  based
on a detailed analysis of the probability  of  significant  contribution
from other-than-routine inhalation exposure.  Any number  derived for
an air screening level should,  of course,  be  increased  proportionate
to any increase in the basic  radiation dose limits.

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     Soil Screening Level;  The relationship between the quantity of  a
radionuclide inhaled, and the quantity of that radionuclide  in  the
soil is a complex one, which can be predicted only with great
uncertainty.  Because of this uncertainty, parameters chosen to
develop such a relationship tend to produce a conservatively biased
result.  The mass loading approach employed in this Guidance has many
faults which are pointed out in the Page-by-Page Commentary, together
with suggestions for improvement.  However, it is not clear  that a
totally different approach would yield a better result.

     In these circumstances, a decision as to how conservative  is
conservative enough becomes rather arbitrary.  However, the  following
list of conservatisms presently included would strongly suggest that
the derivation of the soil screening level is more conservative than
it need be:

     (a)  The assumed mass loading of 100 ug/m^ is 2 to 10 times
higher than shown by .the data of Fig. A 2-2.

     (b)  The assumed percentage of the airborne particles in the
respirable size range, 100%, is 3 to 4 times greater than shown by the
data of Fig. A 2-3.  Such an assumption is especially inappropriate
when used in conjunction with a mass loading of 100 u'g/nr'.
                                       •   ; '      -   O        , •    -     "
     (c)  The allowed air concentration of 2.6 fCi/m-5, based on AMAD
of 1.0, is a factor of 2 smaller than would be allowed if the AMAD of
the respirable fraction were more realistically .assumed to be in the
2-5 um range .

     (d)  The lack of any correction for area size introduces a very
large factor of conservatism, unless extremely large areas are
involved.  As pointed out in Annex II (p. 29), this may be a factor of
100 or more for areas with dimensions Fof the order of 50 meters.  Such
small areas of contamination are likely to be typical of most future
contamination incidents.
                                                   
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 present  soil  screening  level  is  probably sufficient  to accommodate
 such an  ingestion  component,  but it would be  more  convincing to
 estimate the  ingestion  component independently  and add it  to an
 appropriately reduced inhalation component.

      Staff Response - The agency staff  does not  recommend  use of  the
 soil screening level when inhalation  is  the principal  pathway.
 Correlation of soil concentrations with  inhalation doses requires
 calculational models which necessarily  introduce some  uncertainties.
 The potential inhalation hazard  can be more directly related to the
 ambient air concentration.

      Where ingestion is a possible pathway, the soil screening  level
 has greater applicability.  Although not  derived on the basis of
 ingestion, the staff has found use of the  soil screening level  to  be
 sufficiently concervative to  limit exposures  to less than  the Guidance
 dose limits when plutonium is the major constituent of the
 transuranium element contamination.  The  derivation of the soil
 screening level was not based upon the ingestion pathway,  since that
 is extremely site dependent - even more so than the inhalation
 pathway.   Ingestion is not the principal contributor to the  total  risk
 at sites  of existing contamination.  For future accidents, the
 relative  importance of the ingestion pathway is not possible to
 predict.

      The  staff does not  agree with DOE that the soil  screening level
 is more conservative than it  need be for the following reasons:

      a)  A value  of 100  ug/m3 was chosen in order to  cover the
 possibility that  localized resuspension could  also  contribute to the
 inhalation dose.  These  local disturbances would not  be reflected  in
 the average mass  loading for  the  general area.  The value of
 100 ug/nr5 is consistent  with  values used by others  who  also
 attempted to factor local  resuspension into their calculations (see
 Annex II).

     b)   The percentage  of airborne  particles  assumed respirable is
 not 100Z.   The assumption  was  that the  particle  sizes of  suspended
 dust are  distributed lognormally  with  an  AMAD  of  1.0 urn.

     c)   A factor  of 2  is not significant.

     d)   The  size  of the  area contaminated by future accidents  can
not be predicted.

     e)   This would be a  small correction.

f)  Justification for the use  of  the enrichment factor  is contained in
Section 3.2, response to comment  30

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3.  National Council on Radiation Protection an?! Measurements

     The approach taken is to provide dose  limits  for  lung  and  bone.  •
These limits are then to be applied by the  agency  responsible by  a
combination of measurements ;and models involving intake  and retention
since the dose to these organs cannot be measured  directly.
Unfortunately, these models and coefficients are not well developed
and methods of measurement for inhalation of other than  ambient air
are not really available.  This will result in adding  considerable
conservatism to the analysis and in continuing the controversy  over
the safety of a given area.

     We" would recommend that the EPA reconsider this approach in  favor
of setting soil levels that incorporate all known  pathways  of exposure
and considering the necessary conservatism  in these models  along  with
any conservatism incorporated in the risk estimates and  dose
calculations.  While this may provide a limit for  some areas lower
than is needed, it will allow consideration of all factors  of
conservatism and will provide an unequivocal number that can be
accepted by all.  We would also suggest that analyses  of different
areas be made taking into account, even.crudely, all possible pathways
to see if the area difference is as great as assumed.

     Staff Response - The guidance is stated in the most direct units
possible and is intended to provide for the deviations appropriate  to
specific sites.  Use of a single "spil sceening level" would remove
the possible options available without any  compensating  benefit.  The
inclusion of all appropriate factors of conservatism in  a single
numerical value would necessarily require that the most  restrictive
level be applied to all sites, with the consequence of possibly
greatly increased costs of implementation and unnecessary damage  to
the environment.

4.   National Council on Radiation Protection and  Measurements

     One of the concerns is the potential impact of future  accidents
that may release transuranics into the environment. The current
guidance is not clear as to what should be  done.   In discussing the
accident, it is stated.that the material should be cleaned  up"...as
soon as possible..."  However, elsewhere in the document, we find
requirements for detailed assessments are needed for the accident
situation.  We also note that no studies of potential  accidents and
cost of cleanup at this level as opposed to levels somewhat .higher  or.
somewhat lower were done to determine whether the  reduction in  risk  is
worthwhile.  While such costs should be included in the  .cost of the
operation, there is no reason to believe that this justifies
unnecessary costs if not warranted by the risk reduction.
                                    35

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     We  recommend that the actions following a future possible
 accident be better defined and that a study be made to show that these
 limits are  appropriate.

     Staff  Response - It is not possible to predict with any degree of
 confidence  either the probability or consequence of future incidents
 which could release transuranium elements to the environment.  The
 agency staff believes that the proposed criteria for protection of the
 public health are as appropriate for the case of future accidents as
 for existing contamination, and that no valid reason exists for
 establishing different dose or risk levels.  Therefore, the
 recommendations  of the guidance are intended to be viewed as minimum
 performance objectives,  and lower values are to be attained when these
 can be achieved  with reasonable expenditure of resources.  Because the
 number of possible accident scenarios is virtually infinite, no useful
 purpose  would appear to  be served by evaluating the costs of risk
 reduction.   The  range of remedial actions required will depend on the
magnitude of the accident and  on the potential impact on individuals
 and populations.   In most cases,  a rapid response can be expected to
minimize the consequences and  reduce  the overall costs.  The
 interaction of all  these variables would determine the appropriate
 response in each case.

     In  the opinion of the agency staff,  actions following a possible
 future accident  are generally  defined by emergency response criteria
and do not  properly fall within the scope of this guidance.  Planning
for such emergency  response is  the responsibility of the agency under
whose auspices the  pertinent activity is  carried out.   If the
anticipated consequences of any ongoing or projected activity are
likely to exceed  the  guidance  recommendations,  an EIS may be required.

5.   Department  of  Defense

     There  is  confusion  possible  in terms  of the radionuclides  to
which the guidance  applies  because of the  wording.   It appears  the
guidance  covers  all  transuranium  elements,  yet  it is  stated in  terms
of alpha  radiation  doses.   Some transuranium elements  are not alpha
emitters—how  are these  to  be  addressed?

     Staff  Response - The  guidance is  intended  to apply to all
transuranium elements.   Beta emitters  (such  as  plutonium-241)
contribute  little effective dose  and  need  not be considered.  Daughter
products, which generally  are  alpha  emitters, are included in the
calculations.

6.   Commonwealth Edison  Company

     Commonwealth Edison  Company  endorses  the concept  of "screening
levels"  for environmental  contamination below which  costly
                                     36

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environmental surveys need not be undertaken to demonstrate compliance
with the proposed dose rates.o However, we.believe that the derived
value for airborne contamination suggested by the EPA  is too  low  to be
practical, and consequently will not accomplish the purpose for which
it is intended.  Specifically, we know of no way to measure accurately
EPA's derived limit of 1 fCi/m3.  Further, it will not be possible
to separate out ,the contamination resulting from an unplanned release
of transuranics from ambient background contamination  unless
environmental surveys are conducted on a routine basis.

     Staff Response - The detection of contaminants in air  is a
function of the concentration, sampler flow-rate, sampling  duration,
chemical yield of the analytical procedure, and the sensitivity of  the
analytical technique (see Bernhardt, Evaluation of Sample Collection
and Analysis Techniques  for Environmental Plutonium,  in "Selected
Topics: Transuranium Elements in the General Environment",  EPA
Technical Note ORP/CSD-78-1  (1978)).

     The minimum sensitivity for plutonium-239/240 for most
laboratories is generally around 10  to 20 fCi  on  the  final  sample
submitted for nuclear counting.  Assuming a  fairly low yield  of  50
percent  this gives  a minimum detectable  sample  activity of  20 to  40
fCi.  For this example,  this level  is  raised  to  100  fCi per sample, to
insure a  reasonable analysis.  Using the  screening guide  of 1 fCi/m-3
and  a median sampler  flow-rate of  about  0.28 nr/minute
(10  ft3/min),  100  fCi is collected  in 360 minutes, or about six
hours.    For a  long-term average,  such as  is  specified by the EPA
Guidance, sampling  times of several  days  to a  week are used.   Sampling
for  about 3  days, using  the above  parameters,  will result in about
1000 fCi (1  pCi)  of activity on  the  filter  (based on 1 fGi/m3),
which  is well within  the ideal  range for low-level plutonium 239/240
analysis.  An  air concentration  level for  plutonium  of 1  fCi/mJ  is
greater  than current  levels of  plutonium is ground  level  air due to
fallout  and,  therefore,  can be  detected  in the presence  of fallout
plutonium.

7.    Jefferson County Department of Health

      The offsite contaminated  area around the Rocky  Flats plant is
under  my jurisdiction as public health officer for  Jefferson County,
 and I emphatically disagree with the statement in the guidance that
 "all offsite areas probably would be in compliance with the  guidance
 recommendations".  My own survey has shown levels of plutonium in
 surface respirable dust  to be as high as 3,390 times fallout levels.
Although the guidance states "The area is sparsely inhabited, and
 there are few people living in the particular area of concern", please
 be advised that the State Health Department approved this land (with
 3,390 times fallout levels of plutonium) for residental development,
 and this move was blocked only with considerable difficulty.  I

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  estimate that in the area of concern originally established by the
  State Health Department,  that as many as 100,000 persons may be
  settled if the efforts of developers are not restrained.  Much of this
  area  is now under development.

       Table 2.1 on page nineteen compares the cost of remedial actions
  with  existing plutonium contamination as indicated by isopleth maps.
  The areas  noted to require  remedial  action  at Rocky Flats  are too
  small,^in  view of a recent  survey utilizing respirable dust samples.
  There  is significant  contamination outside  the isopleths referred to
  in this  table.

      Staff Response - The Agency  staff  does not  believe  that  guidance
  recommendations  should be evaluated  in  terms  of  multiples  of  fallout
  levels, but rather  in terms  of  risk  to  the  health of people.   The
  staff also  disagrees  with the analytical procedures  proposed  by
 Dr. Johnson   for  surveying plutonium levels in the  environment.   The
 areas of disagreement  are discussed  in  Section 7  of  this document.
 The concentration of  plutonium  in  offsite soil is highest  near  the
 site boundary and decreases with distance from the  site.   Therefore
 there is a potential  for only a limited number of persons  to be
 exposed to levels approaching guidance  recommendations when the areas
 surrounding Rocky Flats are developed.  The vast majority would
 potentially be exposed  to much lower levels.  The agency staff
 believes public health protection will be achieved under these
 conditions.

 8.    Ilene  Younghein

     Annex  1 p. 12 "The milk surveillance network around NTS does not
 analyze samples for plutonium."   Why  not?  p.17  "of the approximately
 8 curies onsite, more than half  is believed  to be stabilized by
 coverage with an asphalt pad and remedial measures are being taken to
 control the remainder to the extent practicable."  Is asphalt
 considered  to be a permanent solution to plutonium contamination?  You
 did not define your remedial measures nor what is meant by  extent
 practicable.   What is  really being said-that the  measures taken are
 temporary-that to really remove  the contamination would be  extremely
 expensive and  probably impossible.

     Staff  Response  -  (a) Plutonium does not accumulate in  milk and
 cannot be detected  (b)  The Agency  has not provided  a judgment  on the
 adequacy of remedial actions.  The  statement is a report  on an
 existing situation.

 9-   N.Y. Federation for Safe Energy

     The guidance  speaks of clean up.  How does one  clean up water,
and where does one take  soil  that needs  scraping?
                                     38

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     Staff Response - Transuranium elements are generally very
insoluble in water and are associated primarily with sediments.
Restrictions on use of drinking water supplies may need to be imposed
if dose rates to individuals at a specific location approach the
guidance recommendations.

     Contaminated soils may be stored in designated repositories.  A
number of commercial-facilities have been licenced by the States and
the Federal government operates several high-level waste storage
repositories.

10-  Colorado Environmental Health Association

     If the proposed guidance of 0.2 uCi/m^ is affirmed by EPA and
the scientific community, we recommend that all land areas with soil
contamination exceeding the guideline be mitigated as described under
"Remedial Actions and Economic Evaluation".  Applying the 0.2 uCi/m^
guideline to the attached figure of soil contamination would require
that any area exceeding 30 dpm/g would require mitigation.
Approximately 1 square mile outside the Rocky Flats boundary and about
1.5 square miles inside the boundary exceed the guideline.

     Staff Response - The guidance recommendations are in terms of
dose rate limits to individuals in a critical segment of the
population, and not in terms of a soil contamination level.  The scope
of remedial actions which may be required to achieve compliance must
be determined on a site-specific basis.  The guidance is applicable
only to those areas outside the limits of Federal  facilities.

11.  Colorado Environmental Health Association

     Although the guideline fails to recommend a specific sampling
technique, it appears that the respirable dust technique .offers the
most practical method of estimating exposures to human populations
since dust-borne plutonium may be inhaled and is thought to cause lung
carcinomas and leukemia.

     Staff Response - We do not agree.  Soil sampling and analysis.
methods represent a secondary means of assessing health impacts and of
implementing the guidance.  The superiority of the "respirable dust
technique" has not been demonstrated (see Section  7).

*^•  Colorado Environmental Health Association

     We feel that the discussion of soil contamination in the
environmental impact statement has not thoroughly  addressed the
controversy pertaining to the amount of radioactivity in the soil.  If
the scientific community finds the EPA proposed Guidelines  for
Transuranium Elements in the Environment to be appropriate, then the
standard should be applied to Rocky Flats and discussed in  the Final
EIS.

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      Staff Response - The guidance is not intended as an
 implementation manual and therefore does not discuss the merits of
 different soil sampling and analysis methods.  Application to specific
 situations is the responsibility of Federal agencies having site
 juridiction.  Preparation of an Environmental Impact Statement is
 required only for major Federal actions.

 13.   Department of Defense

      This sentence is a non sequitur.  It does not follow that just
 because all sources of transuranium elements are under direct control
 of the  Federal Government that Federal guides are an adequate means to
 limit any problems of environmental contamination by the transuranium
 elements.

      Staff Response - The Agency believes that Federal Radiation
 Guidance is both an adequate and equitable means of providing
 protection of the public health by establishing uniform dose rate
 limits  for exposures due to environmental contamination by
 transuranium elements,  while maintaining the flexibility of
 implementation not generally afforded by standards.

 14.   Department of Defense

      This is typical example of use of non-specific,  non-meaningful
 words and phrases.   The term "as soon as possible" has little stature
 in a  regulatory or compliance  sense.   A definite time should be
 specified,   (p-18)

      Staff Response - The  Guidance  contains  recommendations  which are
 intended to have  a certain degree  of  flexibility.   The indeterminate
 nature  of the  type,  magnitude,  and  location  of future incidents  of
 contamination makes  it  both  inappropriate and impossible to  give
 specific directions  for remedial actions.  The objective of  remedial
 actions  must be  to minimize  both the  immediate and long-range risk to
 exposed  persons.   It  is  the  responsibility of the  agencies charged
with  implementation  of  the Guidance  to develop an  adequate and timely
 response in each  instance.

 15.   Department of Energy

      Some  recognition should be  given  to  the  fact  that  "as soon as
possible  after occurrence" could be a  long time  because  of the
complexities of establishing the extent  and  location  of  contamination
and the  cost benefit  analysis required before  remedial measures are
taken—not  to mention the  possible requirements  for an  environmental
 impact assessment.  The  idea that there might  be a  desirable
compromise  between immediate, thoughtless  recourse  to  bulldozers,  and
a 5-year  study of environmental  impact,  should  somewhere  find
expression  in this Guidance,  (p-18, line  25)

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                                    10
     Staff Response - It was deemed appropriate  to allow  flexibility
in implementation procedures and schedules.   It  is expected  that
common sense judgments, designed to minimize  the  health risks  of
individuals and the population, will be made  by  designated officials.

     However, the agency staff wishes  to emphasize that analyses
indicates that, when a contaminating event occurs, most of the
radiation dose associated with the event is committed within a short
time (within a few months) unless protective  measures are taken.  This
is because the resuspension factor for newly  deposited material is
much higher before weathering and movement into  soil surfaces  occurs.

     Should a potential contamination event occur, the responsible
Federal agency should take immediate remedial measures to prevent the
airborne movement of the transuranium element.  These measures are
likely to be temporary measures that simply hold  the transuranium
elements in place.  Following such temporary measures, remedial
measures appropriate to a long term solution  should be implemented.

16.  Department of Defense

     For health physics and protection reasons, why not also state the
mi11rad numbers in millirem equivalents.  From a  regulatory
standpoint, millirad is preferred for regardless  of what quality
factor is chosen for alpha, the guidance is the same.  But for
practical purposes, the protection industry works in millirem.
(p-21, lines 3-4)

     Staff Response - The conversion, if necessary or desirable, can
easily be made in implementation manuals.

17.  Department of Defense

     A conclusion that is not supportable appears in the following
paragraph where it is stated that "the control measures are  expected
to result in levels well below those specified in paragraph  one" i.e.,
1 and 3 millirad.  Why would this be expected?  If remedial  action is
done to the degree required .literally, then one would reasonably
expect that the levels would be not more than 1 and 3 millirad, but
certainly not "well below."  This typifies many examples of  the
luxuries the authors have taken throughout the document in making
subjective statements, loose associations and rambling discussions.
(p-21, para. 1)

     Staff Response - In general, it may be expected that, if  remedial
actions are applied to all areas which exceed,the soil "screening
level," this will result in an average environmental contamination
level lower than the "screening level" and result in dose rates to
individuals well below the guidance recommendations.  It is  not

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                                    11
 reasonable to expect that responsible implementation of the Guidance
 recommendations,  where remedial actions are actually required, would
 stop at  the minimum requirement.   Literal interpretation of the
 "screening level" as the absolute lower limit is obviously not in the
 spirit of achieving maximum radiation protection of the general
 population.

 18.   Department of Defense

      Remedial action is  stated as "may be.required at any site that
 fails to meet these criteria." Presumably, since this is a guidance
 that limits the dose to  man because of contamination of transuranium,
 remedial action would be required at any site that fails to meet the
 criteria,   (p-30,  Sec. 3.4)

      Staff Response - Adherence to the guidance recommendations on the
 part of  the responsible  Federal agency is not mandatory, but adequate
 justification must be given for deviation.

 19.   Department of Defense

      The DOE does  not believe  that "all sources of transuranium
 elements are under direct  control of the Federal Government" (e.g.,
 foreign  space satellite  components).   Further it does not follow that
 "Federal Guides...are — an adequate means to  limit any problems of
 environmental contamination,"  especially since all potential sources
 of transuranic  elements  are not under Federal control,  (p-12,  lines
 9-12).

      Staff  Response - The  amounts  of transuranium elements  not  under
 direct control  of  the Federal  Government are  considered minimal and
 unlikely to  cause  significant  problems.   Foreign intrusions,  such  as
 the  reentry  of  a Soviet  space  satellite,  would need to be considered
 on an ad hoc  basis.   Federal intervention is  considered likely  in  the
 event of any  substantial contaminating event  involving transuranium
 elements, irregardless of  ownership.

 20-  Department of  Energy

     Again, unless  "guidance recommendations"  is  understood  to  be
 strictly  limited to  the  radiation  dose limits,  it  is  erroneous  to  say
 that  they represent  a "maximum value."  The wording encourages
misunderstanding,  since  the "screening level"  might well  be  considered
 a "guidance recommendation" but should certainly  not  be considered a
 "maximum value."   (p-20, lines  15-16)

     Staff Response  -  The  comment  indicates a  misinterpretation of the
 statement referred  to.  The recommendations are  to  be  considered as
upper limit values  and the principle  of  "as low  as  reasonably
achievable" is  to be  applied to the extent practicable.
                                   42

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                                    12
 21.   Department of Energy

      This sentence should be referenced to the place in this Guidance
 where "representative measurements" and "reasonable procedures and
 assumptions" are defined,  (p-24,  lines 2-5)

      Staff Response - The discussion of details pertaining to
 implementation procedures is not appropriate in this Guidance.

 22.   Department of Energy

      Although a soil "screening level" is a potentially useful
 concept,  ambiguities concerning how the screening level is to be
 employed,  either technically or administratively, make it of
 questionable practical value.   Annex V offers little help in this
 regard,   (p-29,  lines 11-15)

      Staff Response - The soil  "screening level" is an optional  method
 available  to the implementing agency,  which we believe to be practical
 and useful.   Development  of  detailed technical and administrative
 procedures are the responsibility  of the implementing agency.

 23.   Department  of Energy

      "Remedial action may be required."  It is nowhere quite clear
whether remedial  action is ever required,  or whether radiation dose  in
 excess of  EPA Guidance may be justified in some manner.
 (p-30, lines  7-8)

      Staff Response  - The Guidance  recommendations  should not  be
exceeded unless  deviations are  justified.

24.   Department  of Energy

      The alternative  of "restricted  access,  or use"  is mentioned, but
receives no  further  consideration.   There  are  degrees  of  usage that
might well be  discussed,   (p-30, line  12)

      Staff Response  -  The Guidance document  is  not  intended  to be an
implementation manual.

25.  Jefferson County  Department of Health

      I am concerned with the criteria on page  60957  in the first
paragraph, Rationale  for Guidance.  One of  two  primary critera used in
developing this guidance,  "That any actions  required by implementation
of the guidance be practical in terms of overall^economic
requirements".  In view of the nature of the guidance proposed,  I feel
that economic concerns have really been given  foremost consideration,

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                                   13
perhaps with intent to minimize any economic  impact on  federal
agencies or private corporations which have contaminated  offsite
lands.  It appears to me that the concern  for  the public  health has
been given lower priority here.

     Staff Response - The criteria for establishing the guide level
was that the risk to exposed individuals be acceptable.   This level
was determined with no consideration  for the  costs of remedial
action.  EPA then determined that the costs of performing the required
remedial actions were practical.

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2.5. Biological and Environmental Models

1.   Ilene Younghein

     "A more detailed treatment of the dose  to children  is not  likely
to result in appreciable difference in the risk  since most of a
person's body burden is accumulated during adult life, not
childhood."  This statement is very questionable.   Children's cells
grow and divide faster so radiation damaged  cells  proliferate faster.
Also children carry the damaged cells for longer periods of  time.
Children too would be more penalized by the  life shortening  process  of
radiation than an adult.  It is also possible for  plutonium  to  cross
the placenta, from the mother's blood into the blood of  the  fetus,
where it may kill a cell responsible for development of  part of an
organ, such as heart, brain, liver etc, causing  deformities  to  occur
in the developing fetus.  This mechanism for production  of fetal
deformities is called teratogenesis and is different from the
deformities caused by genetic mutation in the egg or sperm (similar  to
the drug thalidomide).  The discussion on risks  to children  is
incomplete and misleading (Section 3.2 p.5).

     Staff Response - All of the points mentioned in the comment were
considered in the assessment of risk.  Refinements in  the dose  model
for children are unlikely to change the numerical risk estimates to
any appreciable extent.

2.   Ilene Younghein

     Contrary to your statement, it is possible  to get a lifetime  dose
of Pu 241 (half-life 14.8 years) and Cm (half-life 17.9  years). These
elements stay radioactive for about 148 and  179  years-longer than  the
life of most people, especially those exposed  to plutonium.

     Staff Response - For a relatively constant  food intake  quantity
characteristic of most per.sons, the annual dose  rate from ingestion  of
transuranium elements is expected  to be roughly  proportional to the
environmental contamination level.  For-Tsuch relatively  short
half-life radionuclides, the initial dose rates  are not  expected to  be
maintained over the entire  lifetime of an individual.

3.   Ilene Younghein

     "..for chronic iradiation due  to Pu-239,  200 bone cancers  will  be
produced per 10^ rad to  a 7 kg skeletal mass.   In terms  of the  dose
to mineral bone, mass 5  kg, utilized in this analysis, there results
yield 140 bone cancers.per  rad to  osseous  tissue." This section is
unclear at besti at worst incomprehensible.

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      Staff Response - The statement is a simple scaling of a result
 obtained from the technical literature to the slightly smaller bone
 mass used in the EPA analysis to provide consistency with ICRP models.

 4.    Commonwealth Edison
      Although the proposed guidance seems to apply to all Federally
 licensed facilities with any transurariics in their systems, it would
 be technically unjustifiable to require nuclear power plants to
 conduct environmental surveys following every planned release of
 radioactivity to prove that the derived contamination guidance has not
 been exceeded.   •          •-.••••     '                       .       • .

      Staff Response  - Federal Radiation Guidance is applicable only
 to the  Federal  agencies and is advisory to'the States.  It is prudent,
 however,  for  Federally licenced facilities to evaluate the impact of
 unplanned releases  that are sufficiently large to cause dose levels to
 populations of  the  same order of magnitude as the guidance     <
 recommendations.

 5.   National  Council on Radiation Protection and Measurement

      The  screening  level derivation in Annex II does not reflect  the
 requirements  of the remainder of the document.   Only the ambient  air
 concentration is used and even this is calculated by a mass loading
 technique  with  an enrichment  factor that has not been justified by an
 experimental  work.   We find,  for example,  that  ingestion for the-
 reasonably serious  home garderner could be of importance if the
 uptakes from  the GI tact from Annex III are  used.   This is
 particularly  true for the nuclides other than plutonium.         '

      We recommend a detailed  study of  all  pathways in derivation"''of
 the  screening level with some emphasis on  size  of the area.   In **
 particular, the inclusion of  the enrichment  factor which apparently
makes a difference  on only a  factor of 1.5 and  has never been
 demonstated to  be proper should  be reconsidered.

      Staff Response - The staff  has analyzed the situation where  the
entire surface  inventory of 0.2  uCi/m2 consists  of transuranium
nuclides other  than plutonium.   These  nuclides  generally have higher
plant uptake  and GI tract transfer factors and,  therefore,  result  in
higher doses.  However,  the dose  rates are not  projected to  exceed the
guidance limits even  for  the  serious home  gardener.

     A discussion of  the  applicability of  the enrichment factor can be
found in comment 30 of  Section 3.2.

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 ^"   Jefferson County Health Department'

      It must  be noted that although "soil contamination levels can be
 related to a  corresponding air concentration by use of a resuspension
 factor", in the copy of the proposed guidelines it is admitted that
 such a  resuspension factor may vary by a factor as large as one
 million, which makes the use of such factors highly questionable.  The
 guidance states on page 60958 that a soil contamination level of 0.2
 microcuries per square  meter (with samples collected at the surface to
 a depth of 1  cm.  and including particles less than 2 millimeters in
 size) would establish a reasonable "screening level".  The use of
 whole soil samples to evaluate a hazard from respirable dust is
 inappropriate and will  underestimate the hazard, as I have ,    .
 demonstrated  in my work around the Rocky Flats plant in Jefferson
 County.   In, addition, the value proposed is too high to be acceptable
 to  the  general public,  in my opinion,  if the public understands the
 range of estimates of ill effects that could result in a total
 increase in all neoplasms of perhaps 1 to 2% over a .period of 70
 years.   The incidence of all genetic disease.could increase by 1% and
 ill  health related to chromosome mutation by about 7% for all
 succeeding generations  from the. proposed guidance dosage level.

     Staff Response - Annex II of the  Proposed Guidance document
 discusses  in  detailed the difficulties involved in applying the
 resuspension  factor concept to predicting the  resuspension of surface
 soil.   Because of the many limitations of the  resuspension factor
 concept,  the  agency staff chose not to use it  when deriving the soil
 screening  level.   Instead the  staff used the average airborne mass
 loading  when  deriving the soil screening level, after some
modification  to account  for the distubution of/activity with  soil
 particle  size.

     It  has not been demonstrated that the soil sampling and  analysis
 techinque  proposed  by Dr..Johnson correlates in any way with  the
airborne4concentrations  observed in Jefferson  County.   In fact, since
 this analytical technique drastically  alters the distribution of
activity with  soil  particle size from  what it  is in the environment\
 it is doubtful  that  any  such correlation can be made.   The staff has
compiled a  detailed  critique of the  sampling and analysis  method  .
proposed by Dr. Johnson.  (  See Section 8).

     Additionally,  the staff has  identified  several erroneous
assumptions made  by  the commentpr in converting levels  of  resuspended
dust into dose  from  inhalation.   These errors  result  in projected
doses far exceeding  those which  would  actually  be  received by persons
living in the vicinity of  land  contaminated  at  the  level  of the.
0.2 uCi/m2. (See  Section  8)

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7.  Jefferson  County  Health  Department

     In paragraph  two on  page seven,  the  report  states "the uptake by
plants is  relatively  small,  and most  animals,  including humans,  have a
high discrimination factor against  transfer  of these elements  into the
body tissues".  However,  some plants,  such as  algae and seaweed, have
the ability  to  concentrate plutonium,  presumably in a form that  can be
assimilated  by  animals.   Chelating  agents present in soil  over a
period of  time  may make the  plutonium oxide  in soil available  for
uptake by  both  plant  and  animals to a greater  extent.

     Staff Response - The uptake of plutonium  by plants has been the
subject of numerous laboratory and  environmental studies.   These
studies have demonstrated a  low uptake by terrestrial food plants.
The uptake factors are typically in the range  of 10"^ to 10"^.   It
is true that some  marine  plants show  higher  uptake factors, but  their
contribution to the American diet is  very small.

     The Guidance  establishes a limit  on  doses from all pathways to
which persons are  exposed and,  if a situation  arises where the marine
food pathway is significant,  this would not  invalidate the Guidance.
Likewise increased solubilization which increases the uptake of
plutonium  by plants would not invalidate  the Guidance.

     Several mechanisms have  been suggested  which can increase the
solubility of plutonium.  Much  of this research  is in the  preliminary
stage and  a  quantitative  discussion of the time  required for such
transformations is not currently possible.   The  preliminary data,
however, have not  demonstrated  that rapid transformation of plutonium
occurs under conditions generally encountered  in the environment.
Most likely, if such  transformations  do occur,  they occur  over long
periods of time (decades).

8.   Jefferson  County Health  Department

     The table  on  page five  (table  1.2) indicates a soil concentration
of 0 to 1,000 picocuries/gram (pCi/g)  of  plutonium on site. However,
these values have  been previously reported to  be as great  as
13,600,000 pCi/g (INV-10  report)*.  Therefore, to say that the onsite
maximum is in excess  of 1,000 pCi/g seems misleading.   The same
comment may  be  applied to the level given for  plutonium in soil  at the
plant site boundary.   As  much as 80 pCi/g has  been measured in samples
of surface respirable dust off  site.
* "Levels of 2 x 105 dpm/g to over 3 x  107 dpm/g reported."

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     Staff Response — All  uncontained  on-site soil at the Rocky Flats
Plant  site contaminated  above  2000  pdi/g (about 21,000 square feet) is
currently being  removed  by DOE.

9.   Jefferson County Health Department

     In addition to resuspension  of plutonium from surface dust, we  ,
must also consider the release of particulate plutonium from
plutonium-processing plants.   These particles are for the post part
less than five microns (micrometers) in  size  and large numbers are  -
released at  times.  Eight  days after a fire at Rocky Flats in 1957, as
many as 125  million of such five  micron  particles or .their equivalent
were released in a single  day  from  one stack.  A two micron particle
of plutonium oxide, if inhaled, would  produce a dosage of over two
millirem to  bone.  A particle  five  microns in size could be inhaled
and retained and produce a dose about  40 millirem to the lungj 1,700
millirem to  the  tracheobronchial  lymph nodes, over 130 millirem to the
bone,  50 millirem to the liver, eight  millirem to the kidney, and two
millirem to  the  gonads, where  a pattern  of microdeposition of
plutonium would  give a proportionately greater effect than the same
order  of size as bacteria,  and may  be  blown by the wind for great
distances.   A single particle  only  two microns in size, if;inhaled and
retained, will produce a dosage exceeding the EPA 4 millirem annual
dose.

     Staff. Response - These recommendations are to be used only for
guidance on  possible remedial  actions  for the instances of existing
contamination or of possible future unplanned releases similar to the
incident described.                                                    .

     The agency  staff does  not agree with these dose calculatins.  As ,
indicated earlier, the agency  staff has  identified several erroneous
assumption made  by the commentor  in converting from levels of
resuspensed  dust to inhalation doses.  These  are described in
Section 8 of this document.

10.  Jefferson County Health Department

     On page 28  (implementation)  the guidance states t"in most cases
the critical pathway for exposure to transuranium elements is through
inhalation of airborne particulates  derived from resuspension of soil ,
particles and compliance with  this  dose  guidance can be demonstrated
by measurements  of air and/or  soil  concentration".   The problem with
the use of soil  samples (agricultural  soil) is that much of this
material is  coarse and is not  windblown, and  when included in the
samples used to  evaluate windblown  material,  misleadingly low results
are obtained.  The best way to evaluate  a hazard from airborne
contaminated dust is by use of a  respirable dust sample from the
surface of the soil.

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     Staff Response - Regardless of the soil sampling  technique, a
relationship must be established between the measured  soil
contamination and the actual airborne activity.  Dr. Johnson has not
established such a relationship for his respirable dust sampling
technique.  Even if a satisfactory correlation could be established
for the sampling method, the Dr. Johnson's techniques  does not
correspond with the lung deposition models developed to calculate
inhalation doses.  These models require a value  for the total airborne
activity and a description of the, distribution of that activity as a
function of particle size.  Dr. Johnson's technique does not provide
such data and therefore does not provide a method for  evaluating the
potential inhalation hazard.         ,,         ,      ,   • , . , .

11.  Jefferson County Health Department

     There are problems with the estimation of the air concentration
of plutonium due to the efficiency of filters used in  air monitoring
devices, the velocity of air intake, the variation in  concentration of
resuspended plutonium by height above the ground surface, and other
local factors.  In addition, such measurements are given in averages
per cubic meter whereas plutonium is particulate, i.e., the inhalation.
of one particle of respirable size (two microns) per year would exceed
the 1976 EPA regulations.  The effectiveness of  such filters in       s
retaining the orders of sizes of plutonium oxide smaller than 0.1
micron needs to be evaluated.  I would agree with the  guideline that
"therefore soil measurements may be more advantageous  in certain
areas" except that these should always be performed.         l

     Staff Response - There are problems with any method of measuring
environmental contamination level, whether it be in air, soil, or.
water.  Such measurements are difficult because  of the generally low
concentration levels, non-uniform distribution,  and other similar
factors.  The collection efficiency of filters and of  other sampling
devices can generally be determined and appropriate correction made in
the reported results.

     The agency staff prefers the measurements of airborne   •-.
radioactivity to soil measurements when evaluating an  inhalation.
hazard, for the following reasons:

         1.  Air measurements provide a method for averaging over
         larger volumes than do soil measurements.

         2.  Air measurements show less point-to-point variation.  ,
         Values of soil concentrations can vary  dramatically over a
         distance of only a few meters.  How this variation will be
         reflected in the overall inhalation risk is difficult to
         evaluate.

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          3.  Air monitoring can be performed on  a  continuous  basis  and
          therefore provides a method for averaging over many  changes
          in climatic factors.

          4.  Air measurements provide a method for evaluating the
          impact of a contaminated area which is  some distance from  the
          population at risk.
                      • ' "   .  '     .• .  \         -   -        '.  •   "I  .  ' '', .
          5.  Measurements of the radioactivity in  the air to  which
          populations are exposed can be more directly correlated with
          the potential inhalation hazard.  Soil measurements  require a
          calculational model to relate  the soil levels to the       '
          resuspended activity.  Such models introduce uncertainties
          and, therefore,  must be conservative in nature so that the
          actual inhalation hazard is not underestimated.

 12.   Jefferson County Health Department

      The soil sampling  suggested by the agency is agricultural soil,
 ie., ..partible sizes  under two millimeters in size,  collected  to a
 depth of one centimeter.   This type of sample is  inappropriate for use
 in evaluating a hazard  presented by-contaminated  respirable dust.  The
 suggested "screening level"  for  soil  contamination' of 0.2 microcuries
 per square  meter is  equivalent to about 29  disintegrations per minute
 per gram, assuming a soil density of  1.5 gram per cubic centimter, and
 is a  concentration much too  high to be  considered safe  for residents
 of such  areas.   This  level is  about 15  times greater  than that now   '
 recommended by  the Colorado  State Health Department (0.01 microcuries
 per square  meter^ or  2  dpm/g)  except  that the  state interim standard
 is addressed  only to  plutonium,  and does  not include  other
 transuranium  elements.  Samples  of  respirable  dust  compared  to whole
 soil  samples  collected  by the method  used by the  state  have  indicated
 as much  as  285  times  as much contamination  with plutonium as  indicated
 by whole  soil samples.  Plutonium in  the  surface  respirable  dust
 offsite  is  as much as 3,390  times the background  value  from  fallout  in
 Colorado.   Therefore, I believe  that  the  use of whole soil sampling,
 as advocated by  these proposed guidelines,  is  inappropriate and will
 certainly underestimate the hazard.

     Staff  Response - The Guidance recommendations  refer  only  to dose
 rates to organs of persons in the general population.  Comparisons on
any other basis are inappropriate.                         .

     A critique of the respirable dust sampling method proposed  by Dr.
Johnson is  contained in Section 8 of this document.
                                       51

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                                    oersistence  is  not  a  requirement
                                    *38Pu daughter  of 242Cm is  not
2.6  Miscellaneous Comments

1.   Department of Energy

     Footnote is misleading.  Long
for environment impact.  Also, the
shortlived,  (p-2, Table 1.1)

     Staff Response - We agree.

2.   Department of Defense

     "more or less uniformly" is an ambiguous and misleading
description of the extensively studied distribution of fallout.
(p-3, lines 8-10)

     Staff Response - The wording is meant to convey the idea that,
while local concentrations may vary from the mean by up to a factor of
two, fallout represents a relatively constant fraction of the total
background level in the United States.

3.   Department of Defense        s

     "More or less uniformly" is ambiguous and misleading with regard
to fallout.  Why not just state that fallout has been slowly deposited
over the lands and oceans and the level now is x microcuries/meter2?
(p-3 lines 8-10)

     Staff Response - Fallout has not been deposited entirely
uniformly and varies by more than a factor of four from the lowest to
the highest current soil concentration level.  Designation of an
"average" background level of "x" microcuries/meter^ would be
erroneous and misleading.
4.   Department of Energy

     "The principal modes of transport" are not as certainly
established as this sentence would suggest.  (p-4, lines 13-16)

     Staff Response - The agency staff has considered information
applicable to all modes of transport to man to the extent available in
the literature, and believes this to be sufficient to support the
Guidance recommendations.
                                      52

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5.   Department of Energy

     Title of table might more appropriately refer to transuranics
rather than plutonium, since 20,000 Ci of U.S. fallout must include
241Am.  If only plutonium, the U.S. fallout inventory is 16,000 Ci.
(p-5, Table 1.2)

     Staff Response - We agree.

6.   Department of Energy

     Several inventories and concentrations noted as "greater than"
have little meaning.  How much greater than?  The comparison between
  45 Ci listed for the Trinity Site and   155 Ci listed for the Nevada
Test Site suggests that "   155" must mean "very much greater than,"
since it seems that the single small test at the Trinity Site would
produce insignificant fallout compared to the many tests at the Nevada
Test Site.  This njay not be true but the reader may well draw such a
conclusion,  (p-5, Tabel 1.2)

     Staff Response - The data were derived from various sources and
indicate best estimates of the Department of Energy.

7.   Department of Energy

     Listed soil concentrations have no va|ue without specification of
sampling depth.  The footnote seems to imply a 1 cm depth, but this is
probably not applicable to all values.  It would aid comprehension if
all soil levels throughout the document were converted to an area
basis rather than leaving it for the reader to make such a conversion,
which he often cannqt make because of lack of information on sampling
depth and soil density.  (p-5, Table 1.2)

     Staff Response - Conversion of measurement results is only
possible where all the data are available.  Sampling depth, variation
oftconcentration with depth, soil density, and other variables are
often not explicitly stated and would make the results of conversions
aft|biguous.  Additional details for specific sites are given in Annex I.

8.   Department of Energy

     There are numerous inconsistencies between Table 1.2 and Table A
1-5 of Annex 1.  These two tables should either be identical, or one
should be abstracted from the other,  (p-5, Table 1.2)

     Staff Response - We agree.
                                     53

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 9.   Department of Energy

      There is a major problem with  Savannah River  Plant  data, which
 cannot be verified in references cited  in Annex  I.  The  total
 inventory should be 1-2 Ci.  "N area" should be  "H area."  The  correct
 numbers are:  for H area, 0.41 pCi/g; for F area,  0.08 pCi/g; and  for
 perimeter, 0.01 pCi/g.

 These numbers are derived from data presented in McClearen, H.  A.,
 "Plutonium in Soil at the Savannah River Plant," DPSPU 74-30-14, AEC
 Environmental Protection Conference, Albuquerque,  NM (1974).  (p-5
 Table 1.2)                                            ...**»

      Staff Response - We accept the Department of Energy correction.

 10.  Department of Defense                 =              «
                                                              1
      What is the significance of light lines vs heavy lines in  the^  "
 schematic?  (p-6,  Fig.  1)

      Staff Response - Heavy lines are intended to represent the more
 significant pathways.

 11.  Department  of Energy

      Caption should explain significance of different  kinds of lines.
 Arrowhead is  omitted  on  line from water  to sediments,   (p-6,  fig. 1)

      Staff Response - We agree.   (see DOD comment 10)

 12.   Department  of Energy

      ^^Am is probably more  important  than  238pu>  (p-7,  line ,23)

      Staff Response - Am-241  is only more important in weapons grade
materials.

 13.   Department of Defense

      The inference concerning biology  is  loose.   It is not  established
that  the pulmonary region is not a probable site  for plu.tonium induced
cancers nor is it true that plutonium  oxides may  contribute only
marginally to bone cancer,  (p-9, para 1  and 2)

      Staff Response - The information  given here  is  specified as
applicable only to the inhalation pathway.  Details  on the  assumptions
used  in dose calculations are given  in Annex III.

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14.  Department of Energy

     The pulmonary region may well be the most probable  site  for
plutonium-induced cancer in humans.  (p-9,  lines 4-6)

     Staff Response - The statement  in  the  document merely  says  that
the Agency combined the two more conservative assumptions.

15.,. Department of Energy        ,                     , ,.     ••• ••..-• -:<'"*•'

     Some forms of plutonium oxide,  particularly 238Pu02, may be
rather quickly translocated to bone.  In  such cases  the  frequency of
bone tumors may exceed that of lung  tumors.  (p-9,  lines 11-14)

     Staff Response - True.  The more isoluble forms  of plutonium oxide
do  translocate quickly and increase  the risk of bone  and liver
cancers.  However, in that case, the risk of lung  cancer is decreased
because of the shorter residence time in  that organ.,  (See  Section :6)

16.  Department of Energy                     ,                    ,

     "dpm/g in the top 1/8 inch  of soil"  should be translated into
units used elsewhere in the document.   (p-11,  line 17)

     Staff Response - The units  are  stated,as given in the  applicable
Colorado  standard.                  .             ..,,,.

17.  Department of Energy

     Here and  elsewhere  in  the  Summary  Report,  it  would be very
helpful  if more specific  references  were  made to material in the
Annexes,that  support  the  conclusions stated.  The  lack of supporting
justification  in  this Section  is acceptable only  if one is explicitly
directed  where  this  justification  can  be  found,   (p-14,  Sec. 2.4)

     Staff Response  -  In  the  absence of more detailed and definite
information,  an  answer  cannot  be provided  for this comment.

18. Department of Energy            .      .        „         ,,

  '"• This sentence is  grammatically^confusing and difficult "to follow.
(p-14,  lines  17-21)           !      "\" " t '               •

     StaffResponse -  We believe the intent to be clear. r  ,  |

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 19.  Department  of Energy

     The  first criterion,  by  use of the  words  "very small,"  almost
 seems  to  preempt the  second criterion.   What happens if  implementation
 at a "very  small" risk  level  is  not feasible?   The  occurrence  of such
 ambiguities here and  elsewhere  tends to  reduce the  effectiveness of
 the document.  (p-14, lines 21-25)

     Staff Response - The  ambiguities  referred to may be in  the  eye  of
 the beholder.  The agency  staff  believes that  DOE estimates  of costs
 are greatly excessive and  that a very  small risk level and achievable
 costs  of  implementation are compatible in most cases.

 20.  Department  of Defense

     To what does "change  by  factors of  10" refer?   Is it costs,  soil
 concentrations,  calculational precision? This is unclear.
 (p-10, line 10)

     Staff Response - "changes of factors of 10" is  intended to  apply
 to soil concentration.

 21-  Department  of Energy

     The  intended meaning  of  "beyond the boundaries  of the source from
where  it  orignated" is  not clear.   Does  this mean off-site?
 (p-18, line 2-3)

     Staff Response - Yes.

22.  Department  of Energy

     The  term "numerical guide"  is  ambiguous.  What  exactly  is meant?
(p-18, line 23)

     Staff Response - The  term refers to the numerical guidance
recommendations.

23.  Department  of Defense

     In view of  later comments on Annex  VI, this table adds nothing
for the summary,   (p-19, Table 2.1)

     Staff Response - The table  is  intended to give  a  comparison of
impacts at alternative  guidance  recommendation levels  and may be
useful from that viewpoint.

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24.  Department of Energy                                      -

     The term "numerical guide" is ambiguous.  If, for example,, it
were interpreted to mean "screening level," the statement would be
incorrect.  (p-20, line 1)

     Staff Response - See response to comment 22.

25.  Department of Energy           •                          ;'•

     The appearance of the official "Text of Proposed Guidance" at  the
end of the section that discusses it, is awkward.  It would be easier -
to understand the discussion if the Guidance appeared at the  beginning
of this section and was followed by discussion which went somewhat
farther in justifying the exact form of the Guidance,  (p-20, line  19)

     Staff Response - Section 2 of the Summary document discusses the
rationale for the proposed Guidance.  The text follows logically.

26.  Department of Defense                               ,

     This chapter supposedly has the purpose of summarizing the
proposed guidance, yet the proposed guidance does not appear  until
page 20.  As a matter of writing style and to improve clarity, why  not
introduce the chapter with a statement that EPA, under its appropriate
authority, is proposing guidance for transuranium elements, etc., the
text of the proposed guidance is etc., and then follow with the
discussion.  It is now presented awkwardly if not backwards.
(p-20, Section 2.5)

Staff Response - See response to comment 29.

27.  Department of Energy

     It does not appear that the Guidance, as stated here, would
permit exceeding the dose  limits on the basis of risk-benefit
considerations.  This seems unfortunate.  For example, the very  low
risk incurred by exceeding the  specified limits by  some  small factor
might well be acceptable  if the alternatives  to cleanup  lead  to  an
uhacceptable risk-benefit  ratio,   (p-21, lines 3-4)

     Staff Response - Guidance  recommendations retain  flexibility of
implementation.Deviations may be permitted when properly justified.

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  28.   Department of Energy
       • I • III ..II •Illl ••••.« I •! I .!•! . | „ . | .I.., , ,                                      f, ,

       "Guidance on possible remedial action" sounds very weak   What
  exactly does  it mean?  It should be explicitly defined in the text of
  the Guidance.   (p-21,  lines 11-12)


       Staff Response - We agree.   The text has  been changed.

  29.   Department of Energy


       Definition of "critical  segment of  the  exposed  population"  is
      Staff Response - The guidance limits apply to that group of
 persons in the general environment who, because of residency or other
 factors can on the average be expected to receive' the highest lifetime
 radiation dose from a specified source of transuranium elements,

 30.  Department of Defense

      Definition a.  "Critical segment of the exposed population" is
 vague,  Definition d   replace following with during.   Definition g.
  general environment" means  all the environments outside the
 boundaries of Federally licensed or controlled facilities, does  this
 mean that lands inside the boundaries of similarly controlled
 facilities are exempt from the guidance?  Definition  h.   Why define
  curie   when  it has not been mentioned or employed previously.   One
is
     Staff Response -  a.   "Critical  segment  of the  exposed population"
    defined above; b.  we  agree;  c.  yes.  The guidance  is applicable
only to those persons  residing  outside  the boundaries  of Federally
licenced or controlled facilities; d.   see response  to comment  32.

31.  Department of Energy

     "Equilibrium dose rate following chronic  inhalation"  is
incorrect.  It should be changed  to read, "equilibrium dose rate
during chronic inhalation."  (p-22, lines 3-4)

     Staff Response - We agree.

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32.  Department of Energy

     Since."curie" is not  employed  anywhere  in the Text of Proposed
Guidance, why  is  it defined here?   If mCi  and fCi are to be defined,
why not uCi, nCi  and pCi?  (p-22,  lines  17-21)

     Staff Response - The  definition should  be deleted.       '; ; .

33.  Department of Energy                                   ...,:.;

     The "small fraction"  translocated is  not small,   (p-25,  line 6)

     Staff Response - The  solubility of  most inhaled  transuranium
nuclides is small and therefore  the fraction dissolved in the
bloodstream is necessarily small.

34.. . Department of Energy      . :  -     *.  •;  .-  >..  ••„ *.-.  '•'-.   ,;  '   '    r

     This sentence should  be  referenced  to the place  in this  Guidance
where bone and liver cancer risk is derived,  (p-25,  lines 18-22) ,

     Staff Response - The  section  is a summary of the detailed
evaluations in Annex 3.

35.  Department of Energy                                      •-..-•

     The term "cohort" should be defined.  (p-25, footnote)

     Staff Response - The  definition of  "cohort"  as used dn the
Guidance is":  a group of 100,000 individuals with age in common.   In:
the analysis, the mortality experiences  of all the members of the
cohort are traced from birth  to  death.

36.  Department of Energy

     This sentence should  be  referenced  to the place  in this  Guidance
where genetic risk is derived.   (p-26, lines 16-17)

     Staff Response - Genetic risks is discussed  in detail in Annex 3.

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 37.  Department of Energy

      The genetic risk to succeeding generations is confusingly and
 inaccurately stated.  The numbers quoted are an equilibrium rate
 assuming continuing exposure, generation after generation.  The term
  as high as  is confusing, when followed by a range.
 (p-26, lines 19-22)

      Staff Response - We agree, see Annex 3.

 38.  Department of Defense

      Replace and with either £s or since.   (p-27,  line 3)

      Staff Response - The sentence reads as intended.

 39.  Department of Energy

      The term "environmental radiation dose commitment" should be
 defined,   (p-27)

      Staff Response - The definition of "environmental radiation dose
 commitment  as  used in the Guidance is:   "the  total  dose accumulated
 by  all  individuals in a given population over  a designated period  of
 time."

 40.   Department of Energy

      This  sentence  has  a syntax problem.  The  conjunction "and" should
 be  changed to "since,"  or,  better,  dropped  to  form two sentences.  The
 content of this sentence  is  important  and deserves greater emphasis
 than  it  is  given,   (p-27,  lines  23-25)

      Staff Response - The  sentence  reads as  intended,  and  represents
 parallel conclusions.

41.  Department of Defense

     The use of "over a prolonged period of  time" is another example
of using non-specific quantifying phrases and has no meaning—is it a
year, 10 years, lifetime or what?   (p-28, line 5)

     Staff Response - The phrase is purposely non-specific  to avoid
the impression that only a lifetime exposure is significant.
                                   60

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                                   10
42.  Department of Energy

     A "prolonged period of time" should be more explicitly defined.
(p-28, line 5)

     Staff Response - See comment 41.

43.  Department of Energy

     "Bites and stings" should be attributed to venemous animals and
insects.  Electric current is not hazardous when confined to "home
wiring and appliances."  The fatalities should be attributed to
electrocution or electric burn or shock,  (p-28, lines 6-7)

     Staff Response - The meaning would seem clear  to the intelligent
layman.

44.  Department of Energy

     It  should be made  clear that the  purpose of these soil
measurements  is to locate the specific areas of contamination.
(p-29,  lines  2-3)

     Staff Response - We agree.

45.  Department of Energy

     "Suggests" may be  too weak  a word;  "recommending" might  be  more
appropriate,   (p-29,  line  12)

      Staff Response - We  agree.

46.   Department  of Energy

      Specification  of particle  size seems an unnecessary complication
 for  a "screening level" already  burdened with many conservative
 assumptions,   (p-29,  line  14)

      Staff Response  -^ The  specification limits  the inclusion of  large
 particles,  and follows  the definition of "agronomic soils."
                                    €1

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                                     11
 47.  Department of Energy

      This paragraph is an example of the imprecise wording that
 deprives the Guidance of practical utility,  (p-28, lines 18-23)

      Staff Response - We believe the wording to be precise and the
 intended meaning clear.  The paragraph admonishes the implementing
 agencies to consider all pertinent pathways.

 48.  Department of Defense

      Overall, the chapter does not read well, is constructed poorly
 from the standpoint of style and clarity, is imprecise and lacks
 definite statements.

      Staff Response - de gustibus non disputandum est.

 49.  Ilene Younghein

      If we continue with our present nuclear energy plans, by the year
 2000 we will have accumulated roughly 1.6 million pounds of
 plutonium-including plutonium from breeders-according to estimates by
 Glenn Seaborg.   Even  with 99.99 percent storage reliability,  the
 nuclear industry will  release 160 pounds of plutonium each year.   If
 1.6 micrograms  can cause cancer in a non-smoking adult - that is
 enough to  provide minimum potential  lung cancer doses  for about 15
 times earth's present  population.

      Staff Response -  Control and  accountability of plutonium is
 orders  of magnitude better than the  number  stated,  and is expected to
 improve.   The assumption that the  entire  release is  transferred
 through the  environment  to become  the body  burden for  humans  is
 patently absurd.   Transfer and  uptake mechanisms are discussed  in the
 Technical  Summary.

 50.   Ilene Younghein

      Section  1.2  is vague. You  said more  recent  weapons  tests have not
 added  significant  amounts  to  this  level.  What  do you mean by
 significant?  Also what  do you mean by  significantly higher amounts  in
 refering to Bikini  and Enewetak.   Is that a way  of avoiding how much
radiation is  really there.  Other mushy language  is about  the
underground detonation where you said that it is contained below  the
earth's surface and is not expected to be readily avilable for  uptake
by humans.  Areas of high  concentrations may be well documented,  but
long terra health effects have not.  The fact that most of  the

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                                   12
contamination is on Federally owned property says .something about the
carelessness to which public trust, is carried out.  Everybody's land
is nobody's land.

     Staff Response - a)  "Significant" changes of environmental
contamination levels are usually considered to involve,increases of at
least twice the standard deviation of observed values.

     b)  Data for Enewetak atoll are given in Annex I.

     c)  The guidance is concerned specifically with doses to humans
and considers availability in those terms.

     d.)  The subject of long-term health effects  resulting from
exposure to alpha particle radioactivity is under continuing review.
The guidance is based on' best available'current information.,

     e)  Production of plutonium, fabrication, and testing of weapons
are necessarily carried out in areas restricted to the public.  The
Federal government purchased land for these specific purposes,
including surrounding "buffer zone" areas.

51-  Ilene Younghein

     Section 1.3, Other modes of resuspensipn of  airborne particles
could be traffic, and plowing.  "Discrete particles" is  cosmetic
language.  Separate particles would be a better use of the language.
No way can a particle of Pu 239 be called discrete.  The statement
that the uptake by plants is relatively small is  misleadirig.  Plants
have been know  to accumulate plutonium and concentrate it in.their
systems, and your statement that most animals, including humans have  a
high discrimination factor against transfer of these elements into
body tissue is  questionable.  For sure, plutonium deposited  on  the
skin can cause  cancer.
     Staff Response -   a)
man-made disturbances.
Traffic and plowing are examples of
     b)  Discrete  is' not  discreet  (see  dictionary).

     c)  The  agency  staff has  considered  all  available  information on
plant uptake.  No  reference  was  found to'substantiate concentration in
plants.

     'd)  Discrimination  factors  for  biological  uptake of ingested
plutonium  are based  on best  available information.

     e)  There is  no evidence  that plutonium  deposited  on the skin can
cause cancer.  Even  if plutonium penetrated the skin the expected
result would  be  development  of a foreign  body granuloma or fibroma.
(See Lushbaugh,  et al., Ann. N.  Y. Acad.  Sci. 145:791-797 (1967))

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                                    13
 52.   Ilene Younghein

      The makeup of your Working Group is suspect.  Both ERDA and NRC
 have and still actively promote nuclear energy.  NASA uses nuclear
 satellities,  and the Department of Defense is responsible for most of
 the  contamination from the transuranic elements.  Under the DOD we
 have gone from the average fallout of .06 pCi/g to 18,000 pCi/g in
 Nevada.   This may be a reason for the high cancer rates in Nevada.
 Plutonium levels now measure 1000 pCi/g at Rocky Flats, Colorado.
 Cancer and leukemia rates have reached almost epidemic proportions in
 North Denver, and in Mesa County - home of the uranium tailings.
 Rather than try to cut down on radioactive contamination, the State of
 Colo,  has accommodated themselves to it, and raised their levels of
 allowable pollution to twenty times fallout.

      Sjiaff Response - a)  The function of the Working Group was to act
 in an advisory capacity and to make available to the EPA the technical
 expertise of  these agencies.  The Federal Radation Guidance is subject
 to interagency review and signed by the President.

      b)   The  past or present association of an individual with nuclear
 energy or nuclear weapons is not considered a deterrent to his
 providing developing technical expertise relevant to radiation
 protection.

      c)   The  statements referring to cancer and/or leukemia
 "epidemics",  and the rationale for the current Colorado standard are
 irresponsible and not  based  on fact.

 53.  National Council  on  Radiation Protection and Measurements

     The  documentation and  information used from the  reference is
 frequently in error.   There  are  a  number of cases  where the  reference
 does not  discuss  the subject matter  at hand.   In several  others,  a
 review of  the reference leads  to conclusion different  from those
 quoted.   In at  least one  case, a qualitative  statement  was made  about
 the results when  a quantitative  statement  is  needed  to  justify the
 conculsion.

     We recommend a vigorous review  of the  references and  the  material
used in the report in  order  to provide an  accurate indication  of  the
 important material.

     Staff Response -  In  the absence of more  definitive information,
no response can be provided for  this comment.
                               64

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                                    14
54.  N.Y. Federation for Safe Energy

     The proposed guidance is incomplete in that  it does not  take  into
account the many sources of radiation individuals are exposed to due
to industry and commercial uses of radioactive products, as well as
additional radioactivity released from operating  facilities such as
Millstone and Fort St. Vrain, which are just  two  recent incidents  that
come to mind.

     Staff Response - The guidance provides recommendations only for
transuranium elements in the general environment.  None of the  sources
terms mentioned are applicable.

55.  Jefferson County Health Department

    'Why are dosage rates (page 17) expressed in  terms of millirad per
year (mrad/yr), since the term "rad" does not include the relative
biological effectiveness factor for the type  of radiation involved?
The U.S. Environmental Protection Agency (EPA) water quality  standards
published in 1976, for example, give standards for exposure to
radiation in millirem.

     Staff Response - The Guidance limits are applicable to alpha
particle emitters.  Therefore both dose and risk  estimates are
expressed in a more fundamental physical unit, the rad, which is a
measure of the specific energy imparted.  This approach is more
straightforward and periodic revision of the Guidance will not  be
needed to account for differences between various kinds of radiation.
Further information on health effects will, however, be factored into
these guides as the need arises.
                                     65

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            3.  RESPONSE TO COMMENTS ON ANNEXES I THROUGH ¥1


3.1 Annex I - Transuranium Elements in the Environment
     Comments of an editorial nature were accepted where appropriate
and will be reflected in future publications of this Annex.  Reference
22 of Annex 1 should be changed to: Douglas, R.L. "Data Report -
Levels and Distribution of Environmental Plutonium Around the Trinity
Site," ORP/LV-78-3, USEPA, Office of Radiation Programs, Las Vegas
Facility, Las Vegas, Nevada 89111 (1978).

1.   Department of Energy

     Although included in the list on p. 1-1, the possibility of
future accidents involving nuclear weapons and satellite power sources
is not discussed.  This iss based on past experience, a more probable
"source for future release of the transuranium elements to  the general
environment" than "operations associated with the Light-Water Reactor
Fuel Cycle."  (p-1)

     Staff Response - The relative probabilities of  future  releases
from these sources are not well known but we agree that future
uncontrolled releases to the general environment could occur from
operations other than those associated with the Light-Water Reactor
Fuel Cycle.

2.   N.Y Federation for Safe Energy

     Page 3 states the major portion of the transuranium elements in
the environment is the result of nuclear weapons tests during
1945-63.  Was 1963 the last nuclear test that was considered in  total
fallout?  If so, the French test of 1976, the "dirty" Chinese tests of
1976 and 1977, should be included, as well as any radioactivity
released by the Cosmos crash last month,  (p-3)

     Staff Response - Tables in Annex  1 include measurements on
plutonium in fallout through 1975.  Tests after 1975 have not
significantly altered the environmental levels of plutoniu® in soil.

     The evaluation of existing environmental contamination given in
the technical documents is not intended to be exhaustive, but rather
to give a sussnary of the current status.  Inclusion  of specific  events
is not pertinent to the intent and rationale of the  guidance.

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 3.   Department  of Energy

     The  last  listing in the  inventory column,  "4,000 (Pu-238)" is  not
 correct.   It was probably intended  to be "4000  (Am-241)."

     Staff Response - "4,000  (Pu-238)" should be changed  to "4,000
 (Am-241)."

 4.   Department  of Energy

     The  relationship of the  Tonopah  Test Range to  the  Nevada  Test
 Site should be clarified,   (p-9)

     Staff Response - The Nellis Air  Force Range nearly surrounds the
 Nevada Test Site forming an exclusion area 25 to 100  kms  wide
 (ref. 29,  Annex  1).   The Tonopah Test Range  is  located  in the
 northwest  corner of the  Nellis Air  Force Range  and  is not considered
 to be part of the Nevada Test Site.

 5.   Department  of Energy                                        -

     The old boundaries  within the  new boundaries of  Rocky  Flats are
 confusing  and should be  deleted or  explained.   (Fig.  A  1-6)

     Rocky Flats  boundaries should  be updated.

     Further explanation is required  for the  numbers  on this figure,
 some of which are isopleths and some  of which are sampling  locations.

     More  recent  surveys  show better  estimates  of these isopleths.

     The statement  that  "plutonium  in soil (offsite areas)  is  less
 than 0.1 uCi/m2"  is  in apparent disagreement  with Fig.  A  1-7, which
 shows a 0.5 uCi/m2  isopleth extending beyond  indicated  plant
boundaries.  An up-to-date version of Fig. A  1-7 might  eliminate this
problem.

     Some  attempt  should be made to relate the  5 cm deep  samples
discussed  here to  the  1 cm deep samples  of the  Guidance screening
level.  It is otherwise possible to mistakenly  conclude that the Rocky
Flats samples could  exceed the screening level.

     Staff Response  - An updated map  of  the Rocky Flats site showing
the new boundaries and isopleths in units of uCi/m2 is  shown in fig.
2.4-24 of  the "Draft Environmental Impact Statement - Rocky Flats
Plant Site, Golden Colorado", ERDA-1545-D, (Sept. 1977).  This  is
reproduced on the following page.
                                      88

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                              >/V  GREAT	""-•-
                              J*' \WESTERN  •"—•..  ^"-..,
                            -^J«ESERVgR   -X.s X


                               0.05   \   IU
EROA PROPERTY
      BOUNDARY
     FIGURE 3  Plutonium-239 Contours Around Rocky Flats OiCi/m2)

                          (adapted from Kiey, 1970)

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     The relationship between a 5 cm deep samples and a 1 c» deep
sample will depend on the mixing of soil that has occurred. For an
undisturbed site about half of the activity in the top 5 c* would be
expected within the top 1 cm (Annex I, Table Al-2)

6.   Department of Energy

     "Wet weight" or "dry weight" should be specified if these value*
are to be meaningful.  (Table A 1-10)

     Staff Response - Average concentrations in Table A 1-10 are  in
terms of wet weight.

7.   Department of Energy

     Data on core sediment  sample has  no value without specification
of sampling depth.   (Table  A 1-11)

     Staff Response  - Core  samples were collected  by the Hound
Laboratory and are believed to be  1  foot cores.

8.   Department of Energy                                              ,

     It would  be helpful  to know  over  what period  of time  air and
rainwater  samples were  averaged.   (A 1-12)

     Plutonium in  rainwater cannot be  expressed in pCi/ra .
 (Table A 1-12)

      Staff Response - Samples represent annual averages.   The
Plutonium "concentration" should  be plutoniuas "deposition" in rainfall.

 9.    N.Y Federation on Safe Energy

      The referenced proposed Guidance is incomplete in listing sources
 of radioactive materials in the environment now.  Table Al-15 lists
 underground testing conducted off the Nevada Test Site, ref. US AEC
 Jan. thru Dec. 1973.  Since the proposed guidance was not issued till
 Sept. 1977,  why wasn't a recent listing used.  Even the one that is in
 the proposed guidance is incomplete.  One really "dirty"  (and most
 likely embarrassing) NTS test Dec. 18, 1970 "Baneberry" is not even
 listed.  This released a cloud of radioactivity 10,000 feet above  the
 surface exposing some 86 persons to radiation.  In  addition, since
 1973 there have been at least 40 - 50 "announced" tests.  (Al-15)

      Staff Response - Underground nuclear tests on  federally owned
  sites have not released transuranium  elements to off-site areas  in
 quantities that lead to significant doses compared  to guidance
  recommendations.

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                                - -,•<•-- 5       --	     -.-.  -       ...

  10.   Department of Energy-,

       Referenpe should be given.  (Table A 1-24)                      1

       Soil  data have no value without specification of sampling deoth
  (Table  A 1-24).                                                  y  *'

       Staff Response - References  for Table A 1-24 and for Table A-1-25
  are  10,  13,  and 24.

       The soil  samples in Table A  1-24 were collected to^.S cms.

  11.   Colorado  Department of  Health

       Throughout the  supporting documentation  regarding airborne
 concentrations  of plutonium  as related to  soil  contamination levels
 only  ERDA  (now  DOE)  data has been used.  Following the EPA hearing
 held  in Denver  on January 10,  1975,  at your request  the Department's
 air surveillance data  for  the  Rocky Flats  Plant environs was
 provided.  On previous "rough"  drafts  of the  proposed  guidance
 document we have commented that data  other than that provided  by  the
 ERDA  facility have not been  referenced or used.  As  the  State's  data
 identifies levels a  factor of  2-8 higher than the values  provided  by
 the Rocky Flats Plant's  own  surveillance, you underestimate  the
 associated health risk and the costs, of remedial action.  We urge  vour
 use  of all pertinent data in your evaluation and assessment of the
 guidance impact.;             ,

      Staff Response - Table  1 is a partial summary of  some of  the
 Colorado Department of Health data on air concentration levels of
 Plutonium taken, from "U.S. AEG Rocky Flats Plant 1971 Environmental
 Surveillance Summary Report"  Colorado Department of Health, Division
 of Occupational and Radiological Health, Denver, Colorado, and
 succeeding  volumes  in this series  through 1974.

      The  agency staff recognizes that (the data reported by the
 Colorado  Department  of Health are  generally higher than similar data
 reported  by the  Rocky Flats Plant.   Such experimental differences may
 be^indicative of systematic differences in  the sampling and analysis
 methods,  actual  variations .between sites, differences in measurement
 interval, short-term  fluctuations, or  other reasons.  The accuracy and
 precision, of environmental measurements is  necessarily  limited   and
 such constrants  raust.be recognized.  However,  it is  important to
 recognise that none of  the  data presented by the State  of Colorado for
offsite areas around  the  Rocky  Flats  site indicate  that air
concentrations of the  transuranium elements exceed  the  agency's
screening level.  Therefore,  few,  if any, remedial actions are
expected tp be necessary  for  .this site, and the costs have not  been
underestimated.

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                                                        TABLE 1

                           Concentration of Plutonium in Air - Rocky Flats Site, 1971-1974
                                      - Colorado Department of Health Stations -
Sample Location
On Site
Stations
East of the
Plant

Local (b)
Off Site
Stations


Remote
Station



D-l
D-2
APC-56
D-3
D-4
APC-2
APC-15
APC-16
APC-17
APC-22
APC-29
APC-42
APC-81
APC-108
1971
(fCi/m3-)
0.31
0.34
1.8
10.
7.3
___
0.08
0.08
0.07
0.07
___
	

	
Plutonium Concentration in Air
1972 1973 1974
(fCi/m3) (fCi/m3) (fCi/m3)
1.4
0.69
2.3
4.5
5.5
0.04
0.06
0.06
0.04
	
0.08
0.06
0.07
0.11

0.59
	
.2.9
3.2
0.07
0.05
0.06
0.06
0.05
0.14
0.07
0.23
0.05
0.31
0.72
0.17
3.8
1.3
0.05
0.25
0.08
0.07
0.10
0.07
0.13
0.32
0.14
   Ca)  "USAEC Rocky Flats Plant 1971 Environmental Surveillance Summary Report"
         Colorado Department of Health, Divison of Occupational and Radiological Health, Denver Colorado,  and
         also succeeding volumes in this series through 1974

   (b)   Located in Metropolitan Denver Area; to the east and southeast  of the Rocky Flats Site
to

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 12.   Jefferson County Health Department

      This report states that "less than 10 microcuries of plutonium
 were released from plant stacks and vents to the atmosphere in 1975."
 However,  on one day in 1957, an average of 948 picocuries per cubic
 meter were released from one stack to the atmosphere for a total
 amount of about 5,000 microcuries in one day (3).  In considering the
 rezoning  of agricultural lands adjacent to the plant site for
 residential use, such accidental releases of plutonium in such large
 amounts must be evaluated.

      In the third paragraph on this page, reference is made to figures
 A 1-6 and A 1-7 which show  plutonium values in soils to a depth'of
 five centimeters.  Why was  a more recent report giving plutonium
 concentrations  in respirable dust on the surface of the soil not
 cited,  instead  of this soil inventory figure (8)?  It is noted that
 americium-241 within the site boundaries are about 10% of the
 plutonium-239 values.   In a few decades, the americium will present as
 much radiation  hazard as the plutonium.   I'm not certain that this has
 been considered in calculating the guidelines.

      Staff Response - The most significant releases of plutonium from
 the  Rocky Flats Plant  Site  are still believed to be the result of
 leaking oil drums containing plutonium as a contaminant.  However,
 surveillance measurements cannot distinguish between plutonium from
 stack releases  or from the  leaking oil drums.  In practice,  all
 plutonium in soil around the plant,  regardless  of the source,  has been
 evaluated.

      The  measurement  of plutonium concentrations in respirable dust
 has  not yet been accepted as an  appropriate measurement procedure
 useful  for  the  estimation of hazards associated  with plutonium in soil.

      Americium-241  concentrations  in soil  and other environmental
media were  considered  in the proposed  guidance.

 13.   N.Y  Federation on Safe  Energy

      I would question  why,  at  sites  listed  in the  proposed guidance,
 information is  lacking,  such as  elements  released  to air (pg.  152)  at
Argonne National  Lab.,  and  (pg.  55)  water  at  Oak Ridge  Facilities .
 If EPA wants to  set meaningful guidelines,  Step  One  is  to see  where
you  are now.  This  cannot be done  with speculative  and/or partial
 information.

      Staff Response -  The agency staff believes  that  there is
sufficient information  on environmental  levels of  the transuranium
elements  to permit  the  issuing of Federal Guidance  at this time.
                                       73

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14.  Ilene Younghein

     The Enewetak Islands not  likely  to  be  reoccupied  were  not  named.
p-51 "these high levels are believed  to  have been  caused  by analytical
errors."  Perhaps it would be  wise  to find  out.  p-54,55 finds soil
samples taken at different depths making it hard to  compare.  Why was
plutonium concentrations in water at  White  Oak Creek Clinch River not
published,  (p-46)

     Staff Response - The information given is quoted  from  available
technical reports.  It is relevant  only  to  the extent  that  is provides
an indication of the existing  environmental contamination levels at
various sites.

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 3.2
Annex-II Environmental Transport and Pathways
 1«    Department of Defense

      Department of Energy

      An arrow head is missing between "water" and "sediments."
 IFig. A 2-1).

      Staff Response - Correction to Fig. A 2-1 is acknowledged:

 2.    Department of Energy        '•  ,...,........,.	,..  -..-•    ..... .•.-.•...-._-

      The  implication that environmental plutonium will usually be
 present in oxide form has sometimes been assumed, but without proof.
 References for  these statements  should  be given,   (p.3)

      Staff Response - Price  and  Ames have reported the presence of
 Pu02  under both alkaline  and acidic oxidizing environments.   Their
 observations were made approximately 20 years after  the acidic
 radioactive waste was  disposed to the alkaline soils.  Tamura inferred
 the presence of Pu02  in soils from  the  Nevada Test Site
Theoretical studies by Polzer and Rai and Seme have predicted  PuO,
as the most stable  plutonium compound expected to be present  in soils.

     ref;

     S.M. Price and L.L. Ames, Characterization of Actinide-bearinff
     Sediments Underlying Liquid Waste Disposal Facilities at Hanford
     IAEA-SM-199/87, International Atomic Energy Agency, Vienna  (1975).

     T. Tamura, "Distribution and Characterization of Plutonium  in
     Soils from Nevada Test Site," in The Dynamics of Plutonium  in
     Desert Environment.  NVO-142, USAEC, Las Vegas. Nevada""(1974y."

     W.L.  Polser, "Solubility of Plutonium in Soil/Water Environment "
     ln Procee<*ings of Rocky Flats Symposium on Safety in Plutonium
     Hana£iag_ Facilities,  OWF-710401 rS5"Ch55rcal Company,  Rocky
     Flats Div., Golden,  Colorado (1971).

     D.  Rai and  R.J. Seme,  "Plutonium Activities  in  Soil Solutions
     and the Stability and Formation of  Selected Plutonium Minerals "
     J. Environ. Qual.  6,  p.89  (1971).

-------
3.   Department of Energy

     "In liquid form" is probably intended to mean "as a solution."
(p-3, line 12)

     Staff Response - Wording changed to read "as a solution."

4.   Department of Defense

     Department of Energy

     A 10 um diameter particle does not have an AMAD of comparable
size, thus it is unlikely that particles in this upper range would be
termed respirable.  (p-3)

     A 10 um diameter particle of plutonium oxide will have an
aerodynamic diameter of about 30 um, which is well beyond what is
usually considered the respirable range,  (p-3)

     "wet and dry deposition" should be defined,  (p-3).

     Staff Response - We agree.  The wording of  lines  17-22 should
read:

     Airborne releases of the transuranium elements will generally be
in  the oxide  form and contain a substantial percentage of particles
within the respirable size  range.  Because of  the small gravitational
settling velocities of the  respirable  size particles,  they can be
transported long distances  by air currents before attaching to
surfaces or being removed by precipitation.

5.   Department of Energy

     Unnecessary detail  about Pu02 and hydrated  Pu02 may be
confusing  if  not  further explained,   (p-4)

     Staff Response  -  In future  revisions of  the document, details  of
the interaction of Pu02  with soil particles will be transferred  to
Section 2.2.  Soil Transport in  order to minimize the  confusion of  the
reader.

6.   Department of Energy

      It is implied  that we  can  expect considerable  progress  in  the
understanding of resuspension phenomena  as a  result of recent
 studies.   Actually,  such studies have been conducted for  many years
 and there has been no acceleration of work over the past  several
years, (p-4)
                                    76

-------
     Staff Response - No such  implication  is meant.   It  is  for  this
reason that the agency staff has-selected  to employ,  with some
modification, a relatively simple relationship  for describing
resuspension rather than attempt to  incorporate many  of  the factors
listed in Table A 2-1.

7.   Department of Defense                             .'    _      •

     Department of Energy

     What is depicted in this  table  are not the "factors influencing
wind suspension9' but factors that influence the resuspension of
materials by wind action.  (Table A  2-1)

     A better title would be "Factors Influencing Resuspension  by
Wiad."  "Meteorology," not "Mefcerology."   (Table A 2-1)

     Staff Response - The caption of Table A 2-1 should be  changed to
read "Factors Influencing Resuspension by Mind."

8.   Department of Energy

     The data summarized in this table are of little  value  without
more adequate definition of the terms used and without more
information concerning the circumstances under which  the data were
obtained.  (Table A 2-2)

     Footnotes could easily be mistaken for reference numbers.

     Staff Response - The staff does not agree that the data
summarized in Table A 2-2 are of little value.  Unncessary  details
about experimental conditions would  only confuse the  reader.  As
discussed in the test, the purpose of Table ,A 2-2 is  to provide the
reader with a feeling for the range  of resuspension factors, for newly
deposited material.  Measurements were made under conditions of wind
arid mechanical disturbance. ,            •  ;

9.   Department of Defense.
     Department of Energy

     "over a period of time" is not  clear.  (p-89 line 20)

     The very vague statements about solubiiizatiom of plutonium oxide
should be referenced and placed in some more precise  time frame than
"over a period of time."  (p-8)

-------
      Staff Response - Several  mechanisms have been suggested (see
 references below)  which can lead to increased solubilization of
 plutoniuB after its release to the environment.   Included among these
 are:   1)  chelation by organic  constituents  in the soil  or through the
 addition  of fertilizers,  2) increased root  absorption zone contact as
 plutoniuB migrates down through the soil, 3)  increased  radiocolloid
 size  due  to aging, and 4) the  long-term action of micro-organisms
 present in the  soil.

      Since ouch of the research into these  mechanisms is  in the early
 stages, a quantitative discussion of the time required  for such
 transformations is not currently possible.  However,  preliminary data
 have  not  deaonstrated a rapid  transformation  to  occur under conditions
 generally encountered in the environment.  It is most likely that, if
 these transformations occur at all, they would take on  the order of
 years to  decades.

      ref;

      J.M.  Cleveland and T.F. Rees,  "Investigation of  Solubilization of
      Plutoniun  and Anericium in Soil by Natural  Humis Compounds," Env.
      Sci.  Tech.  10, p.802 (1976).

      E.A.  Bondietti,  S.A.  Reynold,  and  M.H. Shanks, Interaction of
      Plutonium  with Complexing Substances in  Soils and  Natural  Waters,
      IAEA-SM-199/51,  International  AtomTc~EnergyAgency,  Vienna (1975).

      E.M.  Ronney,  H.M.  Mork, and K.H. Larson,  "Persistence of Plutonium
      in Soil, Plants,  and Small Mammals," Health Physics  19, p.487
      (1970).

      W.V.  Lipton and  A.S.  Goldin, "Some Factors  Influencing the Uptake
      of Plutoniura-239 by  Pea Plants," Health  Physics  30,  p.425  (1976).

      K.R.  Price, "A Review of  Transuranium Elements in  Soils, Plants,
      and Animals,"  J.  Envir. Qual.  2, p.62  (1973).

      F.H.F. Au,  W.F.  Beckert,  and J.C.  McFarlane,  Plutonium Uptake
      bya  Soil Microorganism,  Aspercillus Niger,  NERC-LV-539-37,  USEPA,
      Las Vegas,  Nevada (1976 ) ~~"~

 10.   Department  of  Energy

      The relationship between  specific  activity  and oxide  solubility
 should be  stated more  specifically,   (p-9)

      Staff Response - Increased  solubility of Pu-238  versus Pu-239 may
be attributable  to  the  fact that the alpha radiations from Pu-238  are
more  energetic  than those  of Pu-239.  This may contribute  to greater
aggregate  recoil or ejection of  clusters  of atoms  from  the surface of
 the particle.

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11.  Department of Energy

         It is not at all certain that "the resuspension of soil .
particles. .. will be the principal mode of farther environmental-
transport."  It seems more likely .that transport in unvegetated areas
will be by saltation or surface creep, and water movement of -sediments
may be of primary importance in erosion areas.  In heavily vegetated
areas, water transport will probably be of.-. primary importance.  (p-9)

     Staff Response - Mechanisms other than resuspension sr© -also
responsible for the environmental transport of radioactive particles,
and on a mass transport basis are more important than resuspension.
Emphasis was placed on the resuspension of soil' particles 'because
inhalation is generally the most important pathway for environmental
plutonium.  The staff does acknowledge that these other mechanisms
should be discussed and perspective given to  their potential  impacts.

12.  Department of Defense                              '  .
     Department of Energy
     Aqueous Transport ;  Are these four points subjective
determinations by EPA or do they result fro® referenced works?
st.< te.  (p-10)

     The four points listed should be supported by references.

     Staff Response - References:

     Point #1
                                                                 If so,
     J..A. Hetherington,  D.F.  Jerries, M.B.  Lovett,  Radiological
     Impacts of Releases from Nuclear Facilities into Aquatic '-Environ-.
     ments, IAEA-SM- 198/29,  International Atomic Energy Agency,    """"
     Vienna (1975).

     K.C. Pillai  and  E.  Mathew,  Plutonium. in ..... Aquatic_Envirotment8--
     Its Behaviors Distribution,__ai^^gnl!Hca'nc'ea  'lAEA-SM-199/27 ,
     International Atomic Energy Agency, Vienna (1975).

     Point #2  and Point  #3 -            '        .        ,           '    "

     H.D. Livingston  and V.T. Bowen9 .Contrasts Between the Marine and
     Freshwater Biological Interactions of  Plutonium and Americium,
     HASL-315, Health and Safety Laboratory, USERDA, p.I-157 (1977).

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13.
Point #4

V.T. Bowen, H.D. Livingston, and J.C. Burke, Distribution of
Transuranium Nuclides in Sediment and Biota of the North Atlantic
Ocean, IAEA-SM-199/96, International Atomic Energy Agency,
Vienna (1975).

Department of Energy

"Concentration factor" requires definition  (p-10, line 22).

Staff Response - Concentration Factor
                                             pCi/kg (wet plant)
                                               pCi/kg (water)
14.  Department of Energy
     The reference to Langham's "studies" at Thule is in error.  There
is no mention of Thule in this paper,  (p-10)

     Staff Response - Reference to Langhara: USAF Nuclear Safety 65,
p.36 (1970).

15.  Department of Energy

     The postulated "limited mobility for environmental transport" in
aqueous systems does not take into consideration extensive data on
transport of sediments bearing radioactive materials in the Tennessee
and Columbia Rivers.  Movement of plutonium on sediments has also been
demonstrated in several estuaries,  (p-11)

     Staff Response - The staff agrees that the wording should be
changed to reflect the fact that hydrological transport of plutonium
contaminated sediments occurs in marine and freshwater ecosystems and
has been responsible for transporting radioactive material as much as
several miles from its point of initial release.  Since the
radioactivity is primarily associated with the bottom sediments, its
radiological significance in terms of dose to man has been generally
assessed to be small.  As long as the water body is maintained at a
fairly constant level and large areas of the sediment bed are not
exposed and allowed to dry, thereby becoming a wind resuspension
problem, the radioactivity committed to the water will be bound in a
form which has little biological availability.
                                      eo

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     Department of Defense
     Department of Energy

     The PAID code is crucial to  the derivation  of  the  guidance,  yet
it is not published.  Because of  the complexity  of  aerosol  physics,
particle sizes and distributions, etc.,  it  is  really  unfair to  ask
that the general radiation industry accept  on  faith the assumptions,
parameters and other input used in the PAID code; it  should be
available for review,  (p-12)

     No description of the PAID code is  given  here, or  in Annex III,
and the only reference is to an unpublished document.   Since the
specific numerical basis for this Guidance  is  all derived from  the
PAID code, its unavailability prevents any  verification of  these
numbers,  (p.12)

     Staff Response - The PAID code is available as:  Plutonium Air
Inhalation Dose (PAID), Technical Note ORP/CSD-77-4,  USEPA,  Office of
Radiation Programs, Washington, D.C.

17.  Department of Energy                         ••''.-

     It is implied that because the PAID code  "assumes  Og to be 1.5,"
it is never necessary to determine <^ .   Since  measurement of AMAD
provides the data required, 
-------
      3.   the  limited  size  distribution data obtained in the  vicinity
of plutonium  contaminated  areas  have  been able to be fitted  reasonably
well  by a log-normal  distribution..

      ref;

      M.W.  Nathans, W.D. Holland,  and  H.C.  Shaw,  The  Size Distribution
      and  Plutonium Concentration of Particles  From the  Rocky Flats
      Area, TLW-6111,  Trapelo/West, Division of LFE Corporation.
      Richmond, Calif.  (1971).

      L.R. Anspaugh and P.L. Phelps, "Results and Data Analysis:
      Resuspension Element  Status  Report"  in The  Dynamics of  Plutonium
      in Desert Environments, NVO-142,  USAEC, Nevada  Operation Office,
      p. 265 (1974).
18.  Department of Energy                             '•

     This is a confusing paragraph  that  should be  revised or deleted.
It is not made clear why the entire distribution need be measured, nor
how it is possible to do this  if all  samplers have an "upper size
cut-off."  The reference to "resuspending soil" is confusing in this
paragraph which is otherwise devoted  to measurements in air.
(p-13, line 14)
     Staff Response - The reason for this admonition is the  fact  that
most lung models in general use assume that the value of the ambient
air activity (which is supplied as input to the particular model) is
the total air concentration.  These models then proceed to fractionate
the total concentration among the various lung compartments.  In  order
to be consistent with this assumption, measurement should encompass
the widest range of particle sizes possible.  The interested reader is
referred to the following reference comparing the collection
efficiencies of several commonly used methods.

ref: Wedding, J. B., McFarland, A. R., and Cermak, J. E., "Large
Particle Collection Characteristics of Ambient Aerosol Samples", Env.
Sci. and Tech., 11, p. 387 (1977).                               	
19.  Department of Energy

     This is an over simplified interpretation of a very limited
experiment.  The field was small and the range of meteorological
conditions limited.  Sweeping conclusions based on this single
experiment are hardly justified.

-------
 However, much higher exposures would have been  inferred  had  EPA
 employed the data collected at 7.6 m from the edge  of  the  field rather
 than utilizing the data collected at 30 m from  the  edge  of the  field.
 It is not necessarily true that an individual might not  spend a great
 deal of time at the edge of the field, since farmhouses  are  often  at
 the edges of fields.                                             :.
 (p-14, line 14)

      Surrounding areas downwind would be expected to experience  some
 increased exposure due to "these operations."  The  Guidance  contains
 numerous sentences in which the word "significant"  is employed without
 definition.  (p-14, lines 20-21)

      Staff Response - Ideally one would like to have more  data
 encompassing other types of soils and different meteorological
 conditions before attempting a scoping calculation  of this kind.
 However,  there is a paucity of such data.  This calculation was meant
 to put into perspective the relative impacts of wind versus mechanical
 disturbance of a  field with surface contamination roughly
 corresponding to  the screening level suggested in this Guidance.  The
 air data  reported for 7.6 meters  from the edge of the field was not
 incorporated into the calculation because the authors had raised
 doubts as  to the  precision of  that data:  "the large means and standard
 deviations...for  the sampler  locations  7.6 m downwind from the edge of
 the field were  caused by 3 high measurements out of 27."
                                   «*
     Using  the  same  data,  Healy  (ref. 37) has also attempted  to
 analyze the  impact of agricultural operations.   His  objective was to
 calculate  the maximum soil  concentration  that would  not exceed a
 skeletal dose rate of 500 mrem/yr  after  70 years to  an  individual at
 the edge of  a contaminated  field.  He concluded  that 14 uCi/m2 would
 be  the maximum allowable concentration for a 1000 m  wide  field if
 plowing were performed 40 hr/year.  Extrapolation of Healy's  data to a
 field  at the screening level of 0.26 uCi/m2  results  in  a  projected
 dose rate of 9.2 mrem/yr after 70 years or 0.5 rarad/yr  (based on ICRP
 Publication #26).  This dose rate  is a small fraction of  the  3 mrad/yr
 limit  recommended in  this Guidance and, therefore, would  not  present a
 serious risk to individuals in the vicinity  of the field.
20.  Department of Defense
     Department^ of Energy
     A subjective conclusion that cannot be supported.  If a one-time
cultivation results in a many-fold increase inhalation hazard, one
could just as easily conclude that the second-time disturbance could
also cause an increase,  (p-14, line 18)                !,

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                                    10
     If the first cultivation cycle resulted in a  30-fold  increase  in
air activity, it appears questionable  to conclude  that  subsequent
cultivation "should not lead to  significant increases."
(p-14, line 18)

     Staff Response - The document did not conclude "that  a one-time
cultivation results in a many-fold increase in inhalation  hazard."
The analysis showed that, although the air concentration increased
during the various agricultural  operations, the yearly  average
concentration was increased by less than a factor  of 2  for the  tractor
operator (over that from wind resuspension) and by only 10% at  a
location 30 meters downwind from the edge of the field.

21.  Department of Energy

     Assuming the maximum indicated resuspension fraction  of  10~2,
passage of 100 cars would leave  37% of the original contamination on
the road surface.  Is this "a small fraction?"  (p-15,  line 3)

     Staff Response - The conclusion that only a small  fraction would
remain after the passage of 100  cars was taken from the original paper
of G.A. Sehmel.  That conclusion, however, does seem to be an
overstatement by the author.

22.  Department of Defense
     Department of Energy

     Distinguish between "uptake" and "uptake factor" throughout the
section.  Is one actual amount and the other a percent  of  that
available or what?  (p-16)

     Throughout Section 3.2 the  words "uptake" and "uptake factor"  are
employed in an ambiguous manner.  They should be replaced  by  more
precise and carefully defined terms,  (p.16)

     Staff Response - "Uptake" refers to the amount of  transuranium
material retained within the plant or animal.
     "Uptake Factor"
                       pCi/g acceptor
                       pCi/g donor
23.  Department of Energy
     The assumption that "foods from other areas not as highly
contaminated will make up part of the diet" might not be true of a
"critical segment" of small farmers and home gardeners.
(p-17, lines 1-3)

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                                   11
     Staff Response - The assumption that "food from other areas not
as highly contaminated will make up part of the diet" was applied only
to estimating annual intakes for the general population.  It is true
that farmers and home gardeners who raise crops for their own
consumption on contaminated land may have higher annual intakes than
the general population and would have to be considered as a "critical
segment" of the population when applying this Guidance.

24.  Department of Energy

     It should be clarified that 1.6 pCi and 2.6 pCi are estimates of
fallout plutonium absorbed from the gastrointestinal tract into the
blood.  The word "intake" might be misinterpreted as "ingestion."
(p-17, line 5)

     Staff Response - The above DOE statement is incorrect.  According
to ref. 28, "the annual intake during 1972 was 1.6 pCi, due to 35% to
grain products, 20% each to vegetables, fruits, and meats, and less
than 4% to dairy products.  The annual intake in 1965 was estimated to
be 2.6 pCi".

25.  Department of Energy
     The "extreme assumptions of soil consumption rates...required"
should be defined.  Pica in children is characterized by  "extreme"
behavior, as discussed at some length in ref. 37 of this  Annex.  Might
these children not qualify as a "critical segment?"  The  importance of
a more precise definition, in the Summary Report, of "critical segment
of the exposed popluation" is emphasised by questions such as this.
(p-17, lines 23-25)

     Staff Response - Pica in children iis not normal behavior and
would persist for a relatively brief period of time.  Such isolated
cases do not constitute a "critical segment" of the population.

     The intent of the Guidance is to limit the risk from chronic
exposure to the transuranics to an acceptable level.  In, the case of
ingestion9 the limit is expressed as the 70 year bone dose rate of
3 mrad/yr.  Although acute exposures can always be postulated,which
exceed the normal chronic exposure levels, these must be  analyzed in
terms of the projected 70 year bone dose rate.  If such  projections do
exceed the 3 mrad/yr (70 year), then the intent of the Guidance
is that remedial action should be taken.

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                                    12
 26.   Department of Energy

      The reference to "short residence time of plutonium in the
 gastrointestinal tract" is confusing and should be deleted, since
 radiation dose to the tract from alpha emitters is not considered
 significant,   (p-18,  line 1)

      Staff Response - Sentence changed to read:  "However,  for the
 pathway to be as significant as the inhalation pathway,  extreme
 assuaptions of soil consumption rates would be required.  This is
 because of the low transfer of plutonium across the gastrointestinal
 tract and the radiation dose to the tract from alpha emitters  is  not
 considered significant."

 27.   Department of Energy

      This sentence seems to'say that a resuspension factor, .based on
 repeated Measurements over a long period of time,  can be  used  to
 calculate concentrations in air from concentrations in soil.   But if
 one has  already measured the concentration in  air  in order  to  derive
 the resuspension factor, why would it be necessary to calculate a
 concentration in air?  (p-19,  line 7)

      Rather than "areas" this  sentence should  refer to "points,"
 since,  by definition,  the resuspension factor  is based on a
measurement in air and soil at one point.   In  addition to the
 "variability  of the local meteorology," reference  should  also  be  made
 to variability in mechanical  disturbance.

      Staff  Response -  Oftentimes  in assessing  the  potential hazard of
existing contamination,  resuspension data  are  available for several
 locations  on  a particular site.    However,  data will  not  exist  for
every point.   The  sentence in  question refers  to using such
measurements  in evaluating the  locations on the site  for  which  air
data  are not  available.   Whenever  air measurements  exist  they  are
certainly preferred over any calculational  relationship between air<
and soil.   On the  other  hand,  the Agency feels  that  it would not be  in
the interest  of public health  protection to postpone  a decision on the
necessity of  cleanup because air measurements at every point are not
available.

28.  Department of Defense          .                    -
     Department of Energy

     C.F. needs better definition particularly  as  to  how  it is
influenced by the depth of sampling  and soil density,  (p-19,  line 2)
                                     86

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                                   13
     This equation cannot be properly understood unless CvF.  is better
defined.  An explanation should be given for the effect of  depth  of
sampling and soil density,, and how these effects are applied  in. C.F.-
(p-19, line 19)

     Staff Response - C.F. is the factor which converts, a soil
concentration in units of activity/surface  area  to  units  of
activity/weight of soil.  This is accomplished through  the  use of the
sampling depth and average soil density:
activity    x 	1	 x        1
surface area   sampling  depth    soil  density

29.  Department of Energy
  activity
weight of soil
    v It would .be helpfui  to  briefly .mention .the. methods by which -
airborne particles  are measured in the National Air.-.Surveillance
Network  (e.g., height of  measurement).  Without such a description,, it
is not clear whether or not. these measurements have any relevance to
the  problem of transuranic  inhalation.  (p20, line 1).

     Staff  Response - Specific details as to methods of particle
collection  employed in  the  National Air Surveillance Networks are
described in Fed. Reg.  36:22384-22385 (1971).  Regarding the question.
of sampling height, no  specific guidance is given as to the location
of samplers.   It must be  assumed, therefore, that the data reported by
the  NASN is a  composite of various sampling heights.

30.  Department  of  Energy                         '

     This  sentences even  with the explanation that, follows,, is not-
clear.   (p-20,  lines  10-14)              t

     The sentence  beginning "This fallacy" would seem-to suggest ,that.-
there  is only  one  fallacy involved in the mass loading approach.to
resuspensiori.  Not  included is any discussion of the usually erroneous
assumption that  the particles measured in the air come from the
contaminated  area.   This  is least apt to be  true for the most
 important  (respirable)  fraction,  (p-20  line  10)

      The derivation of the Enrichment Factor  is :presented here with no
 discussion of its  theoretical inadequacies and its 'lack of    ^  .
 experimental  verification.  Since there.is no 'experimental  supports
 for the applicability of this •"Enrichment Factor,"'1 and since the
 correction .which it introduces is .small <• compared to other    .   _

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                                    14
 uncertainties in resupension estimation,, and since it introduces
 costly implementation problems, the Enrichment Factor should be
 abandoned,  (p-26, line 17)

      If retained, the assumptions implicit in the Enrichment Factor
 should be stated.  These are:  (1) All of the smaller particle sizes
 in the soil are resuspended with equal probability; (2) all of the
 soil particles in the air sample arise from the contaminated area.
 The last particles, once airborne, are fractionated in size by
 deposition and that the smaller particles can travel hundreds or
 thousands of miles,  (p-26 line 17)

      The "equilibrium" implied is more correctly stated as one in
 which the amount of material in each size range deposited should equal
 the amount of material in each size range resuspended over the area.
 Both deposition and resuspension rates change as a complex function of
 particle size and wind speed,  (p-29,  line 7-10)

      The comparison made in this sentence is  not a valid one, because
 the factor estimated from Equation 8 is in reality a soil resuspension
 factor,  while those to which it is compared are radioactivity
 resuspension factors.   It is one of the inadequacies of the mass
 loading  approach that  these two kinds  of factors not directly
 comparable.

 Department of Defense

      Enrichment Factor:   The enrichment factor section suffers from a
 lack of  discussion on  its shortcomings, the assumptions  in it, and
 absence  of experimental  verification.   Its desirability  or utility is
 not established,   (p-26)

      Staff Response -  The above comments  seem to reflect  a basic
misunderstanding on the  part of DOE  and DOD regarding  EPA's  use of the
mass  loading approach  and the enrichment  factor.   The  agency staff
wholeheartedly agrees  with DOE and DOD fractionation of particle  sizes
occurs with  resuspension.   Particles in the small  or respirable size
range will be  more  susceptible to  resuspension and will remain
airborne  longer  than the  larger diameter  particles.  This
fractionation  process  will generate a  distribution of  airborne
particles  different  from  the distribution  of  the bulk  soil  and,
therefore, the activity per  weight of  the  suspended  dust will  be
different, from the  activity  per weight  in  the  bulk soil.  Depending  on
the way in which  the activity is distributed  across  the size  range of
the bulk soil,  there will  either be an  enrichment  of activity  per
weight in  the  suspended dust  or a  reduction of  the activity per
weight.
                                  88

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                                   15
If the activity is predominately associated with the smaller, more
resuspendable soil particles, the suspended dust will have a higher
activity per weight than the bulk soil and vice versa.  In any  case,
it is unlikely that the activity per weight in the airborne material
would be the same as that in the bulk soil.

     The mass loading approach by itself  is not capable of considering
this fractionation effect and as such would predict the same activity
per weight for suspended and bulk soil.   Because of this, the agency
staff has developed what it terms an "enrichment factor."  The  purpose
of this factor is to modify the basic mass  loading formula in such  a
way as to reflect the distribution of activity as a function of
particle size and the differences in size distributions between the
bulk soil and suspended dust.

     Another point of confusion appears  to  be the context  in which  the
mass loading and enrichment factor were  applied  in the Guidance. This
calculational technique was used  in  the  derivation of  the  soil
screening level.  The agency  staff feels that this level  is
sufficiently low that costly monitoring  of  the  inhalation  exposure  is
not required when surface concentrations are  at  or below  this value.
In order to derive such a number  on  a generic basis and  to  insure that
this level  is safe,  some conservative assumptions had  to  be made,
e.g.,  it was assumed  that the  contaminated  area  was  sufficiently large
enough that the airborne mass  loading could be attributed to  the
resuspension of soil  from the  contaminated  area.  The  staff  does not
dispute the point raised by DOE  that, at real sites,  injection of
suspended particles  from noncontaminated areas can  contribute  to tht-
mass  loading.   If injection of these particles is  occurring,  then th2
mass  loading calculation would predict  higher than  actual airborne
activity thereby, overestimating the inhalation exposure.   For this
reason, the Guidance recommends  the  use of site-specific data to
assess the  actual exposure  hazard when  soil concentrations exceed the
screening  level.

 31.   Department of  Energy

      The  data  of  Table A 2-3 are not the only data,  nor the most
applicable  data.   Recent  studies of Sehmel (ref. 39)  show much poorer
 correlation between predicted and observed results,   (p-20, lines 8-^10)

      Refernces to Anspaugh are incorrectly listed.   (Table A 2-3)

      More recent and more applicable data of Sehmel (ref. 39)  should
 be presented if this data is to be used.  (Table A 2-3)

      The mass loading approach is said  to be supported by references
 30 and 31.   It should also be stated that more recent studies  (ref.
 39) have not supported the mass loading  approach,  (p-26, lines  4-8)

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                                    16
      Staff Response - From the above comments, it appears that the DOE
 staff attribute considerable importance to ref. 39 and its conclusion
 that the mass loading approach is not a viable predictive methodology.
 Because DOE relies so heavily upon this reference, it is necessary to
 point out some of the limitations and serious errors contained in that
 reference.

      First of all, as the author points out "Caution should be used in
 interpreting these data.  The ground surface contamination data are
 limited in quantity and were not necessarily obtained in the same
 areas where resuspension experiments were performed."

      In addition to the uncertainties raised by the above statement,
 the  EPA staff questions the way in which the author interpreted his
 data.  The approach used was to make comparisons only on the basis of
 extreme upper or lower observed limits.   No attempt was made to define
 an "average" case (e.g..,« the mean observed concentration) and make.
 comparisons accordingly.  The mass loading approach has been used in
 the  past only to calculate annual average air concentrations and was
 used by EPA only in that context.

      More importantly,  the author's conclusion that the mass loading
 approach did not predict the observed air concentrations was based
 upon an apparently erroneous calculation.   It appears that the
 calculated values in Table 6 of ref.  39  are in error  by 6 orders of
magnitude because units  were not  matched properly.  As  a~~resultY the
predicted values in Table 6 are too high.   When the necessary
correction is  applied,  the predicted and observed  levels show better
correlation.   For the lower limit case of 27.73 ug/m3,  the total
concentration  (Pu-239)  of respirable and nonrespirable  particles  is
calculated to  be 1.9xlO~17 uCi/cm3.   This  calculated  value can be
compared to  the  observed mean value of roughly 2x10"^^  uCi/cm3
 (Figure 6 of ref.  39)  or the lower observed limit of  approximately
5xlO~18 uCi/cm3.   Whether the sampling of  the lower limit Pu-239
concentration  coincided  with the  recording of the 27.73  ug/m3 is
impossible to  say from  the data as  presented.   However,  it  can be
justifiably  argued that,  within the  limitations  of  the  data,  correct
interpretation should have yielded  the opposite  conclusion.

32.  Department  of Energy
     Department  of Defense

     No evidence has been presented  to support  the  conclusion  reached
in this sentence  that this approach "would  seem reasonable."   It
easily could be  argued that  the reverse  is  true.

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                                   17
The aged source could contain a greater proportion of  the  transuranics
at greater depths in the soil profile and the resuspended  surface
layer presumed to constitute the particle loading of the air  would
less accurately reflect average soil content,   (p-20,  line 24)

     Why does it "seem reasonable"  that the error associated  with
using mass loading approach would be least in "old" soils. With time,
it might seem reasonable that there are more transuranic elements at
depths than at the surface, thus causing the reverse of what  is
depicted here,  (p-20, last sentence)

     Staff Response - The  statement in question is based on the  fact
that plutonium after it has been in the environment for a  period of
time has generally been found to be associated  with soil particles,
rather than existing as discrete plutonium particles.  This
association is the result  of various chemical and physical processes
which are collectively .termed "weathering."  Once;it  is'associated    r
with the soil particles, the plutonium would be expected  to resuspend
in the same manner as the  surface  soil and, therefore,its  resuspension
can be related to the airborne  dust loading.  On the  other hand,
freshly deposited activity may  be  more easily resuspended  compared  to
the bulk soil due to a higher percentage of plutonium particles  in  the
smaller size ranges.  The  decrease in  the  resuspension with time of
freshly deposited material is generally attributed  to  weathering.

     The observation by DOE and DOD that  there  may  be  more activity:at
greater depths with the passing of time  is not  germane to  the
discussion.  The Guidance  considers the erodible surface  to be the  top
one centimeter and relates only activity within that  centimeter  to  the
airborne concentration.

33.  Department of Energy

     It is  incorrect  to  state  that the  resuspension rate  approaches
have "attempted  to include in  their formulations as parameters some of
the physical  forces which  control  the  resuspension  phenomenon."  The
Healy-Fuquay approach  (ref.  32) to defining  the rate  was  used because
of  the  lack of empirical  data  at  that  time.   Present  emphasis should
be  placed  on  the more  recent  considerations,  presented in ref. 37.
(p-23,  lines  7-9).

     It might be  noted  that more  recent  calculations by Healy in-ref.
37  did  include variations  in resuspension rate  with wind  speed.,
(p-24,  lines  5-7)

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                                     18
 Staff Response - The Healy-Fuquay approach  (ref.  32)  assumed  that  the
 rate of pickup of particles  from a  surface  is  directly  proportional  to
 the ratio of wind forces  to  gravity forces  on  individual particles.
 By taking the wind force  on  a particle  to be proportional  to  the
 square of the wind velocity  and the particle area exposed  to  the wind,
 an expression was developed  for the rate of particle  pickup.

 34.  Department of Energy

      This sentence implies that there are formulations  for predicting
 resuspension that have "general applicability."  Actually, none have
 been demonstrated to have any "general applicability."
 (p-24, lines 21-24)

      Staff Response

      No such implication is meant and in fact the text clearly states
 "the general applicability of these formulations...has not been
 demonstrated."

 35.   Department of Energy

      Some qualification is needed  of the statement that the weight
 fraction of  particles   10 urn is  small  in most  soils.   The tabulation
 of published data in reference 37  shows  that this fraction ranges  from
 a  few percent in  sands  to several  tens of percents in loams.   Perhaps
 undisturbed  soil  including aggregates  is meant.  Even here care must
 be taken  because  soils  lose their  texture under long  drought:
 conditions,   (p-27  lines  2-4)

      Staff Response - The basis  for  the  statement in  the text  was  data
 from  sites of existing  plutonium contamination  where  the less  than
 10 urn weight fraction has been small.  In certain soils, especially
 clays, this  fraction can  be larger.

 36.  Department of Energy

     Methods  for  the analysis of particles within size ranges  should
be described  or referenced,   (p-27,  lines  22-25)

     Staff Response - Various methods  of particle size fractionation
are described in the technical literature.   Since detailed
implementation of the Guidance is left up to the responsible agencies,
it is not appropriate to present such  details lest it  be misunderstood
as the only acceptable method.

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                                    19
37.  Department of Energy                                 .

     Subscript "i" misplaced,   p-28,  line  19)

     Subscript "i" misplaced.   (p-29,  line 1)

     Staff Response - Typographical errors are  noted.

38.  Department of Energy_

     The parenthetical  expression, "based  upon  certain assumptions
regarding prevailing meteorology," seems inadequate  to convey the
factual information that the  calculations  employed annual wind roses
with joint wind speed,  direction, and stability,   (p-29,  lines 24-25)

     Staff Response - Such  details were not felt  to  be necessary.
However, future revision will  reflect this comment.

39.  Department of Energy

     An additional  important  assumption, not listed, is the assumption
that ingestion is a neligible risk compared with  inhalation.  This
sometimes questionable  assumption may compromise  the utility of the
.screening level concept.  There would seem'to be  no  reason  why
ingestion could not be  considered as  an additional factor in the
derivation of and probably  accommodated in the  screening level, thus
making it more a universally  applicable concept.   (p-30,  lines 10-17)

     Staff Response - Assessments of  dose  to populations  surrounding
transuranium contaminated  locations  in the U.S. have concluded that
the principal exposure  hazard is inhalation and that the ingestion
pathway is of little consequence.  For this reason,  the agency staff
derived the  soil screening  level on  the basis of  the inhalation
pathway as being the limiting case.   It  is possible in the  event of
some future  accident that  the ingestion pathway could be of greater
significance.  However  the  staff did  not  consider it appropriate to
derive the screening level  for soil based  upon  a  future occurrence at
some hypothetical  location.  The wide variation possible in crops
types  and dietary habits makes such a generic derivation tenuous.

     On the  other hand, the agency  staff has looked at the  impact of
the ingestion pathway .on populations  with  various .postulated dietary
habits who are exposed  to. land contaminated at  the screening level. ..
Even for the situation  of  the serious home gardener, the dose rates
are not projected  to exceed the limits recommended in this  Guidance.

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                                    20
 40.   Department of Energy

      The  value of 100 ug/ra^ needs to be more carefully evaluated and
 the  exact context of Anspaugh's and Healy's use of this number
 described,   (p-30, lines 21-25)

      Staff Response - Anspaugh employed a value of 100 ug/m3 for the
 airborne  mass  loading when calculating acceptable soil concentration
 applicable to  the Enewetak Atoll.  His choice of 100 ug/m3 was based
 upon an evaluation of values reported at rural sites in the
 continental U.S.  and Hawaii.  Anspaugh concluded "this value should be
 quite conservative for the Enewetak Islands and, therefore, allows
 rooa for  the uncertainty involved because the people themselves may
 generate  a significant fraction of the total aerosol."

      Healy concluded that a value of 120 ug/m3 was sufficiently
 conservative in calculating limiting soil concentrations by the mass
 loading approach.   His choice  was based simply upon an interpretation
 of EPA18  standard for airborne particulates .

 ^ *   Department of Energy

      Additional justification  is required for the use, as an average
 distribution over a 1-year period,  of data measured by Chepil in a
 dust  storm,  (p-31,  lines 4-6)

      Staff  Response - Regretably there is a lack of particle size
 distribution data covering the entire range of suspended sizes.
 Primary emphasis  has been placed on the measurement and control  of
 saall particles (  5 urn)  because possible deleterious effects can be
 better correlated  with the smaller  sizes and because these sizes are
 responsible  for light scattering and visibility reduction.   Few
 researches  have reported data  for the larger particle sizes.   An
 effort was made in the text  to compare Chepil's data with other
 sources and, within the  limitations of the  data,  there was  reasonable
 agreement.

 42.   Department of Energy

      It is misleading to quote Sehmel'a data as indicating "28%  of the
mass  was below  10  urn", when, in fact,  23% was  the maximum value
measured, under minimum  resuspension conditions,  and a value  of  0.3%
was measured for  the  greatest  mass  loading,  during  dust 'storm
conditions.  If use  is  to  be made of this data it  should  not  be  used
 selectively,  (p-31,  lines  11-13)

      Staff Response  - The  data selected from Sehmel's  report  was  that
which  corresponded most  closely with annual  average mass  loadings
reported by  the National Air Surveillance Network.

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43.  Department of Energy .                 ...

   -  Figure is not clearly titled or labeled,-and  it  is  not-
referenced. (p-32, Fig. A 2-3)

     Staff Response -•• Figure A 2-3  is referenced and  discussed on
page 11-31.

44.  Department of Energy

     The acceptable air concentration here  employed for  derivation of
the screening level is based on  an  assumed  AMAD'of 1  USB.  In Annex V
(p. 6), "the Agency suggests that such  a derived air  concentration
limit be based on an  activity median aerodynamic particle diameter
(AMAD) not to exceed  0.1 urn."  This apparent  discrepancy should be
explained  or eliminated.  A reference at this point ,to the discussion
in Annex V would seem appropriate.   (p-339  lines 5-8)         '   ..<•».•••

     Staff Response - There is no discrepancy in using a 1 urn AMAB in
calculating the soil  screening level and use  of 0.1 urn AMAD for the
air screening level.

     In situations where contaminated  soil  is the  primary source of
the airborne activity, AMAD's of approximately 1 urn have been
reported.  Whereas, when stack release  are the primary source, auch
smaller AMAD's  (approximately 0.1  urn) have been observed.  In deriving
the soil  screening  level, which  relates the airborne activity to the
soil as the  source, a 1 um AMAD  was used.  On the  other hand, in
defining  an  air  screening  level  where  the source is unspecified the
more conservative assumption  of  a 0.1  urn AMAD was  used.

45.  Department  of  Energy            '   '"'".'•..

     This Table  requires  a title and a reference and should presumably
be A 2-4.

     It  is not  clear  what  these  data represent.  Are RF  1A, IB and  1C
aliquots  of  a  single  sample?   What area is represented by  these
 samples?   How were  the sizes  determined?  Do they  include  aggregates?
What was  the season of the year  and the moisture content when
 sampled?   Can the results  be reproduced if another sample  is  taken?
These  questions are all important  if the data are  to be  understood.
 (p-34, Table A 2-3)

      Staff Response - Table A 2-3  on page 11-34 should  be  renumbered
 as Table A 2-4.

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                                     22
       Reference for Table A 2-4 is:  D.E. Bernhardt, Evaluation of
  Sample Collection and Analysis Techniques for Environmental Plutonium
  ORP/LV-76-5,  USEPA, Las Vegas, Nevada.         ~~~	~	:
       Specific details of the sampling and analysis methodologies are
  described  on  pages  20 through 45 of the above reference.

  46.   Department  of  Energy

       If resuspension  values  have been reported  for "existing sites"  it
  would seem important  to  list and reference  them in the Annex.  Are
  these annual  average  factors or  single measurements?  (p-35,  lines 6-7)

      .Staff Response - Anspaugh (ref.  30)  reported  resuspension factors
  of 3x10 "nfA  and 2xlO-9m-l as a  result of 17 months
  of measurements at the Nevada Test  Site.

  m-9 R?dgers  (ref' 4) reported a  resuspension factor of approximately
 10 *m A for the vicinity of Mound Laboratory based upon 3 years of
 data.                                                     *

»      Healy (ref.  37) calculated a resuspension factor of 2xlO~9m~1
 for the Rocky Flats Plant site based upon 4 years of reported data.

 47.  Jefferson County Health Department

      Environmental transport and  pathways.  On page 4,  reference  is
made  to  the work  of Tamura,  who has shown that plutonium bound to fine
particles  (2-5 microns)  was  present as hydrated plutonium oxide.  Is
hydrated plutonium oxide more likely to be taken up from the
intestional tract?   I  note in the last paragraph on this  page that
  such a wide range  of  values  makes prediction  of the resuspension
factor for  a particular  set  of conditions  a  difficult task."  The
guidance implies  here  that there  is  a variation  of  perhaps  100
Elsewhere in the  EPA guidance, a  variation factor of one million  is
cited.  This order of  variation makes the  use  of such a resuspension
factor questionable.

      Staff Response -  Hydrated plutonium oxide is not more  likely  to
be  taken up from  the intestional  tract.  For example.  Pu(OH)A has
been  reported  to have  a solubility constant of 7xlO~56 which \s
indicative of  a high degree of insolubility.

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                                   23
     The staff did not make use of the resuspension factor approach in
developing its guidance levels because of the wide variation in
reported resuspension factors.  The range which is quoted as 10
covers virtually all reported values for the resuspension factor
regardless of the experimental conditions.  Many of these were
obtained under conditions not applicable to environmental conditions.
When these values are removed from the data set, a narrower range  of
values is obtained.  The resultant range is still too  large, however,
to be useful  in developing a generic resuspension factor.

48.  Jefferson County Health Department

     Soil transport  (page 8).  This report  states that plutonium
dispersed on  the  soil "has a  tendency  to bond  chemically and/or
physically with the  soil."  Why  then did the plutonium become  airborne
from the  soil containing plutonium in  cutting  oil at  the plant site?
The  report further notes that plutonium oxide  is  "generally considered
to be  insoluble?', but  "can undergo dissolution in neutral aqueous
media."   The  plutonium oxide  particle  dissolves producing plutonium
ions until the  formation of  a hydrated coating inhibits further
dissolution."  "Plutonium  ions  formed  during the dissolution can
undergo  ion  exchange reactions  with the oxygenated  ligands commonly
found  in soil (e.g.  silicates),  and become sorbed onto the soil, or^
react  with  other  agents present in the aqueous phase and form soluble
complexes."   Since  plutonium ions are  able to displace most cations
 such as  calcium,  magnesium,  sodium, etc.,  it would seem that such
plutonium compounds would be available for uptake by plants.  The
ability of seaweed to concentrate plutonium with a concentration
 factor of about 1,000 is noted on page 10.  Algae also have this
 ability.

      Staff Response - The plutonium did not become airborne from  the
 soil but along with the soil as a result of soil resuspension  due  to
 wind erosion and mechanical disturbance.

      Plutonium ions have been found to bond strongly  with  the  soil
 matrix through the displacement of other cations.  This  tendency  to
 bond with the soil matrix is one  reason for the slow  migration of
 plutonium through soil and its  low uptake  by  plants.

 49,  Jefferson County  Health Department

      The section on  inhalation  notes  on page  13  that  "when the aerosol
 being sampled contains large particles of  activity associated with
 them  the gross  air  activity being measured may be  underestimated  and
 "if particles  from  the resuspending  soil  have disproportionate amount
 of  activity associated with  them, the inhalation hazard could be
 underestimated."

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                                    24
      Staff  Response - The above statement was taken out of context.
 It  refers to  the  fact that air sampling,  in order to be compatible
 with  the mathematical models  describing lung deposition, must be
 operated to collect the  widest range of particle sizes possible.50.
 Jefferson County  Health  Department

      Enrichment factor (page  26).   In reference to the use of
 respirable  dust samples, the  report states at the top of page 27,  that
 "however, the weight fraction of -particles in the less than the micron
 range is small in most soils, and  sampling, separation, and analysis
 techniques  are correspondingly more difficult and inaccurate."  .This
 is  incorrect, since we found  that  this fraction can constitute as  much
 as  62% of surficial soil.   This sampling  and separation procedure  was
 developed with the  assistance of soil scientists with doctoral
 preparation in this area (8,9). As the guidelines acknowledge, the
 hazard presented  by plutonium oxide in soils is primarily due to
 inhalation.   To use other than a respirable surface dust sample will
 give  misleadingly low values.  It  is not  possible to relate in any
 consistent  manner the proportion of the respirable fraction to the
 surface soil. This is understandable, since the proportion of
 windblown material  retained at any specific site will depend upon
 topography, vegetation,  the strength of prevailing winds and many
 other factors.  The best way  to evaluate  the hazard is by use of a
 surface respirable  dust  sample, which will provide consistent results
 from  season to season and site to  site.   Calculations based on the
 questionable  assumptions used in this and other sectins have little
 value, in my  opinion.

      Staff  Response - The  chemical analysis used by Dr. Johnson in
 soil  sampling was purposely designed to destroy the cementing agents
 and grain coatings  that  bind  small particles into microaggregetes,
 thereby altering  the  form in  which they actually exist in the
 environment.  A detailed  critique of Dr. Johnson's proposed respirable
 size  sampling method  is  contained  in Chapter 7  of this document. ,

 51. Representative  Timothy Wirth              ,               .     . ]   '

      I think  that the  enhancement  factor  approach that was used to
 correct the "mass loading" assumption will tend to make the results
more  valid, but it  seems  to me that more  research needs to be done on
 this  problem.  Not  only  the "mass  loading" approach an equilibrium
 approach — which may  need to be corrected for  nonequilibrium effects
 in order to become  a more  realistic model  —but the  entire issue  of
 respirable  particulates,  and  the weight that should be given to them,
must be dealt with  better  as  well.   This  implies no criticism of the
EPA's effort.  I am  sure  that  the model  used is  tlie best now
 available.  But I think  that  the model  should be improved upon,  and
periodic adjustments  in  the standards,  and site analysis  should be
undertaken as  those  improvements occur.  An EPA commitment to
                                     98

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                                   25
undertake those improvements and modifications  or  guidelines  would go
a long way to reassuring the populace around Rocky Flats  that the best
possible theories are being used to  ensure  their safety.

     Staff Response - The mass  loading  approach is an averaging over
many *'non equilibrium" conditions which can occur  during  the  course of
a year.  It is recognized also  that  there are  localized disturbances
which would not be reflected in the  general mass loading  level.  The
agency staff has attempted to scope  the impact of  such localized
disturbances (see Annex  II) and concluded that the soil screening
level is sufficiently conservative  in  these situations.
The Guidance is a recommendation on  dose limits for transuranium
elements.  The screening levels for  air and soil are administrative in
nature and are only for  the purpose  of  identifying areas  where
remedial actions may be  necessary.   Site-specific  data should be.
collected and the potential pathways analyzed  in order to determine
whether remedial action  is requiredi     •  ••>                   »     •

     The agency staff concurs that,  if  significant new information
should become available  in the  futurej  changes in  the Guidance would
be appropriate.

52.  Representative Timothy Wirth                                 :

     I think  that  the analysis  of  the  dust  problem could be refined by
further  research.   Is the  distribution of radio-active elements in  the
dust the  same per  unit  weight  as  in the top cm. of soil,  or are there
differences both  in total  dose/gra.  and in the  size distribution of  it,
for  example. •.                                                   , ,
                               •     i   : ••.".     •   .' ,       -
     Staff Response — There  should be  a difference in  the activities
per  gram of  suspended dust verses  the  activity per gram of the total
soil.  The  activity per gram of the airborne dust can  either be
enhanced or  diminished  depending upon  the way  in which the activity is
distributed  in the parent soil.  If the activity  is  primarily
associated with the larger,  less resuspendible soil  particles, the
activity per  gram of the suspended dust would  be  lower;  if the
 activity is  associated with the smaller soil particles,  the
 resuspended  material would have a higher activity per  gram than  the
 parent-soil'., v -  -   •   •     •          ••! • -v -   .     •     ••••-.-  .-••«.    .-i

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 3.3  Annex  III - The Dose  and  Risk to  Health  Due  to  the  Inhalation  and
      Ingestion of Transuranium Elements

 1.   Dr. Edward Martell

      Organ burdens of  fallout  plutonium  in  the general public have
 already reached levels of  (approximately) 0.5 pCi/kg in  lung tissue,
 (approximately) 0.7 pCi/kg in  the  liver, and comparable  levels  in the
 gonads and other organs (Moss  and  Campbell, 1972).  Depending on the
 microdistribution of this alpha activity in the gonads and at tumor
 sites and on the mechanism of  cancer induction, this fallout level of
 alpha activity may be contributing substantially to the rising general
 incidence of cancer and genetic effects in man.  If so, exposure of
 large sectors of the general public to 200 times higher levels would
 have tragic consequences.  Based on present knowledge, the only
 responsible recommendation regarding public exposure to insoluble
 alpha emitting particles would be that such exposures be restricted to
 the practical minimum.   That practical minimum is, unfortunately, the
 level of fallout plutonium in surface soils.

      Staff Response - The data for fallout plutonium in tissue used by
 Dr. Martell are taken from LA-4875, Plutonium in Autopsy Tissue.  It
 was later discovered that a standardization error invalidated most  of
 these measurements.   The 1972-73 data reported by the same group in
 WASH-1359,  Plutonium and Other Transuranium Elements; Sources.
 Environmental Distribution and Biomedical Effects are more reliable
 and report  somewhat  smaller organ burdens.   More  important,  both data
 sets have a high  degree of measurement  errors  and considerable
 variation between different individuals.   As described in Annex 3 of
 the Technical Summary,  they do not provide  a means for estimating
 organ burdens with confidence.

      The  Agency's analyses  show that  the  number of persons likely to
 be  exposed  at the proposed  limit  is small.   Contrary  to Dr. Kartell's
 statement,  it is not anticipated  that "large sections  of  the  general
 public" will  be exposed  to  limiting dose  values.   The  setting of
 Federal guidance at a dose  level  corresponding to  average  background
 radiation levels disregards the uneven  distribution of plutonium in
 the  environment and the costs required  to return nature to a pristine
 state.
2.   Dr. Edward Martell

     In the production of chromosome aberrations the biological
effectiveness of high-LET radiation is independent of dose rate and ig
much greater than that of X-rays and gamma rays (low-LET radiations),
particularly at the low intensities of natural background radiation.
                                ire

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Upton has pointed out "Under conditions of  low-level  irradiation most
pertinent to environmental carcinpgenesis,  therefore,  the  oncogenic
potency of high-LET radiations is generally assumed to be  relatively
high, i.e., 10 to 20 times that of X and gamma  rays"  (Upton,  1967).
There is growing evidence that the RBE for  somatic mutations  induced
by high-LET radiation at the low dose rates applicable to  background
radiation are even larger, with RBE values  ranging from  35 to 100
(Davis and Bateman, 1963; Neary et al., 1963).  This  is  consistent
with the long term repair of mutations induced  by low-LET  radiation
and the resistence to such repair for mutations induced  by high-LET
interactions (Curtis, 1966).

     Staff Response - RBE values were not used  to assess cancer risks
in the proposed guides.  Rather, the hazards  from alpha  radiation were
assessed directly from human effects data.  For genetic  mutations an
RBE of 100 was used.  This is consistent with the upper  range
considered by Dr. Kartell.
3.   Dr. Edward Kartell

     Insoluble alpha emitting warm particles (i.e., colloidal  thorium
oxide and, uranium metal dust) have been demonstrated  to be highly
effective in lung cancer induction in mammals and man  (Suckow  ejt aJL^,
1961; Heuper et al., 1952).  By contrast, inhalation exposure  to high
levels of radon and its short-lived daughters was singularly
ineffective in promoting lung tumors in mammals but gave  raise to  life
shortening and other effects (Morken and Scott s 1966).  Such
apparently disparate effects for inhaled alpha emitters are readily
reconciled on the basis of the "warm particle" hypothesis (see below)
which implies a high cancer risk only for insoluble alpha emitting
particles which persist in small volumes of tissue and give rise to
alpha interactions with cell at frequencies which optimize the
multiple mutation process.  The results of Morken and  Scott suggest
that, at highly elevated levels of natural alpha activity (which is
soluble in body fluids), the critical somatic  cells which determine
life span usually receive excessive radiation  damage  before the
saulti-stage process of lung cancer induction is completed.

     Staff Response - The Morken and Scott article referenced  by Dr.
Kartell is outdated.  Chameaud , et al-. , (J. Chameaud,  et  al. ,
pp. 411-421 in Experimental Lung Cancer . Springer-Verlag ,  1974) showed
that, for rats, at least, nearly pure "2Rn an<|
                                                 222
                                                    Rn
 daughters produced adenomas and carcinomas equally well with and
 without uranium ore dust while the uranium ore dust alone was
 unsuccessful in inducing either adenomas or carcinomas.  The "warm
 particles or clusters of particles" of uranium ore dust seesn
 singularly unsuccessful in inducing tumors in this test system.

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 4.   Dr. Edward Kartell

      The foregoing considerations indicate that, of the various
 sources of ionizing radiation to which man is exposed, internal alpha
 eaitters merit special attention with regard to their possible role in
 the^etiology of human cancer.  The fact that participate alpha
 activity in the lung gives rise to cancer, whereas, uniformly
 distributed alpha activity associated with elevated levels of radon
 results in life shortening with no cancers clearly indicates that the
 practice of averaging the organ burden and the radiation dose for
 internal alpha emitters is unjustified.  It is obvious from these
 considerations alone that the incidence of alpha radiation induced
 cancer must be highly dependent on its distribution.  It also follows
 from these considerations that the linear hypothesis of carcinogenic
 response to radiation is not applicable to the assessment of cancer
 risks from alpha radiation.  The mounting evidence which indicates
 that insoluble alpha emitting particles which persist in tissue may be
 implicated in the etiology of bronchial cancer in cigarette smokers is
 briefly reviewed below.

      The possibility that the alpha emitting radioisotope polonium-210
 aay be involved in the etiology of bronchial cancer in cigarette
 smokers was first proposed by Radford and Hunt (1964) and relatively
 high concentrations of polonium-210 were found in the bronchial
 epithelium of low lobe bifurcations in cigarette  smokers  (Little et
 «!•» 1965).  More recently it was  found that  radioactive  lead-210~the
 22year halflife grandparent  of polonium-210,  is  highly enriched on
 tobacco trichoraes and  in the  unsoluble smoke  particle formed by the
 combustion  of trichomes in burning cigarettes  (Kartell,  1974).   The
 presence of elevated levels of lead-210 as well as  polonium-210 at the
 bronchial tumor sites  of cigarette smokers has been confirmed  (Radford
 and Martell,  1977).  It has been pointed out  that  the  insoluble
 radioactive smoke particles which  persist  in  tissue would be very
 effective agents  of  cancer if the  mechanism of alpha radiation  induced
 cancer  proceeds via  a multiple mutation  process (Kartell,  1975).   A
 multi-step  process of alpha radiation induced  cancer,  referred  to  as
 the  "warm particle" hypothesis,  is described briefly below and  in
 attachment  #1  (Martell,  1977).

     The hypothesis of  alpha  radiation  induced lung cancer,  briefly
 described in attachment #1, provides  a preliminary  consideration of
 the  sequence of events which  may be involved in the  induction of
 bronchial carcinoma in cigarette smokers.  It involves a  four stage,
multiple mutation process,  as  follows:

     Stage  1;   The slow accumulation  of  insoluble alpha emitting
particles in damaged bronchial tissue.  This process is markedly
 influenced by physical and  chemical cofactors which damage the
bronchial epithelium and thereby enhance the uptake of particles.

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     Stage 2:  The production of premaligttant cells' by alpha radiation.
induced mutations.  Most of the mutations induced by alpha
interactions are either lethal or-have adverse mitotic effect.  The
latter are eliminated by selection over successive cell generations.
The premalignant cell is conceived to be a transformed cell with .any
of a variety of and/or combination of structural changes which give i£
a proliferative advantage over normal cells.  It is proposed that
premalignant cells have normal mitotic controls and normal mitotic
rates but suryive longer to divide a greater number of times than
normal cells.                              ,             -
                                                   ;         "•'-.-••
     Stage 3;  The selective proliferation of premalignant cells -in.
limited clones.  This .process proceeds at a stimulated.nitotic rate9
driven by the relatively high rates of lethal alpha interactions in
the environs of warm alpha emitting particles.  This process can be
stimulated by other agents which kill cells and thereby enhance
mitptic activity.

     Stage 4;  Malignant cell formation by an alpha radiation induced
change in any one of the premalignant cell which results in  its loss
of normal mi totic controls.  This is the fully malignant stem cell
which undergoes, rapid, uncontrolled proliferation to form a  tumor.

     The first three stages of the, proposed sequence of events proceed
concurrently.  The induction of additional structural changes in   .
premalignant cells and in the outgrowth stem cells also is a
continuous process which can explain the wide variety of kayotypes.in
lung tumors, the occurrence of multiple stem cells in some .tumors,
etc.  Thus, insoluble alpha emitting warm particles which can
accumulate and persist in damaged bronchial tissue, and perhaps at
other tumor sites as well, provides.a carcinogenic agent capable of •
inducing the cytogenetic changes observed in bronchial carcinomas  and
most other malignant human tumors (see Atkins in German-,. 1974).

     The warm particle hypothesis indicates a lung tumor incidence
proportional to the duration of smoking in years to the  fifth power,
consistent with the best epidemiological evidence (Doll, 1971).  The
proposed mechanism als'o involves a mitotic activity dependence  term
and thus provides a basis for explaining the surprisingly similar
incidence of common tumors in mice and men (Brues, 1959).

     A key point  in the warm particle hypothesis, and one apparently
not considered heretofore by radiobiologists, is the critical point of
transition between "warm" and "hot" alpha emitting particles which
depends on the frequency of alpha interactions with cells and the
cellular response.  To optimise the multiple mutation process in  small
cell populations, the frequency of alpha interactions should not
exceed about"one  critical hit per cell per day,  the approximate  time  ;

-------
required for a mitotically  stimulated  cell  to proceed  through  the
complete mitotic cycle and  divide.  This  transition  point  is
approximately 0.01 picocuries of alpha activity per  particle,  the
upper limit for warm particles.

     Perhaps the most important implications of the  warm particle
hypothesis are that natural alpha activity  in its natural  form has
negligible carcinogenic risk and that  the carcinogenic risk from
insoluble alpha emitting particles that persist in tissue  is highly
dependent on the alpha activity per particle, on the microdistribution
of such particles, and on the properties  of the target cells.

     Staff Response - As noted in the  response to the  previous
comment, recent experimental tests have failed to show a high
carcinogenic response to warm particles.  In the absence of bioeffects
data to support the "warm particle" model,  it must be  considered
spectulative.  Moreover, many aspects  of  Dr. Kartell's model for lung
cancer induction are based  on dated references with  little
consideration given to current models  of  carcinogenesis.   In
particular, Knudson (A. G. Knudson, Jr.,  pp. 45-52 in  Origins  of Human
Cancer, Cold Spring Harbor Laboratory, 1977), Anderson (D. E.
Anderson, pp. 39-54 in Persons at High Risk of Cancer Academic Press,
1975) and Kersey and Spector (J. H. Kersey  and B. D. Spector,  pp.
55-67, Ibid) have considered mutational models in the  light of genetic
predisposing conditions.  Knudson, in  particular, concluded that
either 2 or 3 events are necessary to  produce a cancer, with 3 event
cancers usually being karyotypically abnormal.  Recent reports
indicate that the oat cell  carcinoma of the lung, the  carcinoma
usually associated with lung irradiation, is karyotypically abnormal,
with marker chromosomes (E. R. Fisher, e_t al., Am. J.  Clin. Path. 69:
165-172 (1978).

     Moreover, additional work is needed  to confirm  obervations and
identify sources of 2^Po and 2-*-^Pb before  the assumptions of
Martell may advance to the hypothesis  stage.  Although assumptions
made by Dr. Martell concerning the distribution of Pb^lO and Po2l"
in smoke and smokers may be consistent with the work of Radford and
Martell (1977), they remain only assumptions, and extensive work would
be necessary to prove and expand the preliminary findings.  Other
sources of Pb2^ and Po2^ must be investigated in addition to
smoking.  Many of the sources that may contribute have already been
identified by Moore, Martell, and Poet (1976).  For  example, short
term inhalation of dust while raking and bagging leaves might  lead to
deposition of particles with Po210/Pb210  ratios of O.4.,
equivalent to ratios seen in "smokers".

     While Dr. Martell's model is interesting and bears watching, it
is not quantitative and is  likely to undergo extensive modification as
it evolves into a less speculative model  of cancer risk.   It
definitely cannot be used in standard  setting in its present form.

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5-   Prv Edward Martell

     The proposed EPA guidance  is based  on  the  assumption  "that  the
risk at any given low dose  level  is directly  proportional  to  the
damage actually observed at much higher  dose  levels."   Such an
assumption is particularly  inapplicable  to  internal  alpha  emitters and
can lead to an underestimation  of the  cancer  risks  for  insoluble alpha
emitters by factors of hundreds to thousands  or more, for  reasons
briefly considered here.

     Many of the important  limitations of the linear hypothesis  were
reviewed by Brues (1958, 1959).  With  reference to multiple mutation
mechanisms like that proposed by Armitage and Doll  (1957)  which  is
reconciled with the age-incidence of cancer in  man,  Brues  (1958)
comments, "This, if applied to  radiation, would imply an exceptional
effectiveness of widely spaced  dosages,  which does not  appear to have
been observed."  I must comment that one cannot observe what  one does
not look for.  -It is^proposed that insoluble  "warm"  alpha  emitting
particles which persist at  tumor sites,  give  rise to malignancy  via a
multiple mutation process (attachment  #1).  Insoluble warm particles
which accumulate and persist at human  tumor sites appear to me to be,
the exceptionally effective radioactive  carcinogens  that Brues and
others have overlooked.  As noted above, warm particles may be
expected to give rise to cancer risks  several orders of magnitude
higher than that for the same alpha dose from hot particles,  and the
risks attributable to natural alpha emitters  which are  soluble in
tissue are neligible.  Thus, the warm  particle  hypothesis  is
completely at odds with the linear hypothesis and indicates that the
carcinogenic response is highly dependent on  the spatial distribution
of the alpha activity and the alpha activity  per particle  (or,
alternatively, on the frequency of alpha interactions with the target
cells).  The warm particle hypothesis  and other possible multiple
mutation models can be tested experimentally.   It is very  important
that we,do so.

     The results of Morken and Scott (1966) discussed above (comment
3) also are at odds with the linear hypothesis  but are  readily
reconciled with the warm particle hypothesis.   These results  imply
that, to be most effective for tumor induction  rather than
life-shortening, elevated levels of alpha radiation  should be
restricted to a small tissue volume in the  organs at risk.  On this
basis, small populations of insoluble  alpha emitting particles which
persist in small volumes of tissue sites would  appear to have
exceptional carcinogenic potential.

     The practice of averaging alpha activity burdens and  doses  for
each organ, usually necessitated by lack of adequate information on
the microdistribution, has futher compounded  the confusion with  regard
to the biological end effects.  The average alpha radiation dose for

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an organ or tissue volume, in which many of the cells are not
irradiated at all and others are killed by an excessive number of
alpha interactions, is a completely unreliable index of effects.  Even
when the high-LET irradiation pattern is known, the biological effects
are still not a simple function of dose adjusted by an arbitrary
quality factor, as Katz and Sharma (1974), Brustad (1961) and others
have pointed out.

     On the basis of the foregoing considerations, the basis of risk
estimates for the proposed guidance is hopelessly inadequate and, for
a multiple mutation process of cancer induction, grossly
underestimates the risks for alpha emitting warm particles.

     Staff Response - Dr. Kartell's contention that the linear
hypothesis underestimates risk by orders of magnitude is not supported
in this argument nor by animal data.  Experiments by Chameaud e_t al^,
(j. Chameaud, e£ al., pp. 411-421 in Experimental Lung Cancer,
Springer-Verlag, 1974) show that, in rats, even filtered radon-222  (an
almost pure diffuse alpha dose) can cause  lung cancer and the more
homogeneous the dose the greater the risk  (j. Lafuma, et al., pp.
43-53 in Radiation Protection in Mining and Milling of Uranium and
Thorium, ILO Geneva, 1976).Similar results have been obtained in
Syrian Hamsters by Anderson, e_t al.  They  found localized irradiation
both alpha and beta, is less tumorogenic than diffuse exposure (E.  C.
Anderson, et al., pp. 10-14 in LA-6898-PR, 1977).  These animal data
are contradictory to Dr. Kartell's suggestion that the risk is
underestimated because of special spatial  dose considerations for
"warm particles.":

     The argument that the use of the 1972 BEIR report risk estimates
is an underestimate of the risk by orders  magnitude  is not  supported.
 6.   Dr. Edward Kartell

     Reports  of the  Advisory Committee  on the Biological Effects  of
 Ionizing Radiation (National Academy of Sciences,  1972 and 1976)  have
 a number of serious  shortcomings with respect to the assessment of the
 distribution  of internal alpha emitters and their  genetic and somatic
 health  effects  as  follows:

     a. Internal  dose:   The contribution of inhaled and ingested
 alpha emitters  from natural and pollutant sources  to the internal
 radiation  dose  at  most critical soft tissue sites  in mammals,
 including  man,  have  not  been determined.  The limited published data
 on  the  distrubution of polonium-210 and radium-226 indicate wide
 variations in their concentrations from organ to organ and within each
 organ.  What  is the  dose contribution at various soft tissue sites for
                                  ire

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                                     8        •  ••       .          '

  the  11 natural alpha emitters:   thorium-228,  radium-224,  radon-220,
  polonium-216, bismuth 212, polonium-212,  radium-226,  radon-222,
  polonium-218, polonium-214, polonium-210?  These  radioisotopes are
  present in some industrial plumes  (Poet and Kartell,  1977)  and inside
  buildings, depending on construction materials  and  other  factors.  The
  added contributions of particulate  alpha  emitters from industrial and
  fallout sources (polonium-210, uranium and thorium  compounds,
  plutonium-239 and americium-241) and their microdistribution  ii
  organs merit particular attention.
microdistribution in mammal
      b.  Genetic effects:  Contributions of  internal alpha emitters  to
 the spontaneous mutations rate and to the genetically significant
 radiation dose have not been determined.  Because of the exceptional
 effectiveness of alpha emitters in the production of chromosome
 aberrations, it is essential to assess their concentrations at the
 germ cell sites.  Relatively high concentrations of polonium-210 have
 been found in the sperm of cigarette smokers (Hunt, 1973) and Green
 et al., (1975) reported higher concentrations of plutonium near the
 sperm sites than elsewhere in the tests.  The presence of insoluble
 alpha emitting particles at the germ cell sites is a disturbing
 possibility that must be investigated experimentally.

      c.  Cancer risks:  The microdistribution and micro-dose
 distribution for insoluble alpha emitting particles at human tumor
 sites, and the cancer risks attributable to such particles on the
 basis of multiple mutation processes, have not been assessed by the
 BEIR Committee.  The possible role of alpha emitting "warm particles"
 in the etiology of bronchial cancer in smokers is discussed briefly in
 attachment #1 (Martell,  1977).   Because alpha emitters are
 exceptionally effective  agents  for the production of the gross
 chromosome aberrations that are present in most human tumors (German,
 1974),  the possible presence of warm particles at other common tumor
xsites also should be investigated.

      d.   Atherosclerosis:   Insoluble alpha emitting particles may be
 implicated in atherogenesis (Elkeles, 1977;  Martell,  1975).   This
 important possibility merits serious attention by the  BEIR Committee
 and the  National  Institutes of  Health.

      Staff Response - The  extent  to which the NAS-BEIR Committee  may
 incorporate Dr. Kartell's  suggestions into their current updating of
 their 1972 Report  is  unknown.   His views were presented  to the
 Committee at  his  request  in July  1976.   In the  past  the  Committee has
 based its  risk estimates  on observed  effects  occurring to persons in
 irradiated groups.  The Agency  agrees that  the  role of  alpha-emitting
 particulates  is an  important  public health question and  that  the
 microdosimetry of these materials  is  essential  to an understanding of

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their potential impact.  Where data is available on this point, it was
incorporated into the Agency's estimates of the risk from transuranium
radionuclides.

     The question of the contribution of "warm particles" to hazards
in solid organs must be deferred until such particles have been
indentified in organs and in areas of interest.

     The relationship of atherosclerosis and "warm particles" is at
best very tenuous.  The co-deposition of calcium and alkaline earth
elements is well documented.  Calcification in fat and calcification
in necrotic and injured cells in the body is also well documented.
The finding of deposited alpha emitters in atherosclerotic lesions may
not be significant.  The "warm particles" certainly do not fit easily
into the picture of atherosclerosis pathology developed by French
(J. E. French, Intern. Rev. Exper. Pathol. 5^253-353 (1969).
7.   Dr. Edward Kartell

     The foregoing discussion indicates that the proposed guidance is
based on hopelessly inadequate information on the internal
distribution of alpha emitters and their genetic and somatic effects.
Additionally, the assumptions and models used as the basis of risk
assessment are highly questionable and may lead to very substantial
underestimation of cancer risks and genetic effects.

     Consequences of public exposure  to transuranium elements in  the
environment are extremely serious questions which should be addressed
by the most knowledgeable and objective scientists in  the field of
radiation health effects.  It is far  from clear that the unidentified
scientists who generated the proposed guidance have such credentials.
The quality and content of the guidance report suggest otherwise.

     Based on present state of knowledge of the genetic and somatic
health effects of insoluble alpha emitting particles,  public exposure
to such particles must be restricted  to the practical minimum—several
times fallout or less."

     Staff Response - Dr. Kartell's conclusion that the proposed
guidance is based on "hopelessly inadequate information" is somewhat
overstated.  The Agency uses dose models developed by  an international
commission of radiation protection experts.  Similarly, analyses  of
radiogenic lung cancer developed by the National Academy of Sciences
and derived from exposure of humans to radiation are used to estimate
risk.  The question is not whether the Agency's scientists are
knowledgeable or objective, but whether they could responsibly
disregard this information, developed by a large group of scientists,
on the basis of the untested model of carcinogenesis proposed by  the
commentor.
                                ire

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                                    10

     Where possible, the guidance  is based  on  epidemiological
information on  the hazard  from  alpha emitting  radioelements.   The  risk
estimates used  are tempered with information from  animal  studies and
from other human exposures.  While there  is uncertainty in the risk
estimates, it is not orders of magnitude  and probably  is  less  than a
factor of 5.
8.   National Council on Radiation Protection
     The factors for the uptake from the GI  tract  in Annex  III  are  of
considerable importance because they are orders of magnitude  higher
than have been used.  However, there is practically no  justification  .
for them nor is the estimated degree of conservatism indicated.

     Staff Response - The basis for the selection  of these  factors  is
given in Section 6 and in Technical Note CSD-78-1  (selected topics:
Transuranium Elements in the General Environment,  Office of Radiation
Programs, EPA, 1978).
9.   Colorado Environmental Health Association

     As for the guidance itself, Johnson  (1977) in a paper presented
to the Annual American Public Health Association has reported
increased leukemia death rates in the eight census tracts nearest -
Rocky Flats as compared to nineteen census tracts located in southern
Jefferson County.  These death rates range>from 2 to 3 times the rates
from southern Jefferson County.  The census tracts nearest Rocky Flats
range from 3 to 33 mCi/km2 .or 0.003 to 0.033 uCi/m2 in plutonium
contamination of the soil.  The. proposed  guideline of 0.2 uCi/m2 is
from. 6 to 66 times the level associated with increased leukemia rates
according to the study.

     Staff Response - Dr. Johnson's 1977  report on a possible
association between plutonium contamination and the annual rate of 4
leukemia deaths around Rocky Flats and 1  leukemia death in Golden
County (as compared to 2 leukemia deaths  in southern Jefferson County)
is premature.  As Dr. Johnson points out, local (cancer mortality)
rates vary widely.

     J. Sutherland (Director of the Cancer Patient Data System,
Regional Cancer Center, Denver) pointed out in his June2, 1978, memo
to the Rocky Flats Monitoring Committee:  "Because of the small numbers
of cases involved, it is important that another control area be
identified to compare to the Rocky Flats  area.  It would not be
surprising to find a random fluctuation of 2 cases of leukemia in
various areas of Colorado.  For example,  the number of thyroid cancer

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                                   11

deaths in Colorado fluctuates from one to eight cases per year during
the period 1960-1976 with no discernible trend.  The eight cases in
1968 are much different than the two cases in 1969, but this
difference is meaningless."

     Sutherland also pointed out possible problems in accuracy of
diagnosis available from death certificates, mobility of the
population and the need for examining the incidence pattern over an
extended time period.  He concluded: "The results reported by Dr.
Johnson are preliminary and of a suggestive nature only, and provide
no conclusive evidence of anything due to small numbers  of observed
cases  over a single year using death certificates.  I feel that Dr.
Johnson has stated this in his presentations, but perhaps not
forcefully enough."

     Indeed, Dr. S. W. Ferguson (Chief, Chronic Disease, Colorado
Department of Health, Denver) pointed out in his February 23, 1978,
letter to Dr. Carl Johnson (Director of the Jefferson County Health
Department) that the Rocky Flats and control areas examined by Dr.
Johnson each have a lower combined lung and leukemia incidence rate
than was observed in two other control areas, one in Jefferson County
and one in Arapahoe County.  Dr. Ferguson also pointed out that
population growth rates in the census tracts examined may play an
important part in interpretation of the cancer rates.

     Before an association of plutonium contamination and leukemia can
be inferred, data must be available for a number of years to average
out the normal large fluctuations in annual death rate seen in small
populations.  Duration and comparability of residence times in the
area must be established, comparability of populations for
occupational and environmental exposure to known carcinogens, current
and prior exposure, age, and sex distribution, etc.,  must also be
estimated.  Dr. Johnson has yet to adjust for these variables.
10.  Department of Defense

     Basic Guidance:  The proposed guidance of 1 mrad per year to the
lung and 3 mrad per year to the bone are considered to be overly
restrictive, possibly by a factor of 100.  If this is true, screening
levels and permissible annual dose rates should be increased
accordingly.  Explanations follow:

     The Summary Report gives risk estimates derived from an EPA Life
Table Methodology.  An illustration of results using the EPA
Methodology and NAS-BEIR data is given in Annex 4, pg. 9 of the
Summary Report.  Background radiation (100 mrem per yr) is indicated
to cause 144 premature deaths per cohort-lifetime.  (The single value
is determined as an arithmetic mean of geometic mean relative risk and
                                  110

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                               --». 12

geometric mean absolute risk, where the geometric means, are of  two
"plateau" values.  This averaging method is presumably  the one
followed by EPA elsewhere in the Summary.Report).  Since  lifetime is
71 years the EPA Methodology yields 2 deaths per cohort-year due to .
background radiation.  The NAS-BEIR Report (pg.  169) yields 3614
"excess deaths" per US-Population-Year due to background  radiation.
(This value is determined also as the arithmetic mean of  geometric
means of data given at pg. 169),  This value can be expressed in
similar units to those used by EPA—assuming 200 million  persons as,US
Population, and 100 thousand persons in a cohort, the NAS-BEIR risk
methodology gives 1.8 extra, premature deaths per cohort-year.  Thus,
the two risk methodologies yield equivalent results when  evaluating
background-radiation impact.

     The NAS-BEIR Report shows (pg. 171) absolute risk  of lung  cancer
as 1.3 per million-person-year-rem.  (Similar values are  given
elsewhere in the Report; e.g., "beat" risk estimates range from 0.07
to 1.6 on pg. 151, and the average for adults only is given as  1.0 on
pg. 150.  These estimates are primarily on case  studies of persons
chronically exposed to radiation).  The NAS-BEIR input  data is  given  ,
in rad units, and conversion to rems is made in  the Report by using an
RBE of 10.  Absolute risk of lung cancer according to NAS-BEIR  then,is
13 deaths per million-person-year-irad, or 0,013  per million-person-
year-mrad.                                                   -,.,     .

     The EPA Rationale for Guidance states "The  risk at the proposed
guidance level is estimated  to less than one chance in  a  million.per
year...". , As used in this instance, "less than  one" means "in  the
order of one" since the value  is obtained by dividing the risk  per
cohort-lifetime  (10 deaths)  by 71 years.  Since  the proposed  lung
guidance.level is 1 mrad per year, the EPA Methodology  gives  a  risk of
1.4 deaths per million-person-year-mrad, in contrast to 0>013 deaths
per million-person-year-mrad estimates by NAS-BEIR Methodology.

     Since the EPA and NAS-BEIR methodologies  give equivalent results
for estimates of background  radiation effects, one would  not  expect
estimates to differ by a  factor of 100 for the case of  lung  radiation
effects.  The,reason for  this  discrepancy is not apparent in  the
background material provided.  Perhaps the real  answer  will  be
apparent when EPA "in-preparation publications"  (References  1,  6  and
9, Annex III and 5, IV) are  made  available for review.  If not, then  .
EPA should provide an explanation for the apparent difference.

     The Summary Report makes  the case that a  risk of  "one in a
million"  is  suitable for  transuranics in the environment  because  it  is,
comparable to risks used  for other carcinogens.  If  the NAS-BEIR  risk
estimates are correct, the EPA estimates are in  error  and the risk  of ,
one-in-a-million is.to be maintained, then  the proposed guidance  must
be  stated as  100 mrad per year to the pulmonary  lung,  not 1 mrad  per
year.  Bone  dose and screening levels also must  be  increased.

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                                    13

     Staff Response - This  comment  is based  on  an  erroneous
interpretation of  the information on absolute risk given on  page 171
of the 1972 NAS-BEIR Report.  The absolute risk for lung cancer  is
listed as "1.3/106/year/rem."   This risk  coefficient in the  1972
BEIR Report means  that the  probability  that  an  individual will die  of
excess lung cancer following a  one  rem  dose  is  1.3 x 10~6 for each
person year at risk.  It  is not the risk  for a  given dose rate (rem
per year).  This interpretation can be  verified by calculating the
absolute risks tabulated  for total  cancers on page 173.

     Because an individual  averages about 35 person years of risk for
each annual dose increment  received over  a lifetime (lifetime
plateau), the lifetime risk is  about 35 times larger than assumed by
the commentor.  Moreover, averaging relative and absolute risks  and
considering the increased effect of childhood exposure  increases the
risk estimates by  an additional factor  of about 3.   The  neglect  of
these factors by Department of  Defense  has the  overall  effect of their
underestimating the risk  by a factor of more than  one hundred.
11.  Colorado Department of Health

     The Department has been allowed  to review  and  comment  on  several
of the earlier drafts.  Each time we  have requested simplified
equations to inform the reader as to  the relationships between the
risk, the biological risk estimator,  the dose or  dose rate  commitment,
the air concentration and the soil concentration.   While  the entire
document does address these matters,  nowhere is the relationhip
summarized to place the entire process in prospective.  Additionally,
we have also commented that all of the equations  be provided in
detail.  The "Plutonium Air Inhalation Dose (PAID)", Technical Note
ORP/CSD-77-4, document was an attempt to provide  the dose calculation
procedures used by EPA in the development of the  guidance.  While our
review of this publication is currently incomplete,  there are  some
rather important defects involved.  Figure 1, page  5, has improperly
depicted pathways (d) and (g).  Appendix I does not identify the terms
used in the derived equations to allow another  agency to  use it with
relative ease.  The equations as provided are incomplete, as there are
summations that must be done for each equation.   Appropriate notation
is necessary if the equations are to be correct.  Appendix  II  does
provide an example; however, the values used are  not easily
discernible.  With the provision of the term identification in
Appendix I and the values in Appendix II, calculation to  confirm the
EPA process would be properly provided for.  It must be pointed out
that the EPA and this Department's chronic exposure dose  rate
calculation procedures produce results not significantly  different for
the same parameters.

     Staff Response - The misprint in Figure 1 of the PAID  document
was inserted when this figure was drawn.  The equations and computer
•                                    •? O
                                    & c-

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                                   14

code are not affected by this error.  The;equations in the PAID
Appendix I are complete in that they are valid for any organ or  lung
compartment in a chain.  While they must be summed to obtain total
dose/dose rate, the summation process is described in the main text*
While the request for a simplified set of equations is understandable,
it is not likely that any such set would cover the range of cases
considered in the guidance document.  The computer code is available
on request from EPA.                                 ,
12.  Colorado Department of Health

     Annex III of the guidance document provides  data  on various
aerosol particle size distributions  and resultant doses, etc.   The
ICRP in adopting the TGLM Clearance  Model used  only  a  1 urn AMAD
aerosol particle size distribution.  The pathway  parameters
recommended by the ICRP are based on that particle size for  deposition
in the various compartments of the respiratory  tract and translocation
to the blood and gastro-intestinal tract.  The  use of  particle sizes
considerably smaller than 1 urn AMAD  for Class Y compounds  will result
in an underestimate of the health risk due to the greater  effective
solubility of the smaller particles.  The document references  particle
size distributions down to 0.01 urn AMAD; however, the  tables in Annex
III do not include that particle size.        .

     Staff Response - The question in not clear.   While,the  ICRP
recommended that, for unknown aerosol size distributions,  a  1  urn  AMAD
be used in the ICRP model-, the ICRP  Task Group  Model is applicable  to:,
a wide range of particle size distributions  (Figures 13 and  14 of Ref.
5).  One  limitation of the model is  that solubility  is a function of,
the compound class and is not related to particle size.  The guidance
document  was based on particle sizes from 0.05  urn to 5.0 urn.  Typical
results for this range of sizes are  given in Annex III.  This  size
range encompasses most aerosol distributions (Ref. 5,  p. 183).
Aerosols  consisting of smaller particles are.outside the range of
validity  of the ICRP model (Ref. 5,  p.  185)  and,  in  any event,, are
expected  to result in decreased, not increased, pulmonary  deposition •
(Ref. 5,  p. 185).

     The  question of  increased solubility has been considered by  EPA.
Some typical results  for Class W compounds.are  given in Section 6.


13.  Conference of Radiation Control Program Directors

     The  method of calculating, dose  must be  more  explicit  so that the
entire procedure can  be duplicated by  those  interested. -,. It  should
also be pointed out in the document  that fresh  soil  contamination may
be a Class W compound which would provide  a  greater  hazard to the
                                   113

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                                    15

bone.   The basic  guidance should be the primary controlling factor.
In  some circumstances  reliance  on the  Class  Y data and the associated
soil screening  value will not provide  adequate protection.

     Staff Response -  The method used  in calculating doses is
relatively standard in that  it  follows the ICRP TGLD-lung model  and,
for the most  part,  uses ICRP metabolic parameters  for the reference
organs.  Estimates  of  the hazard of Class W  compounds can be found in
Section 6.                                      ,,     .

     The "soil  screening" level is  specifically designed  to address
only those cases  where inhalation is the primary pathway  to man.   In
most cases of environmental  contamination, the suggested  screening
level of 0.2  uCi/rsr- leads to pulmonary lung  and/or bone dose rates
well below the  Guidance recommendations.   The lung dose rate is
generally governing because  newly deposited  transuranium  element
contamination,  which may consist of very fine particles,  is relatively
insoluble.  The more weathered  and  soluble particles are  expected  to
have a  larger activity median aerodynamic diameter (AMAD).
Section 6.3.2 in  this  volume describes the application of the  proposed
guidance to Class W transuranium compounds.   In a  few cases where
alternative pathways,  such as ingestion,  comprise  a significant part
of the  total  exposure,  these must be considered on a site-specific
basis.
14.  National Resource Defense Council

     EPA underestimated the somatic and genetic effects of  low
dose/low dose rate irradiation.

     Staff Response - Somatic Effects - The Agency notes  that risk  to
health due to transuranium elements in the environment is almost
entirely due to high LET (alpha particle) irradiation and that  the
Agency's risk estimates are based only on the potential effects of
alpha irradiation.  With the exception of Dr. K. Z. Morgan's paper,
the references on somatic risk cited by the NRDC discuss  the effects
of low LET radiations.  While the Agency agrees there is  considerable
controversy concerning the effects of low LET radiations, none  of the
new studies cited by the NRDC provide information on the  risks  due  to
chronic exposure from internally deposited alpha particle emitters.
Dr. Morgan's discussion of the inhalation hazard due to plutonium is
based on acute effects from massive doses, (kilorem) not  cancer risk.
The baboon studies he cited are not relevant at the low doses where
delayed cancer, not acute health effects, are the potential public
health problem.

     The Agency agrees with the 1972 NAS-BEIR Committee that the
linear hypothesis may either overestimate or underestimate the risks
                             114

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                                   16

due to-low'levels of ionizing radiation (EPA-520/9-73-003-D);        "
However, as stated in Annex III, the Agency believes appreciable
departures from a linear response are less likely for high LET  than
low LET radiations.  Nevertheless, the Agency recognizes  that all
current risk estimates are of necessity based on incomplete  data.  '.
Because of the uncertainty in radiation risk estimates, the  Agency
contracted with the National Academy of Sciences in 1976  to  constitute
a new BEIR Committee to reevaluate the potential health risk due  to
both high LET and low LET radiations.  This Committee is  reviewing the
most recent radiation health effects information, including  that  on
alpha particles, in order to determine to what  extent the 1972
NAS-BEIR Committee risk estimates used in the preparation of these
Guides may be changed.  The Agency will consider the need for
modification of its risk assessment upon completion of the NAS  study
in 1978.

     Staff Response continued - Genetic effects - The >NRDC cites  two
studies to support its view that the estimate of genetic-  risk is  too
low.  The first by Dr. M. F. Lyon calls attention to a possible
increase in genetic risk at very 'low-dose -rates over that calculated
by the BEIR Committee in 1972.  The EPA risk estimates are for  alpha
particle emitters.-and therefore do not assume fewer effects  at
low-dose rates.  As explained in Annex III, the Agency's  estimates of
the genetic risk is five times greater than that of the 1972 BEIR
Committee.  The other study cited by the NRDC is the report  by  B. K.
Trimble and J. H. Doughty on the frequency of genetic disorders found
in British Columbia.  The reported frequency in British Columbia, of
disorders having a complex etiology, which includes a genetic
component, is a factor of two greater than that li'stefd in the 1972
NAS-BEIR report; 90 per 1000 live births as compared to 45 per  1000.
The important question however is the degree to which these  diseases
have a mutational component,' i. e., are transmitted  to future
generations.  The 1972 NAS-BEIR Committee estimates their mutational
component as between 5 and 50 percent and the Agency's genetic  risk
estimates in Annex III are based on this range  of possible values.
Recently," (1977) UNSCEAR has estimated ten percent  as an  upper  limit
for this mutational component.  Therefore, the  Agency believes  its
estimate of genetic risks is conservative and that  the range of
genetic risks presented in Annex III encompasses the factor  of  two
reported in British Columbia study.  The Agency notes1 that until  his '
recent death,-Dr. Trimble was a member of the NAS-BEIR Committee
reevaluating their 1972 report and that his studies will  be  considered
in preparing the Academy's new estimates of genetic risk  to  be
published this year.
 15.  Natural Resources Defense  Council

     By using  an  incorrect  relative  damage factor for bone,  EPA
 underestimated the  radiotoxicity of  plutonium in bone.
                                    5

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                                    17

      Staff Response - The relative damage factor "n" had been used by
 ICRP Committee 2 to relate the risk of bone cancer due from radium-226
 uniformly deposited in bone to the dose and risk from plutonium and
 other radionuclides which deposite on bone surface and thereby
 irradiated a larger proportion of cells at risk for cancer induction.
 Since in both cases the dose was calculated by averaging the emitted
 energy throughout the skeletal mass, the n factor corrected for the
 uneven deposition of energy by bone surface seekers.  It should be
 noted that the ICRP has recently (1977) defined dose-to-bone in terms
 of the dose-to-bone surfaces and defined a quantity N "the product of
 all other modifying factors",  (except the quality factor, Q) as
 unity.  In view of the context of the NRDC comment, it is assumed here
 that the NRDC comments refer to n, "the relative damage factor for
 bone", and not the quantity N.

      In its review of the data of radiogenesis of bone cancer, the
 Agency carefully considered the precedents established by the ICRP,
 K.  Z.  Morgan,  and others in relating estimates of risk due to
 radium-226 to  other alpha emitters.   However,  the Agency staff
 concluded that such an approach was  too indirect because of the
 dosimetric difference between  the results of  radium-226 and plutonium
 deposition and,  instead, used  a more direct approach based on
 epidemiological  studies of persons chronically irradiated with
 radium-224 which,  as explained in Annex III,  irradiates only bone
 surfaces.   These data were not available when  the n factor concept was
 developed by  the ICRP.   Contrary to  the NRDC  comment,  no  N or n factor
 has-been implied by the Agency in its  evaluation of the risk of
 radiogenic bone  cancer.   Rather,  the risk estimate is  the result of a
 straightforward  application of the most relevant biological data on
 the results of human exposures.
16.  Natural Resources Defense  Council

     EPA did not  consider  the harzard of hot  particles  in the
induction of lung cancer.

     Staff Response- The Agency agrees  with the National  Academy  of
Sciences' study that concluded  that, if there is  a hot  particle risk,
it is small by comparison  with  lung cancer  risk attributable to the
generalized alpha radiation  (NAS-76).   As pointed out in  Annex III,
the Agency's estimates of  the risk of lung  cancer are conservative in
that it is based  on the dose to that portion  of the Agency  receiving
the highest average dose,  the pulmonary region, notwithstanding the
fact that most radiogenic  lung  cancers  in humans  are found  in the
bronchial region  where the dose at the  proposed limits  is a factor of
more than ten smaller, Table 3-2, Annex III.   The Agency's  position on
the hot particle  hypothesis and the NRDC petition to use  this
hypothesis as the basis for Agency estimate of risk due to  the

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                                   18

inhalation of plutonium was published in 1977, 42 FR  1288.  While  the
Agency has ,been aware of the NRDC's dissatisfaction with  the National
Academy's analysis of the hot particle hypothesis, it  does  not believe
that a recapitulation of this issue is necessary to insure  that  the
estimates of lung cancer risk used in the preparation  of  these Guides
are adequately conservative.       *
17.  Nuclear Safety Associates

     In a technical point, the dose-risk relation  for  inhaled  transu-
ranics was based on the product of an annual average dose  rate to
pulmonary lung tissue of one millirad per year  and the unit  risk
appropriate,for bronchial cancers (i.e., in bronchial  tissue).  The
dose and the risk estimates were not to the same tissue.   The  dose to
pulmonary tissue was calculated by the EPA to be about 20  times higher
than the tracheobronchial dose.  However, in Hiroshima survivors, the
significant increases in lung cancer occurred in the bronchi rather
than in the pulmonary region.  In short, a lung dose, rate  limit based
on the product of the region receiving the highest dose and  the risk
to a different region which has the highest risk per unit  dose would
not be realistic and would not provide protection  corresponding to the
intended maximium level of risk.  Instead, a lung  dose rate  limit set
on this basis would appear to be much more restrictive than  intended.

     Staff Response - This information was included in Annex III and.
the point made is :recognized by the Agency.  See the reply to  comment
16.            ,                             .                       -
18.  Jefferson County Health Department

     ...I believe that the estimated risk  is understated.. .much more
than a "sma,il fraction" of plutonium retained  in  the  lung  is
translocated to the bone.  (The Guide should be reduced because of  the
factor of 3 uncertainty in Annex III).   (Page  60948 - F.R.)

     Staff Response - The Agency agrees  that characterizing this
fraction as small is incorrect.  In accordance with the ICRP  task
group lung model, the risk estimates in  Annex  III are based on the
assumption that about 20 percent of the  material  initially deposited
in the lung is translocated to other organs.   However, the Agency does
npt agree that ,the degree of uncertainty in the estimated  risks are a
reasonable basis for.reducing the proposed Guides since the degree  of
uncertainty in the risk estimates, as well as  the conservative nature
of the exposure situationg, (e.g., lifetime residency, and the       .
conservatism in the risk modeling) were  considered in the  development
of these Guides.       !

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                                     19

 19.  Jefferson County Health Department

      The dose limits are higher  than those  promulgated  by EPA for
 drinking water.                                                      "

      Staff Response - The comment seems  to  imply  that the maximum
 contaminant limits for radioactivity in  drinking  water  replace Federal
 Radiation Protection Guides for  exposures to the  general population.
 They do not; the drinking water  regulations are specific on this point
 (41 ER. 28409).  The drinking water  limits are for a single pathway,
 finished drinking water.  The proposed Guides for transuranium
 elements in the environment include the  doses due to inhalation and
 food pathways and are limited to contamination by transuranium
 elements.

      The proposed guides provide for a 3 mrad annual dose limit for
 bone tissue after lifetime exposure.  The drinking water regulations
 limit the annual dose rate to bone tissue due to alpha particles from
 radium-226 to 15 mrad per year (EPA-570/9-76-003, National Interim
 Primary Drinking Water Regulations).


 20.   Jefferson County Health Department

      In addition to  resuspension of plutonium from surface dust,  we
 must also consider the release of particulate to plutonium from
 plutonium-processing plants.   These particles are for the most less
 than five microns (micrometers)  in size and large numbers are released
 at  times.  Eight days after  a fire at Rocky Flats in 1957,  as many as
 125  million of such  five micron particles of their equivalent were
 released in a single day from a stack  (3).   A two micron particle of
 plutonium oxide,  if  inhaled,  would produce  a dosage  of over  two
 millirem to the  lung,  96  millirem,to the  tracheobronchial lymph nodes,
 and^six millirem to  bone  (4).  A particle five microns in size could
 be inhaled  and retained  and  produce  a dose  tq  about  40 millirem to  the
 lung,  1,700 millirem to  the  tracheobronchial lymph nodes, over 130
 millirem to the  bone, ,,50  millirem to the  liver, . eight millirem to  the
 kidney,  and two millirem  to  the  gonads, where a'pattern  of
 microdeposition  of plutonium would give a proportionately greater
 effect  than would be  expected.   Particles of this  size,  of course,  are
 microscopic in size  and of the  same  order of size  as bacteria, and  may
 be blown^by, the wind  for  great distances. A single particle  only  two :
 microns  in  size,  if  inhaled  and  retained, will produce a dosage
 exceeding the EPA 4 millirem maximum annual  dose  (4)..

     Staff  Response - The Guidance does not  appjly  to routine,
 controlled  emissions.  The dose  estimates used by  Dr. Johnson  are
 taken from  a 1974 paper by Dr. N. Barr.   Dr. Barr  presented his
 estimates for 0.3 urn AMAD (0.1 urn Diameter)  particle's as either Class
Y or Class W compounds.  Dr. Johnson has  combined  the estimates for
                                 118

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                                   20

Class Y and Class W, an impermissible aggregation, .and then used these
dose estimates for a 5 urn (actual, diameter) particle.  Thus, his
soluble/insoluble particles overestimate dose by a "factor of about 4
due to change in particle diameter.  Moreover, in his analysis they
are assumed to continue to irradiate lung and lymph nodes even after
they dissolve and are deposited in the rest of the body.  The
reference to the 4 mrem maximum contaminant limit for drinking water
is inappropriate.  See response to comment 19.
21.  Jefferson County Health Department

     The proposed guidelines state that persons with a continuous
exposure to one millirad of plutonium-239 would have less  than  one
chance per million per year and less than 100  chances per  million in a
lifetime of dying of cancer.  One millirad  of  plutonium-239  is
equivalent of 20 millirem in lung, with correspondingly  larger  values
in other organs.  I estimate that there will be a  total  increase of
all cancers of perhaps 0.06 to 0.2% over a  period  of seventy years  due
to this exposure, or 600 to 2,000 excess deaths from cancer  per
million persons (4).  In addition, there will  be an increase in the
incidence of all genetic dieases by 0.1%, and  ill  health related to
chromosome mutation by 0.6% for all succeeding generations.   I  think
that in making such estimates  that it  is risky to  rule out
potentiating factors such as the effect of  smoking on asbestos  workers
and uranium miners.  Such potentiating effects may be expected.

     Staff Response - The author of the comment appears  to have
misinterpreted the 1972 NAS-BEIR Report.  The  BEIR Report  increase  in
cancer was calculated on the basis of  chronic-unifbrm total  body
irradiation and reflected an increased incidence in cancer mortality,
not an increased incidence of mortality due to all causes.  A 1%
increase  in cancer mortality is about  a 0.2%  increase in mortality
from all  causes.  Therefore, the commentor's  results  are five times
greater  than a correct evaluation.

    ' In  addition,  developing risk estimates for individual organs
requires  development  of  risk estimates similar to  those  in BEIR Tables
3-3 and  3-4 for  each  organ.  The BEIR  Report  risk  estimates  for total
body dose cannot be  applied.   Mor'eover, even  if  such  an  approach were
taken,  the risk  estimates would be  too high by a  factor  of 2 or more
since  the dose  to lung  is  equilibrium  before  other organ doses for
Class Y  compounds.   This  factor was  neglected also.                  '

     In either  case  his  calculation  of .mortality  is  wrong.  The
increase in  the  BEIR Report  is given as  a percent  increase in cancer
mortality, not  total mortality.  Assuming an increase of 0.06% to  0.2%
in the  total  cancer  mortality,  yields, per million persons at risk, an
additional 108  to  360 cancer  deaths, not  the 600  to  2000 calculated by
                                   119

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                                    21

 Dr.  Johnson.   Further adjustments for differences in dose rates and
 total doses for specific organs would yield estimated excess cancer
 mortality close to that developed by the Agency in Appendix III of the
 proposed guides.

      A similar situation holds for Johnson's estimates of genetic
 risk.  If the BEIR Report genetic risk estimates are used, the 0.1%
 increase in incidence of genetic diseases and 0.6% in ill health
 calculated by Dr.  Johnson imply each parent received an average of one
 rem  gonadal dose  between birth and age 30.   The gonadal dose estimated
 by Dr.  Johnson appears to be 2 thousandths  of a rem or less per
 person.   The  genetic risk, thus, appears to be overstated by a factor
 of 500  or more.

      The commentor's final comment,  that potentiators such as smoking
 should  not be discounted, is valid.   Since  lung risk estimates are
 derived primarily  from uranium miners studies and the uranium miners
 smoke about as much as U.S.  males of the same age,  the synergism of
 smoking is already included  in the risk estimate.   The effects .of any
 unidentified  potentiators are also included in the  risk estimates to
 the  extent that the exposure of uranium miners is  equivalent to that
 of the U.S. population.   In  the absence of  any other data no further
 adjustment of risk estimates can be  made.
22.  Jefferson County Health Department

     In any  discussion  of  dose  limits  for  plutonium or  other
transuranium elements,  new evidence  relative  to  the adequacy,of  such
dose limits  must be  considered.  A recent  report  of a study of
plutonium workers at Rocky Flats found a significant increase in
chromsome abnormalities in the  blood lymphocytes  of plutonium workers
who had received only 1% to 10% of the body burden  of plutonium
permitted by the present federal guidelines (5).  This  is very
significant, because it indicates that the present  guidelines are
inadequate and are not  providing protection for  plutonium workers.
Existing federal guidelines to  provide radiation  protection from
plutonium should be  decreased by at  least a factor  of 100 in order  to
achieve a level where no observable  effects are noted.  A reduction in
the maximum  permissible level of plutonium for workers  should result
in a corresponding reduction in the  radiation protection guides  for
the general  public.  Recent reports  by Dr. Karl Morgan  and Dr. Myers
also suggest that the present Federal  guidelines  are too high by a
factor of about 200  or more (6,7).

     Staff Response - The Agency is  familiar with Dr. Brandom's work
on peripheral lymphocyte cytogenetics, and at present agrees with Dr.
Brandom's position of not  drawing any  hereditary or clinical
implications from the data.  Chromosome aberrations have been observed
                                  120

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                                   22
after many types of physical or chemical insults, but as yet,, there is
             .               o
which will, as necessary, be incorporated  into Federal  guidance.
     However, it should be noted  that  the  lowest bone marrow doses  to
which these industrial workers  are  being exposed and where  these
effects  are seen is  about  50 times  greater than would occur at the
proposed guides.
     The Agency ha,
                                                                    ,
 m» properly compared, as done in the referenced paper, the Agency s
 toS .rSHrttaate differed from Dr. Morgan's estimate by a factor of
 3 or less.                              .  . ,
 23.  Jefferson County Health Department.
      The report notes that "unlike radium-226, which  is  distributed
 throughout Pth^ bone volume following Aong-term -gest^,. plj™ »
 nrpferentially deposited  and  retained  near bone  surfaces .  As mucn  as
 §5% to ?0% of Plutonium has been  shown to be  retained on osteogenic
 cells!  Americium  and curium  are  also  retained on bone surfaces   and
 so, more prone to  be a cause  of radiogenic bone  carcinomas than  is
 radium.

       Staff Response - In  assessing the bone  cancer risk, the,Agency
 assumed  that plutonium, americium and curium are retained on bone
 surfaces,  and the  risks have  been calculated accordingly.

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                                     23
 24.  Department of Energy

      As a general comment, the EPA could have more justifiably
 employed generally accepted dosimetric and risk estimation  techniques
 and parameters, such as those recommended by ICRP, NCRP, and  in  the
 BEIR and UNSCEAR Reports.  Where changes from these established
 procedures seemed essential, because of important new information,
 these changes should have been clearly justified.  This was not  done.
 In fact, it is impossible to check any of the detailed models employed
 or calculations made in arriving at the numerical values tabulated in
 Annex III and Annex IV.  These are referenced to unpublished EPA
 documents, and were calculated by a computer code that is similarly
 undocumented.                                                       ,

      With the above very serious reservation, it must be acknowledged
 that the numerical conclusions relative to dosimetry and associated
 risk appear to be not grossly unreasonable,  though sometimes stated in
 a manner that exaggerates the confidence one is entitled to place in
 such numbers.   A few of the more serious shortcomings of the Proposed
 Guidance,  in this area, are discussed below.

 Ingestion Route;   Dose relationships  involving transuranic
 concentrations in soil or air are developed  only for the inhalation
 route.   It is  stated  in many places  that  the  inhalation  route  is  most
 important,  and implied that if it is  controlled,  one  can ignore
 ingestion;  however,  in some other places  it  is  stated  that  ingestion
 may  need to be considered.   The  conclusion that  ingestion is
 relatively unimportant apparently arose from  an  unjustified assumption
 that environmental  transuranics  were  always very  insoluble,  and from
 lack of  adequate  consideration of external transuranic contamination
 food.  This  conclusion was  also  supported by  the  use of  a lung cancer
 risk factor  larger  than is  customarily  assumed and a bone cancer  risk
 factor smaller than is  customarily assumed.   Although  it  does  not
 appear likely  that  ingestion will be  a  more important route  than
 inhalation  for most exposed persons,  it is not all unlikely  that  some
 "critical segment" may  receive a  larger dose  from  ingested
 transuranics than it  receives  from inhalation.  It would  seem
 incumbent upon the EPA  to evaluate the  total  pathway from soil to
 cancer for the ingestion route,  to the  same degree that  this has  been
 done for the inhalation route.  The dosimetric behavior of  such Class
W materials should be given consideration in  this Guidance.
Presently, this consideration consists  only of a reference to an
 unpublished report.  Appropriate consideration Class W compounds  would
 increase the relative significance of bone and liver cancers and
genetic effects, at the expense of lung cancers.
                               122

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                                  24      •"-

Gonad Dosimetry:  The treatment of gonad dosimetry and risk is
considered to be inadequate.  The exact parameters employed for
dosimetric calculations are not defined in the Proposed Guidance, but
it is implied that the dose is taken to be half that calculated  for
bone.  This assumption seems to result from using the estimated
average dose to ovaries, and 2 to 3 times the estimated average  dos?
to testes.  The increase weighting of the testes dose is  justified by
autoradiographic studies in mice  that showed preferential deposition
of plutonium near spermatogonial  stem cells.  Recent studies  indicate,
however, that differences  in testes anatomy between mouse and man make
it unlikely that the  same  kind of non-uniform deposition  observed  in.
the mouse would affect the dose  to spermatpgonial  stem  cells  in  man,
DOE Doc. LF-56, pp. ,389-403  (1976).  There  is also .evidence  that
irradiation of;  the mouse ovary  is virtually without effect.   It  would
therefore appear that the  estimates of genetic  effect  in  the  proposed
Guidance are  too high by a factor of about  five.

Canper  Risk Estimates:  Because  of unavailable  references, it is
impossible  to reconstruct  the  total basis on  which risk estimates  were
derived  The estimate of  bone  cancer  risk was  quite  straightforwardly
based on  the  human  224Ra, data,  and  though one may quibble with the
validity of  small  corrections  applied  to the  original  observations-pi.
Spiess  and Mays,  the number arrived  at is probably better, for
 transuranics, than the considerably  higher estimates  of  the BEIR
Report  and  ICRP Publication 26,   It  is not at all clear how the lung•.
 cancer  risk was derived.   The result,  however,  reflects  a greater risk
 than has  usually been assumed for lung irradiation.  This combination
 of a higher than usually assumed factor for lung cancer,  and a lower
 than usually assumed factor for bone cancer,  results in  the prediction
 of an unexpectedly high ratio of lung to bone cancers.   This may be as
 good as any other estimate, but, because it is different, requires
 justification that is not given in the Proposed Guidance.

 Uncertainty of Risk Estimates;  The general tone of Appendix III
 implies a certainty with  regard  to risk estimates which  is unjustified
 and  could be seriously misleading to responsible officials and  to the
 general reader, 'unaware of the uncertainty of many of  the assumptions
 employed.  This Annex ignores express warnings of BEIR Committee and,
 NCRP,  concerning the need to qualify such estimates with a clear
 statement of inherent uncertainties.  The BEIR Report  states
 that"  ..explicit explanation and qualification of  the  assumptions and
 procedures involved  in such risk.estimates are called  for to prevent
 their  acceptance as  scientific  dogma".   The Proposed Guidance  states^
 on p-3 of Annex III,  "that  for  highly ionizing radiation such  as .alpha
 particles from plutonium  the  linear non-threshold  hypothesis is
 unlikely to  overestimate  the actual risks"  (emphasis  supplied;,, .  The
 highest and  lowest  of BEIR estimates  are presented as  a   range
  implying  that  the  real number  will  fall somewhere  between these
                                   123

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                                   25
  numbers.   Derived risk estimates are often given to 3 significant
                 °Uld -eem V6ry imP°rtant ^ a8document such as this,
                 a8enc^s and  the public not be mislead.  This is not a
           of  conservatism or lack of conservatism.   The risks from
       th  nr/"7  1W  1?Vei\°f radia£i°n •« --Ply -t understood
       the precision implied  by  many  statements in this Proposed
  Guidance.                                                 r

       These general  comments  are  abridged below in  the staff response.

       Staff Response -  "EPA  could have  employed  generally  accepted  dose
  and risk estimation techniques and  parameters."         I,

  rnmm...JheT^is.for this comment is not  clear.  ICRP Task  Group and
  Committee II dosimetry models were used  throughout Annex  III.  ?he
  essentials  of the life table risk analysis used by the  1972 NAS-BEIR
  Committee and in Annex III and IV are  laid out on pages 171-173 of th*
  1972 NAS-BEIR Report.   Estimates of the lung cancer risk  are taken
  STi^S0" thS  19?2 MS-BEIR ReP°«s and the 1976 MS Report
  T"ea: S  E-ffects of Alpha-emmitting Particles in the Respiratory
  Tract.    Because the Agency's assessment of bone and liver cancer risk
  are  not  found in the 1972 NAS-BEIR Report (where liver cancer was not
  considered  and the effects of bone  surface seekers  given insufficient

  ^rHST0-""' £8enCy ^^"^  ltS OWn risk "timates for these
  cancers  following  the methodology described in the  1972 NAS-BEIR
  Report.  Over six  pages in Annex  III were used to document the
  information used to develop  the risk estimates for  liver and bone
 Aea£«*  f I  Agency has acknowledged in Annex III that the National
 Academy of Sciences' ongoing review  of radiation health effects
             S" pr°Vide.f more CUrrent "Cation  of the risk due to
             than was available  at the  time the  proposed  guidance  was
            When the new BEIR Report  is  completed, ?he  Agfncy wUl
             1*  eStimates  in  the ProP°^  guides  to  detfrmine  if
             changes are needed.

 *™ ,Dose.Jela5ionshiPs applicable to the  ingestion of transuranics
 are described in Section 3.4.4., PP. 10-21 of Annex III.  Table A 3-6
 gives the dose to various organs due to the ingestion of four
 transuranics and Table  A 3-7  for six.  Table A 3-8 gives gonadal doses
 due to ingestion for six transuranics and Table A 3-9 HsL do^e due
 to  chronic ingestion by infants.

      No basis  for the DOE assertion that "Transuranics other than
 Plutonium are  now considered  to  behave as Class W materials" is

 S£  *f-6V     f Xt haS been rum°red that the ICRP  is considering the
 classification of some  transuranics  in the W category,  it has been thl
Agency's  experience that ICRP's  published reports can diffe?
P,1;f^fanJlyi5r0m  hea"ay about their contents.   Obviously Federal
Guidance  should  not be based  on  hearsay.  The  dose and  risk for Class
W compounds are  discussed  in  Section  6  where it  is shown that the  risk
prepared

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                                  26
due to the inhalation of Class W compounds at the proposed dose rate
limit is comparable to that for Class Y compounds.
25.  Department of Energy

     Since there have been many recent and extensive published reviews
and collections of information on the biological properties and
effects of the transuranium elements, it seems unncessary to provide a
single reference to an unpublished document,  (p-1, lines 13-15)

     Staff Response - The document referred to contains 30 pages and
cites over sixty publications in the sections providing information on
biological properties and effects.  Publication of  this material
separately was the result of an editorial decision  favoring a short??
Guidance document.  Xerox reproductions of this material were provided
to the commentors in 1977.                             -
26.  Department of Energy

     The implication  that we know  little  about  transuranics  in gonads
is misleading.  The fraction deposited  in gonads  is  somewhat uncertain
only because  it is so small as  to  be  difficult  to measure  in the
general population,   (p-1,  line 9)

     Staff Response - The available data  is  neither  extensive nor
persuasive.   Animal data shows  such a wide range  of  inter-species
variability that  its  application to man is tenuous.   Variability  in
the human data  is in  part due to measurement difficulties.   Moreover,
there  is no data  on distribution patterns in human gonads  and very
sparce data for animals.  These data  are  reviewed in the guidance
document.
 27.   Department  of Defense

      The  literature abounds with information on the biological
 properties  of transuranium elements;  therefore, why reference an
 unpublished review?  Is it because it is an in-house pub?
 (p-1, p-2)

      Staff  Response - See response to comment 25.
 28.   Department of Energy

      The statement in Annex III that refers to the "procedure used by
 the  BEIR Committee in arriving at its best estimate of radiation
 risV.   To refer to anything from the BEIR Report as a "best estimate"
                                 125

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                                  27

seems contrary  to  the spirit of  that  report, which was,  in most
instances, careful  to qualify  its  estimates as  "fraught  with
uncertainty".   Only in  their Summary  and Recommendations did  they
quote a "most likely" estimate,  which is a statistical "most  likely",
assuming the accuracy of  their models (an assumption  they were
elsewhere careful  to avoid).
(p-2, lines 19-22)

     Staff Response - The phrase "most  likely estimate"  not "best
estimate" is correct.   It appears  in  at least four places in  the 1972
BEIR Report, (pages 90, 91, and  168)  where it is used in the  sense
outlined in the comment,  and also  in  the "Summary and
Recommendations",  (page 2).  In  the latter case it means the
Committee's "best"  guess given the range of values that  can be
estimated using the various models and risk coefficients given in the
report.  It is clear that the  Committee did not believe  their "most
likely" estimate was very accurate, nor does the Agency  believe so.
Rather, the point of the cited sentence was to indicate  that  the
method of averaging used by the  Agency results in numerical agreement
with those labeled as "most likely" by the Committee.
29.  Department of Defense

     The BEIR Committee Report takes great care in explaining what
their "best estimates" mean.  This document should at least
acknowledge that there are qualifications surrounding the estimates
and not present it as scientific fact,  (p-1, p-2)

     Staff Response - See response to comment 28.
30.  Department of Energy

     It is not clear what is referred to by the phrase "risk estimates
listed below",  (p-3, Line 6)

     Staff Response - The phrase refers to risk estimates in Annex III.


31.  Department of Defense

     What risk estimates below?  Those being derived by EPA, those
taken from elsewhere or what?  Also, is any model "appropriate"?
(p-3, line-4)

     Staff Response - See response to comment 32.
                                106

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 32.   Department of Energy        ,   ;       ,  .

      The phase, "which of these models is appropriate", implies  that
 one ;of them is appropriate, which does not necessarily follow.
 (p-3, line, 7)      ,.'.:..                          .          -  ,,. ,,

      Staff Response - The Agency disagrees.  There is a growing  body
 of evidence that the absolute risk model is applicable to
 radiation-induced leukemia (and ..perhaps, bone cancer),-while models
 which,-incorporate, the increased risk of cancer with advancing age :are
 a better choice for such common cancers as breast and lung cancer.•-,-•
 Ref:   The Latent,Period of Radiogenic Cancers Occurring Among Japanese
 A-Bomb Survivors,   ,C. E, Land and J. E. Norman, IAEA Late Effects
"Symposium, Mar eh,, 13, 1977 i Vienna. ,«   ...
 33»   Department; of Energy            ,.'..  .

  .If,  as  the agency recognizes in the latter part,of this sentence,
 the  risks are based upon a hypothesis, by definition the risks are
 hypothetical.

      The  statement "that linear non-threshold., hypothesis is unlikely
 to overestimate the actual risks", implies a certainty with"regard to
 risk estimates,that was not shared by the authors of the BEIR Report,
 who  cautioned that "the foregoing estimates ..of mortality from    . ., -
 radiation exposure may be -too.high, ,or too. low, for. a.varietyspf
 reasons",  (p-3, lines 14-17)               •
 35.   Department of Defense

      This  entire paragraph is a distortion.  Contrary to the statement
 that  "the  agency dose not consider the risks due to ionizing radiation
 hypothetical...",  the fact remains that they are hypothetical as
 estimated  by  the Agency.   (p-3, line 2)     ;                   „-.,.-.

      Staff Response - Due to ou,r 
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                                  29
35.  Department of Energy

     The reasoning of  this paragraph  is  difficult  to  follow.   It  seems
to be justifying an increased  dose  to  children  on  the basis of an
insignificant change in  lifetime risk, but  neither the  increased  dose
to the child, nor the  effect on lifetime risk,  is  adequately  defined.
Since the basic Guidance is terms of  dose per year, not  risk,  the risk
argument is technically  irrelevant.   (p-4,  line 17 to p-5,  line-3)

     Staff Response -  Section  1, pages 17,  23 and  particularly the
footnote on page 24 indicate clearly  that this  numerical Guidance
applies to adult organ doses.  No attempt is made  in  the Guides to
justify the risk to children.  Rather, the  increased dose and  risk  to
children has been: considered in the estimates of,the:risk due  to  ,
lifetime exposure.  The  pulmonary dose to children is;about one and a
half times greater than  that to adults.   This may  increase  the  ,;
lifetime risk by about ten percent.              . ...  ,

36.  Department of Energy

     The "logarithmic  averaging" requires further  description  and
justification.  To imply that  other conservative assumptions will
balance a nonconservative bias, without  identifying or quantifying
these assumptions, confuses the analysis, (p. 5, lines  17-22).

     Staff Response —  The Agency does not endorse  the exclusive use of
either the largest or  smallest risk values  that  can be generated  with
the BEIR risk models.  The Agency's use  of  logarithemic  averaging of
the various 1972 BEIR  risk estimates yields numerical results  that
agree with the BEIR Committee's "most likely" estimates.  However, as
stated in the Guidance document such a procedure weighs  absolute  risk
estimates somewhat more heavily than  the  relative  risk estimates.  The
degree of bias this introduces is small  compared to.the  uncertainties
in the risk estimates, e.g., for the case of lung  cancer mortality,
about ten percent.  No attempt was made  to  offset  indeterminate
quantities.
37.  Jefferson County Health Department                 ,

     The dose and risk to health due to inhalation and ingestion of
transuranium nuclides.  On page 4 there is an inadequate explanation
for the choice of the term "rad" in place of the more commonly used
"rem".  In a few years the dosage from.gamma radiation from americium
can be significant harzard in areas contaminated with transuranium
element.  There is adequate justification to use the more conventional
term, "rem" in order to reduce radiation effects to a common
denominator.  Consequently, I recommend that the terms rad or millirad
be converted to rem and millirem throughout this document.
                                 128

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                                  30
     Staff Response - The rem  is not  an  appropriate  unit  for  risk
analyses since RBE and quality factors differ  for  various  biological
end points, see response to comment .92.
38,  Jefferson County Health Department

     In the last paragraph on page 4,  the  report  states,  "this
provides a conservative estimate of childhood  dose  since  deposition
and retention in the lung should be less for children  due to  their
smaller lung area".  This is probably  not  correct,  because of the
higher metabolic rate and the greater  physical activity of children.
In'addition, children spend much more  time outdoors and are breathing
air more near the surface of the soil  than are adults.  On page  5 it
is!noted that the Agency has chosen a  less conservative relative risk
model for children rather than  the more conservative model which
assumes children are ten times  more sensitive  to  radiation than  are
adults.                                                 .

     Staff Response - The Agency utilized  data on age  specific minute
volume, airway dimensions, and  lung surface area  to calculate the
maximum that pulmonary deposition as a function of  age.   Deposition
peaks around age 10.  At this peak period, deposition  per unit area is
about twice that in infants and adults.  The Agency's-use of  this
value is likely to be slightly  conservative since this occurs for only
a  few years during which the body is growing rapidlyi  Moreover, the
contribution to lung dose and body burden  from material inhaled  during
this period would probably be reduced  by faster clearance, (the
distance material travels to be cleared is shorter).  Unfortunately
these facts were not clearly stated in the paragraph.
39.  Department of Energy

     The triple negative in this sentence makes  it  very  confusing.
(p-5, lines 20-22)

     Staff Response — The sentence should read "It  is  unlikely  that
the true risks are underestimates."
40.  .Department of Energy
                      .   -                                     t
     The reasons given for "expecting"  that  inhalation will  be  "the
most important pathway" are vague and insufficient.  The  conclusion,
itself, will be questioned by some,  (p-6, lines  2-15)

     Staff Response - The amount of food and water coming from
contaminated land and ingested by those inhabiting this area could be

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                                   31

highly variable and certainly circumstances  could  arise where  the
ingestion pathway is predominant,  at  least for a limited  time.
Nevertheless, breathing on  the part of  inhabitants  is  inevitable and
contaminated air is not as  readily replaced  as food and drinking water.

^•1*  Department of Defense

     The reasons given do not support the conclusions  stated.
(p-6, para. 1)                                                       ,

     Staff Response - See response to comment 40.      \
42.  Department of Energy '

     These statements are correct only for a highly insoluble  form of
inhaled plutonium.  Dose to  liver and bone, relative to lung,  and the
temporal pattern of this dose, will vary widely depending on the
nature of the inhaled material.  The lack of consideration of  anything
other than very insoluble forms is a consistent weakness of this Annex.
(p-7> lines 10-14)

     Staff Response - The statement is true for Class Y compounds.
Class W compounds are discussed in Section 6.          ...
43.  Department of Energy

         Again, the emphasis is on "highly insoluble transuranics,"
with'no mention of more soluble transuranics.  In fact, 239puQ2 is
probably the only compound that would qualify as a /'highly insoluble
trahsuranic" in the context of this sentence, and even this may be
questionable.  (p-7, line 25 to p-8, line-3)

     Staff Response - See response to comment 42.
44.  Department of Defense

     It is not clear that administrative controls have any -
relationship with chosing the specific model.  It may he fortuitous.
(p-7, line 16)                    ,

     Staff Response - (The comment is unclear).
45.  Jefferson County Health Department

     In paragraph two on page seven, the report states "the uptake by
plants is relatively small, and most animals, including humans, have a
                                   130

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                               ---•-"32      •,,:.

high discrimination factor against  transfer  of these elements into the
body tissues".  However, some plants,  such as  algae  and seaweed,  have
the ability to concentrate plutonium,  presumably in  a form that can be
assimilated by animals.  Chelating  agents present in soils over a
period of time may make the plutonium  oxide  in soil  available for
uptake by both plant and animals  to a  greater  extent.   (P-7)

     Staff Response - The increased availability of  transuransics
after a period of time is covered by the Agency's use of increased  ,
absorption by a factor of 5 to 50 for  biologically incorporated
elements as compared to elemental forms.

     The Guidance is based on a dose limit (rather than a maximum
permissible concentration) and is therefore  independent of the form
encountered which must be considered on a site specific basis.
46.  Department of Energy                                        -  •  -,

    .Should "reference 5" read "reference^"?   Fig.  A 3-2 seems to be
from (5), but Table A 3-1 is from  (4),  and  they are  not  completely
consistent, as noted later.  (p-9,  line-11)

     Staff Response - Yes.                         .   "     r     i
47 .  Department of Energy

         Justification.and/or references  should  be given for the
contention that environmental plutonium and  other  transuranics "are
likely to"be in the oxide or hydroxide form."  There  is  considerable
recent evidence to the contrary, particularly  for  the transplutonium ..„
elements.  This becomes important  for estimating doses due ,to
ingestion and for the determination of the ICRP  lung  dose.
(p-9, lines 15-18)

     Staff Response - See Section  3.2, Annex II, response to comment 2.
48.  Department of Defense

     What is evidence for saying  environmental  sources  of^pl
are likely to be "in oxide or hydroxide  form"?   In  general,  all  the
material here and preceeding seems  to be biased toward  insoluble
transuranics with little regard for  soluble  forms.       •"---  -
(p-9, line 15)
                                   •• • •- -, •'.  ,'  .' ;.,': .  -•  :...  •  r. •  •<••' .- I    t'
     Staff Response - See Section 3^2, Annex II,  response to comment 2.

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                                  33
49.  Department of Defense
     Same  comment  applies here with  regard  to  unavailability  of
reference  as was pertinent  for the reference on  the PAID  code.  One
must accept the dose  estimates calculated by EPA.   (p-9,  line 22)

     Staff Response - The PAID code  has been documented and published
as EPA document, Technical  Note ORP/CSD-77-4.  See also response to
comment 52.
50.  Jefferson County Health Department               .           .  ;

     On page nine, the report notes that insoluble  actinides have an
estimated biological half-life  in pulmonary  tissue  of.500 days. .
Plutonium and the other actinides leave the  lung by the  transport of  '
particulate materials into the  lymphatic system to  the lymph nodes, or
by elevation up the tracheobronchial  tree, or by dissolution into the
blood stream.  It must be noted  that  the particle size of the
respirable fraction of these particles is in the same order as
bacteria, which likewise are .able to  be transported about the body;
The estimated biological half-life of plutonium in  the liver is
assumed to be 40 years and for bone,  100 years.  (p-9)

     Staff Response - Although both bacteria and respirable particles
can be transported to various body organs via blood, direct comparison
is inappropriate because of the higher density of plutonium and
differences in physiological transport mechanisms.
51.  Department of Energy

            "only retention in the pulmonary region" receives
attention.  The sentence is incorrect except perhaps, for highly
insoluble 239Pu02-  (p-10, lines 3-5)

     Staff Response - Perhaps the sentence is not clear.  This
paragraph is comparing the dose to various compartments within the
lung, not the dose to the pulmonary lung relative to other organs;  In
this context, the statement applies equally well to the more soluble
Class W compounds.  The sentence would be more clear if written;  "In
assessing the lung dose and risk due to the inhalation of Class Y
transuranium elements, only retention in the pulmonary region is of
primary importance."
52.  Department of Energy

     The unavailability of the PAID code precludes any possibility of
checking dosimetric calculations,  (p-10, lines 18-21)
                                 132

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                                  ""'34'    ,.  -•*".;...   .;.....-.. . •.

     Staff Response - The PAID code was made  available  to  DOE
reviewers in January of 1978.  Published  references  cited  in the  text
Annex, (7,8), contain essentially the same  derivations  as  those given
in the -PAID; documentation.  The extension of  these derivations to
include the dose due to the daughter products of  initially deposited
parent radionuclides is straightforward.
53.  Jefferson County Health Department

     The last paragraph on page  ten notes  that  the  ICRP model  is  based
on ambiguous equations, but in turn is used  to  calculate  the annual
dose rates resulting from inhalation of  isotopes  of plutpnium,
americium and curium for a number of particle sizes.   This  ambiguity
is important to note, since such calculated  doses are  often presented
with an air of.unwarranted precision.  (P-10)

     Staff Response  - The statement was apparently misread.  The ICRP
Report does not provide unambiguous equations.  The PAID  code  for
calculating doses and dose rates does use  documented equations  and a
well-de-fined model based on the  ICRP Task  Group Report (Reference 5,
Annex III).  However, the reference to "unwarranted precision"  is
appropriate in view, of possible  differences  between actual  exposures
and the results predicted by the task group  lung  model.
54.  Jefferson -County Health Department

     On page eleven, the  last  paragraph,  the  report  states that the
high dose rate to the tracheobronchial lymph  nodes  is  "not believed to
be an important consideration  in  estimating risk" because of animal
studies.  I would question this assumption, in view  of the length of
life of man ;in relation to the length of  the  animal; study periods.
(P-ll)

     Staff Response - Although only  the statement that "the lifespan
animal studies showing that the frequency of  respiratory lymph node
cancer is negligible compared  to  other cancers caused  by transuranics"
was referenced in the ORP support document, there is also human data.;
Respiratory lymph node cancers have  not been  reported  in uranium or
other1 miners who have deposited inhaled uranium ore  dust.  Neither has
lymph node cancer been associated with Thorotrast exposure even though
Thorotrast does deposit in lymph  nodes.   There is no evidence reported
of risk related to deposition  of  radioactive  material  in lymph nodes
at this time in either man or  animals.                             •*
55.  Department of Energy

     The  section heading refers  to  the  dose.to  the total body,  but
there is  nothing in  the section  about  total  body dose,   (p-12,  line-1)
                                 IBB

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                                   35

      Staff Response - Total body doses are discussed only for the case
 of ingestion (Table 6-6) and should have been omitted from the heading
 referred to.
 56.  Department of Energy

      A reference should be given for the statement that half life for
 transuranics in gonads may be longer than 100 years.  It might be
 better simply to state that the amount present is too small to study
 the rate of release.   (p-12, line-10)

      Staff Response - Fish, et al., B. R. Fish, G. W. Keilholtz, W.  S.
 Synder and S. D. Swisher, Calculation of Dose Due to Accidentally
 Released Plutonium from an LMFBR.  ORNL-NSIC-74, USAEC, Oak Ridge, 1972
 reference an estimate of infinite  retention in gonads.  They do not
 mention that the amount is too small to study.

        Moreover, studies by D.  M.  Taylor reported in "The Uptake,
 Retention and Distribution of Plutonium-239 in Rat Gonads", Health
 Physics 32^:29-31 (1977) indicate a variety of transuranics show no
 appreciable loss from the gonads.   Again no problems in measurement
 were  noted.
57.  Department  of Energy

     Again,  the  Class Y .assumption  is  unjustified  for  amerieium and
curium.  Why is  239pu specified  as  the oxide,  while  other  compound
forms are unspecified?  (p-12, lines 18-21)

     These calculations apparently  assume  (one cannot  be sure without
Ref. 6)'a constant concentration of transuranics in  air over the 70
years of exposure.  This does not appear appropriate,,  particularly for
the shorter-lived transuranics,  since  the  concern  is for single event
contamination of soil.

     Staff Response - All actinides (including amerieium and curium)
are currently classified by ICRP as Class Y if in  the  oxide or  dioxide
form.                                             :

     The chemical form is specified for Pu-239  oxide because a  portion
of the dose  to liver and bone due to inhalation depends on the
transgut transfer of material swallowed after  the  inhaled material is
transported up the bronchial tree.  For the Pu-239 calculation,  the
gut transfer for the oxide forms (0.0001) was  used since it is  the
case most likely to be encountered in  the general  environment.  Doses
for amerieium, curium and high specific activity plutonium oxides were
calculated for a gut transfer of 0.001 as in Table A 3-5 of Annex III.
                                134

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                                  36

                               - • ?•'-"-"        ~-X-,.-- .        «;
     The  assumed  duration of the  chronic exposure is for a lifetime.
Tables A  2-3  and  A 3-3  are clearly  labeled "Duration of'Exposure" and
go  up to  70 years.   It  is likely  but  not inevitable that the
concentration of  shorter  lived transuranics in air will vary with the
half life of  the  radionuclide  since the  long term resuspension rate is
likely to be  constant.  The Agency  agrees that in many cases
radioactive decay will  reduce  exposures  from the shorter half life
transuranics.                       .

     Table A  3-4  gives  concentrations based on a constant annual''   r
intake.   However,  Table A 3-4  is  not  the Guide, and need not be used ^
where it  can  be shown,  on a site  specific basis, that  the pulmonary
dose, rate of  1 mrad per year is not exceeded.           -
58.  Department of Energy                            :  ;  .        -,

     The statement probably  is not  true.  Much  of  the  liver  deposit
may derive, from particulate material  transferred via  lymphatics.
(p-12, line-25 ,to p-13,  line 3),                       ;     ,        .•

     Staff Response: - The  sentence,  is not well  worded.  A  better
sentence would be: "Almost all of the dose  to liver and bone is  from
material in the lungs and  lymph nodes that  has  been transported  via
the blood to the bone and  liver."
     Phenomena of pinocytosis and macrophage  transport  are mentioned
in a.section on "The Physiological: Basis of Transuranic Element Dose
Estimates" in Annex IIIj Reference (1), but the  extent  of their
contribution to transport of nuclides in the  body  is not known.

     See J. A. Schallberger, M. W. Dewhirst and  J. L. Lebel  "Lymph
Transport of Soluble and Insoluble Plutonium" pp.  19-27 in Radiation
and the Lymphatic System, ERDA Symposium Series  37, 1976, for~
additional : information-.                               ..-..-•- •-.  •-,..-.
59.  Department of Energy

     "0.09%" should be "0.009%"  (p-14, line-22)

     Staff Response - 0.09% is a misprint; 0.009% was used in the
calculations.
                  .- )    '           '.-•,-,         "             -.     ...'., !-.

60.  Department of Energy                                       .,..

     Although discussed,  the concentration of  transuranics in gonads,
necessarily assumed by EPA for dose calculations, is nowhere stated.
(p-14, line-20 to p-15, line-8)
                                135

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                                  37
     Staff Response - It was assumed in Annex III that 0.0045% per
gram of the transuranic material in the blood is concentrated in
gonadal tissue for both females and males.  Since the concentration in
bone is 0.009%, the gonad dose rate is half that of bone tissue.
61.  Department of Defense

     The ICRP model uses 0.009%, not 0.09  (p-14, line-22)

     Staff Response - See response to comment 59.


62.  Department of Energy

     Because of differences in testes anatomy between mouse and man,
it seems unlikely that the same kind of non-uniform deposition
observed in the mouse would have any effect on the dose to
spermatogonial stem cells in man.  (See A. L. Brooks, J. H. Die! and
R. 0. McClellan, LF-56, 399-403 (1976)).  (p-15, lines 1-4)

     Staff Response - The question of anatomy of the testes is not of
prime interest in determining the dose to spermatogonia.  What is
important is the micro-distribution of plutonium and other transuranic
elements.  Distribution of plutonium differs between rat, mouse, and
hamster testes, as discussed in Annex 3.  Green, et al., Nature 225:77
(1975) stated that plutonium appears to be deposited in intertubular
spaces (^47%) and in peritubular tissue (^42%).  Data on man and other
species is needed to resolve the question.  The dosimetry of plutonium
in gonads is discussed in reply to comment t24 and also in "Selected
Topics: Transuranium Elements in the General Environment," Tech. Note
CSD 78-1, referenced in Annex III.


63.  Department of Energy

     Parenthetical statement is no longer correct.  A recent study in
rats concludes that "the concentration of alpha tracks over the mature
or developing follicles and corpora lutea was only 10% of the
concentration over corresponding areas of stroma".  (See D. M. Taylor,
Health Phys. 3.3:29-31 (1977)).  (p-15, lines 4-5)

     Staff Response - A more exact quote from Dr. Taylor is: "Only
very limited autoradiographic studies were carried out on ovarian
tissue and these suggested that the concentration of alpha tracks over
the mature or developing follicles and the corpora lutea was only
about 10% of the concentration over corresponding areas of stroma.
(D. M. Taylor, Health Physics _32:29-31 (1977)>.
                                136

-------
                                  38
     Data developed from high resolution autoradiography by N. D.
Priesti Int. J. Radiat. Biol., 31:59-78 (1977) shows the answer  is  far
from clear at this time.  Data of -Green, et-al., Int. J. Appl. Rad.
Isot.3 28:497-501 (1977) shows there is redistribution in  the ovary
with increasing time after exposure.  Obviously while some information
has been available, further data on distribution of transuranics  in
the ovary should be obtained.
64.  Department of Energy

     Use of a 30-year dose in considerations of genetic risk  is
justifiable only on a population average basis.  This Guidance is
supposed to protect the "critical segment" of  the population, which  in
this case might be the 70-year-old men  still producing children.
This,''again, points out the lack of definition of this "critical"
segment.  (p-15, lines 14-16)

     Staff Response - A critical receptor is not addressed  in these
risk estimates.  All risk estimates both genetic and somatic  are in
terms of the number of health effects per"100,000 persons exposed.
Consideration of a critical .segment of  the exposed population refers
to the dose calculation, not the risk calculation.  The critical
segment of the exposed population is defined in the guides; see also
response to comment 35.  In passing, it might  be noted that only about
3 in 1000: families with the head of the household over age  65 have
children under 3 years of age.  Thus, those.age 70 males are  not a
problem.  (Population Characteristics 1973,: Department of Commerce
Series P^-20, #258, 1973)
65.  Jefferson Health Department

     On page  fifteen the  report states  that  for  an  equilibrium
pulmonary dose rate of one millirad per year,  the dose  rates  to
genital tissue in  the first  30 years  of.life is  calculated  to. be 1.4
millirad.  Does  this estimation take  into  account the pattern of
microdeposition  of-plutonium in the testes which would  give a higher
value in millirem  than might be anticipated  from the actual amount  of
plutonium present  in the  testes?   (P-15)

     Staff Response - Yes, the gonadal  dose  calculated  for
transuranics  does  take into  consideration  the  nonuniform distribution
of  the isotope in  gonadal tissues.
 66.  Department  of Energy

     The  statement is  incorrect.  Many soluble compounds have been
 employed  in  studying absorption of  transuranics from the gut.  The
 most extensive studies  employed nitrates.   (p-16,  lines  14-17)

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                                  39
     Staff Response - The statement only compares laboratory prepared
plutonium oxides to plutonium oxides found in the environment.  It
does not address transuranics in general.    ,
67.  Department of Energy

     It is not clear why "conservative estimates...are required".
There are risks of erring in either direction.   (p-16, lines 17-19)

     Staff Response - The risk of over estimating  the dangers of
plutonium were considered in the development of  these guides.
68.  Department of Energy

     The choice of transfer coefficients is presented as an arbitrary
decision with inadequate justification for the exact numbers chosen.,
It is not clear that the usual conservatism "applicable to public
health problems" is justified by the very limited problem associated
with transuranics in the environment.  This does not seem to be a
public health problem in the usual sense: of the term.
(p-16, line-19 to p-17, line-2)

     Staff Response - The Agency's selection of gut transfer
coefficients was largely based on the.recommendation of
Battelle-Northwest Laboratory scientists having, as a group, the most
extensive experience in this field.  See section 6.          •
69.  Department of Energy

     Sentence is correct only if 239pu aiuj 240pu are excluded.
Absorption of these isotopes, assumed to be oxides, is increased
50-fold by biological binding, according to Table A 3-5; 10%
biologically incorporated would result in 590% increased absorption of
239PUj240Pu>  (p-18, lines 5-6)

     Staff Response - The dose caused by the biological incorporation
of 239pu or 24Gpu oxides is essentially the same as for 238pu
and 24-l^jj £n the same form.  While the comment is mathematically
correct it is logically inconsistent.  The EPA statement was based on
the most soluble transuranics becoming available for incorporation
into ten percent of the diet.  A similar chain of events would lead to
one percent incorporation for the less soluble oxides of 239pu anc]
240Pu.
                                 138

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                                 40

70.   Department of Energy

     Sentence implies that gonad deposition is important and that it
is a primary site of deposition, second only to liver and bone; this
is misleading.  (p-18, lines 7-10)

     Staff Response - In view of the relative importance of genetic
consequences, the long retention of transuranics in gonadal tissue,
and the possible micro deposition of transuranics adjacent to
sensitive cells, the Agency believes the dose to gonadal tissues
deserves careful consideration.


71.  Department of Energy

     It appears that calculations are made  assuming that the  source  is
continuously  renewed and a constant amount  taken in over the  70-year
period.  This  is  inappropriate  when soil is  the source, especially.for
the shorter-lived  transuranics.  (p-18,  lines 21-24)

     Staff Response - The Guidance document  stated on page 111-19  that
"the occurrence of  lifetime  ingestion Is remote".  However,  renewed
contamination is  not  the only way long  term exposures could  occur
since patterns for  ingestion are a function of  land use.  The Tables
are not the Guides.  When doses are expected to decrease  so  that  there
is a high probability that the  bone dose in the 70th  year would not
exceed 3 mrad, this  should be  considered in the implementation of  the
guidance.


72.  Jefferson County Health Department

     On page  sixteen the  report states  "plutonium oxide found in the
environment  has  been shown  to  be  much more soluble than the refractory
oxide  utilized in animal  experiments".   The report states (page 19)
 that  organ  dose  rates listed in Table A 3-6 were  calculated on the
basis  of  organ masses appropriate for a reference .man but not for
 children.   The report also  states that  there is some evidence from
 studies  of  newborn animals  of  a high .rate  of transfer of transuranium
 elements  across  the gilt wall to blood.   On page twenty-one the report
 notes  that  the transfer of  americium and curium across the gut wall is
 about 100 times  greater than for  other transuranium elements.  (p-16,
 line 19)

      Staff Response - Contrary to this comment, age-specific  dose
 calculations for ingestion based on organ masses for children were
 made and reported on .page 20 and Table A3-9 of Annex III for  the case
 of ingestion by infants, the limiting case.  As pointed out in Annex
 III, children's organs are changing mass rapidly, so that the
                                  139

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                                  41

incremental change in total dose or in dose rate at age 70 was less
than +10%.  This was not considered enough difference to justify
age-specific intake calculations.  Dose rates and radiation risks for
inhalation were calculated on an age-specific basis.

     The statement on page 21 Annex III was misread.  The statement is
"Transfer of americium and curium to milk is about 100 times greater
than other transuranium elements..." not that the transfer across the
gut wall is 100 times greater.
73.  Department of Energy

     The reference to Section 3.4.3 is inappropriate, since this
Section does not describe in specific detail how gonadal dose has been
calculated.  (p-19, lines 13-14)

     Staff Response - Agreed, only the rationale was described in
Section 3.4.3.  However, see reponse to comment 60.
74.  Department of Energy

     This statement should be referenced.  (p-19, lines 19-23)

     Staff Response - High gut transfer of transuranics in the newborn
is discussed in Reference (1), Annex III.  Also in Section 6, W. J.
Bair and R. C. Tompson, letter communication (1977).

     The basic references include ICRP Publication 19 (1972); W. J.
Bair, pp. 171-230 in WASH-1359, 1974; M. F. Sullivan and A. L. Crosby,
BNWL-1950 (1975) and BNWL-2000, pt. 1 (1976).  M. F. Sullivan,
PNL-2500, Pt. 1 (1978) provides futher data.


75.  Department of Energy

     Ref. 15 appears to be an error.  (p-20, line-7)

     Staff Response - Reference 15 is a misprint.  Reference 25 is
correct.


76.  Department of Energy

     This argument should be further developed, since the referenced
paper is not readily available.  How different were the doses, and was
the possible promoting effect of cigarette smoking controlled?
(p-22, lines 1-7)
                                 140

-------
                              --42   '  .....

     Staff Response - The material referenced is also discussed by R.
W. Cihak, et al., Cancer, 33:1580-1588 (1974)) under the same title.
A follow-on article on Smoking, Occupation and A-bomb Exposure
(T. Ishimaru, £t al^, Cancer, 36: 1723-1728 (1975) reports that a
Mantel-Haenzel analysis of four-fold tables indicates that the
reduction in (Chi) when adjusted for smoking"... is not large enough  to
suggest a confounding of smoking with radiation dose..."  The most
these authors could conclude was that the data they had did not by
itself provide any suggestion of non-additivity of the effect of
radiation and the effect of smoking, when those exposed at less than
1 rad and those exposed at 200+ rads, were compared.
77.  Department of Energy                                          :

     Reference 35 is another critical reference which  is  unpublished,
and Annex 4 does not describe the procedures employed  in  sufficient
detail to check the accuracy of  the Table A 3-10  and subsequent
similar tables,  (p-24,  lines 14-16)

     Staff Response - The  life table analysis  used by  the Agency  is  a
straightforward application of the risk assessment methodology
developed by  the NAS-BEIR  Committee to prepare their summary  tables  of
effects, see  particularly  Table  3.1, 3.3, and  3.4 in the  1972 NAS BEIR
Report.  The  EPA analysis  is based on a stationary population and risk
of particular rather than  all cancers.  A general description of  the
model was given in Annex IV of the Guidance document.
 78.  Department of Energy

     It  is  not clear what  is meant  by "averaging the  geometric
 means",   (p-25, lines  3-5)

     Staff  Response -  Adding the  geometric means -and  dividing by two.
 79.  Department  of  Energy

     While  it  is impossible to  check the calculation because of
 unpublished critical  references,  it should be noted that the lung
 cancer  risk listed  here  is  about  5  times higher than either the
 Medical Research Council's  (England) estimate, or the estimate of ICRP
 Publication 26.   (p^25,  lines  14-15)

     Staff  Response - The MRC  adopted the 1972 BEIR Committee's lowest
 risk coefficient, 1 case per 10^  person years at risk per rem and 25
 years  at risk  for occupational  exposure.  The "EPA analysis is not
                                   141

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                                  43

 based  on occupational exposure and  necessarily considered a longer
 period of risk,  i.e., lifetime risk.   Moreover,  EPA utilized BEIR
 estimates of the risks due to  exposure during childhood,  a factor not
 considered by the MRC.  The Agency  has also included estimates based
 on  the relative  risk of radiogenic  cancer.   The  ICRP gave no
 information on how  they derived the risk estimates  published in ICRP
 #26.   Since they were considering occupational exposure,  their
 analysis may have had much in  common  with that of the MRC.


 80.  Department  of  Energy

     "140 bone cancers per 106 rad  "   (p-26,  line-16)

     S|aff Response - Agreed.   There  was a  misprint.  140 bone cancers
 per 10^  rad is correct.
81.  Department of Energy

     Marshall's statement  should be referenced.   (p-26,  line-23)

     Staff Response - The  appropriate reference for Marshall ejt al.:
J. H. Marshall, P. G. Groer and R. A. Schlenker "Dose  to Endosteal
Cells and Relative Distribution Factors for Radium-224 and
Plutonium-239 Compared to  Radium-226", presented  at the  1976 Alta
Symposium, Health Physics, in press.


82.  Department of Energy

     The bone cancer risk  employed is considerably lower than the
estimate one would derive  from the BEIR Report.   Should this not be
acknowledged?  (p-28, lines 13-15)

     Staff Response - The  EPA bone cancer risk estimates are somewhat
larger than those prepared by the 1972 BEIR Committee on the basis of
earlier data.  The estimates of bone cancer are risk based on human
exposures due to 244fta-  The BEIR absolute risk estimate for 224Ra
is 9.6 sarcomas per 106 skeletal rad per year at  risk, (page 128 of
the 1972 BEIR Report).  However, as the BEIR Committee pointed out on
page 127 of their Report,  long-term exposure to 2^Ra increases the
incidence per rad by a factor of about two.  Since transuranics
incorporated into bone yield chronic not acute exposures, the EPA
estimate is based on prolonged exposure, i.e, 25 per 10^ skeletal
rad per year at risk, (page 28 of Annex III).

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                                  44
83.  Department of Energy
     Dose values shown in Table A 3-11 apparently assume continuous
input over 70 years; if so, this is inappropriate, particularly for
soil contamination by the shorter-lived transuranics.
(p-29, lines 8-10)                                    '

     Staff Response - See response to comment 57.
84.  Department of Energy

     The reason given for not considering "relative risk" for bone
cancer is not clear,  (p-29, lines 11-16)

     Staff Response - The human data for the persons treated with
      indicates a finite plateau period; in such case, use of an
absolute risk model is warranted.  By definition a relative risk model
assumes that the time pattern for the occurrence of radiogenic cancers
is the same as that for the "naturally" occurring cancer.
85.  Department of Energy

     Bone cancer risks of Table A 3-12 apparently assume continuous
input over 70 years, which again would be inappropriate, particularly
for soil contamination by the shorter-lived transuranics.
(p-29, lines 22-23)

     Staff Response - See response to comment 57.
86 .  Department of Energy

     Sentence is not clear.  (p-29, line-23 to p-30, line-2)

     Staff Response - The sentence is poor.  The point to be made is
that even though the risks from 3 mrad alpha dose to the bone in the
70th year, following continuous ingestion of 239pu or 241^ are
similar, (see Table A 3-12) the dose per unit of activity ingested is
10 times higher for ^Am than for 239pu (see Table A 3-7).
Therefore, the maximum amount ! of 241^ that could be ingested under
the Guidance would be 10 times less than the amount of 239pu that
could be ingested.
87.  Department of Energy

     Statement is misleading.  The magnitude of the potential risk was
                                   143

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                                  45

inferred from animal data long ago.  It has received support, more
recently, from Thorotrast patients.  (p-30, lines 15-17)

     Staff Response - The possibility of liver cancer associated with
actinides but not the magnitude of  risk was shown by animal
experiments.  The Agency prefers  to use human experiences as a basis
for risk estimates and support this with animal data where necessary.
88.  Department of Energy

     Statement regarding the abundance of animal data should be
referenced.  (p-31, lines 21-25)

     Staff Response - References to animal data on liver cancer
induced by plutonium should include: L. A. Buldakov, et al., Problems
in Plutonium Toxicology LF-tr-41, 1970; G. N. Taylor £t al., pp.
105-127 in Radiobiology of Plutonium, 1972; G. N. Taylor, e± al.,
pp. 523-536 in The Health Effects of Plutonium and Radium,  1976.
89.  Department of Energy

     Reference 15 appears to be an error.   (p-32, line 21)

     Staff Response - Reference 15 is an error.  Reference 6 should be
indicated.


90.  Department of Defense

     Reference (15) discusses gonadal tissue, not liver.
(p-32, line-21)

     Staff Response - See response to comment 89.


91.  Department of Energy

     The concept of an equilibrium dose from a short-lived transuranic
is not consistent with a single-event contamination.
(p-33, lines 11-14)

     Staff Response - See response to comment 57.
92.  Department of Energy

     The ICRP factor of "20" should be referenced to ICRP Publication
#26.  It is a Quality Factor "intended for use only in radiation

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                                  46
protection and then for comparing actual levels of exposure with the
limits of dose equivalent...  These values.of Q are therefore not
necessarily representative of values of relative biological
effectiveness for other observed effects,  such, as stochastic effect in
animals at low levels of absorbed dose".   (emphasis added).  If the
number 20 is to be used as an RBE, not as  a Quality Factor, it should
be justified.  (p-34, line 7-10)

     Staff Response - Agreed.  Scientific  evidence supporting the
Agency's choice of RBE of 20 compared to x-rays was provided in the
Guidance document.  (Reference 45, Annex III).
93.  Department of Defense

     There is a loose association here between RBE and QF.  The ICRP
does not assign an RBE of 20 for alpha, it says the QF is 20 for.
radiation protection purposes.  (p-34, line-7)

     Staff Response - See response to comment 92.
94.  Department of Energy

     The origin of the factor "5" in "100  (5x20)" is not clear.
(p-35, line-1)

     Staff Response — The reduction in genetic effects due  to  low dose
rate low LET radiation in the 1972 BEIR Report is 3.4 for males  and
infinite for females.  Because  the Agency  is unconvinced that  low dose
rate, high LET particles will not affect the genetic competency  of
mature oocytes, the factor of 3.4 was arbitrally increased  by  50
percent to 5.
95.  Department of Energy

     This  sentence is misleading.  The "other  analyses^1  are  supported
by only a  single reference, and the "underestimate"  is relatively
insignificant compared with the overestimate alleged in  Ref. 49.
(p-35, lines 8-10)

     Staff Response - Although, as Ash,  et  al.  point out:  "The
question of whether multifactorial disorders should  be.considered  in
assessing  the risks of ionizing radiations  is  one  of semantics,  for if
multifactorial diseases  are maintained by mutations, they  are
essentially monogenic."  (Ash, et al., J. Med.  Genetics, 14:305-306
1977).  The Agency has treated multifactorial  genetic disorders  as
distinct entities.
                                    145

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                                  47

     References for the possible underestimate of multifactorial
disease in the 1972 HAS BEIR Report include: Development of Common
Indices for Radiation Health Effects, Final Report to EPA, A. D.
Little, Inc., 1974; Sources and Effects of Ionizing Radiation UNSCEAR
Report, 1977 and abridged versions of papers presented at an MRC forum
on hereditary disease in man, Journal of Medical Genetics, 14:305-331,
1977.
96.  Department of Energy

     Limiting gonadal dose to 30 years is a "population risk"
assumption that has questionable applicability  to a "critical segment"
analysis,  (p-36, lines 4-6)          '

     Staff Response - See response  to comment 64.
97.  Department of Energy

     This same caveat applies also  to  all other  calculations  of dose
from 244cm in this Guidance  and  should be discussed  in  connection
with these other calculations,   (p-36, lines  12-14)

     Staff Response - Agreed.
98.  Department of Energy

     Pertinent animal  data  on  leukemia  risk  from transuranics  is
ignored,   (p-37,  Section 3.9.1)

     Staff Response -  Pertinent  animal  data  on  leukemia from
transuranics was  not ignored.  It  is  summarized in Reference 51 by  Dr.
Vaughan.   However, the application of animal data on  radiation-related
leukemia  has been summarized by  UNSCEAR-1977 as follows,  "In view of
the  diversity of  these syndromes  myeloproliferative  and
lymphoproliterative diseases   and  in  the absence of any indication  as
to whether and to what extent  any  of  them might be akin to  human
leukemias, attempts to identify  the nature and  the number of cells  at
risk on  the basis of our present knowledge may  only be regarded as  an
'academic pursuit1."
 99.   Jefferson Country Health Department

      Leukemia due to bone marrow irradiation (page 37).   The report
 states  that  for a three millirad limiting dose to bone marrow,  the
 leukemia risk ranges from 0.4 to 1.6 cases per 100,000 exposed,  for
 the  absolute and relative risk models,  respectively.   This is

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                                ;  48

apparently based on the fact that the leukemia mortality due to excess
radiation is .about 1/5 of all radiation-induced cancers.  This
estimate is considerably less than my own and seems not to be a
conservative estimate (4).  (p-37)  :                              f

     Staff Response - No.  Effects from to1:al body irradiation were
estimated from the leukemia risk, not the other way around.  However,
the leukemia risk estimates in Annex III contain a computational
error.  Revised risk estimates for leukemia are presented in Section
6.1.                                                    .

     There is also a typographical error on page 37, Annex III, line
24.  The sentence "For a 3 mrad limiting dose to have,in the 70th
year,...",should read "For a 3 mrad limiting dose to bone in the 70th
year,..."
100. Department of Energy

     There is no basis given for the suggestion that "7% of  actinides
(are) distributed in the body tissue after inhalation;" such a
statement should be referenced.  The argument of  the paragraph  seems
specious, since a total body transuranic dose has.no meaning, and  the
"early deaths due to leukemia indicated in Table  A 3-17" were not
based upon total body plutonium.  (p-38, lines 3-11),

     Staff Response - Further information on the  derivation  of  the
estimate of 7% of actinides distributed in soft tissues is given in
Reference (1) in Annex III.

     The basic rationale is that ICRP-19 estimates that 10%  of     '.,...
plutonium (or other actinide) transferred to blood is  deposited in
soft tissue and,excreta.  From Durbin's reports on plutonium
distribution in, man (P. W. Du,rbin, pp. 469-530. in Radiobiology  of
Plutonium, 1972; P. W. Durbin and N. .Jeung pp. 297-313 in The Health
Effects of Plutonium and Radium, 1976); the distribution of  injected,
plutonium in animal tissues other than skeleton and  liver, is about
15.5? and in excreta 6.1%, i.e., a ratio of, activity in soft tissue  to
that in excreta that is approximately 70% to 30%.  That 7% of blood
plutonium is in soft tissue is a reasonable estimate,  is supported by
Mclnroy's observation that in tissues of occupationally-exposed   ,
individuals, the total body burden is distributed as follows:
            Lung
            Skeleton
            Liver
            Trachepbronchial
             ,  Lymph Nodes
            Other Soft Tissue
                       28.2%  ±  22.6%
                       47.5%  ±  29.3%
                       18.1%  ±  15.3%

                       , 4.7%'_.+' ,   4.6%
                        7'.0%  ±   lo.9%
 (J. F. Mclnroy,
 Radium, 1976).
pp. 249-270 in The Health Effects of Plutonium and
                                    1.47

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                                   49
 101.  Department of Energy
      It is not stated how the "estimated range of between 3 and 30
 early deaths" is arrived at, but it presumably derives from the
 highest and lowest values of the four different BEIR models, in which
 case it is not a range of risk, but simply the range of different
 estimates, each of which have a very large (and basically
 unquantifiable) uncertainty.  The statement is misleading since it
 implies that at least three deaths will occur in the cohort of 100,000.
 (p-38,  lines 16-18)

      Staff Response - The Agency agrees with the first part of this
 comment.   The range indicated is simply the range of different
 estimates, each of which have a large uncertainty.

      The  Agency does not believe the statement concerning either the
 minimum or maximum risk to be misleading.   As a best judgment based on
 current knowledge,  the Agency does not believe that the uncertainty in
 risks can be substituted for a postulated  threshold so as to presume
 zero effects for finite doses.
 102. Department  of  Defense

     Footnote  is  not  tied  to  table,  no  reference for table which is
 true for many  of  the  tables in this  annex,   (p-49,  Table A 3-5)

     Staff Response - All  comments on  table are  largely correct  but
 editorial in nature.
103. Jefferson County Health Department

     On page thirty-eight  (summary of health  risks)  the  report
estimates that the  total somatic  and genetic  risks due to  inhalation
of  transuranium element aerosols  causing  an annual dose  to  the
pulmonary region of one millirad  per year (20 millirem per  year).  The
estimated cancer risk to one million people is 90 premature deaths,
with an estimated range of 30 to  300.  An annual dose to the pulmonary
region of one millirad per year is roughly equivalent to 20 millirem
per year to the lung, 960 millirem per year to tracheobronchial  lymph
nodes, 60 millirem  to bone, about 30 millirem to liver, 4 millirem to
kidney and one millirem to gonads.  In my opinion, this dosage would
result in about 110 excess deaths due to  leukemia and a total increase
in all neoplasms of perhaps 1 to  2% over  a period of seventy years.
The incidence of all genetic diseases could increase by 1%  and ill
health related to chromosome mutation by  about 7% for all succeeding
generations from this dosage level.
                                 148

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                                  50

     Staff Response - The commentor has errored in his interpretation
and use of the 1972 BEIR Report,  see response to comment 21 submitted
by the same commentor.       -~-'-f:       •••-  *     '
104. Department of Energy                                          ,

     "Genetic Risk" requires definition in terms of the kind(s) of
effects the numbers refer .to.  Without further definition they might
be interpreted, erroneously, as "premature deaths".
(p-62, Table A 3-18)
     Staff Response - The genetic risk estimates referred  to  are  those
characterized as "Serious Disabilities" pages 55 and 56 of the  1972
BEIR Report.  These include: dominant diseases, e^g., Cowden's  disease
or Von Recklinghausen's disease; congenital abnormalities, and  such
constitutional and degenerative diseases as anemia, diabetes,
schizophrenia and epilepsy, but not heart disease, cancer,,or ulcers.
105. Department of Energy

     The "range" column is misleading.  It should.be  clearly  indicated
that these are not ranges in the, usual sense of upper and  lower
limits, or the result of some statistical measurement, but are simply
the highest and lowest of the numbers derived from different  models.
(p-62)

     Staff Response - See reply  to comment 101.
106. National Council on Radiation Protection and Measurement

     The dose rate calculations are performed assuming a  constant
infake over alifetime.  This may apply  to the effluent from a
processing plant and to ?39pu £n soils but not for  the other
nuclides in soils because of their relatively short half-liv£s.

     We recommend the inclusion.of tables for the nuclides  that  take
into account the decrease in soil concentration with  time due to
radioactive decay.

     Staff Response - See response to comment 57.  Changes  inactivity
level must be considered on a site-specific basis since radioactive'
decay is only one factor.  Transport of  contaminating material into or
out of the local biosphere may be more important.

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                                   51
 107. Ilene Youngheim
      I do not understand your terms Relative and Absolute  in regard  to
 risk, such as Table A 3-10.  I can understand the absolute premature
 deaths being less than the relative premature deaths, but why would  r
 the average years of life lost to premature deaths be less (for      ;
 relative risk), 18.4, than for absolute risk, 22.0.

      Staff Response - Relative and Absolute refer .to the form of the
 assumption underlying the projected numbers, of expected cancer
 deaths.  The question addresses the measures of the lifetime health
 risk due to lung cancer mortality induced by pulmonary doses.

      The absolute -risk estimates assume that the incremental lung
 cancer mortality resulting from exposure to transuranium elements
 increases in direct proportion to the dose, and is independent of the
 natural incidence of lung cancer.  The relative risk estimates assume
 that incremental increases are related to both the level of exposure
 and to the natural incidence rate for lung cancer in the U.S.
 population (i.e.,  risk is proportional to the product of the exposure
 level and the natural lung cancer mortality rate).  The use of
 relative risk models implies that radiation interacts with other
 factors that contribute to the natural incidence of cancer.

      The differences in the  average years of life lost to premature
 deaths assuming relative  and absolute risk is  a result ,of difference
 in  the age distributions  of  the  projected lung  cancer deaths.   U.S.   •
 mortality statistics show that lung cancer is  a cancer of old age,,
 hence fewer  years  of life lost per cancer death jare  predicted in
 relative risk calculations.     ;''...

 108.  Ilene Youngheim ..         ,
                             t     '          '•  -             j    ..-•-,,
     Annex 3,  3.1.   It  is  possible that  your estimation  of  effects  on
 gonads  has been  underestimated.   Plutonium has  concentrated in  the
 gonads  of animals  pasturing  close to  the Rocky Flats  Plant.

     Staff Response  - The Agency  staff believes that  its  evaluation,of
 genetic  effects  in humans resulting from plutonium inhalation or
 ingestion accurately reflects  the  viewpoints of experts  in  this
 field.  The presence of plutonium in  the  gonads of cattle grazing on
 contaminated  soils is expected, but is not  necessarily comparable to
 uptake and distribution by humans.


 109. Jefferson County Health Department

     The  report  states (page 34) "for reasons given below, genetic
damage from alpha particles is expected  to be about a factor of 100
greater than that assumed in the BEIR Report.  Based on current
                                  150

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                             '••••^ -52 .    ' •'   	•  ^ '

recommendations of the ICRP, alpha particles are 20 times more
damaging than x-irradiation for a number of biological endpoints,
including genetic effects.  This is not necessarily over^-conservative,
since an increase of about 20 compared to-x-irradiation has been
reported for genetic damage from highly ionizing neutron
irradiation."  In additiony there is some opinion  that the 1972 BEIR
Report may have underestimated the amount of multifactorial diseases
having a genetic component.  However, despite these conservative
assumptions on page 30, the report estimates that  a 30 year dose of
one millirad from alpha-emitting transuranium elements, in genital
tissue may cause only between 0.1 and two genetic  defects per  100,000
live births in the first  generation, with a potential in later
generations of 0.6 - 15 -defects per 100,000 live births.  This  figure
seems to be inconsistent  with estimates of risk to health posed by
four .millirem of iradionuclides in the support document for the EPA
Water Quality Regulations.                  •

     Staff Response - The basis  for the genetic risk  estimates is
given in Annex III of "Proposed  Guidance on Dose Limits  for Persons
Exposed to Transuranium Elements in the General Environment."   Similar
estimates for genetic risk  were  presented in  the support document  for
the EPA Drinking Water Regulations, EPA-570/9-76-003.


110. Jefferson County Health Department                   ;,

     On page  twenty  two  the report  cites  a1 1976 National Academy of1
Sciences Report which  states that  the  absolute  risk (the number_of
cases  that will  result  from exposure  of  a given population)  estimate
for bronchialfcancer  in  uranium miners  is  20  cases per million
organ-rad  per  year  at  risk, and not  10  as  indicated in the 1972 BEIR
Report.  The number  of  lung cancers  from alpha  radiation at a given
dose  appears  to  be  increasing as the  years  at risk in relevant
epidemiological  studies  are extended.   The relative risk estimate (the
ratio of  the  risk in those1 exposed to the' risk to  those not exposed)
in the 1972  BEIR Report  also is likely to be low.   "Assuming that the
relative  risk for U.S. miners is increased an a manner 'similar to the
absolute  risk,  it would  be comparable to the 1972 BEIR estimate for
Canadian  miners  who  have been similarly'exposed."  That is a 6%
increase  in annual  incidence per rad.  The 1972 BEIR Report assumes ia
 15-year latent peribd (10-20 years)  for all solid tumors induced in
both children and adults.                                  '

      Staff Response - The staff agrees.
                                    151

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  3.4  Annex IV - Risk Perspective

  1-    Department of Energy

       A more specific reference would be helpful.  (p-1, iines 8-9)

       Staff Response - The reference is to the brief description of the
  general characteristics  of the life table methodology.   A more
                                         methodol°8y " available.   (See
 2.   Department of Energy

      "Cohort" should be defined.   (p-1,  line  14)

      .S*;fff,?ersP?nse ~ A cohort  is  a group of  individuals of  common
 age. _Tne lifetime mortality experiences of cohorts of  100 000
 individuals are used in this analysis.

 3«   Department of Defense

      This section indicates that EPA has developed its own
 methodology, which is unavailable, but which may be changed.  This
 precludes any reasonable attempt to evaluate its validity and in
 effect,  is an unacceptable situation.   (p-1, Section 2)

      Staff Response   - EPA did not intend that the discussion of the
      5!     frV?1 methodol°8y would  give the reader the impression
 tne  liS  ?eM      f ,Tld *S  Changed  in the future'   A Ascription of
 *nH  M ?  «   * met*odol°8y "  available.   See J.R.Cook,  B.M.  Hunger,
 and  M.K   Barrick,  "A  Computer  Code for Cohort  Analysis of Increased
 Risks of  Death", EPA  520/4-78-012,  USEPA, Washington,  D?C.  (1978)

 4.   Department of Energy
referred *? "^ ^Z™ **? ' °* Wh°Se'  "method°l°8ical  differences"  are
referred to, or why.  The sentence  is confusing.   (p-2,  lines  14-16)
     Staff Response - There is a difference in methodology between
removing a risk from the life table and adding a risk  to it.
5.   Department of Energy

                    Methodol<)8y referenced, as TO11 as the methodolouy
                                            in order t
     Staff Response - See response to Comment 3.

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6.   Jefferson County Health Department

     The purpose of this annex is to make  the excess  death  rates  due
to exposure to radiation appear more acceptable by  comparing^them with
death rates from diseases and accidents presently experienced  by  the
U S  population.  The effects of radiation are further  compared  to
effects from background radiation received by the U.S.  population
about 100 millirem  to the whole body.  The implication  given is  that
if a person is receiving radiation  of  the  same order  or less than the
background radiation he is  already  receiving, that  the  additional
increment is not really significant.   This is not really the case,
since it is felt that background radiation itself produces  an ettect
on the  population in terms  of  an increased rate  of  cancer and genetic
defects.  Adverse effects  should not be  considered  more acceptable
merely  because  there are other  adverse effects  to which we  are exposed.
(p-4, Section 3)

      Staff Response -  The  purpose  of  this  Annex is  to provide
information  relevant  to an evaluation  by the reader of the
acceptability  of the  limiting risk for the guidance recommendations.
It  clearly  does not make  the judgment  of what constitutes an
acceptable  risk level,  nor does it argue  that an additional increment
of  risk is  not  significant.

 7.    Department of Energy

      Since there is no table identified as Table A 4-1  in  this Annex,
 presumably Table IV-1 is intended.  (Similar comment applies  to  page  .
 IV-5,  lines 4 and 10, and page IV-7,-  lines 10 and  14.)   (P-4, line 23)

      Department of Defense

      Table designation does not conform to that of the table  (A 4-1  vs
 IV-1).  Same applies to other  tables.   (p-4, line  23)

      Staff Response - All  references  to tables  in  Annex IV should have
 been designated with the  prefix IV instead of 4.

 8.   Department of Energy

      Cautionary statements concerning the limitations  of BEIR risk
  estimates are  needed  and  should appear  at this  point.
  (p-4,  lines 24-25)

      Staff  Response -  The BEIR report is  well  known and accepted in
  the radiation  protection  field.   We  do not believe that cautionary
  statements  concerning the limitations of the ,BEIR risk estimates are
  warranted.

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 9.   Ilene Younghein

      Annex 4, p.6 "Exposure to 1 mrad per year is therefore estimated
 to have a much smaller lifetime impact than does background
 radiation."  I should hope so!  If death rates, life shortening, and
 gentic^damage become as prevalent from plutonium as from background
 radiation, we would really be in sad shape.  There is one vital
 difference though.  We are stuck with background radiation, it is a
 risk we can do almost nothing about.  The risk from plutonium is a
 risk that we have added on to the risk from background.  It probably
 is erroneous to talk of life shortening and premature deaths in terms
 of background radiation.   They are part of the basic formula at
 birth.   Better to talk of life lengthening if we could devise a way of
 doing without it.  (p-6)

      Staff Response - We  agree.   The purpose of the guidance is to
 minimize the risk to persons in the general population from exposure
 to a single potential radiation source.   The recommended risk is well
 below that from background radiation.  Numerical  values are given to
 provide a perspective.

 10.   Department of Defense

      It is  not  surprising  that  the  life  shortening  is  approximately
 the  same  for both forms of risk because  the  calculational method
 employed  was the  same.  The  point  is  missed  by  this  reader,   (p-7
 line 7)

      Department of Energy

      That "the  life  shortening is approximately the  same for both
 forms of  risk" would be expected because  it  was calculated  the same
way  for both,   (p-7,  lines 7-8)

     Staff Response - The  comment is  incorrect.  The life table method
 takes into account the age distribution at time of death.  Since the
dose to various organs from inhaled and ingested transuranium elements
 is highly time dependent,  it can be expected that the age distribution
at death, for organ specific causes of death, will differ for each
organ.  Therefore, predicted life shortening for different types of
exposure (background radiation, inhalation and ingested transuranium
elements) is not expected  to be the same for all cases analyzed by the
life table method.

11.  Department of Energy

     The relevance of this  material is not established.
(p-7, section 4)
                                154

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     Staff Response - Section 4 addresses the comparison of other
forms of risks of death generally experienced by members of the
population to the risk from exposure to transuranium elements.
                                      f r*
                                      55

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  3.5 Annex V - Guidance Implementation
  1•    Department of Defense

  ^     mile the  Agency may believe "that these recommendations can be
  implemented...without requiring...unreasonable,  unnecessary,  and
  expensive  regulatory actions," the analyses  required to show  that this
  is  true  have  not  been done.   Such a statement should be referenced tou
  a study  or studies  showing this  to be  a fact.  (p-2, lines  1-3)

       Department of  Energy

       There  is a great  disparity between the  EPA's  belief  that  the
  recommendations can  be  implemented  without requiring unreasonable
 unnecessary and expensive  regulatory actions  and the actual case  of
  implementing.  Certainly  the  supporting material has  not  presented a
 convincing case that  implementation would not  be expensive.  This  is a
 prime example of  taking liberties between fact and supposition
 (p-2, lines 2)                                                 '

      Nuclear Regulatory Commission

      The conclusion that the proposed guidance would be capable of
 implementation at reasonable cost to licensees is not adequately
 supported by the information provided in the EPA Technical Summary
 Document.  Further,  the statement in the Federal Register Notice that
 the  Guidance is  capable of implementation at reasonable cost is in
 conflict  with  the  earlier  statement, in Rationale for Guidance, that
 EPA  has  found  that costs of remedial actions  will differ so greatly
 between  contaminated sites that generic cost-benefit  .guidance  cannot
 be provided.   More discussion should be presented to  support the
 conclusion  that  the  cost of implementing the  guidance at the reference
 level  of  soil  contamination is, in a generic  sense, reasonable.

     Staff  Response  - The  agency  staff  has evaluated  the status  for
 all  existing sites of known transuranium element  contamination  in the
 United States, and has  concluded that it is very  unlikely  that
 large-scale remedial  actions  will  be required  to  ensure  compliance
 with the  guidance  recommendations.   Therefore,  regardless  of the'cost
 of remedial actions  per  unit  area,  the  total  cost of  implementation
 for existing sites is  judged  to be  reasonable  and achievable.   In view
 of the above, and  the  alternatives  available  to the implementing
 agency, the agency staff staff  believes  that  the  statement is fully
valid.                                                            J

 ^    Costs of remedial actions  for sites which may become  contaminated
in the future are considered in Sections 4 and 5.
                                156

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2.   Department of Energy

  *   In the area of administrative implementation, there is a lack,of
unambiguous definition of the choices permitted, and the circumstances
under which they are permitted.  Three general procedures for
implementing the Guidance are set forth on p. 2 of Annex V, but one of
these is identified as the "preferred method," which could make it
administratively very difficult to choose any other.  Actually, there
can be no predetermined preferred method, since the preference will
depend upon the site-specific information obtainable and cost-benefit
considerations.
     Method "a" may not be the "preferred" method.  Preference  is
determined by the information obtainable and cost-benefit
considerations.. To label one method as "preferred" will make  it
administratively very difficult  to employ any  other method.
(p-2, line 10).

     Staff Response - The intent  of  the Agency is  to maintain
flexibility in  implementation of  the Guidance. Methods which
introduce the.cost ambiguity are  generally  to  be preferred,  consistent
with the site-specific  information available,  necessary  time
constraints, and other  similar factors.  The agency  staff  staff
believes that public acceptance  of any administrative  decision is
largely determined by a full and  complete disclosure of  all
information and that, on a technical basis,  any of the proposed
methods provides an acceptable implementation  procedure.

3.   Department of Energy
      Where  flexibility is  not permitted,  requirements should be
 precisely  stated;  where flexibility is permitted,  advice must be
 carefully worded  to avoid  compromising the intended flexibility.
 proposed Guidance  is notably deficient in this critical area.
The
      EPA should either leave this choice entirely to the agencies
 having regulatory and administrative responsibilities for the site in
 question, or specify which of these clearly defined procedures should
 be employed for each of several categories of clearly defined
 incidents; this would reduce the flexibility but simplify the
 administration.

      For example, soil sampling to a depth of one centimeter is
 specified, though the sampling of any reasonably sized area to this
 depth is virtually impossible under field conditions; sampling and
 preparation of soil samples should employ "a method which does not
 cause the breaking up of soil aggregates," but it is. doubtful if such
 a method exists; and acceptable maximum chance of a wrong decision in
 evaluating soil contamination levels is suggested to be 5-10%,
                                    157

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  although there is no assurance that such precision is possible under
  any reasonable circumstances; air sampling programs should "ensure
  that air concentration levels are representative of actual exposure
  conditions,   but no such sampling procedures exist; all methods
  employed must "have the necessary sensitivity, accuracy, and precision
  for purposes of implementing this guidance," but the necessary
  sensitivity, accuracy and precision are nowhere defined.

       Staff Response - The agency  staff believes that some uniformity
  of  approach  is  essential for proper interpretation of the results.     :
  For that reason,  generalized sampling  and analysis procedures are
  suggested which can be  expected to give results appropriate  for use in
  the decision making process.   Such generalized procedures obviously
  must  be  adapted to  local conditions, and it  is the responsibility of
  the responsible Federal  agency to choose procedures which will  best
  satisfy  the  implementation criteria of the Guidance   It is
  acknowledged  that precise adherence to the suggested  procedures may be
  impracticable or even impossible,  but  these procedures  should at  least
  form  the  basis  of a  program of evaluation and  major deviations  should
 be  justified.

      The  staff does not  agree  that sampling to  a depth of about one
 centimeter is impossible for most  types of terrain, and  believes  that
 soil preparation methods do exist  which do not  greatly change the
 physical characteristics of aggregates.  Statistical sampling
 techniques are generally designed  with a defined objective of accuracy
 and  precision, and the frequency of sampling is determined
 accordingly.   The time and resources required to achieve a 90-95%
 confidence level may sometimes be  unreasonable, but deviations from
 this objective should be justified.  The staff also believes  that air
 sampling programs currently in use at  several existing sites  meet the
 specified criteria,  and  do satisfactorily measure annual average
 ambient  air concentrations.   The "necessary sensitivity, accuracy, and
 precision of analysis techniques  represents  a judgment situation and
 is ultimately closely related to the overall  confidence level  required.

 4.    Department  of Energy

      If  these procedures  are  available  they should  be  referenced.  The
 available  procedures  are  largely concerned with the evaluation of
 population averages  and are not appropriate to  consideration of  the
 "critical  segment."   (p-5,  lines 2-6)

     Staff Response -  The statement refers specifically  only to
measurement, and not  to calculation! procedures.  Application of  the
guidance recommendations  to a "critical  segment  of  the population" may
require knowledge of site-specific population or land use
characteristics.

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5.   Department of Energy     .
                     1 •'-    ~ ' .  *- -_  :. ^*'     _    _-_. "'' ' "' - ' ,•' '  '
     It' is not clear what this sentence is trying to say, but the
several reasonable possibilities all seem to be incorrect.  It
provides little guidance unless "in close proximity  to" is given more
specific definition.  (p~8, lines 8-11)

     Staff Response - The intended, meaning .is that the particulate
content of air is mostly derived from surface materials located at .
some distance  from the point  of measurement,  and  only a small fraction
is that resuspended from the  immediately adjacent area.

6.   Department of Energy

     If there  is  a method "which does not cause the  breaking up of.
soil aggregates"  it should be referenced.   (p-12,  lines 9-11)

     Staff Response - The  intended meaning  is to  avoid, deliberate
breakup of aggregates by milling or  grinding in those  samples
designated for particle  size  analyses.

7.   Department of  Energy              ....••.            .

     A single reference  seems inadequate, for this entire  subject.,
(p-12  lines  13-20)

     Staff Response -   A more detailed discussion of Guidance
 implementation is provided in Section 5.

8.   Department  of Energy           .               -    ,   -

     The  statement that a 5-10% maximum chance of error is "generally
 considered  appropriate" leaves one uncertain,as to whether EPA .will
 consider  this an appropriate criterion.  If this is, in fact, the
 criterion,  it is a very important part of the Guidance and requires
 further discussion.  (p-14,  lines 12-14)

      Staff Response - The staff believes that  a 90-95% confidence
 level  generally represents a realistic objective for environmental
 measurements.  We do not think that further discussion is required.

 9.   Department of Energy

      For how  long is "stabilization" considered  effective?
  (p-16, lines  7-12)

       Staff Response - Stabilization  is a temporary  measure, designed,
  to prevent dispersion during the initial phase after  deposition when
  the material  is  most mobile.
                                    159

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 10.  Department of Energy

      It seems inappropriate that an Annex on implementation includes
 only four references, two of which are not referred to in the text.

      Staff Response - The comment seems to misinterpret the intent of
 this Annex.  The staff believes that the implementing Federal agency
 has primary responsibility for evaluating the situation and for
 choosing the appropriate remedial actions.  The principal purpose of
 this Annex is not to provide a technical implementation manual, but
 rather to give sufficient information to members of the general public
 to let them judge the feasibility (and problems) of implementation.

 11.  Department of Defense

      "Much greater or much smaller" has no precise meaning and is
 therefore useless,   (p-3, line 19)

      Staff Response - The terms are relative and interpretation is at
 the discretion of the implementing  agency.

 12.   Department  of Defense

      Reference the  procedures  and  indicate  their acceptability for use
 in compliance,   (p-5,  line 2)

      Staff Response  - See response  to  comment  10.

 13.   Department  of Defense

      This  entire Annex is so vague  and  contradictory  that  it is
 essentially useless.   It  can only result in  controversy, confusion and
 possible  litigation.   Several  examples  illustrate  this:

      (a)   Page 14,  line 21:  In effect, it says  you can choose a
 statistical method to  give  the  results  desired.

      (b)   Page 11:  Says  ingest ion of dirt may need consideration
 because of importance, but  in Annex II, this route is considered of no
 importance.

     Staff Response - The  staff does not agree that Annex V is vague
 and contradictory, and believes that it serves its intended purpose
 (a) The paragraph referred to says that, where acceptability of an
 area  is in doubt, decisions are best based on statistical tests, (b)
The sentence in entirety  reads  "the more unusual transfer methods  to
people .... may need to be examined if shown to be of importance."
                                   160

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14.   Jefferson County Health Department

   :  On page 5, emphasis is placed on the annual average transuranium
element concentration in air.  However, air sampling devices may not
provide an accurate estimation of the potential risk to residents of
areas contaminated .with plutonium,

     Staff Response - The staff believes that the annual average
concentration of transuranium elements in air is the best indicator of
the inhalation hazard to persons  from chronic exposure.  The accuracy
of measurements will need to be evaluated for each  specific occurrence.

15.  Jefferson County Health Department

     In the last paragraph on page 9, the Agency again  appears  to
support the use of resuspension factors, which were reported earlier
to have a variability of as much  as  one million.  The use of such a
factor, it  seems to me, is very questionable.

     The guidelines recommend that soil samples should  be taken to  a
depth  of one  centimeter and  the transuranium  element activity measured
in the particles less than  two millimeters  in size.  This^sample, as  I
have pointed  out previously,  is inappropriate for evaluation of a
respirable  dust hazard.   In  addition,  I do  not  feel, as the Agency
does,  that  samples may  be  composited for  a  single measurement.   If
this is done,  hot  spots will  be undetected  when  averaged with many
other  locations with  lower  levels of activity.   I  find  these
guidelines  to be unacceptable.  The  best  way  to  evaluate a  hazard  from
airborne  contaminated dust  is by  use of respirable  dust sample  from
the  surface of the soil.

     Staff  Response  -  (a)  The staff  does  not  specifically support  use
of a resuspension  factor,  and recommends  that the  relationship  between
soil and  air  concentration be determined  by use of  the  mass-loading
calculational method,  (b)  The staff  does  not  support the use of Dr.
Johnson's  "respirable dust" sampling method and believes it to  be
inappropriate for.implementation  of  this  Guidance   (see Section 7).
 (c)  Compositing  of several samples  for  chemical analysis is a .
generally used and accepted technique.  "Hot  spots" are of^importance
only to  the extent that they change  the  uptake by   an individual.

 16.   Jefferson County Health Department

      On page 12,  the report mentions "the usual method for determining
 distribution of soil particle sizes  is by sedimentation analysis" and
 then cautions that "soil characteristics should be  altered as  little
 as possible in the collection and preparation of the soil  sample, and
 care should be taken to choose a method which does  not cause the
 breaking up of soil aggregates that were present when  the  sample was

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taken."  This  statement  appears  very  strange  when  we  consider  that  the
alternate method used  by the  EPA,  Rocky  Flats and  the Colorado State
Health Department  involves  the use of agricultural soil  samples which
are dried and  pulverized to a fine powder  in  a steel  ball  mill.

     Staff Response -  The comment  apparently  confuses two  entirely
different aspects  of the evaluation,  namely size distribution  of
particles and  chemical analysis  of the soil samples.   Retention of
soil physical  characteristics is essential only for.the  determination
of the particle size distribution,  while reduction to a  fine power  is
a preliminary  step in  the chemical analysis procedure.

17.   Department of Energy

     It has not been shown  that  "most of the  potential hazard  is
derived from contamination  at, or  near,  the surface." This depends
upon the depths of the disturbances possible  in the area.  The
contention that "most man-made disturbance will reduce the
concentration  in the top layer" may not  be true if levels  higher than
those permitted by the Guidance have  been reduced  by  mixing through
the top layers.  In such a  case, further disturbance  will  gain nothing.
(p-4)
     *
     Staff Response - We agree with this comment but  would point out
that the conclusion is applicable  only to the  choice  of  remedial
actions and does not change the rationale for  the  Guidance.

18.   Department of Energy

     A major ambiguity surrounds the  administrative aspects of
determining and certifying  compliance with the  Guidance.   It is
implied that reports must be  made,  but never  stated to whom.   It is
recommended that remedial action be taken quickly, but requirements
for environmental  impact assessment,  evaluation of area  contaminated
to a precision, of  5-10%, sampling  of  air at weekly intervals,  sampling
food, etc., will,preclude quick action.

     Department of Energy

     To whom do the Federal agencies  "certify  that Guidance
values«..are not being exceeded?"  At what level above background is
such certifipation required?  In other words, what triggers this
procedure?  (p-4,   lines  11-14)

     This paragraph discusses vaguely defined requirements, with no
indication of which entity will be  responsible  for those    ,       '
requirements.  A definition of reports required, and  to  whom they
should go, is not  discussed in this Guidance,   (p-11,  lines 7-13)
                                   162

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     Department .of Defense

     To whom do the Federal agencies certify that 'guidance values  are
not being exceeded?  What is the process, time requirements,
administrative procedures, etc.?  It is not made clear here or
elsewhere.  (p-4)          ,                      	

     Staff Response - No reporting requirements  for  this  Guidance
exist at present, but the Agency may establish such -requirements at  a
future date.                         .                  	

     It is not  the intent of the Guidance to require  administrative
procedures that would preclude  prompt  remedial actions  in the  event  of
a contaminating event.                   . ,. .

19.  Department of Energy                ...

     This .sentence seems "to assume  that  there  is a particle  size
distribution  characteristics of a specific  site.  Actually this
distribution  will vary'with wind  speed,  soil moisture,  dust  brought
from off-site,  mechanical  disturbance, etc.  To  obtain any realistic
measure is a  very  long  and expensive procedure.   It is not clear that
such intensive  study, which can only be  performed at a few points,
would  be  cost-effective.   (p-5,"lines  12-13)                 -

     Staff Response  - We  agree 'that the sentence is ambiguous.  'It is
intended  that the  implementing agency use site-specific data to the
maximum extent  practicable, without going to  the extreme of a
long-term research  effort.                              .

20.  Department of Energy

     This sentence is  unrealistic.   Many current studies are
indicating the complexity of  environmental solubility considerations.
Predictions  in this area are  extremely uncertain.  In any case, the  -
 only guidance given in Annex III is for Class Y compounds.
 (p-5,  lines  15-20)

      Staff Response - We disagree with the conclusion that the
 sentence is  entirely unrealistic, at  least to the extent  that  the
 solubility class of most transuranium elements  in the environment can
 be inferred from their history or other data.   Hov/ever,  the comment is
 correct in that major uncertanties do exist and it  cannot a priori'  be
 assumed that Class Y (insoluble) is applicable  in all cases.   A
 discussion of the changes introduced  by Class W (soluble) compounds  is
 given in Section 6.             .    '         .    '          ;

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 21.  Department of Energy

      Sentence is more  intelligible  if  "into"  is  changed  to  "in."
 However, the relationship  implied in the  sentence  is not established.
 (p-7, lines 5-7)                                                      ^

      Staff Response -  The  reference is to the greater availability of
 transuranium elements  biologically  incorporated  into plants or animals
 (See Annex III)

 22.   Department of Energy                                            :

      Perhaps the most  serious ambiguity is that  surrounding use of the
 soil screening level.  Its use is appropriately  recommended in the
 Summary Report (p. 29) as a procedure that "can  serve to reduce the
 land area requiring evaluation and minimize the number of measurements
 needed."  In Annex II  (p. 25) it is stated that  the screening level
 "will identify land areas where no additional monitoring is
 required."  But in discussion of the soil screening level in Annex V
 (p. 9)  it is stated that "In all cases the cumulative doses to the
 critical segment of the population must be considered," which will
 require the complete characterization of the contaminated area that
 the soil screening level was designed to avoid.   Again,  in Annex VI
 (p. 11), it is  stated that in the off-site areas adjacent to the Rocky
 Flats plant,  "more intensive evaluation may be needed to determine the
 actual  dose rates  to the general population," this  despite  the fact
 that the soil  screening level is not exceeded (as indicated on p.
 10).  In Annex  V (p.  8) it is stated that "the screening level concept
 may not  be  applicable when the soils of a contaminated  area contain
 these^nuclides  (Am and Cm)  in amounts  greater than  20% of the  total
 activity."   The  potentially very useful concept  of  a soil screening
 level has thus been  compromised  by vague  references regarding  its
 inapplicability  under  various circumstances,  to  the .point that it  is
 doubtful whether  its  use  could ever  be  justified.

      It  is  suggested  in this  paragraph  that  a  conservative  "derived
 air concentration  limit"  be employed as a  test of compliance,  when
 other approaches are  "difficult  or impossible."   If a simple cheap
 comparison  to an air  "screening  level"  is  possible, why go  to  the
 expense  of unnecessary  site-specific evaluation.  This is the
 expressed philosophy  on which the soil  screening  level is based.   It
 would seem  that the "air  screening level"  should  be similarly
 considered and included along  with the  soil screening level  in the
 Summary  Report.  (p-15, line  21)

     This says that in  all  cases you must  do everything, which
 contradicts the philosophy  of  screening levels.   (p-9, line  9)

     It  is stated that  "the screening level concept may not be
applicable."  (p-8, lines 12-17)                    	
                                   164

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     Staff Response - The intent of the ''screening level" is as
stated, name1y to exc1ude from detailed evaluation those areas where
contamination is sufficiently low so that there is little possibility
that resultant doses to persons would exceed the guidance
recommendations.  This judgment is based on calculations which have
considered both the inhalation and ingestion pathways, but which may
not have included some very exceptional circumstances.- The presence
of "more than 20 percent of the total activity as americium or curium,
which are more soluble and therefore represent a greater ingestion •
hazard, is such an exception.  Therefore, the staff believes that the
admonition to consider such exceptions, where warranted, is both valid
and indicated.

     The air screening level provides assurance only  that Guidance
levels are not exceeded through the inhalation "pathway.  The use of
such an air screening level is not precluded by the Guidance
implementation procedures.

23.  Department of Energy                                    '

     The "derived air concentration limit" must be based on singularly
defined parameters.  The specified AMAD  is presumably 0.1 urn.  The
phrase "not to exceed" therefore  seems inappropriate.  While
conservatism is perhaps justified in the derivation of such a
"screening limit," the unrealistic AMAD  of 0.1 urn would  seem to be
excessively conservative.   (p-6,:lines 2-6)

     Staff Response - An AMAD of  0.1 micrometer may be used if
measured values are not made for  the specific  site under
consideration.  We do not believe this value  to be excessively
conservative because  the difference in dose  calculated using an AMAD
of  0.1, micrometers compared  to  the more  "realistic" value  of 0.5
micrometers  is  only a  factor of 2.

24.  Department of Energy

     "Disturbed  sites" are  not  addressed.  These  are  part  of  the
exposure potential and should not be overlooked.   (p-11,  lines  15-19)

     Staff Response - The  "disturbed  site" was addressed in .the
 derivation of  the  soil screening  level  (Annex II)

 25.  Nuclear  Regulatory  Commission

     The  alternative  remedial  action  of  establishing  restricted  access
 or  use of  the  area in question  is not  discussed in the federal
 Guidance.  We  propose that,  at  least  for future contaminating events,
 the guidance  state that  this  alternative not be used, if at all
 possible.
                                     165

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                                  11
      Staff  Response - Remedial action choices are the responsibility
of  the  implementing agency.   However, we agree that it is preferable
to  clean  up a  future contaminating event and that simply establishing
restricted  access  should  not  be used if at all possible.

26.   Nuclear Regulatory Commission

      We are concerned that  the proposed reference level of soil
contamination  which is presented in the statement of consideration as
a screening level,  "based on  limited data available for several
existing  sites," may be interpreted as an effective action level.
Discussion  of  the  reference level in the presentation of the modeling
methodology used in the backup document appears to be sufficient.

      Staff  Response - We  agree.that the screening level should not be
considered  an  effective action level.

27.   Nuclear Regulatory Commission

      In order  to clarify  that  the operative guidance for newly
contaminated areas  are the dose rates specified in paragraph one of
the text  of Proposed Guidance,  we recommend that the second sentence
of paragraph two be deleted.

      Staff  Response - We  disagree.   The intent of the second sentence
is  to make  it  clear that  not  only is the dose to be minimized but  that
remedial  actions are to continue until doses are projected to be well
below the guidance  levels.  It  is not likely to be possible to verify
compliance  within a time  frame  comparable with the time needed for the
remedial  action.  A degree of  conservatism is justified.

28.   National  Council  on  Radiation Protection and Measurements

     We recommend that the actions  following a future possible
accident be  better  defined and  that  a study be made to show that these
limits  are  appropriate.

     We recommend that this Annex be rewritten with careful
consideration  of the  practicality and cost of the requirements and,
that  a  specific section on implementation following accidents  be
included.

      Staff Response  -  Comments  on the proposed guidance  have  supplied
valuable additional  information  on  the potential  costs  and
effectiveness  of remedial actions for possible future contaminating
events.  These are  discussed in  Section 4 and 5 and the  Agency has
concluded that the  Guidance is  appropriate for future contaminating
events.

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                                   12
29.  Jefferson County Health Department,                • • *..     .'--'•

     This screening level value is not conservative, and does not
provide adequate protection to the public.  In my opinion, residents
of areas with this degree of contamination will be unwilling to accept
the effects of such exposure.

     Staff Response - We disagree.  In our opinion the screening level
is conservative.There is no evidence that residents of areas
contaminated to levels below the screening level will be unwilling to
accept the very small potential risks.

30.  Jefferson County Health Department

     The report notes that the choice of suitable methods for sampling
and analysis is the responsibility of the agency implementingthe
guidance.  In the case of the area around Rocky Flats, there may be
several such agencies involved in this implementation, i.e. j the
Health and Safety Laboratory of the Department of Energy, the State
Health Department, and the Jefferson County Health Department.  It
would be desirable for the agencies to agree on a standardized
approach.                                                 - .     .   s

     Staff Response - We agree.

31.  National Council on Radiation Protection and Measurement:

     The Implementatipn Annex provides a number of general statements
as to methods of assuring that the guidance is met.  A number of these
appear to differ from similar statements in other Annexes and the
general impression left is one of confusion as to what should be done
and how well.  There is no specific implementation for accidental
releases so that one can only conclude that the entire Annex will
apply-                      _                   .     ,.'-'-.-. ,x  ; •_

     We recommend that this Annex be rewritten with careful
consideration of the practicality and cost of the requirements and
that a specific section on implementation following accidents be
included;                                                         '   '

     Staff Response - Annex V is intended to provide generalized
guidance on methods appropriate for assuring compliance with
recommendations.  In the absence of more specific information on where
conflicting advice is given, no answer can be provided on this comment.

     Evaluation of the consequences of possible accidents, and of  the;
need for remedial actions, should follow the same general procedures'
as outlined in  this Annex.  However, time constraints on  initiating
actions are expected to be more stringent for instances of new
contamination.
                                   1C?

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                                    13
32.  Department  of Energy

     To avoid  lengthy  future  contention  over  what  this  Guidance  does,
or does not mean, it  is  recommended  that  the  entire  document be
carefully reviewed to  eliminate  Inconsistencies  and  ambiguities;  and
that Annex V be  rewritten  in  a clear  and  simple  fashion, being careful
to recommend only those  procedures whose  applicability  has  been
demonstrated,  and to  avoid  comment on procedures that are left to  the
discretion of  the Agency implementing the Guidance.

     Staff Response -  Refer to comment 31.

33.  Department  of Defense
     The intent and  impact of  this  sentence appears ambiguous, while
"unnecessary cost" may be avoided,  the
large.  (p-2,  lines  20-23)
"necessary" cost may be very
     This is a misleading oversimplification of  the proper objective
unless it is made clear that "cost" includes such  items as dislocation
of people, environmental damage and other non-monetary costs.  The
mention of non-monetary costs earlier in the paragraph is not adequate
to prevent this misinterpretation.  (p-15,  lines 17-20)

     The very important non-monetary costs  considered in these
paragraphs should not only be considered in deciding between
alternative cleanup procedures, but should  be balanced against the
risks of no remedial action at all.  (p-18, lines  13-21)

     These psychological costs, which receive only passing comment in
the last sentence of this Annex, must be considered to be a serious
risk involved in transuranic contamination of the  environment.  Many
of the actions that might be taken to reduce other risks may increase
the fear that leads to these psychological costs.  (p-18, lines 20-21)

     Staff Response - Economic considerations are  described in
Section 4.  Non-monetary and psychological costs are difficult to
quantify.

34.  Nuclear Regulatory Commission

     It appears that the costs of taking remedial  action for
facilities licensed by this Agency would substantially exceed the
lower limit value of $500 per acre assumed  for the proposed guidance.
For example, disposal of surface soils by burial in commercial
low-level waste burial sites would probably equal  or exceed the costs
of the general per cubic foot charge for burial.  Using a value of $3
per cubic foot (NUREG-0217) would result in an estimated cost of $5000
per acre for burial charges alone.
                                   168

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                                   14
     Some NRC licensed facilities are located in areas having other
buildings and structures which would be substantially more costly to
decontaminate than for a facility located in a remote area.  A recent
"Draft Engineering Evaluation of the Latty Avenue Site, Hazlewood,
Missouri," by Ford, Bacon, and Davis, Utah, Inc., dated January 1978,
indicates that the five remedial action alternatives evaluated for the
18,300 cubic yards of contaminated material at the 10 acre site, range
from $457,000 for cleanup and temporary storage of contaminated
materials on site to $4,131,000 for the alternative of disposal at a
commercial nuclear waste disposal site.  These estimates are
comparable to the data presented in Table VI-2 of the EPA Technical
Summary Document.

     Staff Response - We agree that the costs of remedial actions
would generally greatly exceed $500/acre (See Section 2.3, comments 7,
8 and 9).  The numerical estimates provided are very useful and give
an additional perspective applicable to decisions on implementation
options.

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                                    15
EDITORIAL COMMENTS - The following comments were accepted  but were
considered editorial in nature.

Department of Energy

Page V-6, lines 9-12

     The admonition to seek site-specific data  seems  to be
inconsistent with the qualification of the first sentence  of this
paragraph, which says the method is to be employed only when
site-specific data are "difficult or  impossible" to obtain.

Page V-7, lines 19-23

     "Under such conditions" requires definition.  On the  previous
page "characterization of the source  term" is considered necessary
only "when these levels approach that of the Guidance
recommendation."  Here the qualification is lost.

Page V-ll, lines 1-4

     This sentence seems to contradict the discussion on p. 17 of
Annex II where the significance of children eating dirt was dismissed
because it required "extreme assumptions."

Page V-12, Section 5.1.1

     No reference is provided.

Page V-14, lines 21-24

     This sentence would be improved by eliminating the last four
words.  As it stands, it seems to say you can prove whatever you want
with statistics.  Appropriate references should be provided.

Page V-15, lines 1-9

     This paragraph introduces for the first time, without definition,
terms such as "true fraction," "lower bound," and "upper bound."  This
leads to confusion, since the paragraph appears to acknowledge that
portions of land area may reasonably exceed the limiting soil
concentration.  Extensive rewording is suggested.

Page V-15, lines 15-17

     Not all transuranics have long half-lives.
                                      1 Hft
                                      JL £ l.«

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                                   16
Page V-16                              .                      ,     . '

     It is very easy to misinterpret this page as a listing of always
available alternatives among which one chooses on the basis of
site-specific costs.  It should be made clear that at many sites many
of these options would not be available.                             ;

Page V-17, lines 10-13

     This sentence is not clear.  It should be reworded or>deleted.

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3.6 Annex VI - Environmental Assessment

1.   Department of Defense

     It is not clear whether the reference to NEPA ,is  in  the context
that EPA has to file an EIS for the proposed Guidance  or  that  the
various agencies who will be involved  in clean-up have  to file an
EIS.  Clearly, for major Federal actions, an EIS is  required,  thus, it
is assumed any cleanup of any magnitude would require  such a
statement.  Which is the case being presented?  The  relationship is
not distinct.  Clearly, if an EIS has  to be filed before  any cleanup
is undertaken, the various requirements will cause delay  in acting.
What is done in the meantime—stabilization, evacuation of people,
etc.  This section serves to confuse rather than clarify,  (p-1)

     Staff Response - Implementation of the Guidance is the
responsibility of the agencies having  site jurisdiction or causing
environmental contamination.  In the event of future incidents, it is
assumed that proper and expeditious remedial actions appropriate to
the occasion will be taken.  For existing situations,  where time is
not a critical factor, the evaluation  of all impacts and  alternatives
should be considered and the preparation of an EIS might  well  be an
integral part of the decision making process.

2.   Department of Energy

     This paragraph would seem to require an Environmental Impact
Statement or Assessment before any cleanup action is taken.  Thus, in
compliance with Annex V, the area must be surveyed to  a precision of
5-10%, uptake in potential food crops  measured, air  samples taken at
weekly intervals, etc.  A dose assessment must then  be made and
alternatives considered, taking account of monetary, societal, and
environmental costs.  All of this could take from one  to  several
years.  Thus, if any land is contaminated by transuranics (presumably)
to any level and for any size area), the area must be  stabilized and
restricted until all this is done.  If the above description  is not
the impression intended, the paragraph should be rewritten to  clarify
the intent,  (p-1 .lines 20-26)

     Staff Response - The Guidance does not state the  requirements  for
an Environmental Impact Statement.  Such a requirement may be  dictated
by the magnitude of contemplated remedial actions, and appropriate
discisions in this regard must be made by responsible  State and
Federal officials.  It is intended that such decisions be governed  by
common sense and a concern for the health and safety of the
population,  rather than by a strictly  legal interpretation of  the
guidance  document.

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3.   Department of Energy

     At some point mention should be made of the possible
complications posed by an endangered species living in a contaminated
area,  (p-2)

     Staff Response - Such detailed evaluations must be considered on
a site-specific basis.

4.   Department of Energy

     "Temporary disruption of normal activities" is a very optimistic
way of describing the more realistic description of. the previous
comment,  (p-2, line 7)

     Staff Response - The magnitude of adverse impacts is a function
of the scale of remedial actions.  "Temporary disruption of normal
activities" is intended to apply to that range of anticipated remedial
actions which could be expected to occur for events with a higher
probability of occurrence.

5.   Department of Energy

     "Animals...and fauna" is redundant.  (p-2, line 9)

     Staff Response - We agree.

6.   Department of Energy

     The  fact that the detailed study of ecological impacts will not
be received until the end of  1977  implies that this Guidance was
formulated without knowledge  of such detailed impacts.
(p-2,  lines 17-20)

     Staff Response - True.   The Guidance was derived on the basis of
health impacts, not a detailed knowledge of  ecological impact for
remedial  actions.  Such knowledge would foe most useful for evaluating
alternatives of remedial actions, which  is beyond the scope of  the
Guidance.

7.   Jefferson County Health  Department

     If the guidance  from the International  Commission on Radiation
Protection  is to  be considered I think it is important to know  who is
on the commission, which industries  or agencies they  represent, and
whether the members have signed statements of disclosure concerning
financial and other interests which may  impinge on  their duties as
commission members.   (p-5)
                                    173

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      Staff Response - The recommendations of the International
 Commission on Radiation Protection have been rejected as inappropriate
 for this  Guidance.   Therefore,  the remainder of the comment is
 irrelevant.

 8.    Department of  Energy

      Whether these  values are "unacceptable" would depend upon the
 probability  of exposure from other sources.   If all sources of
 exposure  are very unlikely,  any one of them should be allocated a
 major fraction, if  not all,  of  the limit.  This seems to be a basic
 area  of disagreement between the philosophy of this Guidance, and what
 other respected bodies consider to be  a more reasonable philosophy.
 (p-5, lines  9-13)

      Staff Response - The rationale and limitations for the statement
 are given in the remainder of the paragraph.   The  Agency does not
 agree that higher dose rate  limits,  with or  without the principle of
 dose  allocation,  represent a "more reasonable philosophy."

 9.    Department of  Energy

      Does  the  Guidance permit this?  "Could  well be acceptable" is not
 sufficiently precise,   (p-5,  lines 13-15)

      Staff Response - The Guidance is  intended to  permit,  and even
 encourage, some judgment  on  the part of the  implementing agency.

 10.   Department of  Energy

      It would  be  helpful  if  the Colorado  standard  was  interpreted in
 terms of units  more directly related to the  EPA Guidance.
 (p-5, lines  21-23)

      Staff Response -  The  Colorado Guidance  is  stated  on a legally
 defined basis  and cannot  be  converted  to  other  units without
 introduction of certain assumptions.   The EPA guidance  is  not  stated
 in  terms of  a  soil  concentration level, and correlations must  be made
 on  a  site-specific  basis.

 11.  Jefferson  County  Health Department

     Reference  is again made to  the  present standard of  2  dmp/g of dry
 soil adopted by the  State  of Colorado  in  1973,  representing about  25
 times average plutonium fallout  background for  Colorado.
Unfortunately,  the  standard does  not define the meaning of  the word
"soil" which has been  taken to mean  agricultural soil.   I  agree that
 the Colordo  standard cannot be  considered in  the context  to long-term
public health protection,  since  it is neither well defined nor
conservative,   (p-5, line  22)
                                   174

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     Staff Response - The Guidance recommendations refer to dose rate
limits, and reference to a "soil standard" is inappropriate and
erroneous.

12.  Department of Energy

     The intended meaning of these two sentences is not clear.
(p-6, lines 4-10)

     Staff Response - The intended meaning is to acknowledge that the
Colorado standard may serve as a reasonable means of protection for
construction workers and that the objective of public health
protection is not given as its primary purpose.

13.  Department of Energy

     See Department of Energy comment of  page VI-1.
(p-7,  lines 23r25)

     Staff Response - The sentence states that "if  is  important  that a
detailed  environmental  impact evaluation  be made...prior  to
implementation."  The comment probably confuses  this  admonition  with
the  requirement  for  an Environmental  Impact  Statement.  The above
statement  again  illustrates  the  need  for  judgment  on  the  part  of the
implementing  agency.

14.  Department  of Energy

     This section considers  the  projected impact of guidance at
existing  sites.   Should there  not be  a  section that considers  the
impact at hypothetical  future  sites of  contamination, since this
Guidance  is  designed also to apply to future contamination events?
Several typical  accidents  should be  analyzed,  ranging from the maximum
 to a more normal release,  occurring  in  several types of areas.  This
would  indicate whether  costs are in  the range of thousands or billions
of dollars,  and given some indication of societal and environmental
 costs,  (p-8, Section IV)

      Staff Response - The agency staff believes that the consequences
 of potential accidents  should be considered in the Environmental
 Assessment of similar evaluations for specific facilities and/or
 activities (e.g., transportation of fuel elements), but not part of a
 generic guidance.      .        ,                       ,,,.<...

 15.  Jefferson County Health Department

      The report states that "the present maximum permissible  lung dose
 rate of one millirad per year is equivalent to about 100 times the
 current contamination levels derived from fallout."  This  can be
 contrasted with the Colorado standard, i.e..about 25  times fallout.
                                      175

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 I emphatically disagree that soil concentration data of plutonium at
 Rocky Flats indicates that offsite areas are "probably in compliance
 with the guidance."  This is not supported by survey data.  I would
 agree that "more intensive evaluation may be needed to determine the
 actual dose rates to the general population."  Again in Table 6-1, I
 would disagree with the estimates of the area contaminated offsite.
 My recent report to the Jefferson County Board of Health of a survey
 of the contamination over the entire area demonstrates a large area
 with contamination greater than 100 times background and a much larger
 area with contamination 25 times background level.
 (p-8, Section IV)

      Staff Response - The conclusion that offsite areas at the Rocky
 Flats Plants are "probably in compliance with the guidance" must be
 characterized as tentative and subject to confirmation.  It is based
 primarily on extensive environmental monitoring data by both the U.S.
 Department of Energy and the Colorado Department of Health,  and
 includes evaluations of air concentrations and soil contamination
 levels as input for suitable calculational models to derive  dose rates
 to exposed individuals.

 16.   Department of Defense

      Annexes V and VI devote little  effort to remedial  action  costs
 and  uses $500/acre as an estimated cost.   This  cost is  grossly
 unreasonable and  underestimates  actual  expense  involved in many cases
 for  existing sites.   A specific  example is Enewetak where  clean-up
 cost is  at  least  an order  of magnitude  greater.   Of equal  importance
 are  costs  that could be  incurred for sites  that  may be  contaminated  in
 the  future,  for a different  set  of circumstances could  be  involved.
 For  instance,  populated  areas might  be  involved,  requiring evacuation,
 personal property decontamination, stoppage of  industry, restriction
 of agriculture and  others.   Certainly,  this would  involve  costs
 associated with the  project  and  could exceed  the $500/acre associated
 by the EPA with the  proposed Guidance.  Would this,  if  considered,
 have made any  influence  upon the  level  chosen for  dose  limitation?
 Actual operating  experience,  at  least in  one  instance,  does not
 support  the EPA conclusion "...that  the cost  of  implementing the
 guidance at the reference  level would be  reasonable  and achievable".
 (p-10, Table VI-1)

     Staff Response - The agency staff  considers Enewetak  to be a
 special case that need not necessarily  fall under  this guide.  One
 reason is that  the restriction of access  to the  contamination  site is
 an option to be considered under this guide, but this option cannot be
considered for  Enewetak.  The $500 per acre is a minimum, and was not
intended to imply that all remedial measures can be performed at this
cost.  The recommended guide establishes what is believed to be an
acceptable level of risk at a cost that is not believe to be
                                    176

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unreasonably high.  Costs of treatment for existing and possible
future sites are discussed in the Supplement to the Proposed Guidance
and Dose Limits for Persons Exposed to Transuranium Elements in the
General Environment.

17.  Department of Energy

     Table conveys a false impression because of the unrealistic cost
estimate.  It also appears unreasonable that changing the "reference
level" by a factor of 3 could have such a major effect on the area
requiring remedial action.  (p-10j Table VI-1)

     Staff Response - Estimates of cost of remedial actions are
speculative at best and cannot be derived on a generic basis.  For the
relatively low environmental contamination levels  presently existing
outside  the boundaries of  these facilites, the costs of remedial
actions  could be  expected  to be of the order of magnitude stated.

     The estimates of areas defined within contamination contour  lines
were derived from published environmental monitoring data.

18.  Depatment of Energy

     Why is  the population of  the area relevant?   The  screening  level
seems  to be  independent of the number of  people affected.   Or  is  it  to
be understood  from  this  sentence  that such considerations are  relevant?
(p-11,  lines 5-6)

      Staff  Response - The  population  at  risk is a factor  in evaluating
the total  impact  of a given hazard.

 19.  Department  of  Defense

      Again,  the  $500/acre  cost is not generically realistic and  dose
not consider many factors  such as decontamination of buildings,
machinery,  homes, loss  of productivity,  planning, etc.
 (p-13, Section V)

      Staff Response - The $500 per acre figure was a minimum.   Costs
 of treatment for existing and possible future sites are discussed in
 the Supplement to the Proposed Guidance on Dose Limits for Persons
 Exposed to Transuranium Elements in the General Environment.

 20.  Department of Energy

      This section presents an inadequate consideration of costs of
 remedial action.  It says "the Agency has evaluated the'available_
 methods and costs" but does not tell how this was done, nor does it
 give any reference to this study.  The results are presumably
 summarized in Table VI-2, which is difficult to read.  It is clear,
                                     177

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 however, that in these estimates no consideration has been given' to
 costs of population evacuation, or monitoring;  decontamination of
 homes, roads, or commercial areas; income losses from cessation of
 agricultural or commercial activities;  cost of  Environmental Impact
 Assessment;  to mention but a few.   Nor  does it  give any consideration
 to environmental costs,   (p-13, Section V)

      Staff Response - The complete sentence reads "The Agency has
 evaluated the available  methods and costs for cleanup and restoration
 of contaminated land areag."  Most of the items cited may represent
 additional or extraordinary costs, and  do not necessarily represent a
 cost  of implementation of the Guidance.

 21.   Nuclear Regulatory  Commission

      Some NRC licensed facilities  are located in areas having other
 buildings and structures which would be  substantially more  costly to
 decontaminate than  for a facility  located in  a  remote area.   A recent
 "Draft Engineering  Evaluation of the Latty Avenue  Site,  Hazelwood,
 Misssouri",  by Ford,  Bacon,  and Davis, Utah,  Inc.,  dated January  1978,
 indicates that the  five  remedial action  alternatives  evaluated  for
 18,300 cubic yards  of contaminated material at  the  10 acre  site,  range
 from  $457,000 for clean  up  and  temporary storage  of contaminated
 materials on site to  $4,131,000 for the  alternative of disposal at  a
 commercial nuclear  waste disposal  site.   These  estimates  are
 comparable to the data presented in Table VI-2  of  the EPA Technical
 Summary Document,   (p-14, Table VI-2)

      Staff Response -  We  agree  that  this  range  of costs  is reasonable.

 22.   Department of  Energy                   ,    .

      Table requires a  number  (presumably  VI-2),  a title, enlargement
 to readable  size, and  particularly,  appropriate references.
 (p-14, Table VI-2)

      Staff Response - The basis, data, and content of Table VI-2 are
given in  Selected Topics: Transuranium Elements in the General
Environment", EPA Technical Note ORP/CSD-78-1 (1978).
                                   178

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                .4.  ESTIMATED COSTS OF REMEDIAL ACTIONS

4 • 1  Introduction

     The primary costs of implementing the Guidance are the costs of   >
bringing all sites exceeding the .recommended soil  limit into
compliance.  These include presently existing contamination sites as.
well as sites that may become contaminated in the  future.  The costs
of decontaminating presently existing contamination sites are believed
to be small, so that the major costs of implementation are expected to
be incurred in the event of future accidents or incidents that release
transuranium elements to the environment.  Since therpotential sites
of future accidents cannot be identified, a procedure is used for
estimating an upper limit to the expected annual costs of remedial    . j
measures.

     There are a number of difficulties in determining the appropriate
measures for .attaining compliance for contaminated lands.  The major
difficulty is that there has been little experience w.ith the.
decontamination of soils contaminated with transuranium elements.•    :
Thus there is little expertise for determining the appropriate action
to be taken to reduce the contamination level on a given piece of land
to an acceptably low level.  In addition, the determination of the
appropriate procedure requires information on site-specific factors
that are best, determined from on-site analysis by  persons familiar
with the task to be carried out and the, resources  available.  It  is
especially difficult to determine the appropriate  remedial measures
for new accidents, where it is important that prompt action be taken
to restrict dispersion of transuranium elements into the environment.

4.2  Cost Estimation

     Since the Guidance requires that the maximum  individual dose be
at or below a specified limit, and does not specify specific remedial
actions, cost-minimization is the appropriate criterion, to identify
the preferred set of remedial actions from the set of actions that.,
will bring the site into compliance.  The total cost of each possible
set of options that can attain compliance should be evaluated to
determine the least-cost method.  Environmental costs and other
non-monetary costs, not quantifiable in monetary terms should, if
possible, be considered in the evaluation.  Whenever feasible, it is
desirable that costs be quantified monetarily, but if this is not
feasible, they should be quantified in non-monetary terms.  Narrative
descriptions should be used when no quantification is possible.  A
difficulty is that different combinations of decontamination
procedures are expected to have somewhat different mixes of monetarily
quantifiable, non-monetarily quantifiable, and non-quantifiable
costs.  Judgment must be used in weighting the different elements of
these costs.
                                  17S

-------
      Most non-monetarily quantifiable and non-quantifiable costs are
 site specific.  Because of the great difficulty in estimating these,
 especially in the event of future accidents, only the monetary costs
 of implementation will be discussed here.  Cost of implementation is
 considered to be the monetary cost, on a nationwide basis, of
 performing the remedial measures sufficient to reduce the exposure to
 the critical segment of the population at each site to the recommended
 level.

      Two sources provide the unit cost estimates used in this
 evaluation,  an EPA study entitled "Available Technology and Unit Costs
 of Cleaning  Plutonium Contaminated Land Areas," and a document
 entitled "Department of Energy Comments on Decontamination Costs
 Discussed in the EPA Proposed Guidance On Dose Limits for Persons
 Exposed to Transuranium Elements in the General Environment"
 (Enclosure II to the Department of Energy's comments on the proposed
 EPA guide for transuranium elements in soil).   Table 4.1 is reproduced
 from the EPA study.   It summarizes the results of the study.

      The Department  of Energy has extensively  analyzed the costs of
 remedial measures for lands contaminated with  transuranium elements.
 Their estimates  are  used to supplement the EPA estimates because they
 consider a number of land use categories and decontamination
 procedures not considered in the EPA study.

      Table 4.1 summarizes the estimated costs  expressed in 1974  prices
 for  a variety of cleanup measures.   The costs  shown in Table  4.2 are
 derived  from Table 4.1,  but are adjusted to  1977  prices.
                                                                       i
      Although costs  of Table 4.1 have  been assembled to facilitate  the
 estimation of the  unit costs  of cleanup for  different  remedial action
 strategies,  the  costs  of individual  cleanup  procedures are also
 available  from the table.   Table 4.3 presents  the  individual  cleanup
 procedures costs  (adjusted  to 1977  dollars), derived from EPA
 estimates  (Table  4.1)  and  from DOE  estimates.  Most  of DOE's  estimates
were  taken from Table  14 of their Enclosure  II.I/   DOE costs  have
been  adjusted to  express  dollars  per acre.
I/  There are two errors in the costs shown in DOE's Table 14.  Both
are cost estimates credited to EPA.  The first is that EPA estimates
topsoil replacement to cost $4500 per acre, which is equivalent to
$1,112,000 per square kilometer rather than $562,200 per square
kilometer shown in Table 14.  The second is in the cost of fencing.
EPA estimates that fencing costs an estimated $30,000 per mile (1974
dollars) rather than the $3,700 per mile (i.e. $2,300 per kilometer)
expressed in Table 14.  Corrected cost estimates (adjusted to 1977
dollars) are shown in Table 4.3.
                                    180

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                                                                                                            TABLE   4.1


                                                                                               Decontamination  Costs
                                         EMICAL: VICETATIVE
                                                                                                                                                              VACUUM INC WITH TRENCH DI
   B. STA1ILJZATION
                       ;J RANGE OttJMO]
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                                                           [ASSUME:»1tafAI
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                                                                                                                                                                 IAKUKE: -
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                                                                                                                                                                                        [ASSUME: -BKVA1
                                                                                                                                                                                   «- COSTS INClUDt
                                                                                                                                                                                                                   OtS. ANO UNLOAOmC AT HJ
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                                                               'i-i1 S
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                                         SOIL A
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                                                                                                                                                                 AtlONI   BAMCE

                                                                                                                                                                PPLICATION iraO'KO
                                                                                                                                                                         <

                                                                                                                                                                                                                         j
                                                                                                                                                                                                                        3E
TOTAL NMMCT COSTS;
   ASSUU6D AVERAGES
     , -HANSES
       TION REMOVAL

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                                        4

                                    TABLE  4.2

                  Decontamination Costs Derived From Table 4.1
       Remedial Action
    Disposal
                                                             Estimated Cost,
                                                             (1977 Dollars)
Stabilization & Restoration Only
   Shallow Plowing
   Deep Plowing
4" Top Soil Cover
8" Loom & 4" Top Soil Cover
Scraping
Scraping
Scraping
Vacuuming
Scraping or Vacuuming

Scraping or Vacuuming
In Place
Dilution In Place
Dilution In Place
In Place
In Place
Windrows on Site
Mounds on Site
Trenches on Site
Trenches on Site
Off Site in State
 Repository
Off Site in Federal
 Repository
  2,400/A
  3,000/A
  2,850/A
  5,550/A
 11,050/A
    ,150/A
    ,900/A
  5,550/A
  6,450/A
4,
5,:
145,000 - 190,000/A

600,000/A
                                  182

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                                   TABLE 4'. 3
                   EPA and ,DOE Unit Costs of Decontamination
   Description
Short term stabilizer
Long term stabilizer
Vegetation removal
    Corn
    Other Crops
    Grass sod  /<,
    Slightly wooded
    Heavily, wooded:
Soil removal
    Scraping
    Front end loader
    Manual labor
    Vacuuming
    Scraping into ,
     windrows
    Scraping into,
     mounds
    Scraping into
     trenches
    Vacuuming with
     trench disposal
Soil replacement
    4"  topsoil
    4"  loam
    4"  topsoil  &  8"
       loam
    12"  loam
Shallow plowing (12")
Deep plowing  (36")
Deep plowing  of pasture
  land
Restoration
     Fertilizer

     Lime
     Mulch
     Seeding
     Seedlings
     Shrubs
EPA
Estimated
Cost
810/A
690 /A
NE ,«»)
NE
580/A
1,440 /A
2, 300 /A
950/A . ,
. NE .-•
..•NE
1,2(1Q/A
230/A
690 /A
1,960 /A
2, 890 /A
5, 180 /A
2,670/A
10, 700 /A
8, 280 /A
50 /A
230/A
NE
170/A A
25 /A
140 /A
230/A
70 /A
1,500 /A
DOE1"8'
Estimated
Cost
$ 300 /A
420 /A
80 /A
16/A
920/A
NE
NE
920/A
- , 1,700 /A
2,900/A
NE
NE
NE
NE
NE
6, 500 /A
NE
NE
NE
14/A
140/A
610/A
270 /A
NE
NE
NE
NE
NE
  DOE Definitions
          and
     :  Assumptions

Two weeks water fixation
Long acting stabiliser
Field sod removal ,
Grader
 25cm 'depth
 1 meter depth

 Includes reseeding

 Includes seed (materials
  only)
 See "Fertilizer"

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                              TABLE 4.3 (continued)
 Biobarrier
 Lawn sod removal
 Vacuumized sweeper for
  streets
 Fire hosing
 Decontamination of
  homes
 Lawn resodding
 Decontaminating
  commercial areas
 Fence (based on
  perimeter length)
 Surveillance (based
  on  perimeter length)
 Offsite  disposal
  (including packaging)
  and  1000  miles tran-
  portation)
      Federal Repository
      State Repository
        NE
        NE

        NE
        NE

        NE
        NE

        NE

   34,500/mi

        NE
586,500/A
138,000/A
  72,000/A
   1,140/A

    160/A
    200/A

    350/House
   5,200/A

   3,700/A

  75,600/mi

   9,700/mi
482,500/A
 59,500/A    Commercial
              repository
(a)  Taken from DOE Enclosure II, Department of Energy Comments on Decontamina-
     tion Costs Discussed in the EPA Proposed Guidance on Dose Limits for
     Persons Exposed to Transuranium Elements in the Environment, Table 14.

(b)  NE - No estimate.
(c)  Cost taken from document sited above.
     Table 10,  p. II - 18
                  Reference found in footnote (a) to
                                  104

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     The two agencies' costs can be compared for those cases where
both made estimates.  The Table 4.3 shows that most estimates  are
within a factor of three.  Although this is a rather big difference,
it is no larger than might be expected considering the lack.of
experience with this form of decontamination.  There is no  apparent
uniformity with respect to which agency's estimates are the higher.
It can, therefore, be considered that EPA and. DOE do not greatly
differ in their estimates of the costs of the individual procedures
that must be undertaken to restore transuranium contaminated  lands.

     There are two general techniques for restoring lands  to
unrestricted use:  (1) all land surface  soils are removed  and
transported to another location for final disposal; and  (2) plowing,
which leaves the  contamination in place, but lowers the  concentration
levels in the top most land  surface. . When  the  surface  soils  have been
removed, they may be  stored  on-site,  or  off-site  in state  or  Federal
repositories.  On-site storage is an  option that  can be  used, where a
part of  the site  can  be  reserved for  the disposal of  the^surface  soils
removed  from other portions  of the  site.   In most cases  it is
estimated that no more than  5% to  10% of the site  is  needed for the
disposal of the  contaminated surface  soils  removed  from the remaining
90  to  95% of the  site.   The  part of  the  site used for  disposal must be
purchased and permanently subjected  to.controlled  access,  but there
would  be unrestricted access to  the  remainder  of  the  site.  An
alternative that  could be used  for  lands adjacent  to  a Federal
 facility would be that a portion of the  facility  grounds be reserved
 for the  purpose'  of  on-site disposal.   On-site  storage avoids  the
extremely high costs  of  off-site storage in state or  Federal
repositories.  Tables 4.1,  4.2  and  4.3  pr.ovide estimates of the costs
of  on-site  disposal.   DOE did not  consider this type  of treatment.

      Land  use  restrictions for  entire contamination sites  should be
 considered  if  such restrictions  are the least, cost option, although
 the circumstances of each particular site must be evaluated.  Costs
 include acquisition of the site, the costs of fencing, guards, and any
 other measures  required to maintain restricted access.  Costs also
 include all remedial measures that may be  required on the  restricted
 area to prevent  dispersion of the contamination to areas outside  the
 restricted area, such as stabilization, plowing, the .development  of
 on-site storage  in trenches., windrows or mounds, and the establishment
 of ground cover.  Costs would also include the dismantlement,of  houses
 or other facilities that may be on the^site.                          .

      Land use restrictions  are a form of remedial action  cost not
 quantifiable in  dollars.' Such restrictions are likely to  impede the
 natural flow of  traffic  in  the community in which they are used; and  to
 block its orderly development.  Also, the  restricted areas are likely
 to become despositories  of  trash and other waste as well  as become
 overgrown with weeds unless there are ongoing maintenance  programs.
 The disruptive nature of land use restrictions is so  important,
 especially in urban  or  industrialized areas, that they are probably
 feasible only in localities of low population  densities where there
 are few or no known  alternative uses for  the  land.


                                    185

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                                    8

      DOE analyzed^the cumulative costs of  remedial  action at  three
 real (but unidentified) sites.  Two area sizes were used at each  site
 for a total of six sets of costs.  The two sizes considered were
 1km  and 10km2.  These sites are devoted to a number of uses,
 including crops, orchards, pasture, woodlots, forests, shoreline, and
 residential and commercial areas.  The areas analyzed are quite large;
 large enough that DOE's cumulative decontamination costs are  not
 realistic estimates of the cost of future accidents.  Therefore,  the
 total costs expressed in the third column of Table 4.4 are not useful
 for estimating the costs of future accidents.  However, when  these
 costs are expressed as functions of unit areas (i.e., $/km2 or $/A),
 they serve as possible estimates of the average unit costs of future
 accidents.

      The last column of Table 4.4 summarizes  the average unit costs
 for the  six sites analyzed by DOE.   Most of the content of this table
 was taken from Table 13,  Enclosure  II.  Alternative methods of
 treatment are given in the second column.   Site restriction refers to
 the purchase of all  lands  and the maintenance of fences to restrict
 access  to the entire contamination  area and to the  measures needed to
 prevent  dispersal of transuranics.   The other three treatments refer
 to  the remedial action taken  on open lands, where earth removal for
 off-site storage,  shallow  plowing,  and deep plowing are alternatives.
 The remedial measures  on all  portions  of  these sites that  cannot be
 plowed are  the  same  for all three treatments.   Reference  site  2 had  no
 open lands  that could  be plowed.

      The mean and  standard deviation  for  the  four sets  of  remedial
 actions  on  the  six sites are  shown  at  the bottom  of  the  table.
 Comparison^of these values shows  that  for similar treatment  strategies
 there^is  little difference in the average costs of  treatment for the
 six sites, but  that  there are comparatively large reductions in costs
when  open lands are plowed.  This demonstrates  that measures that
avoid the high  cost of soil removal for final  disposal  in a state  or
Federal  repository can significantly reduce the cost of remedial
action.  Calculations based on DOE's Table  11 and 12 (Enclosure II)
show that off-site disposal at Federal repositories accounts for 82 to
98% of the costs of treating the six sites when earth removal  is the
treatment strategy.
                                  186

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                                      .9

                   .  .,. .             TABLE 4 .A

                  Comparison of Estimated Cumulative Costs per
                    Unit Area for All Sites and Treatments*
      Area

1.0 km2:
 Reference. Site One
 Reference Site Two
 Reference Site Three
10.0 km2:
 Reference Site,One
 Reference Site Two


 Reference Site,Three
                       Treatment
                                (a)
                                          Total Cost
                      Cost/acre
($ Million.1977)   ($ Thousand 1977)
ER
SR
;, DP
SP
. ER
. SR
ER
. SR
DP ,
SP
ER
SR
, . DP
SP
ER . .
SR
ER .
SR ;
DP '
SP
115.6
95.2
, 12,9
11.4
93.3
133.5
.121.2
95.4
, 21.2
19.5
11.2.7 .0
1062.4
159.5
145.2
, 1103.1
1080.7
1213.0
'.,'..-' 942.7
144 . 8
128.5
                         468
                         385
                          52
                          46

                         378,
                         540

                         490
                         386
                          86
                          79

                         456
                         430
                         ; 65
                          59

                         446
                         437

                         491
                         382
                          59,
                          52
Average  cost,,  earth removal  (6 sites)  = $454,000/A;  standard deviation
   =  $42,000
Average  cost,  site  restriction (6 sites) - $427,000/A;  standard deviation
   =  $61,000                                                        . •  • .
Average  Cost,  shallow plowing (4 sites) = $59,000/A; standard deviation
   =  $15,999
Average  cost,  deep  plowing (4 sites) = $66,000/A; standard deviation
   =  $15,000
 "^  ER = Earth removal to depth of 5 cm; DP = Deep (1-m) plowing; SP = Shallow
        (25-cm) plowing; SR = Site restriction, including construction of a
 biobarrier.

 *Source:  Enclosure II, Department of Energy Comments on Decontamination Costs
  Discussed in the EPA Proposed Guidance on Dose Limits for Persons Exposed to
  Transuranium Elements in the General Environment, Table 13.
                                    1 P^7.

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                                     10
 4.3  Recommended Action Levels
       It would be  useful  to  establish  the  contamination concentration
 levels at which different remedial  actions  are  appropriate.   Since a
 variety of circumstances bear  on  the  determination,  no universally
 applicable rules  can be  established.  There is, however,  some
 information for establishing the  appropriate  levels  where  some  forms
 of remedial action may be considered.

      The threshold of remedial action is  established by the
 recommended soil  screening  level  of 0.2 uCi/m2.  No  remedial  action
 need be undertaken, for  sites with soil concentrations  below  this
 level.

      The Department of Energy has established that shallow plowing
 (i.e. 10 inches) reduces the surface contamination by a factor of 5,
 to 20% of its former level, and that deep plowing (3 feet) reduces it
 by a factor of 20 to 5% of  its former level .I/

      Based on these estimates, and on the recommended soil screening
 level, it can be established that a contamination level equal
 1.0 uCi/mz (before remdial action) is the upper limit for lands for
 which shallow plowing is sufficient to bring the site into compliance,
 and 4.0 uCi/m^ is  the upper limit for which deep plowing will attain
 compliance.   Plowing is, of course, a viable option only for open
 lands where  soil characteristics permit.   Since deep plowing will
 bring sub-surface  soils  to the surface,  some form of restoration, such
 as a soil  cover  of topsoil  or  loam may be required.

      EPA estimates that  land with a surface contamination below 10
      2 (before remedial  treatment) may be safely stored on-site in
 windrows, mounds or  trenches.   Such on-site storage  requires that
 access  to  the  storage  area be  controlled  and that measures be taken to
 stabilize  the  surface  soils  from wind  and water erosion.  Controlled
 access  is required to  assure the  soil  surface  is not  disturbed and
 that  the integrity of  erosion prevention  measures  is  maintained.

      Other remedial measures are  required  for  sites contaminated  above
 10 uCi/m/.  The most likely  is  the removal of  the surface  soils  for
 transport to state or Federal repositories.

      It is possible that  some of  the very  high  costs  of storage at
 state and Federal  repositories  can be  significantly reduced by methods
 that  concentrate the contamination, reducing transportation and
 storage costs.  Concentration has  been demonstrated for  plutonuim,


J7Appendix C, pg. 6-4
                                  188

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where the major fraction of the plutonuim is,generally attached to the
smallest sized-soil particles..,This leaves the larger particle sizes,
which usually constitutes the major fraction of the soil, relatively
free of contamination.  This subject is more fully discussed in Annex
II to the "Proposed Guidance on Dose Limits for Persons Exposured to
Transuranium Elements in the General Environment."

     As discussed in the "Proposed Guidance", the soil screening level
is conservatively chosen to provide that the recommended dose level .be
met for the most adverse soil characterstics.  The recommended action
levels have the same conservatism.  Since these action levels are
conservative, the circumstances of a particular site may be such that
plowing or on-site storage may achieve the recommended dose limit for
sites contaminated above the action levels derived here.

^•4  The Cost of Implementing The Guidance       ,

     There are two components to the costs of implementation.  The
first is the cost of bringing presently existing sites into compliance
and the second is the cost of remedial measures undertaken for
accidents that may occur after promulgation of this Guidance.

4.4.1.    The Cost of Implementation on Presently Contaminated Sites

     There are four Federal sites in the United States that presently
have transuranium element contamination above ambient levels beyond
their boundaries.  These include the Rocky Flats Plant in Jefferson
County, Colorado, Mound Laboratory in Miamisburg, Ohio, Nevada Test
Site in southern Nevada, and Trinity Test Site near Alamogordo, New
Mexico.  The majority of all contamination released is confined within
areas under the direct control of the Federal government, which
imposes restrictions on the access and use of these areas,.  Relatively
small amounts of transuranium element contamination exists outside the
boundaries of these sites on lands generally accessible to the
public.  The following discussion is intended to supply a perspective
for applying the Guidance recommendations to these sites in terms of a
soil concentration reference level derived on the basis of generic
data, which, with a very high degree of probability, would be expected
to result in an inhalation dose to an individual not to exceed the
Guidance recommendations.  Use of such a soil contamination level is
intended solely to provide a basis for comparisions and does not imply
direct correlation with the dose rate recommendations.  A brief
description is given for each site and the general contamination
pattern is indicated.  Numerical comparisions to show the estimated
areas of limiting contamination to one-third and one-tenth the
reference level, and of allowing a value ten times greater than the
reference level are given in Table 4.5.  Comparisons are made in terms
of areas outside the boundaries of these sites.
                                     189

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                                    12

     The Rocky  Flats  Plant  produces  components  for nuclear weapons.
Barrels containing  cutting  oil  slowly  corroded  and some of the
contents eventually leaked  into the  environment and were dispersed.
On  the basis  of soil  concentration data,  all  off-site  areas at the
Rocky Flats Plant would  probably be  in compliance  with Guidance
recommendations.  However,  more intensive evaluation may be needed  to
determine  the actual  dose rates to the general  population, ,
particualarly in the  most highly contaminated areas east of the
plant.  The area is sparsely  inhabited and there are few people living
in  the particular area of concern.   The off-site area  contaminated.to
a level one-tenth the screening level  comprises about  1.6 mi2  with  a
current population  of less  than 600.   No  uncontrolled  areas are
contaminated  to a level  greater than ten  times  the screening level.
All local  water supplies are  expected  to  yield  ingestion dose  rates
well below the  Guidance  recommendations.

     Mound Laboratory is a  major research and development site for
fabrication of  radioisotopic  heat sources used  for space and
terrestrial applications.   In 1969 a pipeline transporting a Pu-238
waste solution  ruptured, spilling the  contaminated solution.   The
plutonium  migrated  slowly into  nearby  waterways.   The  majority of the
plutonium  is  now sorbed  and fixed on the  sediments of  the North and
South Canals.   Maximum concentrations  are to  1  to  3 ft.  below  the
sediments  surface and currently do not pose any radiation problem,
since very little of  the plutonium is  in  soluble form  and the  canal
water is not  used for drinking  purposes.   Banks immediately adjacent
to the canal  and overflow creek subject to occasional,  flooding have
maximum plutonium concentrations  exceeding the  reference level.  The
amount of  land  in question  is about  0.01  mi2  and there are no  people
living on  this  land.  There are no areas  with transuranium element
contamination 10 times the  screening level.   The amount  of land
contaminated  to one-tenth the screening level is the same as the
amount of  land  above  screening  level,  because the  nature of the
contamination event limited the contamination to the waterways  and
adjacent banks.  No immediate cleanup  is  indicated for this site, but
continued  surveillance will be  required.

     The Nevada Test  Site covers  an  area  of 1400 mi2 with additional
exclusion  zone  extending 16 to  48 miles.   Major programs at NTS have
included.nuclear weapons tests,  testing for peaceful uses of nuclear
explosives, and nuclear  reactor engine development.  These activities
have resulted in plutonium  contamination  in certain areas of the test
site and exclusion  areas and  slight  contamination  (above background
levels) outside the exclusion areas.   There are no known uncontrolled
areas which have transuranium element  contamination exceeding  the
reference  level.  Land contaminated  to one-tenth the reference  level
or less covers  approximately  165 mi2 with a resident popluation of
less than  240 people.
                                   190

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     The Trinity Test Site was the location of the  first nuclear
explosion.  No other nuclear explosion tests were performed at
Trinity.  A site survey was performed by EPA during 1973-74 to
determine residual plutonium concentration contours.  The highest
plutonium comtamination levels in uncontrolled areas  ranged from 0.2
to 0.9 uCi/m2.  The amount of land contaminated  to  a  level one-tenth
the reference level covers less than 300 mi2, with  fewer than 500
people living in the area in small towns, ranches,  and  farms.   On  the
basis of the limted available data, no major remedial actions would
appeal to be indicated for this site.

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                                        14
                                   TABLE 4.5
         Areas of Existing Sites Requiring Remedial Action for  Several
                 Possible Levels of Maximum Soil Concentrations

       Reference Level   10 Ref. Level  1/3 Ref. Level     1/10  Ref.Level
0.2 uCi/i
Rocky
Flats
Plant

Neveda
Test
Site

Trinity
Site

Mound
Lab.
                                         0.07
   200 Acres
51.000 Acres
13.000 Acres
     6 Acres
                  0.02
                                                   1,000 Acres
                                                 106,000 Acres
                                                 192,000 Acres
                                                       6 Acres
                                 192

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                                   15,

     In summary, it appears that few if any remedial measures are
presently needed on the four sites identified in Table 4.5, although
some action may be required when the canals.at Mound Laboratory  are
drained.  Therefore, the costs of meeting the Guidance for presently
contaminated sites are expected to quite low.                        " . -

     An assumed minimum cost of $500 per acre for remedial action was
the basis of the discussipns in the "Proposed Guidance on Dose Limits
for Person Exposed to Tansuranium Elements .in the General
Environment".  This cost was introduced to  demonstrate that, even if
costs of remedial action were as low as $500 per acre, the costs of
proposing a dose limit equivalent to a screening level substanially
lower than 0.-2 uCi/m^ would be prohibitive.. However, it is
recognized that realistic estimates of costs of implementing the
Guidance ordinarily must be based on unit cost estimates that are much
higher than $500 per acre.

4.4.2.   Considerations for Estimating the  Costs in  the Event of
Future Releases of Transuranium Elements  to. the Environment

     Strictly conceived, the costs of remedial measures required to
implement this Guidance for potential future accidents are the costs
over and above those that would have been undertaken in the absence  of
this Guidance.  Unfortunately, this difference, cannot be estimated.
Therefore, to the extent that costs of required remedial measures can
be estimated, they will be assumed to represent the  costs of
implementation.

     The remedial measures available for  the treatment of soil in case
of future accidents are expected to be shallow or deep plowing,  and
soil removal with storage on-site, or in  state or Federal
repositories.  In urban or industrial areas, houses,  buildings,
streets, and sidewalks may require decontamination.   Temporary
evacuation of the population may be also  necessary.   An alternative  to
restoring the land to unrestricted use is its acquisition, and the
imposition of restricted access with possibly some  form of remedial
action undertaken on the site.

     Although little can be done to anticipate the  form of future
accidents involving transuranium elements,  they should  impact  on areas
more limited in size than the largest of  the presently known  sites,
which were caused by above ground tests of  nuclear  weapons.   Since
similar  tests are unlikely in the foreseeable future,  future
contamination should be confined to areas smaller than  the
contaminated areas at the Trinity and Nevada Test Sites.   It  is  to  be
expected that increased alertness to the  problems of transuranium
element  contamination will substantially  reduce the reoccurrence.of
events  such  as Rocky Flats, where the delay in treatment aggravated

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                                    16

 the situation.  There is also reason to believe that increased
 awareness to the health hazards from transuranium elements has
 resulted in expanded effort to prevent the occurrence of such
 accidents.  These measures should help to assure that the areas
 impacted in future accidents will be small.         •         •
                                  ''     .         '          .      ','''.
      The costs' of remedial action in the case of future accidents are
 correctly conceptualized as the "expected costs" of the measures
 undertaken for all future events,that release transuranium elements to
 the environment.  As used here, the term "expected costs" is analogous
 to the statistical concept "expected value".  Since there is at least
 a small probability that any of a large number of possible events
 releasing transuranium elements to  the environment could occur in the
 future, and since there is a virtually limitless variety of factors  ,
 contributing to the possibility of  such events, expected costs are the
 appropriate measure of the costs required by the Guidance.

      It can be argued that expected costs are the proper way to
 consider the problem from a societal point of view.   Society is
 subjected to innumerable forms of financial risk from a variety of
 events.  The events can be assumed  to occur randomly;  therefore the
 evaluation of the costs  incurred because of such events should take
 into  account the estimated probability of their occurrence  as well as
 their costs when they do occur.   Since the accidents that may release
 transuranium elements to the environment also .occur  randomly, the
 costs  of required remedial action are one of these financial risks.

      Probabilistic expressions of the chance of future  accidents
 involving the release of transuranium elements,  and .of  their size and
 the types of land to'be  impacted are needed to  evaluate expected costs.

    , Another factor that may enter  into  the evaluation  of the costs  of
 implementing this Guidance is  whether present worth  methods  should be
 employed  in 'estimating the costs of possible accidents  that  may occur
 sometime  in the  future.   If so,  the estimated distribution of tli.e
 probability of  occurrence through time would be needed.   Since  no
 attempt'has" been made to estimate this distribution, present worth
methods are not  used  here.          ,  ;

4.4.3.    The  Cost of  Implementation in the  Event  of 'Future Releases  of
Transuranium Elements  to the Environment

     Although it  must  be concluded  that  there is  insufficient
information  at  this time to estimate  the  costs of  future  accidents,  it
may be  useful to  assume  some values  that  place an  upper  limit on  the
expected  cost of  implementing  the Guidance.  The basic premise
underlying  this estimate is  that the  expected annual contribution  to
new contamination from accidents or other unforeseen events  releasing
transuranium  elements  to the environment will not exceed  four acres.
This establishes  an upper  limit  to  the expected costs of  implementing
this Guidance for  cases  of  future contamination.
                                     194

                                      17

        It is  realistic  to expect that accidents of all sizes can occur.
   Therefore,  it  is  assumed that the size of the area contaminated in a
   single accident varies, as  does the number of accidents occuring in a
   year's time.   The Figure 4.1  represents a possible distribution for
   the  expected  total number of  acres contaminated in a year's time.   The
   land area requiring remedial  action is shown on the horizontal axis
   and  probabilities are shown on the vertical axis.  The number of acres
   that can be contaminated in a year's time ranges from zero upwards.
   The  right hand tail of the  function is .infinitely long, expressing
   some probability  (although  small) that the number of acres
   contaminated  in any single  year may be quite large.  For example,  for
   the  distribution  shown here,  there is an 8% probability that the land
   area contaminated in  any one  year will exceed 10 acres.  This
   distribution has  an average value of four acres.
                                 FIGURE
o
c
0)
3
O1
0)
10
3
C
C
                                        10
12   14    16    18    20
                  Land Area Contandnated per Year (acres)
                                       195

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                                    18

     Although  the  distribution represented in the figure is
speculative, it  does  incorporate  the intuitively desirable feature
that there  is  a  rather high  probability  that  the total  area
contaminated by  the accidents  in  a  year's  time is small, and that the
probability declines  as  the  area  contaminated increases.

     An upper  bound estimate of the costs  of  the remedial action
required because of these  accidents is derived by assuming that the
concentration  of transuranium  elements is  sufficiently  high that all
surface soils  must be removed  and disposed of in Federal repositories.
Assuming the costs of doing  this  are equal to the average for the cost
of remedial action on the  sites investigated  by DOE,  the average cost
of remedial action would be  $454,000/acre  (Table 4.4),  and the
expected annual  cost  of  remedial  action  would be four times $454,000
or $1,816,000.

     In using  per  acre costs based  on the  DOE analysis,  it is assumed
that the areas contaminated  are diversified in that they contain a
variety of  land uses, and  may  contain residential and commercial
areas, as well»as  agricultural and  wooded  areas.   The six large areas
in which these averages  are  based provide  sufficient  diversity so that
the per acre costs are considered to be  representative  of the types of
lands that  may be  impacted in  the .case of  a future accident.

     If the assumptions  underlying  the per acre cost  estimate are
changed by  assuming that the concentration of transuranium in the soil
is low enough  that plowing is  adequate treatment for  all open areas,
the DOE estimates  show that  the unit costs of treatment  would be
reduced to  $59,000/acre, and the  expected  annual cost would be reduced
to $236,000.

     These  values  establish  the range $236,000 to $1,816,000  for the
expected annual cost  of  implementing this  Guidance in the event of
future accidents.

     In cases  where the  level  of  contamination is sufficiently high
that shallow plowing  is not  adequate to meet  the recommended  Guidance,
alternatives other than  storage in  Federal repositories, (i.e.  deep
plowing, on-site storage or off-site storage  in state repertories) may
be considered.  In those cases  where these methods prove to be
adequate, the  estimated costs  of  remedial  action are  expected to fall
somewhere within the  range of  costs established here.

     There  is, however, evidence  that the  low end of  this range is
itself high.   This is because  the low estimate of the upit costs of
implementation (from Table 4.4). was for  the case  where all .open lands
were plowed, but where the surface  soils from areas that could not be
plowed were removed and  transported to Federal  repositories.
                                  136

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                                    19

Comparison of  the  costs  of  storage, in  Federal  repositories  with the
costs of  storage in  state repositories or>storage  on-site  (Table 4.3)
reveals that substantantial  savings can be  realized  when the
contamination  level  is low  enough  that these types of  remedial  action
can be used.   Therefore, the low end of this range could probably be
lowered,  at least  to  some extent.

     The  range of  costs  established here is based  on an  average annual
contamination, of four acres.  Historical evidence  indicates that this
value is  probably  high.  The  United States has had over  30  years of
experience with activities  involving the use of  transuranium
elements.  These activities  have been  carried  out  at a large number of
locations.  Nevertheless, problems  have been identified  at  only the
four sites discussed  in  Section 4.1.   As discussed there, it is
believed  that  little  or  no  remedial action will  be required to  bring
these sites into compliance  with this  Guidance.  Even  though activties
involving the  handling of transuranium elements  are  expected to
increase  in the future,  past  history,  and increased  awareness of the
danger from the release  of these elements to.the environment, gives
reason to believe  that the annual expectation  of four  acres of  new
contamination  assumed here may be high.

     In summary, the annual  costs of remedial  action in  the event  of
future releases of transuranium elements to the  environment is
expected  to range  from $236,000 to  $1,8167000.   Nevertheless, there is
reason to believe  that this  range may  be high, and that  future  costs
will be lower  than estimated.
                                     197

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                      5.  GUIDANCE IMPLEMENTATION
5.1  Int sroduc t ion
     Implementation of the Guidance recommendations involves
consideration of all transuranium element environmental contamination
and pathways that could result in radiation doses to persons in the
general population.  Such a consideration includes a determination of
the level and extent of existing contamination.and the projections of
actual or potential doses to a critical segment of the exposed
population.  This requires an evaluation of the site, a projection of
the radiation dose rates via all applicable pathways to determine
whether Guidance values are exceeded, and initiation of remedial
actions where indicated.

     Implementation of the Guidance recommendations is the
responsibility of those agencies having regulatory and administrative
responsibilities for the site in question and/or the materials in use
at a site.  A reasonable evaluation of a contaminated site should
include a description of the site and environmental measurements of
contamination levels in environmental media, in sufficient detail to
convey adequate information to the general public.  Environmental
pathway and dosimetry models used to estimate radiation doses to
persons should be described to permit evaluation of the procedures
used.  If projected dose rates are greater than the recommendations3
protective or remedial actions should be performed such that Guidance
values are not exceeded and will not be exceeded in the foreseeable
future.        '        •          .  '             ...'...'..

     In the context of this Guidance, the objective of environmental
sampling and analysis is to derive information for the purpose of
estimating dose rates to pulmonary lung and to bone of exposed
individuals,  these dose-estimates are derived on the basis of models
which consider the various pathways by which transuranium elements in
the environment may interact with people and produce exposure to
radiation.  Such models describe the characteristics of transuranium
elements in the environment, the manner in which they may be
transported through the air or through food pathways, modes of
interaction with man (including inhalation or ingestion) and, finally,
factors related to the radiation energy deposition in organs and
tissues.  In general, dose estimates are best derived from data
acquired from measurements in the dose pathway as close as possible to
the point where transuranium elements interact with people.

     Three general procedures can be used to judge compliance with the
Guidance recommendations.  These procedures, which are described in
more detail in the following sections, may be used for the entire site
or for portions of the site as appropriate:
                                  199

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     a.  dose rates can be  calculated,  using  the  appropriate  dosimetry
models, from measurements of  the  concentration of the  transuranium
elements in air,  food, and  water  at  the point of  inhalation and/or
ingestion by persons.  This is  the most direct and preferred  method.

     b.  soil concentration levels of  the  transuranium elements  can be
compared to a "screening level" for  soil,  defined as that  level  below
which the concentration of  the  transuranium elements is not likely to
lead to dose rates in excess  of guidance recommendations.

     c.  dose rates can be  calculated  from the soil contamination
levels of the transuranium  elements  using  site-specific parameters for
transport models  and the appropriate dosimetry models.

5.2  Implementation of Guidance by Estimating Dose Rates to Lung and
     Bone

     Federal agencies may show compliance  for a specific site, or  for
sub-areas of a specific site, by  certifying that  Guidance  values for
dose rates to the lung and  bone of members of the critical segment of
the exposed popoulation are not being  exceeded.   The most  direct
method is to measure transuranium element  concentrations in
environmental media such as air,  food,  and water  at the point of
interaction with  people and then  to  calculate the potential radiation
dose rates using  the appropriate  dose  conversion  factors and  dose
model parameters.  When this  procedure  is  used, adequate documentation
should be provided to demonstrate how  dose rates  are calculated.   The
Agency favors the use of realistic environmental  measurements and
realistic mqdel input parameters; conservative parameters  should only
be used to the extent necessary to compensate for uncertainties.

     In certain cases, compliance with  the Guidance recommendations
may be achieved by restricted occupancy of a site,  or  portions of  a
site.  Time restrictions for  occupancy,  or other  use limitations,  may
be established to limit the exposure of a  critical  segment of the
population.  Such occupancy or use restrictions should be  applied  only
if remedial actions sufficient to permit unrestricted  access  are
either impossible or economically prohibitive.

5.2.1    Dose Rate to the Lung

     Lung dose rates are calculated  using  appropriate  dosimetry
models, which require knowledge of the  annual average  transuranium
element concentration in air, aerosol  particle size distribution,  and
solubility class of the specific  radionuclides present.  Apparatus and
procedures for the  sampling  and  analysis  of particulates  in  air are
available, but the accuracy and precision of measurements  must be
verified prior to implementation  of  the  guidance.
                                  200

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      Judgment should be exercised in the:desigri of an air sampling
 program to ensure that air concentration levels are representive of
 actual exposure conditions.  Environmental measurements of airborne
 particulates which bias the dose estimates by the collection of only
 certain particle size ranges should be avoided, or a suitable
 correction should be made.  It is preferable that the particle size
 distribution be experimentally measured for a specific site.
 Reasonable values can be assumed based on analogies with similar sites
 when projected lung dose rates are small compared to the Guidance
 level.  The solubility class of an aerosol can usually be determined
 from the history of the contaminating event and the subsequent
 environmental weathering mechanisms.  Dose conversion factors for lung
 dose rates that the Agency believes to be reasonable for the purpose
 of implementation of the Guidance were presented in Annex III.

      A derived air concentration "screening level" which if not
 exceeded indicates with high probability that the guidance
 recommendations will not be exceeded, may be substituted for a
 site-specific air concentration limit.   The agency suggests that such
 a  derived air concentration "screening level" be based on an activity
 median aerodynamic particle diameter (AMAD) not to exceed 0.1 urn,
 which is substantially smaller than observed values at all sites where
 transuranium element contamination presently exists.   The calculated
 limiting concentration for this procedure would be about 1 fCi/m3 of
 alpha emitting transuranium nuclides, for air samples  averaged over a
 period of one year or more.   Air concentrations above  this value do
 not  necessarily mean that  the Guidance  recommendations may be
 exceeded,  but rather this  dictates that a more  thorough evaluation of
 existing conditions  should be made.

      Elevated levels of transuranium elements  in air  indicate that
 these  elements  may be found  in nearby soils.  When these levels
 approach  that of the Guidance  recommendation,  implementation  should
 include  a  characterization of  the  environmental  source term,  to
 provide  a  means  of judgment  with  respect  to the  potential  for future
 exposure  levels  and  the  practicality of remedial measures.

 5.2.2    Dose Rate to the  Bone

     Bone  dose  rates  are calculated  with  appropriate dosimetry models
 using  a knowledge  of the average amounts  of transuranium elements  that
 are  ingested  in a  year,  their  chemical  state  at  the time of  ingestion,
 and  the proper  dose  conversion factor.  Inhalation of  transuranium
 elements,  especially  in  soluble  forms,  can  also  lead to  radiation
 doses  to bone  and  should be  considered  where appropriate.

     Sampling and measurements  of  transuranium elements  in food  and
water  at the point of human  consumption is  the most direct and
 preferred  procedure  for determining  the annual average  ingested  amount
                                  201

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of these elements.  Alternatively, the amounts of ingested
radionuclides may be estimated using environmental pathways models.
The chemical state at the time of ingestion  is inferred from the
medium in which the transuranium elements are incorporated.  In
particular, transuranium elements which are  incorporated into
biological tissue should be considered as "organically complexed"  and
require a special dose conversion factor.  Dose conversion  factors
that the Agency believes appropriate for the implementation of this
Guidance with respect to bone dose rates were given  in Annex III.

     Suitable sampling and analytical procedures are available for the
analysis of the transuranium elements in food and water.  As with  the
inhalation pathway, elevated levels of plutonium and the transuranium
elements in food  or water indicate that these elements may  be  found in
nearby soil or in sediments.  Under such conditions, implementation of
the Guidance should include .a characterization of  the environmental
source term, to provide  a means of judgment  with respect to the
potential for future exposure levels and the practicality of remedial
measures.

5.3  Implementation of Guidance by Use  of  a  Soil "Screening Level"

     Federal agencies may  show  compliance  for the  total  area of  a
site, or  for subareas  of a  site,  by  certifying  that  such areas have
transuranium element  soil  concentration levels  less  than a  "screening
level" value of  0.2 uCi/m2.   The  "screening  level" is a total
transuranium element  soil  concentration level in the top  1  cm  of soil
such  that,  in  the Agency's  opinion,  dose  rates  will  not exceed
Guidance recommendations under  the  vast majority of  land  use
conditions.  When this  implementation  mechanism is used,  all lands
subject  to  unrestricted  use must  meet  the  screening  level  criteria.
Because  of  present  uncertainties  in the amount  of plant uptake for the
more  soluble  transuranium nuclides,  such as  americium and  curium, and
 the resultant  possibility of larger doses  via the ingestion pathway
 than  calculated, the "screening level" concept may not be applicable
when  the soils of a contaminated area contain these nuclides in
 amounts  greater than 20-25% of the total activity.  Lands  with
 concentration levels less than the "screening level" are judged to be
 suitable for all normal activities including residential and
 agricultural uses.   The use of this "screening level" is intended to
 reduce the land areas requiring extensive evaluation and to minimize
 the number of measurements needed.

      If land areas have transuranium element levels  greater than  the
 "screening level," it should not be presumed that Guidance values are
 necessarily exceeded, because conservative  assumptions were used  in
 the derivation.  Additional site specific evaluations of potential
 dose rates to lung and bone (Section 4) should be made before remedial
 actions are initiated.
                                    20 2

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      Inherent in the application of the screening  level  is  the
 assumption that soil contamination by the transuranium elements will
 cause radiation exposure through pathways such as  the inhalation of
 resuspended soil, the ingestion of foodstuffs grown on the  soil-, the
 ingestion of soil by children, and the ingestion of drinking water
 contaminated by soil runoff.  In all cases the cumulative doses to the
 critical segment of the population must be considered, with the
 admonition that the accumulated doses from all pathways  should not
 exceed those recommended in this Guidance.                         "

 5.4  Implementation of Guidance by Means of Soil Data Using
      Site-Specific Parameters

      Federal agencies may show compliance with this guidance for a
 specific site,  or for subareas of a specific site, by means of soil
 measurements and by using pathway and dosimetry models with parameters
 determined for  the specific site to certify that the resulting dose
 rates do not exceed Guidance values.   This approach differs from the
 use of a soil "screening level" because parameters such as the
 resuspension factor are determined for a specific site.   It is
 expected that use of site-specific parameters will show that soil
 contamination levels higher than the  suggested "screening level" may
 correspond to organ doses well below  Guidance levels.   Implementation
 by  site-specific parameters is appropriate where land  areas have
 transuranium element levels greater than the "screening level" and
 further evaluation is  necessary to determine whether or  not guidance
 dose limits  are  being  exceeded.

      The  air concentration  where  people  are  located generally  can be
 correlated with  the  adjacent soil  concentration  by use of a
 resuspension factor, and can be  used  to  estimate  the inhalation dose
 rate.   The site-specific resuspension  factor may  be either measured
 directly  or  calculated  from other  data.   Direct  experimental
 determinations are often difficult  to make and not always
 reproducible.  Therefore, calculational  techniques are sometimes
 preferred although their correlation with  measured values is subject
 to  considerable  uncertainty.   The  agency  staff has developed a method,
 based  on  the  concept of  air mass  loading,  which may be useful  for  this
 purpose(see Annex II).   An  "effective" resuspension factor is  derived,
 defined as the resuspension factor  derived from  the air mass loading
 for  the given location and  modified by a "distribution factor"  which
 takes  into account the generally observed  nonuniform distribution of
 the  activity with size of particles in calculating the amount  of
 transuranium element activity  in the inhalable fraction of the
 resuspended material.  The  "distribution factor"  is  a  theoretically
 derived parameter, and its  correlation to  actually  observed  situations
has  not yet been established.  The  resuspension factor derived  in this
manner  is applicable only to extremely large  areas  sources,  and must
be further corrected for the dilution by uncontaminated materials when
used for  small contaminated  areas.

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     The ingestion pathway must be evaluated separately, using data
applicable to the specific site in terms of type of crops, plant
uptake parameters, and pathway to a critical segment of the
population.  The more unusual transfer mechanisms to people, such as
the ingestion of dirt by children and the contamination of drinking
water sources, may also need to be examined if shown to be of
importance.

5.5  Sampling and Analysis Methods

     Choice of Methods

     The choice of suitable methods for  sampling and analysis  is the
reponsibility of the Agency implementing the Guidance.  The
implementing Agency should demonstrate  that the proposed methods have
the necessary sensitivity, accuracy,  and precision.  A  description of
the apparatus and techniques used to  collect the samples,  the
procedures for preparing the samples  for analysis,  and  the method used
for radiochemical analysis should be  included.

     Air Sampling

     When  air sampling  is  chosen as the principal method  of
implementing  the  guidance, continuous monitoring should be performed
at  locations  indicative of potential  doses  to  persons  in  the  general
population.  Aerosol  collection efficiencies as a  function of particle
size  and  other  appropriate parameters must  be  reported  for the
instruments  and  placements used.  Results must be  given in terms  of  an
annual  average  air  concentration  of  transuranium  elements at  the
specified  site.

      Food Sampling

      When foods are grown  in contaminated  soils,  and the  ingestion
pathway may represent a hazard to persons  in a critical segment of the
population,  representative samples  should be obtained for analysis and
 evaluation.   Results should  be reported in terms  of activity  per  unit
 of wet or dry weight, as appropriate, for specific food products  and
 for typical "market basket"  averages for an individual.

      Drinking Water Sampling

      When soil or sediment analyses indicate the potential for the
 presence of transuranium element contamination in drinking water
 supplies, periodic monitoring should be performed.  Results should be
 reported in terms of activity per unit volume for both raw and
 finished drinking water.
                                     204

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     Soil Sampling

     When soil sampling is chosen as either the principal or  ancillary
method of implementing the Guidance, statistically valid procedures
appropriate to the objective should'be used to characterize the entire
area known or suspected to be contaminated.  When soil measurements
are made to evaluate the inhalation pathway, emphasis should  be on
obtaining representative samples of surface soils subject to
resuspension and transport.  In order to achieve a degree of
uniformity in application, the Agency recommends that soil samples be
taken to a depth of one centimeter and include all soil particles less
than, two millimeters.in size.  Several individual samples may be
composited for a single measurement.  At some sampling points it may
not be possible to collect samples to a depth of one centimeter e.g.,
very stony soil or a thick grassy area).  In such cases, other means
must be found tor obtain representative samples.

     For site-specific evaluations of resuspension parameters, it may
be necessary to determine the fraction of the total activity
associated with ranges of soil particle sizes (distribution factor).
Standard liquid or air sedimentation and separation techniques may be
used for this purpose.  In general, soil characteristics should be
altered as little as possible in' the collection and preparation of the
soil sample and care should be taken to choose a method which does' not
cause the breaking up of soil aggregates that were present when the
sample was taken.

     Radiochemical analysis techniques for the determination  of ,
transuranium elements in soils are available and have been published.
These differ primarily in the method used to solubilize the plutonium
in the sample.  Acid leaching, acid dissolution, and fusion are most
commonly used.  The fusion method is considered to be applicable to a
wider variety of soils than the other two methods.

     Alternative collection, separation, and analysis methods may be
used but must be adequately justified in terms of technical validity
and relationship of results obtained by the recommended method..

     Statistical Criteria

     The characterization of any large area in a cost-effective manner
requires that the sample locations be carefully determined in order to
optimize the information obtained.  Statistical methods are available
to permit design of experiments to obtain results with the accuracy
and precision desired.  ••'.,-                                       ,

     When planning a soil survey it is advisable to divide the total
area under investigation into units at the very begining of the survey
rather than to collect samples more or less haphazardly.  Then samples
                                  205

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taken to determine the acceptability of the land by.comparison of
measured concentration levels to the screening level may be  collected
from sampling units in accordance with a sampling plan.  If  it is
later decided that more sampling is necessary, no change in  the
sampling plan is necessary, and the location for additional  samples
will have already been determined.

     The number of samples to take within a sampling unit may be
estimated from the specific statistical approach used  in the sampling
plan.  An important factor affecting the number of samples to be taken
is the risk of making the wrong decision in deciding whether a
sampling unit is acceptable or requires remedial action.  To reduce
the risk of making the wrong desision, larger numbers  of samples must
be taken.  Judgment must be used to strike a balance between the
desirability of making the right decision and the difficulties and
expense involved in taking large numbers of samples.   An additional
factor affecting the number of samples is the variability of the
transuranium element concentration within a sampling unit.   If
detailed information is not available on the variability, a  simple
approach is to take the same number of samples within  each unit.
These could be taken on a grid system to ensure that all subareas of
the sampling unit are sampled.  A disadvantage of this approach  is
that if the variability is substanially different in units,  then the
probability of detecting concentration levels requiring remedial
action will vary from unit to unit.  If estimates of variability are
available from past studies, these can be used to help determine the
number of samples required within each unit so that the probability of
making a correct decision will be the same for all units.

     After soil concentration levels have been determined, it must be
decided if the area under consideration complies with  the Guidance
recommendations or whether further evaluation will be  needed.  The
statistical methodology that is used must be such that few assumptions
regarding the form of the soil concentration distribution will be
necessary to ensure the validity of the statistical test.  The method
should also ensure reasonably low bounds on the risk of making  the
wrong decision, arid the probability of not accepting an area which
meets the guidance, or accepting one which does not, should  be  small.
Acceptance criteria which allow a maximum chance of error of 5-10% are
generally considered appropriate.

     Considerable variation  generally occurs  in environmental  samples
taken even in closely adjacent locations.  If one or more  samples  from
any unit exceed the air or  soil concentration limits corresponding  to
the guidance recommendations, a decision must be made  on whether the
sampling unit is acceptable.  Such decision is best based  on
statistical  tests which consider both the magnitude of the  deviations
from the average and the number of samples which are involved.   A
number of statistical methods are available for performing  such  an
evaluation,  and the choice must be made on the basis of the  data
available and the  results desired.

                                    S06

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             6. THE DOSE AND RISK TO HEALTH DUE  TO  THE
           INHALATION AND INGESTION OF TRANSURANIUM HUCLIDES

6.1  Revised Risk Estimates For Leukemia

     Due to a  computational error, the leukemia  risk  estimates
published in Annex III of ths proposed guides  (Pr 77) are  too low.
While this has little effect on the estimated  total risk due to  the
inhalation of  Class Y materials, it does affect  the estimated lifetime
risk due to ingestion, as well as estimated risk due  to the inhalation
of class W materials described in section 6.3  below.

     Amended risk, estimates are given in Table 6.1.1.  As  before, all
risks ara based on lifetime exposure to 100,000  persons at the
proposed guidance limits: for inhalation, 1 mrad per  year  to pulmonary
tissue and for ingestion, 3 mrad per year to bone tissue in the  70th
year.
                              TABLE 6.1.1

       New Leukemia Risks for Lifetime Exposure to Plutonium-239
     Estimated Risk
     Leukemia
     New total Ca risk
     Total risk estimated in Annex III

         • Table A3-18
 Cancer Deaths per 100,000 Exposed
Inhalation - Class Y      Ingestion
        1.2                   9
       10                    1H
        9*                    5.6
     The table above is based on a quality factor of 20 for alpha
particle irradiation, as stated in the guidance document.  This choice
is based on ICRP Report No. 26, referenced in Annex III.  More recent
information on the leukemia experience of Japanese atomic bomb
survivors than was available when Annex III was prepared, indicates
that a quality factor of twenty is not unduly conservative for
purposes of estimating risk of leukemia from high LET radiations.
Risk estimates based on the tissue dose rather than kerma exposure to
the Japanese survivors are discussed in Section 6.2 below.

6.2  Estimates of Leukemia Risk Based on Tissue Dose

     The leukemia risks for high LET radiation, mainly proton recoils,
in the 1972 BEIR Report are based on "tissue kerma in air1*, i.e.,
attenuation of the dose by tissues overlying the bone marrow was
neglected.  Recently, T. Ishimaru, M. Otake, and M. Ichiraaru have
reviewed the dose response pattern for the Japanese survivors in terms
                                  207-

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of the calculated dose to bone marrow (Is 77).  This was made possible
by detailed information on the gamma ray and neutron doses to bone
marrow developed by the Oak Ridge National Laboratory subsequent to
the BEIR Report (Jo 76).  These results indicate that the proton dose
to marrow was only 26 percent of the tissue kerma in air, an
appreciable difference.  Moreover, use of tissue dose for high LET
particles allows leukemia risks to be estimated directly (i.e., per
unit rad), rather than by means of an arbitrary quality factor based
on a number of end points.  Except for leukemia, direct calculations
of risk per rad were used throughout Annex III to calculate somatic
risk.  Therefore, use of such a direct approach should make the
estimates of leukemia risk more comparable to that  for other cancers.
It should be noted that the linear energy transfer  (LET) for 5 MeV
alpha particles from the decay of transuranium nuclides is nearly the
same as for one MeV recoil protons.

     In their review of risk to Japanese survivors, Ishimaru et al.
fitted various dose responsive functions to the leukemia incidence
data to account for both the gamma-ray and neutron  dose.  For  the
gamma-ray dose, linear, parabolic, and quadratic responses were
examined in combination with a linear response  for  the high LET recoil
dose.  Use of these various models resulted in  little difference in
the calculated risk for neutrons, 23-28 cases per million rad  person
years at risk.  Although there is no  statistically  significant
difference between  these two estimates, the former  number,  based on  a
linear response for both neutron  and  gamma  radiation,  is utilized
below.

     Unlike the 1972  BEIR  Report,  the results  cited above  on the
leukemia risk  due to  neutrons  does  not  consider children of less  than
ten years  of  age  as a separate  population at  risk.   Rather,  the
analysis  is based on  all ages.   This  should not be a serious source  of
bias  since  the proportions of persons under ten among the  Japanese
survivors  is  not  too  different  from that  in a stationary population.
Moreover,  exposures during childhood  contribute only two to ten
percent  of the total  number of excess leukemia cases resulting from
lifetime exposures to transuranics.

      Input parameters for the leukemia risk estimates are listed in
Table 6.2.1,  the selection of plateau period and duration of the
 latent period are based on the 1972 BEIR Report (Na 72).   The relative
 risk coefficient is based on the regression results for bone marrow
 neutron dose given for Model I by Ishimaru et al^, (Is 77).
                                    208

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                              Table 6.2.1

                 Parameters for Leukemia Risk Estimates
                 High LET Particle Dose to Bone Marrow
Latent Period
  (Years)
Plateau Period
  (Years)
                       25
Absolute Risk
Death per
     RPY*

      23
  Relative Risk
% increase in
  deaths per rad

        70$
     *Rad x person years at risk
                           - '              ••               .           i
     Table 6.2.2 compares the average of relative and absolute risk
estimates made with these parameters to those listed in Table 6.1 for
plutonium-239 ingestion.
                              Table 6.2.2

                  Leukemia Risk for Lifetime Exposure
                Per 100,000 Persons - Bone Tissue Limit
                    3 mrem Per Year in the 70th Year
             Basis for Calculation

         Quality factor of 20, Table 6.1.1
         Japanese Survivors, Table 6.2.1
                             Estimated Deaths
6.3   Dose Rates and Estimated Risks Due to Inhaled Class W Compounds

6.3.1 Introduction

     The ICRP Task Group Lung Model (Ta 66, In 72) classifies inhaled
aerosols into three groups depending on the length of time they are
retained in the lung.  Class Y compounds are retained for years, Class
W for weeks, and Class D for days.  The retention times are largely
controlled by the solubility of the inhaled material in body fluids.
In the * technical document (Annex III) for the proposed guidance
(Pr 77), it was assumed that respirable materials which persisted in
the environment would most likely be insoluble oxides-and hydroxides
and therefore be Class Y materials.  However, there is some evidence
from animal experiments that high specific activity plutonium oxides
such as 238puc-2 are more soluble than the long half life
transuranics and should be considered Class W compounds.  Moreover»
other transuranics, such as americium-24l and curium-244 may in some
cases be in a chemical form that leads to Class W behavior.  The
purpose of this section is to examine the dose due to. the inhalation
                                  209

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of Class W transuranium aerosols and the estimated risks from such
exposures.  It should be noted that solubility as a function of size is
not considered by the ICRP Task Group Lung Model.  In practice, higher
solubility for sub-micron aerosols is likely to occur; therefore, the
estimated risk due to compounds more soluble than Class Y materials is
also of interest for this reason.
6.3.2 Application of the Proposed Guidance to Class W Transuranium
      Compounds
     The proposed guidance places two limitations on the alpha particle
dose rate to exposed persons:  a maximum dose rate of 1 mrad per year;
to pulmonary lung tissues and a maximum dose rate of 3 mrad per year to
bone tissue after a 70-year (lifetime) exposure.  In both cases the
alpha energy is averaged over the total tissue mass (Pr 77).  Because
of their shorter residence time in lung tissues, inhaled Class W
transuranics result in a relatively small lung dose compared to that
received by other organs due to the translocation and deposition of
dissolved material.  Therefore, the dose rate to bone tissue becomes
limiting, not the dose rate to pulmonary lung.

     Table 6.3.1 lists the air concentrations of Class W transuranium
radionuclides that result in an average bone alpha dose of 3 mrad per
year after 70 years of exposure.  The potential risks due to inhalation
of Class W transuranics are not confined to bone cancer but include
leukemia and cancer of the liver and lung as well as genetic effects,
see Section 6.3-4 below.
                              TABLE 6.3.1
                       i
         Aerosol Concentrations 'in fCi/m3 Producing a 3 mrad
     Annual Skeletal Dose Rate in the 70th Year Following Lifetime
            Inhalation by Reference Man - Class W Solubility
Size
(AMAD)
0.05
0.10
0.30
0.50
1.0
2.0
3.0
5.0
238Pu
94
5.7
6.4
7.6
7.8
7.8
7.2
6.7
6.4
239Pu
94
4.8
5.3
6.3
6.5
6.5
6.0
5.6
5.4
24lPu«
94
200
220
260
270
270
250
240
230
95
4.7
5.3
6.3
6.4
6.4
6.0
5.5
5.3
244Cm
96
11
12
14
15
15
14
13
12
•Only alpha dose rate due  to  the Am-241  daughter  is  considered  in
assessing limit
                                 210

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     For most transuranic materials (the exception is Plutonium-241)
the limiting concentration in air of a Class W material is greater than
that, for a Class Y material containing the-same radionuclide.-
This difference is as much as a factor of five or more for the smallest
particle sizes, considered in Table 6.3.1,  c.f. Table 6.3.1 with Table
A-3-4 in Annex 111(3).  For 1 micron AMAD particles the limiting
concentration of Class W compounds is about 3 times greater  than for Y
compounds.,;  For this reason, there must be reasonable assurance jthat
the inhaled material is in the form of a Class W compound before" Table
6.3.1 is used to establish compliance with the proposed guides.  When a
mixture of Class Y and W compounds are inhaled, compliance should be
based on the limiting concentration for Class Y materials unless the
proportion of each type of pollutant has. been fully established.
Plutonium-241 is an obvious exception since the limiting concentration
is up to 8 times less for a Class W than for a Class Y material.

6.3.3 Alpha Particle Dose Rates from Inhaled W Aerosols .

     The annual dose rates following 70 years of inhalation  exposure to
several transuranium radionuclides in the W form are listed  in Table
6.3-2 for 1 micron (AMAD) particles.  More than 99 percent of the
equilibrium dose rate to pulmonary lung tissue is achieved after five
years of exposure.  For other organs the dose rate increases with the
duration of exposure. It is recognized that lifetime .exposure to a
constant concentration of curium-244 aerosols is unlikely because of ,
its relatively short half life (17 years).

                              TABLE 6.3.2

     Annual Dose Rates to Various Organs of Reference-Man Following
       Chronic Lifetime Exposure to Class W Transuranium Aerosols
        Concentration 1 fCi/m3; Particle Size 1 micron (AMAD)


Equilb. Dose

Radionuclide Pulmonary
-
Pu-238
Pu-239
Pu-241
Am-24l
Cm-244
Lung
41
39
0.04
41
44
Rate (microrad/y)

Tracheobronohial
Lung
16
15
0.01
15
17
Dose rate in the
70th yr (microrad/y)

Bone Liver

390 810
460 930
10 20
470 960
200 460

Bone Marrow

340
400
9
410
180
     Effective biological half lives  and removal  pathways  for  lung
deposited Class W compounds are  described  quantitatively in  (Su  77),
along with the description of the analytical  techniques  used in  the
                                   211

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preparation of Table 6.3.2.  As was the case for Class Y materials,
eight particle sizes (AMAD) were considered in these calculations.  The
variation of dose rate with particle size of Class W particles is shown
in Table 6.3-3.  Unlike the case of Class Y particles, a broad minimum
dose rate to liver and bone is observed for aerosols of between 0.3 and
1 micron (AMAD).  The variation in pulmonary dose with particle size is
the same as for Class Y compounds.
                              TABLE 6.3-3

            Variation with Particle Size of the Dose Rate to
      Pulmonary Lung, Bone and Liver for Inhaled Class W Aerosols
           (Lifetime Inhalation at a Constant Concentration)
Particle Size
AMAD (Microns)
     0.05
     0.10
     0.30
     0.50
     1,
     2,
     3.
     5,
00
00
00
00
                    Equilibrium Lung
                    Dose Rate Ratios*
2.6
2.2
1.6
1.4
1.0
0.7
0.6
0.5
                     Dose Rate Ratios*
                    for Bone and Liver
                     in the 70th Year
                                                        1.1
                                                        1.2
                                                         .0
                                                         .0
1.
1.
1.0
1.1
1.2
1.2
•Normalized to 1 micron (AMAD)
6.3-^ Health Risk Estimates for Class W Transuranios

     The inhalation of Class W compounds results in both somatic and
genetic risks.  Although the limiting dose rate for inhaled Class W
compounds is in terms of the dose to bone, the dose to lung tissue is
not negligible.  The estimated risk of lung cancer is about the same as
the estimated risk of leukemia, liver or bone cancer.  The genetic risk
for inhaled Class W transuranium materials is larger than for inhaled
Class Y aerosols, being nearly the same as the genetic risk for
ingestion listed in Annex III (Pr 77).

     The methodology for estimating somatic and genetic risks due to
the inhalation of transuranics is discussed in Annex III (Pr 77).  Like
the case for transuranium ingestion, where the dose rate limitation for
bone tissue is also 3 mrad per year, the 30-year gonadal dose for most
inhaled Class W transuranium compounds is about 10-12 mrad, i.e.,
calculations of 30-year gonadal dose for Class W yielded results
identical to those listed in Table A3-15 of Annex III (Pr 77).
                                   212

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Therefore, the estimated genetic risks for Class W inhalation are  the
same as listed in Table A3-16 (Pr 77) for the ingestion pathway.

     Estimated somatic (cancer) risk following inhalation of Class W
are listed in Table 6.3.4 below.  The assumptions made in the
calculations of these risk estimates are the same as made for Y
compounds in Annex III except that, a quality factor of 20 was used for
leukemogenesis.


                              TABLE 6.3.1*

   Estimated Risk of Cancer Due to a Lifetime Inhalation Pattern That
    Results in a 3Mrad Per Year Alpha Particle Dose Rate to Bone  in
          the 70th Year - Number of Deaths per 100,000 Persons

                            Class W Aerosols
     Cause of Early Death
     Lung cancer
     Bone Cancer
     Liver Cancer
     Leukemia
                    TOTAL,
 Pu-238

b  2.6
  2.6
  2.2
  9.2
   17
      Radionuclide
Pu-239   Pu-241
 2.1
 2.U
 1.9
 8.8
  15
0.11
 11
 6.i»   Transfer  of Transuranium Material to Blood From the GI Tract,

      In  the  course of reviewing the literature on. transuranium elements
 while preparing "Proposed Guidance on Dose Limits for Persons Exposed
 to Transuranium Elements in the General Environment'1, the staff was
 concfpned about using truly appropriate gut transfer factors for the
 transuraniuin isotopes.  While ICRP Report f19 recommends a gut transfer
 factor pf 1  part per 10^ for "relatively insoluble material, such as
 PuQ2nt transfer fractions of the order of 10~2 to 10"* are not
 unCQpimon in  more cpntempoj-ary reports (S\t 75, Su76, Pi 76, Br 75).  In
 view of  these reports of higher gut transfer"factors, the staff took
 advantage ol an ERDA offer of aid from their contract laboratories.
 Th§  letter containing EPA proposed gut transfer factors circulated to
 ERDA investigators considered knowledgeable in this field is reproduced
 below.

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                             13  DEC 1376
 Dr. William J. Eair
 Director,  Life Sciences Program
 Pacific Northwest Laboratories
 Battello Memorial Institute
 Rlchland,  Washington

 Dear Billt

     In the hope of trying to reach accord with ERDA on the doalnetrlc
 parameters used by. EPA in developing guidance for plutoniun In soils,  we
 «r« asking several ERDA investigators for relevant consents*

 .    Heal  Kelson has prepared a table of provisional gut transfer frac-
 tions for  transuranic isotopes, enclosed.  The data is derived prlnarily
 from ERDA's BSHL presentation at the EPA hearings in Washington (WASH-
 1539) and  from the 1975 BHKL Annual Report, BSWL-200C-PTI (Sullivan  and
 Crosby).   Since theaa reports reflect, for the roost part, observations
 On rate, some consideration was also given to Battelle data on swine
 CBNHL-280) and Suldakov, et al.'e data on dogs.*

     Tour connenta on whether these gut transfer factors seera  reasonable
 Or not, and any codifications you would suggest, based on your own
 Interpretation of the Battelle or other data,  would be appreciated.
•L. A. Buldalcbv,  B. R. Lyubchanokii, Yu. I. Koskalev and A. P. Hitatov,
 Frobletua of Plutonium Toxicology, LF-tr-41, 1970.
                            •214

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                                 2
     Zf possible, we vould like your eonments before Christmaa as
Vd ftrs trying to complete a new draft, not a redraft, on doee and effects.
Siffica the nails are bad, perhaps you would phone Neal or me (202-755-3852)
after you have reflected OB the proposed numbers.

                         Slaeerely yours.
                         W. E. Ellett, Ph.D.
                         Chief, Bioeffects Analysis Branch
                         Criteria & Standards Division (AN-460)
                         Office of Radiation Programs
    .osura
      e Chester Riehnond, Oak Ridge Rational Laboratory
    Dre Roy Thompson, Battelle Northwest Laboratory
    Ite, John Marshall, Argoane National Laboratory
 AH-460/NSNelson/mlb  12/10/76  WSMIE; 629,  ext 5,3852

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                       Provisional Gut Transfer Fractions
                           . for Transuranic Elements
Isotope
Np+5 soluble
     oxide
biologically incorporated

238Pu*4 soluble
     oxide
biologically incorporated

239Pu*4 soluble
     oxide
biologically incorporated

Am   soluble
     oxide
biologically incorporated

Cm*3 soluble
     oxide
biologically incorporated
Bk, Cf, Es soluble
     oxide
biologically incorporated
Infant (0-1 yr)
7 x 10
      ,-2
2 x 10"
5 x 10
      ,-4
4 x 10
2 x 10
f3
,-4
9 x 10
      ,-2
5 x 10
      ,-3
6 x 10
10"

4 x 10
      ,-2
      ,-2
                Child  (>  1-9 yr)
                 10
                  ,-2
                      10
                        ,-3
                      3 x 10
                      2 x 10"
                      3 x 10"

                      2 x 10"
                            ,-4
                        ,-6
                 10
                5 x  10"
                      10


                      10
                      10
                  ,-4
                  ,-3
                      5 x 10
                      ,-4
                                             Adult (> 10 yr)
                                             10
                                              ,-2
                                        r3
                                       10
3 x 10'
2 x 10
3 x 10
                                             r4
                                             ,-3
2 x 10
lO'6


5 x 10"
1C'4


10"3
10~4

5 x 10
                                                   ,-4
                                                  ,-4
[Estimates based on Battelle rat and pig data and Russian dog data.]

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     Scientists at Battelle Pacific Northwest Laboratories considered
the question in some detail and simplified the age specific table of
gut transfer factors proposed in the EPA letter.  Their response is
reprinted below.  It acknowledges both the uncertainty and conservatism
in these estimates, a conservatism necessitated by the extrapolations
from animals to man.

     The EPA staff used the estimates provided by BPNL scientists as
prudent values for protection of public health in their development of
the Guidance for Transuranium Elements.

     Responses from other ERDA investigators were of a non-numerical
character and not directly applicable to the problem.
                                    217

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 February 1, 1977
                                                       IIBalielle
                                                            l.uilK  Noii|i,v(>sl l.ihni.ilniir
                                                             ll.lllcllf Hoillcv.iirl

                                                             K» M m«l, W.iOiutfM
                                                                       946-2421
                                                                ».' «. tr.
 Dr.  W.  H.  Ellett
 Dr.  N.  S.  Nelson                                           '
 Criteria and  Standards  Division - ORP
 Environmental  Protection Agency
 Waterside  Mall  - 629E
 4th  & M Streets  SW
 Washington, D.C.   20460                                                            :

 Dear Bill  and  Neal:

 We have had extensive discussions with several scientists in the Biology and
 Ecosystems Departments concerning your need for gut transfer numbers.   As you are
 well aware, this is an area of current active investigation and everyone would
 rather  have a  few more years to get better answers.  But we recognize  your
 problem and will attempt in this letter to give our best advice,'emphasizing that
 it is an interim appraisal, almost certainly erring on the conservative side, and,
 of course, subject to future revision.

 We will make no attempt in this letter to review the data.   You are as aware of
 most of this data as  we are—as evidenced by the extensive compilation of numbers
 enclosed in your recent letter.  One of our objectives has  been to  reduce the
 complexity of that table,  since we feel  that it implies a great deal more confidence
 in small differences- than  we are entitled to have.   We are  all  aware of the  many
 uncertainties involved in  the measurement of these .numbers  and  in their extraoolation
from animals to man.

The numbers we would  recommend for all  transuranics  are the following,  expressed
as fraction absorbed  to blood:                                    •
     Child and Adult (>_ 1 year):   10

                     -4
          except:   10 n for

     Infant (< 1 year):   10" ]
                     -4     23Q              "?
          except:  10 n for  03Pu02,  5 x 10   for biologically incorporated  transur
          except:  10
                     -2
                        for 239PuO,
This amounts to choosing a single basic value of 10  ,  to which  v/e  make  3 exceptions
a factor of 10 decrease for 239pUQ2,  a factor of 5 increase  for  biological  incorpor-
ation, and a factor of 100 increase for the infant to age 1  year.

Our basic factor of 10~  is conservative,  but this seems  justified  in view  of the
uncertainty involved in extrapolation to the human.   It is undoubtedly more
conservative for plutonium than  for the transplutonium  elements, and not conservative
for neptunium, but this seems  reasonable in view of  the relative significance of
these various elements as  possible environmental  contaminants.
                                     218

-------
Drs. W. H.  Ellet.t. and
N. S. Helsorv
      February 2,  1977
                                                                     239,
Because of the abundance of data showing a much lower absorption for    Pu02,
and because of the importance of this compound, an exception seemed justified.
A fiqure of 1(TS might well be justified from animal  data, but again^we felt
that in view of the uncertainties in extrapolation to man, conservatism was
in order.

The factor of 5 for biological incorporation is based on very limited, and not
always consistent, results .from experiments in progress, in which rats and guinea,
pigs were fed alfalfa that contained biologically incorporated plutom,um.  We
may have a better basis for this number within a few months.

Without doubt the greatest uncertainty attaches to the number chosen for the
infant, and to the time period assigned to infancy.  The factor of 100 seems to
be a maximum enhancement factor, based on the data ava Table.  There is; Decrease
in this enhanced absorption with age, but no clear basis-far^extrapolating this
decrease  to man.  Depending on your.assumed theory for :explaimng^the enhanced.
absorption you can argue for a period of a few days, or for a^much longer period-
We feel that assumina a high enhancement value of 100, without decrease over the
first year .of,life,  Is  a .conservative approach.  Rather than  i.sting an absorption
factor of10-1, for  which  the evidence  is so indirect, we would prefer to use.-the ..
adult factor in all  calculations and then apply a lifetime "correction factor  of
2  to account for possibly  enhanced absorption during infancy, thus stating no
specific  increase and no specific period  during which  it  applies.

We-have,  applied the  factor of 10 reduction for 239Pu02 to the infant  because of
the  substantial amount  of  data  showing  that transuranic oxides  are  less well
absorbed  by very young  animals  than, are ol-her  compound forms.

We have  not applied  the biological  incorporation  factor to the  infant, primarily
because  it would  involve multiplying three, conservatively chose,n  numbers, to arrive
at a  prediction of  50%  absorption, which seems quite unreasonable.   On more     .
 scientific  grounds,  one can  argue that  the mechanisms  for enhanced absorption_due
 to infancy  and  due  to  biological incorporation are_most likely  totally unrelated
 and  therefore  not multiplicative in their application.
 We hope that this effort has been helpful.   There are no easy answers.
 keep you informed of any new developments  in our research in this  area;
 be glad to respond to any further questions that you might have.
 Sine
                  We will
                  and would
 W. d. Bair, Ph.D.
 Manager  >
 Environmental & Safety
 .  Research Program

 RCT:WJB:ms
R. C. Thompson, Ph.D.
Senior Staff Scientist
Biology Department
                                            T O

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 In  72
Is 77
Jo 76
Pr 77
Su 77
Ta 66
                       REFERENCES

 International  Commission  on  Radiological  Protection Publication
 19,  1972.   The Metabolism of Compounds  of Plutonium and Other
 Actinides.  Pergamon  Press, New  York.~~

 Ishimaru, T.,  M. Otake and M. Ichimaru, Incidence of Leukemia
 Among Atomic Bomb Survivors  in  Relation to Neutron and Gamma
 Dose, Hiroshima and  Nagasaki 1950-71, RERF Technical Report
 Series, TR  14-77, Sept. 15,  1977.  Printed March 1978.

 Jones, T.D., Radiation Insult to the Active Bone Marrow as
 Predicted by a Method  of  CHORDS, ORNL Report ORNL/TM-5337,
 1976.

 Proposed Guidance on Dose Limits for Persons Exposed to
 Transuranium Elements  in  the General Environment, 1977.
 EPA 520/4-77-016, U.S. Environmental Protection Agency,
 Washington, D.C. 1976.

 Sullivan, R.,  1977.  Plutonium Air Inhalation Dose (PAID).
 ORP/CSD Technical Note 77-4,  U.S.  Environmental Protection
Agency, Washington, D.C.   20460.

Task Group on Lung Dynamics  (TGLD) 1966.  Deposition and
Retention Models for Internal Dosimetry of the Human
Respiratory Tract,  Health Physics  12:173-208.
                                220

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7.   Rocky Flats Facility/Technical Assessment Document









7.1. Introduction



     The purpose of this report is to present an analysis of the potential




hazards to individuals in the general population as a result of present




levels of the transuranium elements existing in the environs of the DOE




.,Rocky Flats Plant.  The various pathways by which exposures might occur




under present and projected land usages are examined and interpreted in




light of EPA's  proposed guidelines for exposures to the transuranium




elements.








 7.2  Inhalation Pathway








 7.2.1      Ambient Air Concentrations



     Under normal operating conditions, minute quantities  of plutonium




 and other radionuclides  are released  per  year to  the  atmosphere from the




 Rocky Flats Plant.   These releases are of small magnitude  and  originate




 from the plant's ventilation and filtration system.   In addition to




 continuously monitoring the effluent  air  from production and research,




 facilities, the Rocky Flats facility maintains a system of high-volume




 ambient air samplers within the plant boundary, at off-site locations in




 the immediate vicinity of the plant,  and in several nearby communities.




 Altogether the system comprises 21 air samplers operating continuously




 within and on  the perimeter of the Rocky Flats security area,  and another




 25 samplers located  at various distances and directions from the plant.




 The data from  this network are reported on a monthly basis to the Rocky




 Flats Area Office of DOE, the Division of Occupational and Radiological
                                  221

-------
  Health of the Colorado Department of Health,  the Denver Regional Office


  of the EPA,  the Health Departments of Boulder and Jefferson Counties,


  and city officials in several communities near the plant.


       In addition to the surveillance network  maintained by  the Rocky


  Flats Plant,  the Health and  Safety Laboratory (HASL) of DOE has  con-


  ducted a program of continuous air sampling for  plutonium at the Plant


  since June 1970  in response  to the discovery  of  elevated levels of


  plutonium found  in soils at  location which were  then off-site.  The HASL


 network  consists  of  four sampling  locations (Figure 7.1), three 6f which


 are downwind  (east)  from the original location of the oil drum storage


 site and the fourth air sampler is located off-site and upwind from the


 Rocky Flats Plant  (2).  Air concentration data in attocuries of Pu-239


 per cubic meter of air (aCi/m3)*, as reported by this network on a


 monthly basis from June 1970 to March 1976, are given in Table 7.1.  A


 significant downward trend with time can be seen in the level of  plutonium


 in air at the stations downwind from the plant.   It has been suggested


 by HASL that  this downward trend  is attributable to the weathering of


 the contaminated soil in the  on-site vicinity  of the original oil drum


 storage site.   This weathering may be due to the movement of the  plu-


 tonium from the surface down  into  the soil, as well  as  changes in the


 characteristics of the plutonium remaining on  the surface.   In addition


 to  showing a decrease with  time, the  data indicate a decrease in con-


 centration with increasing  distance downwind from the site of the


original  spill  area.   Based upon air and  soil sampling, as well as the


direction of the prevailing winds around Rocky Flats, HASL concluded in

1972 (3)
 *1 attocurie = 10~  curie
                                  eynr
                                      '

-------
ro

            RT.72
                  ;.'•  \
                                          I PLANT SITE
                                                    »  EAST GATE
                                           SPILL AREA
                                                               V
                                                                Vs
                                                                         T. WESTERN

                                                                          RESERVOIR
t=t
                                                                        MILES
                 MAP OF ROCKY FLATS PLANT AND VICINITY

             INDICATING CONTINUOUS AIR SAMPLING SITES

                                      FIGURE 7.1
                 ;3
                 «

-------
 that the original spill area was the primary source of plutonium in the


 Rocky Flats environment.



      Levels of airborne plutonium at the downwind edge of the facility's



 buffer zone (Indiana Street) are approximately the same as reported for



 the monitoring station upwind from the plant.   Although these levels are



 about twice those expected from background radioactivity in the  Rocky



 Flats area,  the effect of the spill area upon  the off-site environment


 has been much reduced from earlier levels.



      Comparison of the most recent HASL data (1976)  for the Indiana



 Street location (site 2)  with the 1975 data reported by the Rocky Flats



 Plant (Table 7.2)  for the same' general area shows the  two networks  to



 agree within a factor of  about 2.   The values  reported by HASL range


                      '3
 between 12  to 23  aCi/m ,  while Rocky Flats  reported  an average of 37


 aCi/m3.



 7.2.2    Calculation  of  Inhalation Doses Due to  On-Site Contamination
     An assessment has been made of the potential inhalation dose which



could be received by individuals residing off-site of the Rocky Flats



Plant.  In carrying out this assessment, a deliberate effort has been



made to choose assumptions which are conservative, i.e., likely to



result in an overestimate of the actual dose. These are:



     a)   Inhaled plutonium is considered to be in an insoluble form.



(Chemical solubility of an aerosol determines its residence time in the



lung, with insoluble compounds being retained the longest.)
                                 £a (rt \ti

-------
      b)  The plutonium aerosol is assumed to have a lognormal distribution

with an activity.median aerodynamic diameter (AMAD) of 1 micrometer.

(According to the ICRP (4) this implies that approximately 25% of the

aerosol will be deposited in the pulmonary compartment of the lung.

HASL ,.(5)i has reported 25% of the airborne activity being in the respirable

range- around Rocky Flats, while Sehmel  (6) has reported a 20% respirable

fraction)..    '                     ...        .

      c)  The individual is considered to be- exposed continuously  for  70

years at the  currently observed air  concentration.   (No further reduction

in airborne activity as a result  of  weathering  or remedial actions  is

assumed.)

      d) All  plutonium measured was  assumed to  originate  from on-site,

with no correction being  made for ambient  background levels  of plutonium.

      The PAID code developed,by EPA (7) was used to-calculate the annual

 dose rate.  This computer code is based upon the ICRP Task Group  Lung

 Model  (4)  and calculates  dose rates to various  body organs as a consequence

 of inhaling transuranic material.   Tables 7.3 and 7.4 have been generated

 by the PAID code and relate years of exposure to the resultant dose rate

 for various, organs. Values in the tables are normalized to an aerosol
                                                              3
 concentration of 1.0 femtocurie per cubic meter of air (fCi/m )* with a

 1 ym AMAD.                                       •

      Indiana Street Location

      Indiana Street  is the nearest  location.tp.the ,Rocky Flats Plant

 where  an  individual  in.the  general  population could be exposed as  a

 result of transuranium contamination originating from the Plant. This

 location  is  in the  downwind direction  of  the prevailing winds  that blow

 across the Rocky Flats Plant  and, therefore, would  represent  a worst

 case for  offsite exposure.

                             es _

                                   225
* 1 femtocurie =10    curie.

-------
 From Figure 7.2 it can be seen that stations S-35,  S-36,  S-37,  S-38,  and


 S-39 are located along Indiana Street.  Station S-37 reported the highest


 annual average for 1975 of 0.056 .fCi/m3 (Table,7.2).   Assuming  this


 level to continue for the next 70 years,  the 70th year dose rates to


 lung and bone can be calculated.

                                                              o
      According to Table 7.3,  an air concentration of  1.0  fCi/m   for 1 ym


 AMAD aerosols of Pu-239 would produce a 70th year dose rate to  the


 pulmonary compartment of 0.38 mrad/yr;  therefore, proportionally,  a


 concentration of 0.056 fCi/m3 (S-37)  will  produce a 70th  year dose rate


 of 0.02 mrad/yr.   The bone dose rate  associated with  this level of Pu-


 239 according to Table 7.4 will be 0.009 mrad/yr  in the 70th year.


      Data on the air concentration of Am-241 have been reported by HASL


 (2)  for the  years 1970 through 1974.  These  data show the americium


 levels,  measured  at  the perimeter  fence ,of the'Plant,  to  be  approximately


 11% of  the Pu-239 levels.   HASL has also projected  that the  Am-241


 activity level will  reach  its  maximum value  arising from  the decay  of


 Pu-241  in the year 2033, at which  time it will amount  to  18% of  the Pu-


 239  activity.  For the calculation of the dose rate from Am-241, it is


 assumed  that'Am-241  is  at  the maximum of 18% of the Pu-239.  The 70th


year dose rate corresponding to a  concentration of 1 fCi/m3 of Am-241 is


 0.4 mrad/yr; proportionally, an air concentration of  (0.18)  (0.056

     3
fCi/m ) would produce 0.004 mrad/yr to the pulmonary compartment.  The


associated bone dose would be approximately 0.002 mrad/yr.


     Based upon these calculations, the  total pulmonary dose rate after


70 years of exposure for an individual living along  Indiana Street
                                  226

-------
                           FIGURE ;7.2

                  J    '   -  " „ ,  ,  .   ,"""''   "'-'«"

                       LOCATION OF


      OFF-SITE AMBIENT AIR SAMPLERS
COAL CREEK
               O       ©SUPERIOR
              MARSHALL
                                                            IN
               S-32
       0]BROOMFIELD


©WALNUT CREEK
                               LEGEND


              O ON-SITE AIR SAMPLERS

              A AIR SAMPLERS, 3 TO 6 KILOMETERS ( 2 TO 4 MILES) DISTANCE

              © COMMUNITY AIR SAMPLERS   '   .
                       227

-------
 would be 0.024 mrad/yr, while the associated bone dose would be 0.01




 mrad/yr.  These dose rates are approximately 2.5% and 0.3% respectively




 of the lung and bone dose rates recommended as guides by EPA (1).




 Individuals living further away from the Rocky Flats Plant should




 receive even lower doses than these due to the lower air concentrations




 reported for the nearby communities.  Based upon the preceding analysis,




 the direct impact of the onsite contamination upon the off-site environ-




 ment can be judged to be small and well within the EPA guidance limits.




 7.2.3     Calculation of Inhalation Doses Due to Off-site Contamination




      A complete assessment of the inhalation pathway for the Rocky Flats




 vicinity must also consider the potential hazard from the low levels  of




 contaminated soil which already exist  off-site.   Questions have been




 raised as to the effect of this  material in producing localized exposures




 which are not necessarily reflected  in the data  obtained through, the  air




 monitoring network around Rocky  Flats.   These  inhalation exposures  can




 arise through various mechanisms  including:  wind  resuspension  of con-




 taminated  soil, vehicular and mechanical disturbances  of  soil,  accumu-




 lation and resuspension of dust within  the home, as well  as the resuspension




 of contaminated soil attached to  clothing.  The following analysis will




 attempt to investigate  these exposure mechanisms and assess their potential



 impact.




     Wind Resuspension




     Figure 7.3 shows the off-site soil contamination contours reported




by HASL in 1970 (3).  More recent soil sampling programs in 1975 (9)




have not shown these contours to have changed significantly from the



1970
                                  22B

-------
 ROCKY   /   //^
I FLATS   /'    //
IPLANT  /   //
 ERDA PRO? = * I r     s '-.  '•
        BOUNDARY   O.\  \
                                     ^_n  -^
       FI G U R E1.3 Plutonium-239 Contours Around Rocky Flats (pCi/rrr)

                            (adapted from FCrey, 1970)
                        990
                        4^4 &/ VJ*

-------
                                    10
report.  The highest off-site contour shown by the HASL data is 0.05


     2
yCi/m .  These contours were developed based upon an inventory sample to



a depth of 20 centimeters.  What is important in assessing the resuspension



of soil, however, is only the material existing near the surface.  In



the derivation of EPA's guidance (1), the layer subject to erosion was



considered to be the top one centimeter.  Based upon the HASL soil depth



profiles, Anspaugh (10) has estimated that approximately 20% of the



total activity is contained within this first centimeter1  Therefore,


                                       2                               2
the highest contour value of 0.05 uCi/m  would correspond to 0.01 iaCi/m


                                                              2
when corrected for a 1 cm. depth.  On a mass basis, 0.01 yCi/m  is



equivalent to approximately 2 disintegrations per minute per gram of



soil, i.e., 2 DPM/gm.  The off-site area bounded by this contour is



approximately two square kilometers and soil within sthat area would be



projected to be at or above 2 DPM/gm.  Beyond this area, off-site soil



will generally be below this value.



     In developing its guidance to other Federal agencies on environmental



levels of the transuranium elements, EPA used the mass loading approach



as an indicator of the general resuspension by wind over large land



areas.  Because of technical shortcomings identified with the mass



loading approach, the agency staff modified the concept to assess small



areas of contamination (area correction factor) and.to reflect a nonuniform



distribution of radioactivity with soil particle size (enrichment factor).



This latter modification is particularly important because transuranium



activity associated with soil particles within the respirable range is a



greater hazard than it would be if associated with' the larger nonrespirable



particle sizes.                                                       ,
                                 230

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                                   11
     The mass loading approach assumes the loading of the air with



particulates to be an index of resuspension and derives the airborne



concentration of a specific radionuclide by a comparison with its



concentration on the adjacent surface (11).  Specifically,
     Air Concentration (fCi/ 3) = Soil Concentration (U 1/m ) x
      .'  -   .,....-.      m          '     •  '  .      •„-.••- '.,'


     Mass Loading (ys/m3) x U.C.*
Eq. 1.
     Airborne pafticulate mass loading is one of the criteria for clean




air standards, and measurements are widely available for urban'arid



nonurban locations through"the National Air Surveillance Netwdirk (NASN).




The data recorded at nonurban stations are a better indicator of the



levels of resuspended material than are urban measurements1  In general,




annual mean mass concentrations of airborne pafticulate material at the



nonurban stations range from 5—50 micrbgrams per cubic meter"(Figure '



7.4); the mean arithmetic average for 1966 of all 30 nonurban NASN


                  .  3 ..     .     •   •                 -, ..   ..-,:•;.-
stations was 38 yg/m (11).  From Figure 7.4 an estimate can be"made'of '



the average mass loading for the general area in which Rocky Flats is"


                                        3              .   .  .

located and it would appear that 15 Jig/m  is reasonably representative



of this area on an annual basis.



     Simple application of the mass loading approach without corisid-



deration of the activity distribution as a function of particle s±zeis



not appropriate, however, since that would imply a uniform distribution



of activity with particle size as well as a uniform   -   •
*Where U.C. is the units conversion factor based upon the depth of

 sampling and the soil density.
                                 231

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                   12
ANNUAL aiEAPi E1ASS CONCENTRATIONS (^jg/ni3) OF AIRBORNE
PARTICLES FRQivl NON-URBAN STATIONS OF THE U.S. NATIONAL
         AIR SA&V1PLJHG NETWORK. 1964 - 1965

                     FIGURE  7.4
             232

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                                  13
resuspension of all particle sizes.-  This has-not been found to be the




case at Rocky Flats (12,13) or at other plutonium contaminated sites




(14).  In addition, an important consideration in assessing the potential




exposure due to contaminated soil is the amount of activity associated




with particles within the respirable size range.  Johnson (15) has




suggested that sampling of only those particles in a soil sample which




are within the inhalable size range (generally < 10 ym) would give the




best measure of risk to the public health around Rocky Flats.  However,




the weight fraction of particles in the less than 10 ym range is small




in most soils, and sampling, separation, and analysis techniques are..




correspondingly more difficult and inaccurate.   Also, a substantial




contribution to other possible pathways (e.g. ingestion) may be via




larger particle sizes and measurement of the contribution of only the




inhalable fraction would not provide all the information that is required.




     In order to adequately assess the potential hazard of the inhalable




fraction of soils, while retaining the advantages and convenience of




analyzing the entire soil sample, the agency staff modified the mass  :




loading approach by use of an "enrichment factor".  While such a concept •




does not have universal acceptance, and the scope of its applicability




has not yet been determined, the agency.'staff believes that it represents




a useful method for the purpose intended and it has therefore been used




in this evaluation.

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                                   14





      Enrichment Factor




     The "Enrichment Factor" is intended to 1) give a mathematical view




of the different fractions of the total radioactivity associated with




particles of different size ranges, and 2) address the problem of the




nonuniform resuspension of particle sizes.




     The inhalable fraction of the soil is weighted by considering the




relative distribution of activity and soil mass as a function of particle




size for representative samples of soil.  To accomplish this, the sample




of contaminated soil is segregated into "n" size increments and the




activity and mass contained within each size increment is determined.




The factor g, is then defined as the ratio of the fraction of the total




activity contained within an increment "i" to the fraction of the total




mass contained within that increment.  A value greater than 1 for g±




implies an enrichment of activity in relation to mass, while a value




less than 1 indicates a dilution of the activity with respect to mass.




For g. equal to 1, the fractions of the activity and of the total mass




contained within increment "i" are the same.




     The nonuniform resuspension of particle sizes is also considered by




measuring the mass loading as a function  of particle size.  The fraction




of the airborne mass contained within each size increment "i" is then




calculated and designated as f  .  The factors of f. and g^ are then




incorporated into the mass loading formulation as follows:









Air Concentration. = Air Mass Loading xf±x Soil Concentration xg±     Eq. 2
                                  234

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                                    15
Summation over all  the  size  increments  results  in the  total  air  concentration:



     Air Concentration^ Air Mass Loading  x Soil  Concentration
     ••  n             '        •     •           -      ,     ,
     x £   f±g±                                          !          Eq.  3
   . .  • i=l ,	 .    ., ,, ....,,     ....
              n                          "              "     ^  •--.-••.-•-
     The term E   f .g.  weights  the  contribution of the plutonium from
              1=1   1 x
each soil size fraction .to .the  total resuspended  material, thereby

-taking into account both the nonuniform resuspension of particles sizes

and .the nonhomogeneous  distribution of. activity with particle size.

     n
     I   f .g. is the "enrichment factor."                   .  .'•,.
     i=l

     Data on the distribution of plutonium with soil particle size has

been obtained by the EPA (12) and by Tamura (13)  for the vicinity

around Rocky Flats  (Table 7.5).  The ratio,  g±, has been calculated for

each size increment and indicates an enrichment of activity to mass

associated with soil particles within the  respirable size range.   To

obtain, f.^, the data obtained by Chepil (16) for  fields undergoing wind

erosion in Colorado and Kansas were used.   The results of his findings

have been conveniently  plotted by Slinn (17) and  reproduced as Figure

7.5.  Comparison of Chepil's data with another study substantiates the

applicability to the Rocky Flats situation.  Chepil found 30% of  the

airborne mass to be below 10 urn versus a study by Willeke (18) in an

area outside Denver where approximately 33%  of the measured airborne

mass was below 10 ym.   Values for f  used  in this analysis are included

in Table.7.5.
                              235

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to
CO
CD
                                                                                                      IUU
                                                                                                         m
                                                                                                         D
                                                                                                         m
                                                                                                         Z
                                                                                                         H
                                                                                                         m
                                                                                                         33

                                                                                                      10  °
                                                                                                         33
                                                                                                         CD
                                                                                                         O
                                                                                                         33
                                                                                                         Z
                                                                                                         m
                                                         33


                                                         O
                                                         r-
                                                         m
                                                         v>
                                                                                                         b
                                                                                                         H
                                             T~
                                             20
-T	r-1—I	1	1	T-
 30  40  50 60  70  80
                   10     20  30  40  50  60  70  80   90   95   98  99    99.899.9

 PERCENT OF MASS ASSOCIATED WITH PARTICLES OF LESS THAN EQUIVALENT DIAMETER


PARTICLE SIZE DISTRIBUTION OF RESUSPENDED SOIL


                                 FIGURE  7.5
                                                                              99.99

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                                17
     Correction for Area Size


     Use of the mass loading approach implies that the air concentration


is at equilibrium with the ground surface, i.e., a steady state situa-


tion exists in which the amount of material coming up from the surface


is balanced by the rate at which material is depositing back onto the


surface.  In the strictest sense this limit can only be achieved for


source areas approaching infinite dimensions.  For sources of finite


dimensions, a correction must be applied for area size.


     Although techniques are presently under development to calculate


the air concentration arising from an area source, no generally accepted


method has yet" been identified.  Usually, these approaches make use of a


standard diffusion equation, modified to handle area sources.  One such


equation is the Sutton-Chamberlain diffusion equation:
= i- [exp(-
            4VdDl
                           n/2
                                           4 V
            /if C0 n u
                                                     .

                                            VTT C  n u
                                               Z
                                                                    Eq.4
                           ----•-'»  -j
     where  x  is  the  air  concentration,  Ci/m


            Q   is the amount  of  activity resuspending  per unit  area,
            A                  £
            per  unit time, Ci/m  sec.


            V, is the particle deposition velocity, m/sec.


            D   and P_ are the distances  from the receptor to  the nearest


            and furthermost edges  respectively of the  source  area,  meters,


            u  is  average  wind speed,  m/sec.
                                  23?

-------
                                  18
            C  and n are Button parameters representing the;  .      ,  .
             z


            meteorological conditions.      ••••.,



     If the receptor is placed at the downwind edge or within the source



area, D- = 0 and Eq. 4 reduces to:               ,          .    .
X. .  -
II -•»<-
                        4VdD2
                                n/2
)]
                                                                  Eq.5.
                           Cz nu
     For source areas approaching infinite depth, D_ -> <» and Eq.  5



becomes:
      QA   vd
                                                                   Eq.6.
     Comparing Equation 5 with Equation 6 shows that    '            .





          4V  D n/2
[1- exp(-   d  2    )] is the correction term to be applied for areas


          /iF C  n u
              z


of finite size. .                              ,                     ,



     The area under consideration in this analysis has been described


                                                            2
earlier.  It is bounded by Indiana Street and the 0.05 yCi/m  isopleth



(Figure 7.3) with a width in the downwind direction of approximately 1



kilometer.  This is the most highly contaminated off-site area and



includes sites of projected residential development.  The meteorology



for the Rocky Flats area has been described (9) to have neutral stability



at least 50% of the time with a mean wind speed of 4.2 m/sec in 1975.



Healy (19) has suggested values for the parameters required in Equation



4:  for the situation of neutral stability, Healy suggests C  = .1 and n
                                                        ;    Z       ' , ,.


= .25, while the ratio  d/ , which depends upon the
                                238

-------
                                    19

 surface roughness, ranges ;between  0.003  and-0.008 for grassland, 0.005

 will be assumed.  Therefore, from  Equation^  the  correction factor for

 the area under consideration is 0.66.        ,           -      .„   ,

      Calculation of the Average Air Concentration Due to-Wind

      Resuspens ion                    •  .   ...

      The average soil concentration for  the area  is  riot known,  but it
                                      2
 would be somewhere between 0.05 yCi/m  and  the next  higher isopleth of
          2     '•"   /••  • ' '  ':'   " •' "•'  •-  ":"- .-"•• '-'•"•'• 2  '   ' ' '""   "'  '
 0.5 pCi/m .   For calculational purposes,  0.25 yCi/m   will be assumed or

 approximately 10 DPM/g (based upon 20% of the radioactivity within the

 first centimeter).  By using the parameters developed in  the previous

 sections for the Rocky Flats area, one can  estimate  the average air

 concentration due to wind resuspension:       ,       ;  •;.  .,...-.•-,

 Mass Loading x Soil Concentration  x Enrichment Factor x Area Correction

   Air Concentration
 15
X10DPMX1.63X.66X10.
   Ci
    m
2.22xl012.DPM
                                                     = Air' Concentration
                                      0.11. fCi
                                                 Air  Concentration
                                            m
 The calculated value of 0.11 fCi/m  agrees with the data  obtained for

 the sampling stations along Indiana Street, arid, as demonstrated  earlier,

 this concentration of airborne plutonium would produce exposures  well

 below EPA's guidance limits.

      Inherent in the above calculation were some conservative  assumptions.
',  ">••'     ,V    - •*'.  -^    . ,  '_     i    '  ' f"" • '   -' *   „ ^ -, tj,   , „,, ' .;,, „„, .,,-,»-,   ".,'.,-
      >      • ••   "   .-„ '^ - • -v» , , -i  , ,i, ,. •-, i, ~ i - . ,f -, \jt - , .«• 
-------
                                 20





the contaminated area in the direction of the receptor.   In reality,  the




reported (9) wind rose for Rocky Flats indicates that the wind blows




from the westerly direction only about 50% of the time;  the remaining




time it will be blowing from the direction of less contaminated land




and, therefore, less radioactivity would be available for resuspension.




Secondly, in deriving the area correction factor the effect of breathing




height was ignored with the ground level concentration being calculated.




This is a conservative assumption since the airborne concentration will




decrease as a function of the height above the ground.  Although such




refinements could have been incorporated in the calculation, it was not




felt to be necessary because even these conservative assumptions resulted




in air concentrations well below the Agency's proposed guidance.




     Resuspension of Soil by Mechanical Disturbances




     The use of land contaminated with transuranium elements in the




vicinity of Rocky Flats for agricultural or building purposes can result




in localized resuspension and presents a potential inhalation hazard  to




individuals in the immediate vicinity of the operation.   In the vicinity




of Rocky Flats, there is some farming of wheat and the raising of corn




for livestock feed.  Future development of the land for residential




purposes is also being advocated.  Although only a limited amount of




experimental data is currently available as a basis for an assessment of




the inhalation hazard from such activities, some conclusions and recommendations




can be made.




     In assessing the agricultural situation, data obtained by Milham




(20) have been used.  In that study, a field contaminated
                                  240

-------
                                  21

with plutpn-ium. near the Savannah River Facility was subjected, to various

plowing and seeding activities associated with planting wheat.   The

increase in the airborne activity above that from normal wind resuspen-

s ion was monitored at the location of the tractor operator and at the,

downwind edge of the field during , the various activities.  An average

increase of a factor of 30 was observed ..in the level of resuspended

plutonium at the location of the tractor operator and an increase of a

factor of 5 at the edge of, the field.  Based upon these observations,

the average air concentration .for the year can be calculated for these

two locations, assuming that the field is cultivated 30 days. of the year

for 8 hours per day.  Again the area under consideration will be that

area of highest off-rsite contamination described earlier with an average

soil contamination level of 10 DPM/g.  In the previous discussion of

wind, resuspension, this level of soil activity produced an air con-
                        Q
centratipn pf  0.11 fCi/m, .  From Milham's data, this activity level
                           o
would increase to 3.0 fCi/m  at the-location of, the .tractor operator and  ,

to 0.55 fCi/m  at the edge of the field during the agricultural operations.

The annual average, concentration at .each location is therefore: . :

     1.  Tractor Location, Average Annual Air Concentration
3.0 fCi/m3 x |T x —^ + 0.11 fCi/m3 x if x
       330
       360 ,
     = 0.2 fCi/
             24   360
                3
                                            24    360
                                                    + 0.11  fCi/m x
m
      2.   Edge of  Field,  Average Annual Air  Concentration
0.55 x
             24
                 x
             360
  + 0.11 x ~ x
         •  24-  360,
                                   + 0.11 x
                                          •  360
                                                      - 0.12  fCi/m
      When these annual Pu-239 concentrations are compared to the value
             3
 of 2.6 fCi/m  which was calculated by the PAID code to correspond with

                                 241    -

-------
                                    22

 EPA's  dose limits,  one  can  conclude that agricultural operations  in  the
 area of Rocky Flats would produce  activity  levels well within EPA's
 guidelines.  In  addition, after  the first plowing cycle, the surface
 concentration should .be diluted  by mixing with soil from below the
 surface and subsequent  plowings  would produce air concentration lower
 than that  of the first  year.
     Regarding building activities, one can make projections based upon
 the agricultural situation  examined above.  There does not appear to be
 any reason why building activities, such as excavation and grading!
 should produce higher instantaneous air concentrations than those
 observed during  agricultural plowing and, therefore, they should not
 present a  more restrictive  situation.  In addition, although the building
 activity might take place for longer than the 30 days assumed in the
 plowing situation,  it must  be kept in mind  that the EPA guidelines are
 based  upon a chronic exposure for  70 years.  Certainly, the bulldozer
 operator would not  be engaged in a building operation in an area of   '
 transuranium contamination  for that number  of years.
     Resuspension of Dust Within the Home
     The total amount of soil continuously  in the home is not known but
                        2
 an assumption of 10 g/m has been made (21).  This amounts to about 3
                               2
 Ibs of soil  in a modest 1500 ft  house.  Because the floors are harder
 and smoother than outside surfaces, the resuspension from them will be
higher.  Resuspension factors of 10   m   have been used in the past to
predict exposures in the work place and studies of PuO? deposited on
 indoor surfaces have been consistent with a resuspension factor of 10
m'1 (22).

-------
                                   23
     The following exposure situation is postulated:  the individual is



exposed to contaminated dust in the home for 24 hrs/day, 7 days/wk, for



70 years.  The dust in the home has the same activity/gram as outside

     .  :.. .     ,     .  _    , ,     ..   '••.••.       •      2     '

soil and has an areal distribution within the home of 10 g/m .  The air



concentration resulting from resuspended dust at 10 DPM/g would be:




     10 DPM
            x
Ci
                10g   10~6
	.	 - • 	  -yr   Wi v  • "•   —


2.22xl012 DPM    m2    m
                                           airborne dust concentration
                     3
          0.045 fCi/m  = airborne dust concentration




     Again the level of airborne activity would result in dose rates



well within EPA's guidance limits.                            ,    ,



     Resuspension of Dust from Contaminated Clothing         -..-•,



     Healy (19.)..-has. assumed that in a desert environment there will be 1


     f\        r\

mg/cm   (lOg/m) of dust on clothing.  While it would certainly be, less



for nondesert .environments, this value will also be assumed  for Rocky



Flats.  Because of the proximity of the  contamination to the nose and   ,



the mouth, a  resuspension factor higher  than the normal outdoor resuspension



factor  will be assumed.  For  this calculation, a value, of 10  m   will



be assumed to be sufficiently conservative  (10   m , is 3-4  orders of



magnitude higher, than values  of wind  resuspension  factors observed at



Rocky Flats).  Therefore, the resultant  air concentration is:
      10
            10 DPM

               ~
        Ci
                      2.22xl012 DPM
                                     x
                         10
                        -6
                                         _i
                             0.045  fCi/m"
                                        m
                                  243

-------
                                   24
     In addition to this air concentration being much lower than EPA's




guidelines, the period of exposure would not be continuous since the




clothing would be removed at least during sleeping.  Therefore this




pathway would present no apparent hazard.




     7.2.4     Conclusion




     None of the inhalation pathways considered in the environs surrounding




the Rocky Flats Facility has resulted in doses close to the guidance




limits recommended by EPA for the transuranium elements.  Even if the




conservative assumption is made that these exposures are occurring




simultaneously, the combination of pathways would amount to only a few




percent of the guidance limits. Even though every conceivable inhalation




pathway was not evaluated, it does not seem likely that one exists which




would have a combination of resultant air concentration and period of




exposure to produce significant doses compared to the guidance levels*
7.3  Ingestion Pathway




     7.3.1  Plutonium and Americium in Drinking Water




     Wastewater discharged from the Rocky Flats Plant as well as surface




runoff from the Plant site is collected in a number of holding ponds




where it is monitored for its radioactivity content before being discharged




into either Walnut or Woman Creek.  Walnut Creek empties into the Great




Western Reservoir which provides part of the drinking water supply for




the City of Broomfield, while Woman Creek eventually empties into Standley




Lake which is a drinking water supply for the City of Westminster.

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                               .;:  25    ._ _          '          .   	'


     The Rocky Flats water monitoring program consists of 1) effluent

monitoring of. the water being discharged from the holding ponds into

Walnut and Woman Creeks, 2) the monitoring of groundwater and 3) the

monitoring of the regional water supplies.  In monitoring public water

supplies, samples are collected and analyzed from the drinking water

reservoirs (Great Western and Standley Lake) as well as the finished

water in several nearby communities.  As with the air; monitoring, the

results of this sampling program are reported regularly to the responsible

Federal, State, and local government agencies and published on a yearly

basis.  According to. the 1975 published data  (9) the average  concentrations

of plutonium and americium  in finished water  for the region were

<  .027xlO~9  yCi/ml and  <  .032xlO~9  uCi/ml, respectively.  The concentration

levels  of plutonium  and americium in the  drinking water of  the various

communities  surrounding Rocky Flats are given in Table  7.6.   Included in

this/ Table are  results  obtained by  Poet and Martell (23)  in 1970.         . ..

Limited comparison of  the  two  sets  pf  data shows little change  in  the
                                                        ' "    .    I
activity levelsin  £he drinking water  during  this  five  year period.  As

with the airborne concentrations,  these environmental levels-need  to be

put  into the perspective  of EPA's  guidance limits.

      7.3.2   Bone Dose Resulting Due to Ingestion of Water

      Assuming that  the concentrations  of  Pu-239 and Am-241 in drinking

water are those reported for the city of  Broomfield (the  highest con-

 centrations reported for the more immediate surrounding communities) and

 that the consumption rate of water is 1.2 liters/day (ICRP Committee

-------
                                    26




  II)  the annual water ingestion rates are:


  Pu-239, Annual Ingestion Rate                                   .


            —9
      0.04x10    ltd  x 1200 ml  x 365d = 18 pCi/yr

                 ml        day    yr




 Am-241, Annual Ingestion Rate



     0.029xlO~9 uCi  x 1200 ml  x 365d = 13 pCi/yr

                 ml        day    yr


     Conversion of the above ingestion rates into dose rates can be


 achieved through the use of Tables 7.7 and 7.8.   The development of


 these tables has been described in Annex III of  EPA's guidance (1).


 Table 7.8  has been normalized to an ingestion rate of 1000  pCi/yr of


 various transuranium oxides and relates the years of ingestion to the


 resulting  dose rate.  Plutonium and americium found in treated tap water


 would probably be in a chemical form which is more soluble  than the


 oxide and  which would have  a higher GI  tract  transfer fraction (24).


 For nonoxide  forms,  as shown in Table 7.7,  the values listed in Table


 7.8 should be increased by  a factor of  10  for plutonium, while  the


 americium  values  remain the  same.   Based upon these conversion  factors,


 the bone dose rate after 70 years of  ingestion of drinking water would
           o

be 8.8x10" mrad/yr for Pu-239 and  6.2xlO~3 mrad/yr from Am-241.  These


values are considerably below EPA's recommendation of 3 mrad/yr to bone


from the transuranium elements.                                        •


     7-3.3.  Bone Dose Due to Ingestion of Foodstuffs


     At present limited agricultural production is carried out  in the


environs of Rocky Flats.   Most of the food consumed locally is  produced
                            246

-------
                                   27
at considerable distances from :the Rocky Fiats Plant.  Other than a few


family garden plots, the only crops grown locally are wheat and alfalfa.


A few cattle also are raised in the Plant's vicinity.  Since future


residential development is projected for the Rocky Flats area, it would


be reasonable to project a concurrent increase in family gardening.


Therefore, an assessment has been carried out of the possible dose rates


associated with the consumption of  foodstuffs which  might.be. produced


locally.  Because  food  sampling data are not presently available  for the


Rocky Flats  area,  estimation of the potential doses,are based upon data


developed in other areas contaminated with  transuranium elements  and



from laboratory experiments of transuranium uptake by foodstuffs.  ,


Conditions at Rocky Flats are  not different enough  to invalidate the use



of data developed in these other environments.


      For purposes of this assessment,  the ingestion rate of the transuranium


 elements by people is considered to! be, .the product of the, rates at which


 different contaminated materials are ingested and,the concentration of


 the transuranium elements in each material.                ,.


      To  put these  calculations into perspective, the formulation of


 Martin and Bloom  (25) was adopted which relates the ingestion rate (Hi


 for  a particular nuclide to the average concentration of that miclide  in
  soil (C )  through the following formulation:
         s
       H
                                                                Eq.  7,
                                 24?

-------
                                    28
 where I± is the ingestion rate of a particular item and DI is the discrimination


 ratio between that substance and soil.  This formulation makes for easy


 translation of environmental levels into dose rates and, thereby, allows


 direct comparison with EPA's guidance limits.


      The soil concentration used in this assessment is the same as that


 developed for the inhalation pathway calculations, i.e., 0.25 yCi/m2 for


 Pu-239 and 0.045 pCi/m2 for Am-241 (18% of Pu-239 levels at the time of


 maximum ingrowth).  If this activity is evenly distributed throughout


 the top 20 cm as a result of plowing,  the average concentration,  C ,  in
                                                                   8

 units of pCi/g would be:
 0.25 uCi     10   pci
        m
                   yCi
  cm        1

X  Ig  x 20 cm
                                           x —
                                                m
104 cm2
=1.25 pCi/g Pu-239
 and 0.22 pCi/g'(Am-241).


      The materials  considered by this  analysis  to be  produced  on  this


 land and consumed by individuals living  in  the  area are leafy  vegetables,


 other food plants,  cow milk,  and beef.   Also  the casual and deliberate


 ingestion of contaminated soil will be considered.


      Leafy Vegetables  and Other  Food Plants


      Plants grown in soil containing the transuranium elements can


become contaminated  through uptake by the roots and systemic incorpora-


tion; in addition, the outer surfaces of the plant can have contaminated


soil deposited upon  them as a result of resuspension.   Numerous studies


have been conducted and several reviews  (26, 27, 28)  have been published


 covering the range  of  discrimination factors  that have been observed in


 laboratory and  field studies,  generally the discrimination ratio for

-------
                                   29
                                            .        -4      -6
incorporation of Pu-239 into the plant is between 10   to 10   on a

                         — T       — 0
fresh weight basis and 10   to 10   for deposition on the plant surface.


The internal incorporation of americium-241 may be as much as 50 times


higher than that of plutonium, due to its greater solubility.  Generally,


uptake factors for garden vegetables are at the upper end"of the range;

                                                                  -4
therefore, for calculational purposes.a discrimination ratio of 10


will be assumed for internal deposition and 10   for external deposition

                                                                     _3
when computing the intake of Pu-239, and corresponding ratios of 5x10'


and 10"1 for Am-24l.   Since the calculations are for food in a table-


ready condition, decontamination of the food during processing must also


be recognized.  In doing so, the assumption of Bloom and Martin  (25)


will be used; namely,  90% of the contamination is washed off leafy-


vegetables and  99% of  the contamination is  removed from other food


plants during washing, peeling, etc.  Likewise, the consumption  rates  of


foodstuffs obtained by Martin  and  Bloom from the USDA have  been  used


after conversion  to a  fresh weight basis  (on the basis .that vegetation


is  70% water).  Table  7.9 contains the resultant ingestion  rates and


discrimination  ratios  used  in this assessment.


      Equation 7 was used to convert  the  ingestion  rates  and discrimination


 factors  of  Table  7.9  into annual  intakes  of plutonium and americium.   In


 carrying out the  food  pathway calculations, the  assumption  was made that


 25% of  the  entire intake for an individual arises  from  foodstuffs pro-


 duced locally on land contaminated, with  transuranium elements.

-------
                                    30
      The resultant ingestion doses are given in Table 7.10.  In converting


 the annual radionuclide intake to dose rates, Table 7.7 and 7.8 were


 used with the following assumptions:


      1.   the duration of ingestion is 70 years


      2.   externally deposited material is in the oxide form


 and  3.   material biologically incorporated in plants and animals is
           assumed to have a greater fraction transferred from the G.I.
           tract to the blood.   For plutonium,  according to Table 7.7,
           this results in an increase of a factor of 50 in the resulting
           bone dose and a factor of 5 for americium.

      Ingestion of Cow Milk


      Martin and Bloom have developed a discrimination  factor for dairy

               —8
 cows  of 3.2x10   based upon assumptions  of soil  and vegetation  consumption


 by cattle.   Using this value and  again assuming  that 25% of  one's  diet


 is locally  produced,  one can calculate the ingestion rates of Pu-239  and


 Am-241  as a  result of milk consumption:
H  (Pu-239) = C  ID
              s

           = 1.25 £Ci   436e    .25 x 365 dajs
                        day  x  .         ~~~
                  1.6x10" pCi/yr
H (Pu-239)


H (Am-241) = .18 H (Pu-239)


H (Am-241)
                                               yr
                                                     ~9in
                                                     3'2xl°
                                                           -8
                   28xlO~3 pCi/yr
     Since these transuranium elements would be biologically incorporated,

the dose rates of Table 7.8 would be increased by a

-------
                                  31
factor of 50 for Pu-239 and a factor  of  5  for  Am- 241.   The resultant



bone doses attributable to the consumption of  milk are given in Table



7.9.


          Ingest ion of Beef



     Similarly., Martin and Bloom developed discrimination factors for



beef muscle and beef liyer and these  have  been utilized in our calculations



of ingestion rates:



     Beef Muscle
H (Pu-239) = C  ID
              S
 ,':..,•-... v  ::..'•'  •"

H (Pu-239) - 1.25 pCi

            ,\  . . '.. 8
                                       .

                                   •day-.

                  .25 x 365d

                  • .-.   ;   yr -•
                                                       3.3xlo

                                                           -
                                                             -5
          H (Pu-239)  = 1.02 pCi/yr



          H (Am-241)  = .18 H (Pu-239)



          H (Am-241)



      Beef Liver



          H (Pu-239)
l.SSxlO"1 pCi/yr
1.25 £Ci   13g   .25   365 day   2.xlp
         jC ••   3t     3t *    -,'    i • «
      g    day              yr
                                      -3
           H (Pu-239)  - 2.96 pCi/yr



           H (Am-241)  = .18 H (Pu-239)



           H (Am-241)  = 5.33X10"1 pCi/yr
 Assuming that transuranium material is biologically incorporated, the



 resultant bone dose rates after 70 years of ingestion have been calculated



 and are included in Table 7.10.

-------
                                    32
 7.3.4     Bone Dose Due to Soil Ingestion




      Casual Ingestion




      Bloom and Martin (25) have assumed a casual ingestion rate for a




 desert environment to be approximately 3-4 g/year.   Likewise,  Rogers




 (21)  has estimated the accidental ingestion rate of soil as a  result of




 hand  to mouth transfer to be 3-4 g/yr.   Based upon  these estimates,  one




 can calculate the plutonium and americium ingestion and resulting dose




 rates.   The ingestion period is assumed to be 70 years  and the surface




 soil  concentration of Pu-239 is that  developed previously for  unplowed,




 undiluted soil in the vicinity of Indiana Street; i.e.,  10 DPM/g  (4.5




 pCi/g).   The americium concentration, also as before, is assumed  to  be




 at  its maximum contribution of 18% or 0.8 pCi/g.  The resulting bone




 dose  have been calculated assuming the  transuranic  material is in the



 oxide form and these  have been included in Table 7.10.



      Deliberate Ingestion




      Healy (29) has addressed  the problem of  deliberate  soil ingestion




 by  children below the age of five.  After  reviewing the  limited available



 data  on the topic, he concluded  that a  deliberate soil ingestion rate  of




 20  g/day would  be a reasonably severe case.  Applying this  estimate  to




 the Rocky Flats situation would produce the following ingestion rates



 for deliberate  soil ingestion:
          H (Pu-239)
C  ID*
 s
4.5 pCi/g x     x
            day
                                         365 da^s

                                              yr
          H (Pu-239) = 3.24xl04 pCi/yr
*  D is equal to 1.0

-------
                               r-r:  33
          H (Am-241):- .18 (Pu-239)




          H (Am-241) = 5.84xl03 pCi/yr





     Since this condition of excessive soil ingestion would occur over a




relatively few years, the resultant dose rates were calculated assuming




the period of ingestion to be 5 years and are included in Table 7.10.




7.3.5     Conclusions



     From the results presented in Table 7.10, one can conclude that,




even for the unlikely case where the calculated doses for all pathways




are additive, the doses received by ingestion would be well below the




EPA guideline of 3 mrad/yr to bone.  In reality, an individual in the




vicinity of Rocky Flats would receive much lower doses than those




calculated.  It is  deemed very unlikely that one could identify other




possible ingestion  pathways of such magnitude that they would result in




bone doses exceeding 3 mrads in any year.

-------
                                                         Table 7.1
                                     SURFACE AIR PU-239 CONCENTRATION AT ROCKY PLATS
                                                 ATTOCURIES/CUBIC METER
                JAN.
                FEB.
MAR.
                                           APR.
                                           MAY
                                                             JUNE
                                                             JULY
                                             AUG.
SITE
                                                                                        SEP.
                                                                                        OCT.
                                                                        NOV.
                                                                                                                  DEC.
1970   —       *-       —       __       __      1990.00  1250.00   790.00
1971  1960.00   —      7140.00  9730.00  4920.00  3800.00  2980.00  3530.00
1972  5430.00  1670.00  4610.00  1460.00  2080.00  6610.00  4720.00  1380.00
1973  1160.00  3640.00  2520.00   612.00  1780.00  3040.00  2920.00  3320.00
1974   402.00   802.00   891.00  1810.00  3060.00  5470.00  2670.00  3330.00
1975  1260.00  1360.00  1780.00  2180.00  2190.00  1160.00   567.00   426.00
19.76   680.00  1240.00   864.00   —       —
                                                                                       850.00   693.00  2260.00   962.00
                                                                                      4040.00  5770.00  5770.00  3160.00
                                                                                               1620.00   498.00  1860.00
                                                                                      1050.00  2010.00  1810.00  1690.00
                                                                                      1120.00   407.00   580.00-  643.00
                                                                                       179.00   —      1220.00   655.00
SITE 02 •,
ro
IF*



SITE #3




SITE #4 "


	 V

1972
1973
1974
1975
1976

1972

1973
1974

1974
1975
1976
FA n A T A

	
37.80
16.80
141.00
12.20

«•»

18.40
21.70

—
288.00
184 .-00

—
57.7.0
23.20
34.70
23.10



41.70a
39.10

— ..
399.00
303.00

—
55.80
462.00C
56.80
14.40



24.20
163. 00C


1850.00
72.60

—
716. 00C
135.00
39.70
—



24.00
283. 00C

--.•-'
254.00
236.00

—
51.80
176.00
—
—



40.40
—

1460.00;
139.00
109.00

98
57.70 92
140.00 78
™* 27
— — HH


""*** ~* ~
42.00 25
— —

-758.00 1430
684.00 118
319.00 98

.90
.10
.70
.40




.80


.00
.00
.20

55.50
65.00
58.10
14.00
	


— "-
25.70
__

222.00
146.00
63.10

119.00 609.00 , 48.50
152.00 31.50 25.20
34.20 24.00 29.20
9.98 — 10.60



21.90 18.50
38.20 21.50 11.00


199.00 395.00 1240.00
72.20 189.00 188.00
—

45.20
76.30
43.70
16.40



25.60
16.90


710.00
128.00

    Errors are less than 20% except:
        a -error between 20% and 100%
        b -error greater than 100%
        c -suspect, omitted from average
    * Table from reference 2.

-------
                          ;                        Table.7.2
                  Plutonium in Three-to Six-Kilometer-(2-to 4-Miles-)Distant  Ambient Air
Number of -
Station Samples Taken
S-31
S-32
S-33
S-34
S-35
S-36
S-37
S-38
S-39
S-40
S-41 -,.-'-
S-42
S-43
S-44
Summary
12
12
12
3
3
2
12
10
12
12
12
12 ;
11
'12
137
Less Than
Detectable
1
' "•• V '• 1
1
1
0
0
0
0
1
0
, . . 1
: i .,;
• - ••• i' .• ',
. ' .- i- - -;
•=• - g ~
Volume
(cubic meters)
461,547.0
543,346.0
531,886.0
118,243.0
119,322.0
57,286.0
525,181.0
460,089.0
5,02,129.0
486,876.0
472,698.0
416,244.0
360,818.0
429,709.0
5,485,374.0
Concentration (xlO~ yCi/ml)
C C a
maximum
0.144
0.134
0.097
0.176
0.116
0.012
0.198
0.097
0.102,.
0.198
0.136
0.137
0.185
0.094
0.198
average
<0.032 ± 96%
<0.035 ± 96%
<0.034 ± 95%
<0.037 ± 550%
0.027 ± 538%
0.012 ± 1734%
0.056 ± 93%
0.027 ± 108%
<0.026 ± 97%
0.054 ± 92%
<0.033 ± 99%
<0.037 ± 96%
<0.056 ± 105% t
<0.029 ± 103%
—
Volume-Weighted Average

a.  Volume-weighted average.
*  Table from reference 9".
                                                                                       <0.037 ±  29%
                                                                                                            w

-------
                                    37
                                 Table 7.3

             Annual Dose  Rate  to Various Lung Compartments from
            Chronic Exposure to Plutonium and Americium Aerosols

(Concentration »  1  fCi/m  and  Particle AMAD - 0.05, 1.0, and 5.0 micrometers)
                               Plutonium-239
Duration of
Exposure
years
1
5
10
70
Duration of
Exposure
years
70
Pulmonary
mrad/yr x 10
O.OSv l.Ov 5. On
Tracheo bronchial
mrad/yr. x 10
0.05p l.Ov 5. On
3.9 1.5 .7 2.7 1.1 6.1
9.1 3.5 1.7 3.7 1.5 7.9
9.8 3.8 1.8 3.8 1.6 8.1
9.9 3.8 1.8 3.8 1.6 8.1
Americium-241
Pulmonary -
mrad/yr x 10
6.5v l.Ov 5.0v
10. 4;2 1.9

Nasopharyngeal
mrad/yr x 10~
0.05u l.Ou 5.0u
.04 11. 30.
.04 11. 30.
.04 11. 30.
.04 11. 30.
                                  256

-------
                      38
                   Table  7.4          ..-...,

Annual Dose Rates to Various Organs from Chronic
   Exposure to  Plutonium-239 and Americium-241
    Aerosols AMAD=ly; Concentration 1 fCi/m3
Duraction of
Exposure
(years) Liver
1.
5
10
15
20
30
40
50
70
.001
.018
.052
.089
.13
.19
.24
.29
.36
Pu-239
(mr ad /year)
Bone T-B Lymph
Nodes
.0005
.0065
.019
.034
.049
.078
.11
.13
.17
.40
4.0
7.0
8.7
9.8
12
14
15
19
Am-241
(millirad/year)
Liver Bone
.0015
.019
.055
.095
.13
.20
.26
.30
.37
.0005
.007
.021
.036
.052
.082
.11
.14
•18
T-B Lymph
Nodes
.39
4.2
7.4
9.1
10
12
14
16 '
20
                    257,

-------
                                                            Table 7.5
ro
Sample
RF 1A


RF IB


RF 1C


RF 2A

Tamura


Size Increment (ym)
2000-105
105-10
<10
2000-105
105-10
<10
2000-105
105-10
<10
2000-105
105-10
2000-105*
105-10
<10
Wgt. Fract.
.62
.18
.20
.63
.17
.20
.64
.16
.20
.46
.34
.20
.47
.42
.11
Act. Fract.
.07
.40
.53
.39
.06
.55
.43
.07
.49
.13
.37
.50
.11
.61
.28
gi
.12
2.21
2.65
.63
.34
2.74
.68
.46
2.47
.28
1.10
2.48
.23
1.45
2.54
£ i i
i i

.7
.3 2.34
_,
.7
.3 1.06
_
.7
.3 1.06
•v '•'
w
.3 1.51 «>
av. 1.49
_
.7
.3 1.78
     *Data only for untreated samples and normalized to particle sizes less than 2000 ym.
                                                                                               Overall Average  1.63

-------
                                         40

                                      Table  7.6*

                   Plutonium and Americium in Public Water Supplies
Reservoirs
Number of
Samples Taken
Great Western
Great Western3
Standley Lake
Summary
Finished Water
Arvada
Boulder
Broomfield
a
Broomfield
Denver
Golden
Lafayette
Louisville
Thornton
Westminster
Summary
Average

Reservoirs
Great Western
Standley Lake
Summary
Finished Water
Arvada
Boulder
Broomfield
Denver
Golden
Lafayette
Louisville
Thornton
Westminster
Summary
Average
36 /
36
72
11
12
39
11
11
12
11 ;
12
36
155 .
Number of
Samples Taken
38 .
37
75
11
11
37
11
11
12 .;
12
12
39
156
Plutonium
c
minimum
<0.013
.046 -«
<0.013
<0.013
<0.005 "
<0.005
<0.013

<0.005
<0.005
<0.005
<0.005
<0.005
<0.013
,<0.005
-
Americium
c
minimum
0.014
<0.013
<0.013
,<0.001 ,..
<0.001
<0.023
<0.001
<0.001
<0.001
<0.001
<0.001
<0.013
<0.001
Goncentration (x
c
maximum
0.952
': .214 !
0.142
0.952
o:.6i9
0.014
0.133
.038
0.016
0.048
0.030
0.012
0.018
0.210
1 ; 0^210:
" —
10 • yd/ml)
C b
average
<0,.099 ± 58%

<0.036 ± 23%
—
<0.006 ± 50%
<0.007 ± 17%
<0.041 ± 26%

<0.008 ± 29%
<0.009 ±107%
<0.007 ± 67%
<0.006 ± 21%
<0.009 ± 32%
<0.041 ± 31%
-
<0.027 i 49%
—9
Concentration (x 10 yCi/ml)
c
maximum
<0.090
<0.090
<0.090
'.- "" - ." . - -*'"- - ;- >
.„..-. 0.239
-.' 0.015
0.150
0.420
0.044
0.030
0.400
0.007
0.079
0.420
C b
average
<0.033 ± 20%
<0.027 ± 19%
—
<0.026 ± 180%
<0.006 ± 180%
<0.029 ± 31%
<0.043 ± 196%
<0.009 + 80%
<0.007 ± 67%
<0.039 ± 185%
<0.005 ±3%
<0.029 ± 18%
-
                                                                 <0.032 ± 25%
*  Table from reference 9 .
a. Data of Poet and Martell  (1970);
b. Sample-weighted average

-------
                                   41
                                Table 7.7

              Fraction of Ingestion Material Transferred  to
                  Blood from the Gastrointestinal  Tract
Radionuclide

Plutonium-238

Plutonium-239

Plutonium-240

Plutonium-241

Americium-241

Curium-244
Transfer Fraction
non-oxide    oxide
  10
    -3
  10
    -3
  10
    -3
  10
    -3
  10
    -3
  10
    -3
10
  -3
10
  ,r4
10
  -4
10
  -3
10
  -3
10
  -3
                 Biologically
                 Incorporated
5x10
    -3
5x10
    -3
5x10
    -3
5x10
    —3
5x10
    ,-3
5x10
    -3
                               .26P
               u

-------
                             42
                           Table 7.8

          Annual Dose Rate Due to Chronic Ingestion of
Plutonium-239 Oxide, Americium-241, Plutonium-241 and Curium-224
                   Annual Intake 1000 pCi/Year
Duration of Plutonium-239 Oxide
Inges'tion (yrad/year)
Years Pone Liver Whole
Body

1
5
10
15

20

30

40

50

70

0.9
4.3
8.4
1.2X101
1
1.6x10
i
2.4xlOx
1
3.0x10
i
3.7x10
i
4.8X1Q-1

2.4
1.2X101
2.2X101
3.2X101
: I
4.1X10-1
i
s.exio-1
,1
6.9x10
1
S.lxKT
i
9.8x10
_•}
4.6x10 J
2.7xlO~2
4.5xlO~2
6.6xlO~2
»
8.6x10
•i
1.3x10 •
_i
1.6x10,
_1
1.9x10 •"•
_i
2.6x10
Americium-241
(yrad/year) .
Bone Liver Whole
Body

9.2
4.5X101
S.SxlO1
1.3xl62
2
1.7x10
0
2.4x10
2
3.1x10
2
3.8x10 '
0
4.9xlOz
1
2.5x10
1.2xl02
2.3xl02
3.4xl02
2
4.3x10
"}
5.9x10^
2
7.2x10
2
8.3x10^
2
9.9x10
_2
4.9x10
2.4X10"1
4.7X10'1
6.9X10"1
i
9.0x10

1.3

1.7

2.0

2.6

-------
                                   43
                                Table 7.9

       Food Ingestion Rates and Radionuclide Discrimination Ratios
Substance
Leafy Vegetables
Other Vegetables
Cow Milk
Beef Muscle
 Beef Liver
 Soil (casual)
 Soil (deliberate)
Ingestion Rate(g/day)
         270
         740C
                              436
         273
                               13
          .01
           20
                             Pu
                                                  Am
                                                  Pu
                                                  Am
                             Pu
  Discrimination Ratio

Pu(ext.)   [10

Pu(int.)    10"

Am(ext.)

Am(int.)

Pu(ext.)

Pu(int.)

Am(ext.)

Am(int.)    ;5xlO~
                                                              5x10"
                                                              10
            3.17x10"

            3.17x10"

            3.29x10"
                                         3.29xlO
                                                              2.0xlO
                                                                    ~3
Am
Pu
Am
Pu
Am
2.0x10
1.0
1.0
1.0
1.0
 a.  from ref.  25.
 b.  assumes vegetation is 70% water
 c.  assumes retention and transport within cow is  the same  for Pu and Am
                                262

-------


Ingestion


Substance , Radionuclide
Brisking Water Pu
Am •.. •
Leafy Vegetables Pu (ext.)
Py (int.,)
Am; (ext.)
'•,.." Am (int.)
Other Vegetables Pu,,(ext.)
Pu (int.)
Am (ext.)
Am (int.)
Cow Milk Pu
Am
Beef Muscle Pu
Am
Beef Liver Pu
Am '' "
Soil (casual) Pu "
Am
(deliberate) Pu
" , : 	 ." '• ,. /Am ••-••••

" 	 44
Table 7.10
and Resultant Bone Dose Rates
,,:•-_-•:
• - " • • • •' •;.
Ingestion Rates (p Ci/yr)
18
13
297
3
53
27
82
9
15
74
1.6xlO~3
.28xlO~3
1.02
l.SSxlO"1
2.96
5.33X10"1 ..-:.
18.0
	 3.2 	 ' , . ..
3.24xl04
'.'- 5.84xl03
Total
2 £3



70tlfl Year Bone
Dose Rate ,
(inrad/yr)
8.8xlO~3
6.2X10"73
.014
.071
.026
.067
.004
.020..
.007
,018
.40xlO~5
.67xlO~6
2.5xlO"3
.2.8xlO~4
7.1xlO~3
1. 28xlO~ 3
8.6xlO~4
1.6xlO~3
.44
'"'.;; 26"
0.653


-------
                                 45
                                Reference
1.   Proposed Guidance on Dose Limits for Persons Exposed to Trans-
     uranium Elements in the General Environment, USEPA, Washington,
     B.C.  (September 1977).

2.   H. Volchok, M. Schonberg, and L. Toonkel, Pu-239 Concentration in
     Air Near Rocky Flats. Colorado, HASL-315, Health and Safety Laboratory,
     USERDA (1977).

3.   P. W. Krey and E. P. Hardy, Plutonium in Soil Around the Rocky Flats
     Plant, HASL-235, Health and Safety Laboratory, USERDA  (1970).

4.   Task Group on Lung Dynamics, Health Physics, 12, p!73  (1966).

5.   H. Volchok, R. Knuth, and M. Kleinman, "The Respirable Fraction of
     Plutonium at Rocky Flats," Health Physics, 23, p395 (1972).

6.   G. A. Sehmel, Airborne 238Pu and 239Pu Associated with the Larger
     than Respirable Resuspended Particles at Rocky Flats During July 1973,
     BNWL-2119, Battelle Pacific Northwest Laboratories  (1976).

7.   R.E. Sullivan, Plutonium Air Inhalation Dose  (PAID), ORP/CSD-77-4,
     USEPA (1977).

8.   P. Krey et al., Plutonium and Americium Contamination  in Rocky
     Flats Soil. 1973. HASL-304, Health and Safety Laboratory, USERDA
     (1976).

9.   Environmental Monitoring at Major USERDA Contractor Sites - Cy
     1975, ERDA-76-104, Vol. 1, USERDA, Washington, D.C. (1976).

10.  L. R. Anspaugh, L. H.  Shinn, P. L. Phelps, and N.  C. Kennedy,
     "Resuspension and Redistribution of Plutonium in Soils," Health
     Physics. .29_, p571  (1975).

11.  L. R. Anspaugh, !'The Use of NTS Data and Experience to Predict Air
     Concentrations of Plutonium Due to Resuspension on the Enewetak
     Atoll," The Dynamics of Plutonium in Desert Environment, NVO-142,
     p299  (1974).

12.  D. E. Bernhardt, "Resuspension of Plutonium;  It's  Particle Size
     Distribution  in Soil," in Evaluation of  Sampling and Collection
     Techniques for Environmental Plutonium,  ORP/LV765,  USEPA  (1976).

13.  T. Tamura, "Effect  of  Pretreatment on  Size Distribution of Plutonium
     in Surface Soil from Rocy Flats, in Transuranics in Desert Ecosystems,
     NVO-181, p. 173  (1977).

14.  T. Tamura, "Physical and Chemical Characteristics  of Plutonium in
     Existing Contaminated  Soils and Sediments," in Proceedings of  the
     International Symposium  on Transuranium  Nuclides in the Environment
      (NOV. 1975),  IAEA,  Vienna.

-------
                                   46
15.  C. J. Johnson, R. R. Tidball and R. C. Severson, "Plutonium Hazard
     in Respirable Dust on the Surface of Soil," Science, 193, p488
     (1976).                                      :  ~.

16.  W. S. Chepil, "Sedimentary Chacteristics of Dust Storms:  III
     Composition of Suspended Dust," Am. J. Sci., 225, p206  (1957).

17.  W. G. Slinn, "Dry Deposition and Resuspension of Aerosol: Particles -
     A New Look at Some Old Problems," in Atmospheric-Surface Exchange
     of Particulate and Gaseous Pollutants, CONF 740-921, ERDA, Washington,
     D.C. (1974).

18.  K. Willeke, K. Whitby, W. Clark, and V. Mayle," Size Distribution
     of Denver Aerosols - A Comparison of Two Sites," Atm. Env.9 j^, p609
     (1974).                                                        '

19.  J. W. Healy, A Proposed Interim Standard for Plutonium in Soil, LA
     5483-MS, Los Alamos Scientific Laboratory (1974)..

20.  R. C. Milham, J. F. Schubert, J. R. Watts, A. L, Boni, and J. C.
  >   Corey, "Measured Plutonium Resuspension and Resulting Dose from
     Agricultural Operations on an Old Field at the Savannah River, Plant
     in the Southeastern U.S.," in Proceedings of the International'
     Symposium on Transuranium Nuclides in the Environment,  (Nov. 1975),
     IAEA, Vienna.,

21.  D. R. Rogers, Mound Laboratory Environmental Plutonium Study 1974,
     MLM-2249, Mound Laboratory. (1975).                         -

22.  J. S. Jones and S. F. Pond, "Some Experiments to Determine the
     Resuspension Factor of Plutonium from Various Surfaces," Surface
     Contamination, B. R.  Fish (ed.), Pergamon Press, New York, N.Y;
     (1964), p83.

23.  S. E. Poet and E. A. Martell, "Plutonium-239 and Americium-241
     Contamination in the Denver Area," Health Physics, - 23, p537 (1972).

24.  R. P. Larsen and R. D. Oldham, "Plutonium in Drinking Water: Effects
     of Chlorination on its Maximum Permissable Concentration," Sci.,
     201, p. 1008 (1978).

25.  W. E. Martin and S. G. Bloom, "Plutonium Transport and Dose Estimation
     Model," in Proceedings of the International Symposium on Transuranium
     Nuclides in the Environment, (Nov.r 1975), IAEA, Vienna.       .     ..,  .

26.  D. E. Bernhardt, and G. G. Eadie, .Parameters for Estimating the
     Uptake of Transuranic Elements by Terrestrial Plants, ORP/LV-76-2,
     USEPA (1976)	                ,          •.-.-.-...

27.  R. L. Thomas and J. W. Healy, An Appraisal of Available Informa-
     tion on Uptake by Plants of Transplutonium Elements and Neptunium,
     LA-6460-MS, Los Alamos Scientific Laboratory (1976).'

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28.  R. A. Bulman,  Concentration of Actinides in the Food Chain, NEPB-
     R44, Harwell (1976).

29.  J. ¥. Healy, An Examination of the Pathways from Soil to Man for
     Plutonium,  LA-6741-MS,  Los Alamos Scientific Laboratory (1977).
                                  266

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     8.    DISCUSSION OF COMMENTS SUBMITTED BY CARL JOHNSON,  M.D.,
              DIRECTOR OF HEALTH,  JEFFERSON COUNTY, COLORADO

 8.1   Introduction  •

      Dr.  Carl Johnson has,  during the last several years,  proposed and
 strongly  advocated use of a soil  sampling and analysis procedure  which
 supposedly gives  a better indication of the inhalation hazard to
 persons in the vicinity of  environmental transuranium element
 contamination then other commonly used methods.

      The  method proposed by Dr. Johnson requires  collection of the
 loose surface soils with a  broom  and dustpan,  followed by  a size
 separation procedure,  and retention  of only that  fraction  of all
 particles with mass less than  that equivalent to  a 5  micrometer sphere
 of Pu02.   Results  are  reported in terms of activity per gram of the
 material  analyzed.

      Dr.  Johnson has also published  and widely diseminated  certain
 other conclusions  related to the  health risk as derived from these
 measurements.   A copy  of a  paper  prepared by Dr.  Johnson, which
 summarizes most of  his pertinent  views,  is appended.   The  staff of the
 Office of Radiation Programs has  reviewed these submittals  and its
 conclusions  are presented in this  section.

 8.2   Applicability  of  Soil  Sampling  Methods

      The  usefulness  of any  soil sampling method to indicate  the
 potential  inhalation hazard to  individuals is  questionable because the
 correlation  of  air  and soil concentration must be  made  by
 calculational models which  require certain specific information
 applicable to  the particular site.   The  limited accuracy, precision,
 and reproduciblity  of  environmental  measurements necessarily
 introduces some uncertainty into  such  calculations.  The relationship
 of a  soil  concentration  per  unit  area  to an air concentration  per  unit
 volume is  generally  given by a resuspension factor, defined as

      RF =  air concentration/m-*
           soil  concentration/m^

      Observed values of  the  resuspension factor for environmental
 contamination existing for more than a few years are generally between
 10~9  and lO"11^.  However,   before a resuspension  factor can be
 applied to a  site, it must be derived from a statistically significant
 number of measurements, for  that specific  site.  This may be difficult
because soil concentrations   can vary greatly from  sampling location to
 sampling locations, and only a fraction  of  the particulate content of
 the air is derived from the  soils in the  immediate vicinity of  the
 sampling location.
                                        267

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     More general methods based on the mass loading of suspended
particulates in air, usually derived on a regional basis, have also
been suggested and appear to give a much better indication of the time
averaged air concentration at a specific location.  However, in all
cases it must be recognized that soil concentration measurements are a
secondary method for estimating airborne particulate concentrations
and their success is directly related to the amount and quality of
data available to make the proper conversion.

     Despite the difficulties noted above, Dr. Johnson has chosen to
use soil concentration data as the primary index  for evaluating
potential inhalation exposures.  Therefore, the questions which must
be addressed are whether  the proposed sampling and  analysis  technique
has general validity, how it compares to other methods, what the
significance of  the differences represents in  terms of public health
protection, and whether Dr. Johnson uses his data correctly  in
determining the  inhalation hazard  to  individuals.  These  points will
be considered  in  turn.

8.3   Inhalation Hazard

      The inhalation hazard  of  airborne  particulates is  directly
related to  the concentration of particles  in  the  air  near ground
level.   The mechanism of  transport to the  different compartments  of
the  respiratory  system,  deposition,  and retention has been extensively
studied. The  Task Group  on Lung  Dynamics  of  the  International
Commission  on  Radiological  Protection published a report (J. Health
Physics, Vol.12,  pp.  173-207,  1966)  which specifically considered lung
 deposition  and retention in terms of an activity median aerodynamic
 diameter (AMAD)  of particles  as a basis for lung dosimetry.   These
models require knowledge of the amount of radioactivity associated
with all sizes of airborne particles, and not of only a selected
 fraction.  Both the concentration and particle size distribution in
 air are best determined by air sampling devices  specifically designed
 for that purpose.  These data then provide the input for calculation
 of the inhalation dose rate to persons and evaluation of the potential
 inhalation hazard.

      The sampling and analysis method proposed by Dr. Johnson does not
 accurately measure the entire spectrum of particle sizes as actually
 found  in the environment by including only a portion of all particles
 in the reported results.  Therefore, the distribution as derived by
 Dr. Johnson's method does not provide all the data required as input
 by the mathematical models for dose  calculation  to the lung.  The
 results from  the method  proposed by Dr. Johnson  therefore cannot be
 used for the  evaluation  of an inhalation hazard  by the standard
 methods.
                                          :08

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8.4  Effect of Analysis-Procedure onParticle Size Distribution

     The chemical analysis procedure proposed by Dr. Johnson  is
designed to alter the size distribution of the samples collected in
the environment.  It achieves this result by subjecting  the soil
particles to various chemical and physical dispersion methods which
break down the bonding forces which hold the microaggregates
together.  The peroxide treatment removes the'organic matter which
serves as a binding component, and the ultrasonic treatment separates
and disperses the particles.  As a result, the distribution after
treatment tends to have many more particles in the smaller size range.
and therefore to indicate a larger fraction of the total plutonium to
be associated with particles in the "respirable size" range.

     The effect of the treatment used by Dr. Johnson differs with the
type of soil.  For the soils in the vicinity of the Rocky Flats Plant,
it has been shown (Tamura in Transuranics in Desert Ecosystems, Report
of the Nevada -Applied Ecology Group, U.S. Dept. of Energy, NVO-181,
Nov. 1977) that the dispersive treatment reduced the particle size
from an initial distribution where less than ,60% of the activity was
associated with the "respirable range" of-particles to a point where
more than 90%; of the.activity was in that range.  The activity median
aerodynamic diameter was changed,from 43 um for the untreated soil to
1.6 um for the hydrogen peroxide treated - ultrasonically dispersed
soil.

    'It must be concluded that the analysis method used by Dr. Johnson
drastically alters the size distribution of the soil samples and does
not accurately reflect the fraction of radioactivity associated with ,
soil particles in the "respi_rable size" range.

8.5  Particle Sizes and Inhalation • "•--.

     The method proposed by Dr. Johnson involves measurement of
particle size by a standard water-sedimentation technique commonly
used by soil scientists.  The diameter determined by this technique is
referred to as the Stokes diameter, and is derived from the settling
velocity and density.,  However, it is the aerodynamic diameter (Da)
rather than the Stokes diameter (Ds) which is generally used in
models which have been developed to describe the deposition and
retention of inhaled particles in the evaluation of an inhalation
hazard.  This aerodynamic diameter-, defined as the diameter of a unit
density sphere having the same terminal velocity as the particle lii
question,, takes into account the variable linear dimensions, density,
and aerodynamic drag factors which may vary considerably from particle
to particle.  The Task Group on Lung Dynamics of the International
Commission on Radiological Protection has recommended use of the
aerodynamic diameter in assessing inhalation hazards.
                                      oro

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     For the same terminal velocity of a particle, the Stokes diameter
and the aerodynamic diameter can be related by         •

         /PDS = Da

that is, the aerodynamic diameter is larger than the Stokes diameter
by a factor equivalent to the square root of the density.  For PuC>2
particle with a density of 11.4g/cm3, this factor is 3.4.

     Therefore, the 5 um particle as measured by water sedimentation
referred to by Dr. Johnson actually is a particle with a 16.9 um
aerodynamic diameter.  Because particles with aerodynamic diameters
exceeding 10 um are completely removed from the incoming air as it
passes through the nose, and do not penetrate to the lung, the
proposed method may greatly overestimate the respirable component of
soils.

8.6  Comparison of Results Obtained by Different Methods

     Significant differences exist in results of measurements of soil
concentration for the same area when reported by Dr. Johnson as
compared to results obtained by other methods, and it is important to
recognize the reason for these differences.  It is reasonably well
established that most environmental contamination by transurium
elements, whether derived from fallout or more localized sources, is
associated primarily with the smaller soil particles near the
surface.  Therefore, all methods - including the method proposed by
Dr. Johnson - will give approximately the same results when these are
reported in terms of activity per unit area.  Significant differences
are, however, introduced when the results are reported in terms of
activity per unit weight or mass because the basis for comparison then
is a function of the specific sampling procedure.  Methods which
collect a greater amount of soil per unit of surface area, such as
those which include all material to a given depth, then will give a
smaller activity per unit weight (e.g. curies per gram) than those
which limit the amount of soil included in  the analysis by either
sampling to a smaller depth or by eliminating a portion of the entire
sample by size fractionation.  Because of the much higher activity to
mass ratio in the size fraction sampled by Dr. Johnson, that method
will generally give higher numerical results.  It is important that
the reasons for1 these differences be understood and  should be noted
that these differences do not represent real differences in the
environment.  It  is very important,  therefore, that  the exact method
used be specified and to recognize that the results  obtained by
different methods cannot be used interchangably.
                                       270

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 8.7   Dust  Inhalation and Lung Dose                          •        --

      A large portion of Dr.  Johnson's  discussion is  directed toward
 the  probability  of  inhaling  a plutonium particle.  The issue,  however,
 is what is the dose/effect of that particle when it  is inhaled —  -.
 regardless of the probability of  inhaling it.                ,

       Dr.  Johnson erroneously assumes  that a resuspended 5  um  particle
 will  consist solely of  PuC>2  and proceeds to calculate  the mass and
 activity of this particle based upon the specific  activity  and density
 of Pu02*   Dr. Johnson's assumption will  considerably overestimate
 the  activity associated with a particle  of a given size,  because most ,
 resuspended particles consist of  a large soil  particle with a  smaller
 plutonium  particle  associated with it.   Hayden (in "Atmosphere -
 Surface Exchange of Particulate and Gaseous Pollutants",  ERDA
 CONF-740921,  1974)  measured  the sizes  of plutonium particles
 associated with  soil particles at  Rocky  Flats  and  found the Pu(>2
 particles  to  have a median diameter of approximately 0.08 um.   This  is
 consistent with  a report by  Little and Whicker (Journal of  Health
 Physics, Vol. 34, pp. 451-7,  May  1978) which states  that  the
 contaminated  oil at Rocky Flats was reportedly drained through 2-3  um
 filters  before placement into barrels.

     Dr. Johnson greatly overestimates the amount  of soil inhaled,
 when he  states that an  individual may  inhale and retain as  much  as  10
 to 12  grams  of dust in  the lung over the  course of a few  months.
 Airborne particulate mass loadings  at rural  sites, as  reported by the
 National Air  Surveillance Network  average on an annual  basis between ,
 10 to  50 ug/m3.  The amount  of dust inhaled  by an  individual can be
 calculated from this mass loading.  For  an assumed.dust leading  of
 50 ug/m3 (the average for Colorado  is much lower)  and  a.breathing
 rate of  20 m3/day,  less  than  0.4 g/yr would  be inhaled  by a person
 living near Rocky Flats.

     Krey  (CONF-740921,  ibid)  has measured the activity per  gram of
 respirable  dust in  the vicinity of  Rocky  Flats  and found  the
 concentration to be approximately 5 dpm/g.   Based  upon  a  0.4 g/yr
 inhalation  rate,  an individual would therefore  inhale  2 dpm  each year
 or 0.9 pCi/yr.  It  can be shown that continuous inhalation  of
 19 pCi/yr  inhaled continuously for  70 years  is  equivalent to a
 pulmonary  dose rate of  1 mrad/yr (Proposed Guidance  on Dose Limits for
Persons Exposed to  Transuranium Elements  in  the General Environment,
EPA-520/4-77-016).  Therefore, the maximum dose rate to .an  individual
 in the area of the Rocky Flats Plant as calculated by this method
would be only about 0.05 uCi/year.  This  calculated  dose  rate  is lower
than the Guidance recommendation limit of  1.0  millirad per  year  by
approximately a factor of twenty .
                                     271

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8.8 "Distribution" Factor

     The Environmental Protection Agency has recognized deficiencies
in how most sampling methods are used to evaluate the contribution of
the smaller particles in the soil to the inhalation hazard, and has
developed a method which considers the ratio of activity to mass in
different particle size ranges (termed "enrichment" or "distribution"
factor).  It is intended to both minimize the number of analyses
required and provide a maximum of useful information.  The method
requires a detailed analysis of a small number of representative soil
samples from a given location, the results of which can then.be
applied to all samples taken from that area.  Most analyses can then
be performed on soil samples including all size fractions  (generally
all particles smaller than 2 millimeters - the definition  of  agronomic
soil) while site-specific information can be derived on the
composition of the resuspended portion.  The method is intended to be
used with the mass loading calculational procedure for deriving the
corresponding air concentration, rather than with the resuspension
method which already includes  the correction term in the experimental
data.  In effect, the "enrichment" or "distribution" factor converts
the average radioactivity to mass radio for  the entire soil sample  to
the radioactivity to mass ratio of only the  resuspended fraction.
Details of  the method are described  in EPA document 520/4-77-016
entitled "Proposed Guidance  on Dose  Limits for Person Exposed to
Transuranium Elements in the General Environment."

8.9  Conclusion

     In  summary,  the U.  S. Environmental  Protection Agency does  not
 recommend  that  soil  sampling and  analysis methods be used  as  the
 primary means  of  implementing  requirements which  specify  inhalation
 dose  limits  to members  of the  general  population.   Such methods  suffer
 from the  inherent problem of relating  the soil  and  air  concentrations
 of the contamination and,  at best,  can only  serve  as  a  useful
 indicator  or  screening  tool.   The results obtained  by  the  different
methods  for soil  sampling and  analysis are not  generally  comparable,
 and must be specified in terms of the  procedures  used.

     Any of the commonly used, or proposed,  soil  sampling and analysis
 methods can be utilized for evaluation studies and provide useful
 data.   Application to implementation of public health protection
 criteria of any soil sampling method is limited by the fact  that
 environmental pathway and transfer factors must be determined on a
 site-specific basis and validated with extensive experimental data.
 The usefulness and confidence one can place in the results obtained by
 any particular method is therefore directly related to the extent that
 the method furnishes reliable data useful for the estimation of
 adverse health impacts on individuals in the general population.
                                    212

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     In the view of the Agency staff, the method proposed by Dr.
Johnson does not satisfy technically acceptable criteria for adequate
evaluation of a potential health hazard to individuals or population
groups.  It does not provide the required data for calculation of lung
dose rates by methods recommended by the International Commission on
Radiological Protection, incorrectly classifies the sizes of particles
with respect to inhalation dynamics, and greatly overestimates the
intake of respirable dusts by an individual.   We therefore conclude
that the proposed method should not be used to assess the inhalation
hazard to individuals living in close proximity to environmental
contamination.
                                    273

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      EVALUATION OF THE HAZARD TO RESIDENTS Or AREAS CONTAMINATED WITH PLUTONIUM

      Carl J.  Johnson, M.D., Jefferson County Heolth Department and the University of Colorado School
                              of Medicine, Lakewood, Colorado 80226

                                                Abstract
      ptufonium oxide particles in fhs fine participate soi! fraction of surface cJust ore subject to suspension
by air currents and are a potsntiai health hazard to humans because of inhalation.  This respirabie paiijculafe
fraction has bean defined us the particles - 5pm.  The respirabie fraction of surface dust can be fepcrofeo
by ultrasonic dispersion and a standard wafer-sedimenfaHon procedure.  We'believe this rnelhod of evaluation
defines more precisely the potential health hazard  from plutoniufn-contaminoted soils then other methods.
With this method, pi uranium levels in ths  respirable-particulate fraction of offsife soils located downwind
from a plutoni'jrr.-processing plant (Rocky Flats) were found to be os much as 380 tiroes the background level.
Risk estimates for residents may be made by cciieolation of dosage .related to quantities of respirable dust
inholerl cnnua'iy.  For example, in residential areas with  20-disintegrations of p! uranium par minute per
gram of respirabie dust, or person may inhale  and retain 10 to 12 grams or mere'of resusoended d'ost (100
picocuries) ovar a period of months or years and may receive about 0.1 rem to fhs Sung, 4-5 rern fo rhe
frachio-bronchia!  lymph nodes, and 0.12 rem to the iiver. The gcnadal and 'eta! dose is difficult fo evaluate,
butp'ufoniom has be-.n found  in gonada' tissue and .in  the  fetus.  This amount of exposure fo one million
people cculd re$»H in cbput 160 excess deaths duo to leukemia and a  total  increase in ail  neoplasms of perhaps
} io 3 per cent over c period of 70 years.  This may include from 6 fo 1COO excess cases of bone ccncer (this
largts range  is due f» two point-; of view).  The incidence of all  genetic diseases may increase by ,1.5%
and ill health related ro chromosome mutation by 10%, for oil succeeding generations. Other factors,  such
as the ingrowth of Axericium, use of etiolating agents in fertilizers, eic. may change  the nature of the risk
and actually increase the  incidence of effects.  These considerations demonstrate a need for the establishment
of conservative Units or, psrmissabls soil contamination by piutoniurn  in reiidsnlia! areas.
                                             introduction
      Plutonium oxic's particles deposited on the ground surface by accidental spills or atmospheric fallout
(Table 1) ere. subject to resuspenston by wind or orher means.  Particles in the  size range of 5 jjrn end srndier
ore considered to be of rsspirabie  si;:e because when inhaled they may be retained v,;ihin  the^yng1'1-.  Most
of iho plufonium oxide particios released offsife by r.ucienr installations are in this size ranae^/'.  This paper
describes a method of measuring the concentration of plufoniurn in the potentially respirabie surface o'usr and
discusses thfe potential health effects cf exposure fo such dust.
                                   Sample  collection and processing
      In our tiudy crsa (downwind from rhe Rocky i:T«Tj^plant) sirss for sampling wer«» selected foilowing  '•
guidelines propowd by the Atomic Energy Commission^'1.  A composite sample of the loose, su.-ficic,-!  (about
0-0.5 cm dsep) soii i~o.old lettiing velocity v/os computed from Stake's eqtiaiicn using an effective  dinmstcr
                                        274

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 i»f 5 pfh and a density of 11.36 g/cnv* (plutonium -oxide).  The size fracfion-thus collected includes other
 mineral  parades with equivalent settling velocities that have some combination of smaller density and
 forger diameter. The collected fraction was freeze-dried and anaiyred for plutonium by radiocheir.ical
 procedures'''/^/.  Contamination of off site soils in the study area (an area proposed for residential develop-
 ment) was found to be as great as 330 times the background value.  We believe that the concentration of
 pfutomurn in the respircble fraction of surface dust, as defined here, is an index that can be more readily
 related to the  potential  health hazard than other indices utilized for this purpose.     ,  '    •      I
  ' "  •                          -•..--.-   Particle  Size and Activity                          •  •  ,.  •
      Relationships between particle size, volume, mass and radioactivity :are shown in Table 2.  A particle
 of plutonium oxide one pm in diameter weighs about six millionths of a mierogram '(j.>g). This particle is " '
 very small but has an activity of 0.3 picocuries (pCi) or about one disintegration every i .5 minutes.  A    •
 particle S.yrn in size has'a mass of .007 pg.   This particle is also of respiroble size and will have an activity
 of about 4.1 pCi or some 90 disintegrations per minute (dpm). One hundred of the 5 pm particles together  •
 would weigh about 0.07 pg.  Since plutonium has a biological activity 15 or more fimes as great as radium,
 this mony particles of plutonium oxide may be similar in effect to 0.5 yg of radium,  the smallest bone -doss
 found associated with osfeosarccma in radium dial pamrefsv'. Although plutonium may be present in con-
 taminated crsas offsife in  extremely small quantities, this may be sufficient to produce bone cancer and
 other iypes of  rumors.
           ,-                         Estimates of Dosage end Effect                         ...        •
      The recommended dose limit of plutonium 239~(occupatidnal exposure)-to lung is at present  15 rem/yecr
 or 16,000 p.Gi. 'This maximum permissable annual dose (MPAD) is equivalent to about 400 five urn particles,
 or a totol moss of about 0.3 jjg of plutonium oxide. A single particle of  plutonium oxide 40 pm in size has
 more than this much. activity and is within the range of atmospheric dust (0.3 to 100 pm).  A particle of this
 sire might not be retained in the respiratory tract, but could lodge in an abrasion or other wound.
      Meyers gives evidence to support a recommendation that- a much mere realistic limit than the present  :
 1.5 rern  MPAD  for lung burden is the "maximum perrnissable pulmonary Lymph node burden" which  is placed
 at 230 pCiOC).  The maximum !ung level that cou'd produce this is 67 pCi.   Meyers points out that (his is
 less than 0.5% of the currently accepted MPAD (occupational) of 15 rems for the lung. The inhalation and
 retention of two 5 pm particles annually would exceed this amount.  Morgan  also demonstrates the? the
 present limit for exposure  to plutonium may be too high by a  factor of 240 or more, in* relation to potential  '
 effeuis on bcne'' '.'.  Again, two of the 5 pm particles would exceed this more conservative dose  limiti
      .The relative risk of  inhaling and retaining plufonium oxide particles in reference to the amount-of
 pJutonium in the respirable dust is illustrated in Table. 3. A  single.4 pm particle may produce about 50 a'pm,
 equivalent to about 20 millirems.  One such particle in 25 grans of respirable dust will produce an average
 activity of 2 dpm/gram of dust.  If g person hos inhaled and  retained 12:5 grams of dost, he has a 50% chance
 of inhaling that one 5 pm  particle of piufonium'oxide.  However, the particle may be in the first bit of dus^
 inhctied  or in the last bit.   The probability is one  in 1CO, expressed -in -the table as p=.01, that .?f 'he -inhales
 only 1/4 gram, that he'ruuv inhale rha 5 prrrpciticle.  Retenricn of two of these particles., or an eqyivolenf
 lorger number of smaller onrticiGs/wo^iQ exceed dose limiti propose.d by Morsaiicnci Meyers. It may be
 that in  the very first whiff of d'jst (25 milligrams) that he may inhule the  particle.. The chances are about
 one in one thousand that this could occur,  in -a total 'population, of 100,000 or more who could be housed  .
 in a contaminated area such as that near the Rocky F!afs plar.f, iheso od
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Incidence v/ou'd be 0.1% or one cose per thousand biifhs in ihe first generation, and 0.75% or about one
btrfh in 133 for succeeding generations.  The committee also believes that between 5% arid 50% of ill heal Hi
Is proportional to the mutation rate. This much radiation per generation cculd eventually lead to an  in-
crease of 5% in the ill health of the population.
      Estimates of excess rates of cancer may a'so be calculated  in the following manner, again referring
to an onaa with 20 dpm/g of plutonium in respirable dust.  The following example is the calculation of the
Increased rate of bone cancer in such a- contaminated area.
1 rom x one mil Men persons''3)  .  1000 pCi (infra1 ed)Q4) .  .   2.2 a'pm   .   1 gram  - 3.4 grams dust
10 excess bone cancer cases            3.2 rem (bone)          .1 pCi       20 dpm    1 excess bone cancer
                                                                                    per million persons
OFfsiro lands in our study area (downwind from the Rocky Flats plant) have levels far in excess of this amount,
and a development project five kilometers east of the plant site has  levels that approach 20 dpm/g in  respir-
aWe dust.  V/e see that about 3.4 grams of such dust (32 pCi), inhaled and  retained, may result in one
excess bone cancer case in a population of one million people over a life span.  Other effects from this
dbsoga of radiation rpoy be calculated  in a similar manner.  Such effects would be multiplied for each
cddStiofXi! 3-4 grams of respirable duel  in'r.alea'*.  Over a period of  months or years a person may inhale
and reiuin 10 fo 12 grams or more of rasuspsnded dust (100 pCi) an-J  may receive about 0,1 rem to the lung,
4-5 rem to the trachlo-bronchial lymph nodes, and 0.12 rem to the  liver.  Thw gcnadai end feral dose is
difficult to evaluate, "but plutonium has been found  in gonadal tissue and in the fetus.  This amount of
exposure to one million people could result in about 160 excess deaths due to leukemia ancl  o  tofai increase
In all neoplasms of perhaps 1 to  3 per cent over a period of 70 yeais''™.  This may include  from 6 to  1000
excess cases of bone cancer (this large  range is due  to two points of view).' '<• 'A.  The incidence of aii
genetic a'i<»asQS may increase by 1.5% and ill health related to chromosome mutation by  10%, for all
succeeding generations'  '. Other factors, such as the ingrowth of Americium, usa of chsiafing agents in
Fertilisers,, etc.  may change the nature of the risk and actually increase the incidence of offsets.  Because
plutonium is stored in the body to a considerable extent, a person living several yea's in such an area may
inhale and retain enough plutonium to produce these effects even though hs may 'nave ihs cre.a.
     •Effects are more likely to  occur Ir.  the fetus, the child, and in persons with increased susceptibility to
neoplasms. 'There  is evidence ihat smaller doses of radiation are  inora harmful per cad then would b<; expected.
Stewart and NecO end others have shown  a greater risk of leukemia per rod at low intrcuferine exposures,
0.25-0.5 rad, than at higher doses to the fetu.A'*'''.  One rem (equivalent to 25 5^m particles) may cause
an 80% increase in mortality from childhood cancers after fetal exposure, and a 0.9% increase in recognized
"spontaneous" abortions^3).
                                             Conclusion
      Federal guidelines are being promulgated bylhe U.S. Environmental  Protection Agency to guide the
use/ treatment., and lehabiiitctfon of land contaminated with plutoiiium. At the present rims there are areas
In the United States which  have  levels  of conrsminafion of 19 dpir/3 in respirable dust which are presently
being used or devsloped for residential  purposes'10). The imporfence of the esro-blishment of o maximum
allowable level of contamination based on the concentration of plutonium in the respirabie Just mt'it be
emphasired.  This level may be appropriately sef as low as 2 dpm/g, since there is sufficient evidsnca to
Indicate probable health effects  ar the  20 a'pm/g level, and possibly ar levels below this figure.
      As much as 67 mg of du«.t per cubjc meter (mg/m^ ) hcs been measured downwind from farm equipment.
     An average value of 0.1.75 mj/M° was observed in  Denver In 1970-73.  Average annual respirator)'
     volume is about 8000 m^ for an adult.
                                         -nr
                                          t b

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                                                              References
 1. Ar^?fion D.O.:  Chronic non!yberculous respiratory disease.  In Claik, D.W. and MqcrVahon, B. (Ed.) Preventive Medicine.  J. &
  •  A. Churchill Ltd.. London. K57.
     Eider,  J.C., Gonzole:,  M., and Etlinger, H.J.:  Plutonium ooroiol si?c characteristics.  Health Fhy;ics, 27: 45-53, July,  1974.
2.
3.

4.
5.
     Measurements o; radionuclic'rts in the environment, sampling o:id onp'ysis of plutonium in soil.  Stor.dards for protection against radiation:
     U.S. Energy R?s. Dev. Adm. Regulatory .Guide 4.5, 10 CR, part 20, Federal Register 20, p.  106, 1974.                            ,
    • Johnson, C. J.,  Tia'ba!!,  R.R., end Severson,  R.C.: Plutonium ha/ord in respiroble dust on the surface of soil . . Science/ 193: 48S-490,  }9~i
     Kunre,, G.W.: Prctreatmont for mineraloqical  analysis,  in  Block, C.A., atid others, ed., Methods of soil analysis, part 1:  Madison,
     Wis.f Amer. Soc; Agronomy, 563-577, 1965.
 6.  Day, P.R.: Particle fractionation and particle-size analysis, jn_ Block, C.A., and others, ed.. Methods of soil analysis, port 1:: Madison,
     Wisi, Amer. Soc. Agronomy, 563-577, 1965.                                                   "                  '
 7.  Tolvitie, N. A. : Rcdiochemical determination of plutonium in environmental and biological samples by ion exchange.  Anol. Chem.:
     43: 1827-1830,  1971.
 8.  _ __   : Electrcdeposition of acfinides for alpha spectrometric determination.  Ana' . Chem.: 44: 280-283,  1972.
 9.  Mortland, H.STond Humphries,, R.E.: Osteogenic sarcoma in dial painters using luminous paint. Arch. Path., 7:406,  1929.
10.  Meyers, D.S.: A plea for consistent lung burden criteria for insoluble alpha-emitting isotopes. U. of Col .,  Lawrence Livermore lab.
     Health Physics,  June, 1972.                                                                               .
11."  Morgan/- K.Z.:  Suggested reduction of permissoble exposure to plulonium and other transuranium e'emenfs. Am. Ind. Hyg. Ass.  J.:
     567-574, August,  1975.                                  '                    •                         :           .....-'...'...
12.  Anon.: The effects on populations of exposure to low levels of ionising radiation. , Report of the Advisory Committee on ihe Biolonical
     Effects of lonmng Radiations, Division of Medical Sciences, National Academy of Sciences. National  Research Council , Washington,
     D.C., 20005, November,  1972.                                  .
13.  Anon.: Approaches to population protection in the case of nuclear accidents.  (Unpub.) Office of  Radiation Programs, U.S. Environmental
     Protection Agency}.. Washington, D.C. 20460.                                                 *             '                       .  .
14.  Thompson, R.C.: Implications with respect to the Protection Criteria.  Plutonium and other Transuranium Elements: Source1:, environmental
     distribution and biomedical effects.  Publication \VASH  1359.  U.S. Atomic Energy Commission, December,, 1974.
15.  Stewart, A., Webb, J.,  and Hev.-ett,  D.:  A survey of childhood malignancies.  British Med. J., 1:1495, 1958.
16.  Johnson, C.J.:  Survey c* land  proposed, for residential development east of Rocky Flats, for plutonium 239 contamination of respirable dust
     on the  surface of the Soil, and proposal of a new standard to define the potential airborne- piutoriium"  particle hayard.in terms of concen- ,
     tration  of plutonium in respircble dusl. Report to Ihe Jefferson County Commissioners and the Colorado State Health Departnent. Un-r ,
     published.  September?.  1975.                                   :                         •   -
 17.  V/renn, M. E.: Environrr.entpl  levels of plutonium ond the transplutonium elements in plufonium and other transuranium elements:  Sources,
     environmental d'slribufion and bibmedical effects.  \VASH 1359.  U.S. Atomic Energy Commission,  December,  1974  (Testimony before
     on Environmental Protection Agency Hearing Board,  Washington,  D.C.).       •                                                    '
 IP.  Bennett, B.G.:  Environmental Pathways of Transyrcnic Ele-nents.  WASH  1359 (ibid.)                        '    •     •     .
 Acfenciv/ledgement:  Valuable assistance of R.R. Tidball, PH.D. ond RfC. Severson, Ph.D.  of the U.S. Geological  Survey in the design and
 ejcccution of the survey, end revitw of the report.                                                                  •....'"
                        . Table 1                                                         _  Table 2                             o
             ConcenSrptions of Plulonium in Soil                         Plufonium oxide particles: Volume in cubic micrometers ((Jrn")
                                                                      mass in  micrograms (HQ) and radioactivity of plufonium 239
                                     Disinlegrofions                   in  picocuries fpCi) and disintegrationtioer minute (dpm)
    Location                         per minute/gram                 ' by particle size .in pins, for sphere-shaped particles.
    Worldwide (fallout)                  0.0 to 0.4
    Control Now Mexico (Trinity)*       0.3 to 22.2
    Nevada Test Site *                   0.2 to 22.2
    Los Alamos Scientific Laboratory*     0.01 to 111
    Rocky Fiats*           '     -        0.4 to 211
    Bikini Atoll                         2.9 to 422
    Polomores                           0 to 3996
    EniweloU Atoll :"                    76 to 7104
         *Offsite    Adapted from Ref.  17

           :,   Toble3
    Relative risk of inhaling and retaining
    ptotonium particles,  by level of radioactivity
    of respirab|e dust end quantity of contam-
    inated dust inho'ed.

    Activity of    Assuming one particle,
    pfutonium irr  grams dust inhaled ond
    respiroble     retained to retain £3 c!pm*
    dusf          P--.S   o=.01   P7.W1_
Particle
SI 76 in j-fftl
40
5
4
2
1
Volume
pm-*
33,510
61
34
4.2
0.5
'.Mass
^g
'0.38
6.7X10"3
3.8x10"^
4.9xlO~5
. 6.1xl6"6
                                                               Table 4
                                                   Dose-equivalent in rem per 10CO-
                                                   picocuriss of plutonium 239 inhol
                                   Activity
                                pCi      dpm

                                21,000   46,000
                                   • 41       90
                                    21       46
                                   2.6      5.8
                                   0.3     .0.7
                                 Toble 5
                Estirmted rates of plutor.ium-ind'jced ccncer aid
                hereditary injtj.y per million persons-rems
                Prediction
                based on        Neoplasm       Hereditary
                                                   Organ
2 dpm/g
5 dpm/g
10 dpm/g
20c'pm/g
12.5
5
2.5
1.2
0.25
0.10
0.05
0.02
0.025
0.01
0.005
0.002
                                                  Lymph Node*
                                                  Bone
                                                  Liver
                                                  Kidney
                                                  Gonods
Plutonium 23v

  0.9
 43.7
  3.2
  1.3
  0.2
  0.05
                                                                                       data from:    Lung
A.Vm*.
Dog
Rot
 16-110
   70
60(700***)
Bone

2-17
 70  ,
 10
 20
                                                                                                                          50*
            > may be produced by cnn r-ar(!c'c
      cbout 4 pm in dlo.T.eier, end is equivalent
      to oboat 20 miliireiiiv.
                                                      Assumes thai particles arc rctoir.c.i
                                                      for o lo.'igoi t-cno'J of. time in t..o
                                                      (ong. {Adapted hum Hef. IS)
*    BE1R Report (olso 1-7 cases of liver cancer
     per.million per:on-rems)
**  50 ca;es ptr irillicn person-rems for
    immcdiatt?  fqnijly, SCO cq'
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                      Enclosure II

                  DEPARTMENT OF ENERGY
            COMMENTS ON DECONTAMINATION COSTS
        DISCUSSED IN THE EPA PROPOSED GUIDANCE ON
DOSE LIMITS FOR PERSONS EXPOSED TO TRANSURANIUM ELEMENTS
               IN THE GENERAL ENVIRONMENT

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                               CONTENTS
  I.   APPROACH
 II .   COSTS AND ECONOMIC  IMPACTS ......  ......... II-l
      GENERAL CONSIDERATIONS .......  .......... H_l
      COST ESTIMATION  FRAMEWORK  .....  .....  ....  .11-5
      COST DATA ....................... n_8
      COST ANALYSIS  ....  ................. H-15
      REFERENCES ....................... H-25
APPENDIX  A -  SITE DESCRIPTIONS . ...... , ....... A-l
APPENDIX  B -  SAMPLING ............. ....... B-l
APPENDIX  C  -  REFERENCE DECONTAMINATION PROCEDURES ...... C-l
APPENDIX  D  - UNIT COST DETERMINATIONS .........  .  .  . D-l
APPENDIX E - ECOLOGICAL IMPACTS ............  ... £-1

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                         ESTIMATE OF POTENTIAL COSTS
                    OF HYPOTHETICAL CONTAMINATING EVENTS
                                I.   APPROACH

     In processing, transporting, and using transuranic materials, stringent
measures are taken to prevent accidental releases of the materials to the.
environment.  Should accidents occur, similar rigorous attention would be
paid to minimizing risks and injuries to people and property in or concerned
with the affected geographic areas.  Nevertheless, it is reasonable to examine
the potential effects that application of the proposed Guidance might have
on the costs and on the economic and ecological impacts associated with decon-
tamination procedures.
     For purposes of conducting such an analysis, hypothetical accidental
releases of transuranic materials were assumed to have occurred at each of
three real, but not identified, sites in the United States.   (See Appendix A
for descriptions of these sites.)  The analysis was,based on  the alternative
assumptions that l-km2 and 10-km2 areas were found after the  hypothetical
contaminating events to require remedial treatment under the  proposed
Guidance.   Cost estimates included expenses expected  to be  incurred  in the
conduct of  an appropriate sampling program  (described in Appendix B).  The
sampling program would be needed to  define  these  areas, determine the types
of treatment required, and assess  the effectiveness of these  treatments  after
their  application.   Cost estimates were made  in  each  instance for application
of a variety of treatments that  would be acceptable under  the Guidance,
including:
   •   in-place  stabilization  by the application of a relatively impermeable
      cover  and by  limiting  area  access  and  use
   *   Dilution  by  plowing or  other  similar  techniques
   «   Disposal  by  removal of surface soils  and burial  either onsite  or in a
      designated waste storage repository.
                                      1-1

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 Application of these treatments was assumed to be accomplished through a
 series of steps appropriate to the conditions at the sites (see Appendix C).
      Costs for cleanup and for long-term stabilization and access-restriction
 alternatives were calculated by estimating unit costs for all  critical compo-
 nents (Appendix D), then applying these costs to the specific  circumstances
 at the respective sites.  Activities assumed, for purposes of  cost estimating,
 to be involved in the treatment of contaminated areas included initial sam-
 pling and monitoring to locate and assess the degree of contaminated  soils
 and materials; population evacuation,  maintenance,  and radiological monitor-
 ing; plowing or removal  of contaminated vegetation  and soils,  and  cleaning
 of structures; temporary storage of contaminated materials; packaging, trans-
 port,  and permanent disposal  of contaminated  materials;  post-cleanup  monitor-
 ing; and  restricted area maintenance.   In addition  to direct treatment costs,
 estimates of costs  from the interruption  of economic  activities were  also
 made.
     The  analysis of costs  and  economic  impacts  is  presented as the main body
 of  this t-eport because the estimates of these impacts appear to be the most
 significant  results  of  the  study.   All other material  that supports the
 analysis  of  cost and  economic impacts  follows  in Appendices A-D.  Also
 included  is  Appendix  E, which presents a  general description of probable
 ecological impacts.   Assumptions basic to the  study are presented in Table 1,
which appears  in the  Costs and  Economic Impacts Section.
                                     1-2

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         :.-.:..    -    n.  COSTS AND ECONOMIC  IMPACTS    ,

      This  section  presents an analysis of  possible costs attendant, to decon-
 tamination and related activities  that might be necessary following an
 accidental release of  transuranic  materials.                        :     .
      A number of factors would  affect these costs.  The equations  developed
 in this section  account for  the major factors, including the  size  of the
 area  affected, the length of time  that the area would  be affected, and the
 type  and level of  normal economic  activity in  the area.
                                                     .... '    . •••.;;•.
 GENERAL CONSIDERATIONS                                .                .
      The analysis  of costs presented here  is sensitive to a number of
 assumptions,  exclusions, and simplifications.  A list  of the  principal ones
 is provided  in Table 1 for convenient reference.  They are"developed more
 fully in the text  that follows.
      Decontamination of areas  impacted by  a  release of transuranic material
 might be accomplished  under  the Guidance in  several ways,  including site
 restriction, stabilization,  earth  removal, or  dilution through  plowing.
 Buildings and other structures  would  have  to be  handled  by  other techniques.
 The costs and effects  of  these  methods would differ for  any given situation.
 The decontamination of a  site might be  handled best by a  combination of
 techniques applied to  different portions of  the  total  area  to achieve  the
 desired result.   Since the number  of potential combinations for any site
 would be large,  however,  the analyses  reported here assumed use of only  one
 treatment at a time for all  relevant portions  of a  site.   The cost estimates
/derived from application  of the various  methods  on  each  site  were then
 compared to suggest treatment  cost ranges.
                                   II-l

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  TABLE 1.   Important Analytical  Assumptions,  Exclusions,  and Simplifications
  1
  2.
  3.
  4.
 5.


 6.
 7,


 8.
This study considers potential costs associated with hypothetical
accidental releases of transuranic materials.  It does not consider
any actual contaminated sites or releases associated with routine
facility operations.

The study does not consider effects associated,with the events occurring
during and immediately after the accidents; it deals only with the effects
of treating the contaminated areas resulting from the accidents.  Treat-
ment is taken to include, however, both initial sampling and any necessary
evacuation of people from affected areas.

The site descriptions were based upon real, uncontaminated areas;
therefore, real land use, economic, and ecological data were used in
the analyses.

Cleanup cost estimates were based upon the assumption that adequate dose
rate reductions would be achieved on the first application of the
selected treatment to each contaminated area.  Not included are the
costs that would be incurred if the treatment had to be repeated to
reduce contamination to acceptable levels.

Costs for packaging, transporting, and disposing of contaminated earth
removed from an area were based upon removal of soil to a depth of 5 cm.

Estimates derived in this study represent total costs for dealing with
the accidental releases in compliance with the Guidance, rather than
marginal costs representing the differences between working with and
without the Guidance.  The total-cost approach is consistent with the
approach taken by EPA in the estimates provided in the Guidance.

The estimates were calculated from unit costs for materials, equipment,
and labor, based upon national averages.

The costs of having crews and equipment idle while awaiting post cleanup
sampling results were not included in the estimates.
 9.  Costs for shipment of decontamination equipment or crews to affected
     areas were not included in the estimates.

10.  The population located within areas designated for treatment was assumed
     evacuated as a part .of the treatment process.  It was assumed that the
     average evacuation period would be 30 days.

11.  No cost estimates were included to cover expenses associated with environ-
     mental impact analyses, environmental impact statements, or potential
     litigation arising from possible contaminating events and subsequent
     cleanup activities.
                                    II-2

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                             TABLE 1. (contd)
12.  Psychological trauma and othfr nonquantTflable effects of treatment
     measures for qontaminated areas were notassessed.

13.  Health effects from radiological exposures or other hazards associated
     with treatment of contaminated areas were not estimated.
                                  II-3

-------
      The Guidance specifies that remedial  treatment of contaminated areas     *
 would be necessary wherever the dose rate  to individuals residing in the      •
 affected areas would exceed 1  mrad/yr to the pulmonary Tung or 3 mrad/yr      '<
 to the bone.   The Guidance also indicates  that areas in which the transuranic
                                                             2
 contamination in the top cm of soil  did not exceed 0.2 wci/m  could be
 considered safe without remedial  treatment.  For purposes of the illustrative  !
 analyses conducted in this study, it was assumed that an appropriate'
 sampling program (for which costs were included) had led to the delineation
 of areas requiring remedial  treatment, based upon these criteria.   Costs    K
 and ecological  effects estimated  for each  of the three reference sites
 considered were based on the alternative assumptions that the sizes of
                                        22
 the areas requiring treatment  were 1  km or 10 km .
      The costs  of remedial  treatment of contaminated sites would be
 dependent upon  factors heavily influenced  by either area size or the time
^required to effect the treatment.   The main cost elements that would be
 more affected by time than by  area are the possible costs of evacuation
 and production  loss.   While  initial  evacuation costs may be thought of as
 an independent  factor,  the costs  to  the population during decontamination
 would be directly dependent  on the length  of time involved.   The monetary
 loss experienced by nonagricultural  workers,  for instance,  would depend
 largely  on the  amount of time  these  workers were prevented  from working.
 Agricultural  production losses would  depend on the time required to bring
 land back into  production at a level  equal  to that prior to  contamination.
 These losses  were estimated  here  on  the basis of average production levels
 and  product values.   The actual losses from a. real  accident  would  vary
 greatly  from  site to  site and  from one commercial .activity  to another  within
 sites.
      The  cost calculations presented  here  were formulated on  the basis of
 estimated  average costs  for  wages, materials,  equipment,  evacuation  expenses,
                                2
 etc.,  required  to treat each km  of affected  land  of a  given  type or use.
While  one might  prefer  for the sake of greater accuracy  to apply scale economy
 and  marginal  cost principles,  their use would  necessitate firm assumptions on
 cleanup timing  and  on equipment and Tabor  availability  in the affected area at
                                   II-4

-------
Ithe specific time they were needed.  Unless consistent for ,all cases
Istudiedvjthese assumptions would detract from the usefulness of the analyses
pf various cases fprr comparative 'purposes,  ft 'is not expected that the error:
Jin cost estimates resulting from the,exclusion of scale economy and marginal
cost principles was unacceptably .large, given the purposes of the .analysis  .
'and other necessary assumptions, exclusions, and simplifications that affected
the results.
COST ESTIMATION FRAMEWORK                                 .
     Once areas and contamination levels in a situation have been identified
and treatment techniques chosen, the total costs of decontamination of an
area may be estimated by the cost equation:
TC,
/Tr.-1-alv  :
(Sst)  •
      '
ET
                   KP
n=l
               M
                                      KP
                                n=l
S
             / Population   \
             ( Hon1tpr1ng.& •).
             \Decontam1 nation/  v " iamp ' ' ng '
                                                                    111    ,
                                            DKe
           + (Decpntamination)  +   (Temporary Burial)
                                             + (Final, Buria.l)
                 >Sl
                        -r.
               /Rural Land \
               \Reclamation/
                    /Urban Land \
                    IReclamation/
                                                         +   X,    I   .K 1
                                                                 r=l
                                                           /AgriculturalX
                                                         + (  Production  )
                                                        .   \    Loss     /
           +     (Manufacturing b Other Production Loss)
                                   II-5

-------
where:
          TC, = Total cost of decontamination-related activities and
                compensation
            E 3 Evacuation cost per capita per day
            M - Cost per capita for population monitoring and decontamination
            S = Cost of preliminary site survey and sampling
                                 2
            P s Population per km
            Q = Cost of surveillance
            T = Estimated time to complete decontamination
                               2
            K = Land area in km

            n = Number of land areas to which a unique set of decontamination
                procedures is applied
            r = Rural
            u * Urban
           K  = Area in km  where earth removal is used
            e
                               O            '                     ,
            A = The cost per km  of each unique set of decontamination
                procedures (labor, machinery and supplies)
                                             2
            L s Land reclamation costs per km
                                                  2
            D = Temporary burial site costs per km  (stabilization  plus
                monitoring costs)
                                             2
            F = Cost of final disposal per km
X,, X2 and Xj = Production losses (agricultural, manufacturing and  other
    t            in that order).                ,
     In cases where the total decontamination costs were found to exceed
the estimated value of the area, stabilization of the contaminant and
restriction of the site might be desirable.  If so, the following cost
equation would be appropriate to estimate total cost:
                                   II-6

-------
      TC,
                 ET
MKtP
:      Trt.al                   /  Population   V
I...     I0"'  = (Evacuation) +(  Monitoring &   )  >
;      LOSu
                                                            \
                                                            r (Surveillance)
                                                            /
                   RKtP
                                     (Z + Y..+ V)K.
                                 \ Surveillance /
where:
     TC2 = Total cost of site-restriction-related activities and compensation
       E = Cost of evacuation per capita
       M = Cost of population monitoring and decontamination per capita
       S = Cost of preliminary site survey and sampling
       Q = Cost of surveillance
                                            2
      Kt = Total area to be restricted in km
       T = Time until decision is made to relocate the population
                            2                . .     .-..•.            ••.-.•
       P = Population per km                                	';;,.,.
       R = Per capita relocation costs including compensation for produc-
           tion losses
                                                            2      ' '  ''' ''
       Z = Condemnation value of site and buffer zone per km
       Y = Cost of site stabilization per km
                               2
       V = Present value per km  of site surveillance.
Where a situation dictated restriction of part of the area and decontami-
nation of the remainder, the two cost equations could be applied to the appro-
priate portions of the total area and summed to estimate total cost.
                                    11-7

-------
COST DATA
                                     $561,500/knT
                                               ,2
      Using the treatment measures assumed to be applied to the sites of
 hypothetical  transuranic contamination, point estimates were found for'the
 costs incurred from the time of the accident until  the land was restored
 to its original  use and disposal  of the transuranic wastes was complete.
 The unit costs (including overhead) given in Table  2 were used to compute
 the site cost estimates.  A discussion of the procedures used to determine
 these unit costs is presented in Appendix D.
     In order to find the cost of the set of procedures called for in the
decontamination of a given land type, the land area  in one use (Kn), shown
in Table 3, was multiplied by the sum of appropriate procedure unit costs (A(
from Table 2.   Examples of the estimated costs of decontamination procedures
(in 1977 dollars for earth removal, not including reclamation) for various
land types are as follows:
                    Forests
                    Cornfields
                    Plowed Farmland
                    Pasture
                    Residential Area
                    Industrial Area   $897,000/kmt
To derive the cost of decontaminating commercial and residential areas,
some assumptions on the composition of these areas were made, as presented
in Table 4.  The production-loss and real estate values used are given there
also.  While production losses and real estate values for agriculture would
depend on the land area affected by the contamination, commercial production
losses and commercial real estate values would depend both on the population
employed and on. capital investment.  Since capital investment data are not
readily available, however, the cost estimates here were computed on a per
capita basis.
     From the unit costs and assumptions regarding land use, costs were
estimated for all aspects of decontaminating and managing each s1te»  These
are given in Tables 5 through 7, using earth removal on the contaminated soil
areas.  The total cost for each site is rounded to the nearest $100,000.
                                     $423,000/km^
                                     $403,000/kmJ
                                     $403,000/km*
                                     $611,000/km2
                                  11-8

-------
      TABLE  2.  .Unit Costs for Area Decontamination  and  Management
 Two Weeks of Water, Fixation            ,
 Long-Acting Stabilizer
 Corn Removal
 Other Crop Removal
 Earth Removal (Grader)
 Earth Removal (Front-End Loader)
 Earth Removal (Manual Labor)
 Field Sod Removal
 Lawn Sod Removal            '
 Vacuumized Sweeper
 Fire Hosing
 Homes
 Population Monitoring & Decontamination
 Evacuation, Including Room, Board,
   Transportation and Personnel(2, p. 12-3)
 Lawn Resodding
 Topsoil Replacement
' Erosion Control
 Fertilizer + Seed (Materials Only)
 Temporary Storage Sites (Except Land Cost)
 Plowing
   25 cm
   1 m, Tilled Land
„ ,1 m. Pasture, Including
     Reseedingd, p. 12-11)
 Surveillance (Based on Perimeter Length)
 Commercial Areas
 Disposal (1000 Miles of Transportation,..., ,
   2-in. Soil Removal, Federal Disposal Site)
 Biobarrier (Labor and Materials)
 Fence (Based on Perimeter Length)
 Present Value of Future,.Surveillance
      44,500/km
      62,500/km2
      12,000/km2
       2,500/km2
     137,odo/km2
     250,000/km2
     430,500/km2
     137,boo/km2
     17T-,000/km2
      24,000/km2
      3d,0.00/km2 -
        200/home,
      300/person
15.00/person/day;
     945,,000/km2;
   1 J83,500/km2
     154,500/km2
      48,506/km2
       2iOOO/km2
     ..  2,OOQ/km'
     JZl.OOO/km2
        3,500/km
     543,500/km2
  10,752,
  ,:-   :.35-,0007km
   .;,   .100,000/km,
 Cost Plus Burden
  $   73,500/km2
     103,500/km2
     , 20,000/km2
       4,000/km2
     226,0007km2
   '' 412,500/km2
     710,500/km2
     226,000/km2
     282,0007km2
      40,0007km2 --
       50,000/km2
        350/home
   1,275,500/km"
   ^s597,500/km^
     208,500/kmJ
      65,000/km2
       3,5007km2
       3,500/knT
      34,5,00/,km2

   -  T50,060/km2
  ;     ,6,000/kni
:  .   897iQOO/km2

 119,200,0007km2
  17,742,0007km2
  -,    •.47,000/km
 NOTE:  Burdened costs include overhead (25%), loss of efficiency due to protettive
        clothing (30%), workmen's compensation and social security (10%), except for
        land reclamation costs which do not require?protective clothing and ioclude
        only overhead and social security.  All unit costs are rounded to     ^
 •.-•-'•    nearest $500.   ;  .    •/-;'-  •-.,•-';••-• .;•••;'.•&:.-•**•;;•-•-•-  •••^-••.-.?-.-•:; ....'^ r^-.
                                      ri-9

-------
TABLE 3.  Land-Type Breakdown by  Site  for  1.0-km2  and  10.0-km2  Areas3
    Reference Site One
    Corn Fields
    Plowed Farmland
    Hay and Soybeans
    Pasture Land
    Residential Area
    Wood!ots
    Industrial Areas
    Population
    Perimeter
    Reference Site Two
    Forest
    Shoreline
    Residential Area
    Population
    Perimeter
    Reference Site Three
    Pasture Land
    Field Crops
    Orchards
    Ditches
    Residential Area
    Population
    Perimeter
   1.0 km'
  10.0 km'
   0.37 fair
   0.25
   '0.13
   0.11
   5 Homes
   0.09
   0.05
 15 Persons
   2.5 km

   0.21 km2
   0.22
   0.57
2269 Persons
   2.5 km

   0.58 km2
   0.31
   0.07
   0.03
   0.01
 39 Persons
   2.5 km
   3.70 km-
   2.50
   1.30
   0.60
   1.40
   0.30
   0.20
5475 Persons
   15.1 km

   3.96 km2
   3.96
   2.08
8202 Persons
  15.1  km

   5.80 km2
   3.17
   0.70
   0.30
   0.03
120 Persons
  ]5.1  km
a)since these sites are real,  the mix of land  types and the land uses
  varies with area size; therefore,  the  composition of the 10.0-km2
  area at each site is not necessarily proportional to the composition
  of the 1.0-km2 area.                            '
                                11-10

-------
                    TABLE  4.  Assumed Values  for Derivation
                             of  Decontamination Costs
 Average  annual  value of  production of agricultural land per km  = $24.000.
 This  figure was computed from the value of cash receipts plus home consumption
 for U.S.  farmland given  in the 1976 U.S. Agricultural Statistics^) and adjusted
 to 1977  dollars.A2-yr loss of production is assumed for earth removal and
 plowing  to 3  ft.

 Median value  of a single-family dwelling— $40,000.  This figure was taken from
 a 1976 study  by the MIT-Harvard Joint Center for Urban Studies and adjusted to
 1977  dollars.

 Value of commercial land and structures = $5,000 per capita.  This figure was
 computed  from a National  Bureau of Economic Research publication'*) and adjusted
 to 1977  dollars.

 Average  value of agricultural land and buildings per km  - $148,000.  This figure
 was taken from  the 1974  Census of Agriculture^) and adjusted to 1977 dollars.

 Manufacturing production loss = $250.value added per capita per month.  From the
 City  and  County Data Book of 1972,t6/ adjusted to 1977 dollars.

 Other production loss =  $300 per capita per month.  This figure was taken from
 the-1970  Census of Population^7) information on earned incomes, adjusted to 1977
 dollars.

 Decontamination procedure period = 1 year.

 Evacuation period = 30 days.

 Composition of  residential areas:  (taken from WASH-HOOT1' p> 12~12')---

      57% lawn and fields     20% pavement     23% home and roofs

 Composition of Commercial areas;  (taken from WASH-1400 r1'  p* 12~5V

      50% building            50% pavement

 Relocation costs per capita = $3,500.   This cost was  taken from WASH-1400,
 (Ref. 1, p. 12-5) adjusted to 1977 dollars.

 Final disposal costs are computed on the basis of figures  given in BNWL-2210.,^8^
 Tri-State Motor Transit Company,(9)  and GESMdO°).  The transportation
 distance is assumed to be 1000 miles (1609 km) for all  sites.
                 2
 Residences per km  = 1235 and persons  per residence = 3.2.   These  figures,
 assumed for the site of each accident  scenario, correspond to  the  medium-
density residential  pattern described  in WASH-1400.(Up.  12-4)
                                    u-ir

-------
         TABLE  5.  Reference Site One:   Decontamination Costs
for Earth Removal TO
and 10.0 km2

Cost Element Description
n
ET £ ICP Evacuation
n=l n
M S K P Population Monitoring
n=l n and Decontamination
S Survey and Samples
Q Surveillance1
n
£ K Ah Decontamination:
n=l n n Corn Fields
Plowed Farmland
Hay and Soybeans
Pasture
Woodlots
Residential Areas
Industrial Areas
DK Temporary Storage
e
FK Permanent Disposal
Z K L Land Reclamation
u
Z K L Lawn Resodding
r Production Losses:
v r v T flnririilt.iiral
\r Areas or i .u K

Costs (
1.0 km^
$ 6,800
4,500
161,500
15,000

156,500
100,800
52,900
44,300
50,500
1 ,800
44,900
3,300
113,240,000
1,616,500
—i—
45,600


$ 1977) .
10.0 km^
$ 2,463,800
1,642,500
1,069,200
90,600

1,565,100
1,007,500
529,100
241 ,800
168,500
855,400
269,100
32,200
1,096,640,000
16,039,900
1,020,400
403,200
X3  E
 3 n=l

    TC
Manufacturing


Other


Total Cost
      3,800         1,368,800



      4,500         1,642,500


115,600,000     1,127,000,000
 NOTE:  Total cost is rounded to the nearest $100,000.
                                  11-12

-------
     TABLE  6.   Reference Site Two:   Decontamination Costs for Earth
               Removal  for Areas  of 1.0 km2 and 1.0 km2
Cost Element
     n
     S.

     Q
    DK
                       Description
 ET  X   K_P    Evacuation
    n=1  >

     n
  M , X   K P    Population Monitoring
    n=l         and Decontamination
         KULU
          u u
n
x
    TC
           Survey and Samples

           Surveillance


           Decontamination:

             Forest
             Shoreline
             Residential Area

           Temporary Storage

           Permanent Disposal


           Land Reclamation



           Lawn Resodding

           Production Losses:
         KnPT   Other
           Total Cost
                                                  Costs  ($ 1977
                                        1.0
                                               680,700
                                              395,800

                                               15,000
                                              117,900
                                              135,800
                                              348,300

                                                2,600

                                           89,400,000


                                               43,800



                                              414,400
                                              680,700
                                           93,300,000
 977)
 ToTtT
                                           $ 1,021,100    $    3,690,900
                                                         2,460,600
    1,361,300

       90,600
    2,223,500
    2,444,800
    1,270,900

       31,900

1,084,720,000


      825,700



    1,512,200
    2,460,600


1,103,100',000
NOTE:  Total cost is rounded to the nearest $100,000.
                                 11-13.

-------
  TABLE 7.  Reference Site Three:  Decontamination Costs for Earth
Removal for Areas of 1.0 km^ and lO.u war-
Costs ($ 1977)
tost
ET
N













Xl
x3

Element
n
2t/ n
^__ r
n
n'l K"P
S
Q
n
* KnAn
1 ii ii


DKe
FKQ
e
j, VT
u
Jl. ^

r
Si/ ^p
**w* 1
n
Z K PT
nsl
TC
Description
Evacuation
Population Monitoring
and Decontamination
Survey and Samples
Surveillance

Decontamination:
Pasture Land
Field Crops
Orchards
Ditches
Residential Area
Temporary Storage
Permanent Disposal

Land Reclamation
Lawn Resodding
Production Losses:
Agricultural
Other
Total Cost
1.0 kn£
$ 17,600
11,700
164,100
15,000


233,700
126,200
41,300
17,700
6,100
3,500
118,723,200

1,771,500
7,700

47,500
11,700
121,200,000
10.0 km^
$ 54,000
36,000
517,700
90,600


2,337,400
1,290,300
413,000
177,000
18,300
34,900
1,189,616,000

17,841,000
25,500

478,600
36,000
1,213,000,000
NOTE:  Total cost is rounded to the nearest $100,000.
                                 11-14

-------
 Table. 8 presents the estimated costs  if plowing were used on open areas of
 reference sites 1 and 3.  Plowing was  not  considered feasible on the other
 site since the land areas there w«§re*largely residential, forest, and
 shoreline.

      Cost estimates for  site restriction  for the three accident sites are
 given in Table 9.  The costs of  site  restriction were based on the
 assumption that the land would be condemned, with the least contaminated
                   -----                                                * •
 half decontaminated and then planted with vegetation.  The wastes would be
 spread on the more highly contaminated half, which would then be covered with
             (2\
 a biobarrierv ; of rock, earth, and vegetation.  Fencing would be erected
 and a surveillance system established.  This stabilization of the contaminant
 would be used until the technology of transuranic recovery or disposal, or
 the demand for land, changed to make decontamination of the site both
 technologically and economically feasible.

 COST ANALYSIS

     In developing the cost estimates for the study, it was assumed that
following an accident, the transuranic contamination would lie on the land
surface and be almost totally removed by a single application of the decontam-
ination technique appropriate to that surface area.   On open areas, earth re-
moval , plowing, and site restriction were considered mutually exclusive alter-
natives.   As a result, a  cost  gradient related to contamination level  is not
apparent in these cost estimates.   The cost estimates prepared for WASH-1400^
do show a cost gradient, but that report deals with  radionuclides in different
forms and with different characteristics from those  of the transuranics con-
sidered in the present study.

      A comparison of the pertinent costs of  decontaminating and  reclaiming
 a  square  kilometer  of cropland  by dilution (plowing) or removal  of the
 contaminant,is shown  in Table  10.   This comparison  indicates  that, where
 the  contamination level  and  land  characteristics permitted substitution of
 plowing for  earth removal, plowing  would result in a substantially lower
 cost.  None  of the  population-related  costs  likely to be  incurred  are
 included  in  this example.
                                   11-15

-------
             TABLE 8.  Comparative  Decontamination  Costs ($  1977)  for
             	   Areas  Where  Plowing  is a  Feasible Alternative
                                                                                     25-cm Depth
Cost Eleiw
Reference
n
£ K A
n«l
DKC
r
u
>nt Description
Site One
Corn Fields
Plowed Farmland
Hay and Soybeans
Pasture
Woodlots )
Residential Areas > Earth
Industrial Areas J Removal
Temporary Storage
Land Reclamation
I awn Rpsoddino
1.0 km*

$ 87,700
81 ,800
28,000
36,000
50,500
1,800
44,900
300
1,627,900

r 10.0 km*

$ 856,600
817,500
280,200
196,200
168,500
855,400
269,100
3.900
15,217,700
1,020,400
1.0 km*

$ 74.200
45.100
24.000
19.900
50.500
1.800
44.900
300
205,200
..
10.0 taf

$ 741 .900
451 .300
239.900
108.300
168.500
855,400
269.100
3.900
1.790.400
1.020.400
X. : K T Agricultural Production Loss
FK '*
e
TC
Reference
Jl KA
DKe
1 KrLr
Final Disposal

Total- Decontamination-Related Cost
Site Three
Pasture Land
Field Crops
Orchards
Ditches
Residential Areas
Temporary Storage
Land Reclamation

\ Earth
) Removal


45,600
10,728,000
12,700,000

189,700
66,800
41 ,300
17,700
6,100
500
1,854,000
403, 2UU
131,120,000
151,200,000

1,896,600
683,100
413,000
177,000
118,300
3,600
18,675,600
•
10,728,000
11,200,000

104,700
: 57.200
41.300
17,700
6,100
500
354,200
cui ,ouu
131,120.000
137,000.000

' 1,046,900
584.900
413,000
177,000
118.300
3,600
3,557,000
    'u u
TC
Lawn  Resodding                            7,700          25,500

Agricultural Production Loss               47,500         478,600
Final Disposal                        18,714,400     121,584,000
Total Decontamination-Related  Cost      20,900,000     144,100,000
    7,700

    23.800
18.714,400
19,300.000
    25,500

   232.800
121,584,000
127.700.000
NOTE:  Total cost is rounded to the nearest $100,000.  Population-related costs are not Included  since they do
      not depend on the decontamination  method chosen.
                                               XI-16

-------
;n,i,j     (
                                          TABLE 9.  Site Restriction Costs ($1977) for  Reference
Site Areas of 1.0 km* and 10.0 km*
Cost
Element
ETKtP
MKtP
S
Q
RKtP
ZKt



YKt
VKt
TC
Description
Evacuation
Population Monitoring
and Decontamination
Survey and Samples
Surveillance
Population Relocation
Real Estate Value:
Agricultural
Residential
Commercial
Stabilization and
Restriction
Present Value , «
of Surveillance13'
Total Cost
Reference
.0 km2
$ 6,800
4,500
161,500
t; 15,000
52,500

140,600
200,000
75,000
94,298,000
. 250,000
95,200,000
Site One
10.0 km2
$ 2,463,800
1,642,500
1 ,069,200
:>. 90,600
19, 162', 500 ;

1,243,200
69,160,000
27,375,000
938,731,000
1,510,000
1,062,400,000
Reference
1.0 km*
$ 1,021,100
680,700
395,800
15,000,,
7,94f,50qj!

63,600
28,158,000
—
95,015,000
250,000
133,500,000
Site Two
10.0 km*
$ 3,690,000
2,460,600
1,361,300
90,600
" 28 * 7Q7i*QQO ''"

1,172,200
102,752,000
_.
938,908,000
1,510,000
1,080,700,000
Reference
1.0 km* .
$ 17,600
11,700
164,100
-"• -.; 15*000
•';.. 136-|500
vmzixm^.aK,.-' ,:
146,500
494,000

94,191,000
250,000
95,400,000
Site Three
10.0 km?
$ 54,000
36,000
517,700
90,600
420,000

1,475,600
1,482,000

937,082,000
1,510,000
942,700,000
                (a) 100-year period.
                NOTE:  Total cost  is rounded  to the nearest $100,000.

-------
      TABLE 10.  Cost Comparison for Removal and Dilution Techniques
                 for Transuranic Contamination of 1 km^ of Cropland
                 ($ 1977)
                             Earth Removal
                          Plowing
           Activity
      Soil Stabilization
      Decontamination
      Temporary Storage
      Final Disposal
      Reclamation
      Production Loss
        Total
. (Grader)
$ 177,000
226,000
3,500
(a)
119,200,000^ '
1,806,000
48,000
1-m Depth
$ 177,000
34,500
—

---
1,871,000
48,000
25-cm Depth
$177,000
3,500
. —

~— »
208,500
24,000
$121,460,500V ;  $2,130,500     $413,000
         If ultimate disposal  of  the  contaminated were  in a commercial
         repository instead of a  Federal  repository,  the estimated cost
         for that factor would be $14,700,000, and the total  cost for
         the soil removal  treatment as defined in this table would be
         $16,960,500.(8,9)

     In agricultural and nonurban areas  in general,  the cost  of final
disposal of the earth removed accounted  for approximately  98% of the total
estimated cost per km2, shown in Table 10.  In residential areas final
disposal accounted for 92% of the total  estimated cost.  If commercial  instead
of Federal repositories were used,'these numbers would.be  85% and 50%,
 respectively.  The effect of  final disposal cost on  total costs  indicates
 that examination of alternative  means of dose reduction (e.g., dilution and/
 or site restriction) would be warranted  in a  real accident.   If  the commercial
 repositories are assumed, then population evacuation and monitoring costs
 and production losses become  the largest items  for  the residential  and
 commercial areas.
      Cost comparisons of alternative means of complying with the Guidance
 for contaminated areas are given in  Table 11  for the 1  km2 areas and Table 12
 for the 10 km2 areas.  Although comparative costs are  presented  for plowing,
 site restriction, and earth removal, it does  not necessarily follow that
                                    11-18

-------
TABLE  11.  Cost  Summary  for Reference Sites 1.0 km2 In Area
,„„,,.- iv^;, -^i Fflpth --' -
Cost Categories *^Removal
-Reference Site One-
Evacuation and Monitoring
Samples and Surveillance
Decontamination
Temporary and Final Disposal
Land Reclamation
Production Losses
Real Estate Purchase
Population Relocation
Site Stabilization
Total
-Reference Site Two-
Evacuation and Monitoring
Samples and Surveillance
Decontamination
Temporary and Final Disposal
Land Reclamation ,
Production Losses
Real Estate Purchase
Population Relocation
Site Stabilization
Total
-Reference Site Three-
Evacuation and Monitoring
Samples and Surveillance
Decontamination
Temporary and Final Disposal
Land .Reclamation
Production Losses .
Real Estate Purchase
Population Relocation
Site Stabilization
Total

$ 11,300
176,500
451,700
113,243,300
1,616,500
53,900
—
MM-
— — ""
115,600,000

$ 1,701,800
410,800
602,000
89,402,600
.458,200
680,700
MM
MM
M.
93,300,000

$ 29,300
179,100
425,000
118,726,700
1,779,200
59,200
— « ,.
MM
M«
121,200,000
Plowing,
1 m(a7

$ 11,300
176,500
328,700
10,728,300
1,627,900
,53.900
MM
M^
' " MM
12,900,000

$
__
,
-_
__
__
-"."
^^ t
^M
—

$ 29,300
179,100
321 ,600
18,714,900
1,861,700
59,200
^ ^
—
..
21,200,000'j
Plowing.
25 cmU)

11,300
176,500
260,400
10,728,300
205,200
31,100
^•m


11,400,000

$
MM
-' " - - MM
MM
_„
• V



...

$ 29,300
179,100
227,000
18,714,900
361,900
35,500



19,500,000
(a) Earth removal is assumed to be used in areas not suited to plowing
(b) Site restriction costs are based on construction of a biobarrier
(c) Site restriction surveillance is for a 100-yr period.
NOT? * Trtf*a 1 f*f\c+ T ff M«wiM.«4«k«4 4. A £.!._ 	 _L rf>* MA f*A
                                                                 Site  ,M
                                                            Restriction^
                                                                  11,300
                                                                 415,600
                                                                  52,500
                                                              94,298,000
                                                              95,200,000

                                                            $   1,701,800
                                                                 660,800^
                                                             28,221,600
                                                              7,941,500
                                                             95,015,000
                                                            133,500,000

                                                            5     29,300
                                                                640,500
                                                                136*500
                                                             94,191,000
                                                             95,400,000
                           11-19

-------
                                                                         2
           TABLE 12.   Cost Summary for  Reference  Sites 10.0 km  in  Area

Cost Categories
-Reference Site One-
Evacuation and Monitoring
Samples and Surveillance
Decontamination
Temporary and Final Disposal
Land Reclamation
Production Losses
Real Estate Purchase
Population Relocation
Site Stabilization
Total
-Reference Site Two-
Evacuation and Monitoring
Samples and Surveillance
Decontamination
Temporary and Final Disposal
Land Reclamation
Production Losses
Real Estate Purchase
Population Relocation
Site Stabilization
Total
Earth
Removal

$ 4,106,300
1,159,800
4,636,500
1,096,672,200
17,060,300
3,414,500
—
«
—
1,127,000,000

$ 6,151,500
1 ,451 ,900
5,939,200
1,084,751,900
2,337,900
2,460,600
—
~
—
1,103,100,000
Plowing,
1 m(a)

$ 4,106,300
1,159,800
3,443,500
131,123,900
16,238,100
3,414,500
.
—
—
159,500,000

$ --
—
'
~

—
—
' —
.
—
Plowing.
25 cm(a'

$ 4,106,300
1,159,800
2,834,400
131,123,900
2,810,800
3,212,900
—
«
~
145,200,000

$ • , ~ ' '
—
—
'
— >
' . —
—
—
— .
.
Site ,.)
• i n I
Restrict! on l '

$ 4,106,300
( f* \
2,669,800^'
--
—
•

97,778,200
19,162,500
'938,731,000
,1,062,400,000-

$.. ,6,151,500
2,961,900^
-—
-- •,
— -

103,924,200
28,707,000
938,908,000
1,080,700,000
-Reference Site Three-
Evacuation and Monitoring
Samples and Surveillance
Decontamination
Temporary and Final  Disposal
Land Reclamation
Production Losses
Real Estate Purchase
Population Relocation
Site Stabilization
  Total



1





1


4
,,189
17




,213
90
608
,236
,650
,866
514
-
_
v
,000
,000
,300
,000
,900
,500
,600
-
_
_
,000
$

3
121
18




144
90,
608,
,288,
,587,
,701,
514,
-
—
—
,800,
000
300
000
600
100
600



000
s

2
121
3




128
90
608
,340
,587
,582
268
,
-
-
,500
,000
,300
,100
,600
,500
,800
-
-
-
,000
$ 90
2,118
"
-
-
-
2,957
420
937,082
942,700
,000

--
-
-
-
,600
,000
,000"
,000
    Earth removal  is  assumed to be used in areas not suited  to plowing.
    Site restriction  costs are based on construction of a  biobarrier.
 v.  Site restriction  surveillance is for a 100-yr period.
NOTE:  Total cost is  rounded to the nearest $100,000.
                                             11-20

-------
the least-cost method would be selected for application in a real situation.
Responsible officials would make their choice after considering not only cost
but also such factors as health risks, economic disruption, and ecological
                                 ••>*_>.•      >-..""!*£.-!•:-?'_•'" ••*:•&'
impacts.  For instance, plowing would be less costly than earth removal, but
equipment for 1-m plowing would probably not be readily available, and where
clay or loose rock underlay the topsoil, land reclamation problems caused
by plowing might be very costly.  Plowing to a depth of 25 cm would be the
least costly technique for use on open areas, but it might be less effective
1n reducing dose rates than would earth  removal or 1-m plowing.
     Site restriction without removal of the contamination., would only buy
time, shifting much of the cost into the future.  As.estimated in this report,
the costs of site restriction techniques->-excluding costs for population
evacuation, monitoring, and relocation; site purchase (necessary to eliminate
the economic burden on owners of affected land); and fencing—would range
                      2                 2
from about $415,000/km  to $9,000,0007km .  The low estimate would.be for
Initial sampling and surveillance, use ofI a short-term stabilizer, and,
revegetation.  This treatment would be comparable to the minimum treatment
estimate of $500/acre {$123,5007km ) noted in the Guidance.  The higher
estimate would be for use of a biobarrier.
                                                                    o
     Table 13 presents a comparison of estimated cumulative costs/km  for
all sites and treatments discussed in this report.  Differences in the costs
                              2          2
per unit area between the 1 km  and 10 km  areas are largely accounted for by
population evacuation and monitoring factors.  In real  instances, one would
expect greater differences due to scale economy effects.  As noted earlier,
the use of unit costs in this analysis precluded the demonstration of such
effects.
     Table 14 shows a comparison of unit costs developed in the DOE analysis
and those estimated by EPA.  The comparisons shown in the table are somewhat
contrived since the definitions of the items and the assumptions used by EPA
and DOE are, in many cases, quite different.  (See Table 1  and Appendices
B, C, and D for details of many of the DOE definitions  and  assumptions^)
                                   11-21

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                            TABLE 13.  Comparison of Estimated Cumulative Costs per
                                       Unit Area for'All Sites and Treatments
                Area
        1.0  km':
          Reference  Site One
          Reference Site  Two
          Reference Site Three
Treatment

    ER
    SR
    DP
    SP
    ER
    SR
    ER
    SR
    DP
    SP
                                          (a).
   Total  Cost
($ Million 1977)

     115.6
      95.2
      12.9
      11.4
      93.3
     133.5
     121
      95
      21
,2
,4
,2
               Cost/km
           ($ Hill ion 1977)
                115.6
                 95.2
                 12.9
                 11.4
                 93.
                133.
                                                       19.5
121.2
 95.4
 21.2
 19.5
    Cost/acre
($ Thousand 1977)

        468
        385
         52
         46
        378
        540
        490
        386
         86
         79
ro
        10.0 knT:
          Reference Site One
          Reference Site Two
          Reference Site Three
     ER
     SR
     DP
     SP

     ER
     SR

     ER
     SR
     DP
     SP
    1127=0
                                                      1062.
                                                       159,
                                                       145,
    1103.1
    1080.7
    1213.0
      942.7
      144.8
      128.5
                 112.7
                 106.2
                  16.0
                  14.5
                 110.3
                 108.1
                 121.
                  94,
                  14,
                                                                            12.9
                       456
                       430
                        65
                        59
                       446
                       437
                       491
                       382
                        59
                        52
        (a)ER = Earth removal to depth of 5 cm; DP = Deep (1-m) plowing; SP = Shallow (25-cm)  plowing;
           SR = Site restriction, including construction of a biobarrier.

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                       TABLE  14.    Comparison of  DOE and EPA  Unit  Costs  for  Area  Decontamination  and  Management
 I
ro
CO
th\
t Plus Burden10'
73,500/km2
103.500/km2
20.000/km2
4.000/kiu2
226,000/km2
412,500/km2
710.500/km2
226.000/kin2
282,000/km2
40,000/km2
. 50,000/kra2

Low Cost
$ 49,400/km2
128,400/km2



37.000/km2

8,600/km2




High Cost
$ 296,000/km2
163,00b/km2



405,100/km2

185,200/km2



Assumed
Unit Cost
$ 172.900/km2
148,200/kin2



148,200/km2

123,500/km2



350/home

...
1.275.500/km2
l,597,SOO/ki»2

208.500/km2

65,000/kra2
•t
3,500/knf
3.500/kn2
ISOioOO/kn2
6,000/kn

897.000/kn2
119.200,000/kn2
17.742.COO/ki82
47.000/kn



101,300/km2
352.000/km2

137.000/km2

54.300/km2

4.900/km2
••"$:*•' A
7,400/knf
.
30.000/yr


123,500.000/kn2

600/k«


9 '-
469,300/taT
774,300/km2

209.900/km2

175.400/km2

16.100/kin2
163,000/km2
57.000/yr


185.250.000/km2

3.400/ta


y
259,400/km
563,200/km2

, 179.100/km2

88.900/lp2

11.100/fai2
49,400/{m2
No estimate;


164,255.000/kn2

2.300/kn

IOO.OOO/kJc)
tPA uetlnuidns
and Assumptions
Short-term stabilization.
Long-term stabilization.
Ho estimate.
No estimate.

Scraping into mounds.


No estimate.
No estimate.
No estimate.
No estimate.
Ho estimate.
No estimate.
Seeding, not sod. .
Probably assumes open areas.
Assumes soil nucded on 95Z
of area.
Long-term stabilizer plus
mulch. ;,
Includes application. ?
No estimate.
"Shallow" plowing.
"Deep" plowing.
Guard service, no area
basis.
No estimate.

No estimate.
Computed equivalent
based on EPA cost/10 acres.
Ho estimate. " *
 Two Weeks of Hater Fixation                  $
 Long Acting Stabilizer
 Corn Removal
 Other Crop Removal
 Earth Removal  (Grader)
 Earth Removal  (Front End Loader)
 Earth Removal  (Manual Labor)
 Field Sod Removal
 lawn Sod Removal
 Vacuum!zed 'Sweeper for Streets
 Fire Hosing
 Homes
 Population Monitoring & Decontamination
 Evacuation,  Including Room, Board.
  Transportation and Personnel??! P-  12-3)
 Lawn Resodding
 Topsoil Replacement

 Erosion Control

 Fertilizer + Seed (Materials Only)
 Temporary Storage Sites  (Except Land  Cost)
 Plowing
  25 cm
  1  m.  Tilled Land                .           .
  I  »,  Pasture. Including Deseeding11' p> lz'"'
 Surveillance (Based on Periseter Length)

Conercial Areas
Disposal  (1000 Miles  of Transportation.
  2*  Soil  Rtwoval)
Biobarrier (labor and Materials)
Fence (Based on Perineter Length)

Present Value of Future Surveillance


 * T,I-  '— EPA Cutdance SuwaryJlMort.0"Table VI-?.  "OecontMilnation Costs."  EPA qiven in $/acre converted to $/ta2 for
               The EPA document includes cost  estimates for sows treatment Measures not used in DOE esttnates.
               Include overhead (251). loss  of efficiency due to protective clothing (304), workmen's co^>ensat1on and social
              »J. except for land reclamation  costs which do not require protective clothing and include only overhead and
         security.   All unit costs are rounded to the nearest $500.                                       jr    .      «no
  'Cott (estimate dues not «SSUK any burden.

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Nevertheless, the table is a helpful point of departure for a discussion  of
the reasons for the differences between the cost estimates of DOE and  EPA.
The estimates differ by a factor of about 3 or less, except fpr lawn resodding
(where the EPA estimate is for seeding while the DOE estimate is based on
application of sod) and fencing (where the basis for the EPA estimate  1s  not
specified'and DOE assumes use of a high chain-link fence).  The differences
noted in Table 14 do not account for the more substantial  differences  between
the EPA and,the DOE estimates of overall treatment costs per unit of area.
      In the Guidance Summary Report, (n> section 2, p. 17) n is noted that
"A minimum cost of $500 per acre [$123,500/km2] has been assumed for estimating
the costs which may be incurred in bringing all areas above the designated
level into compliance."  This figure is nearly two orders of magnitude smaller
than the minimum DOE'estimated costs/km2 indicated in Table 13.  The major
differences between the DOE estimated costs/km2 and the EPA's $500/acre
minimum estimate are the treatment assumed and the associated activities
considered.  The EPA minimum estimate includes only initial radiological
surveillance, application of a short-term soil stabilizer, and revegetation
with grass, although the EPA presents unit cost estimates for.a broad  range
of other treatment alternatives (11» Table VI-2).  The DOE estimates,  as
discussed in the preceding pages, include as essential actions:  evacuation
and monitoring of the human population from the affected site, radiological
samples and site surveillance, site decontamination, temporary and final
disposal of any contaminated soils and vegetation removed from the site,
land reclamation, production losses due to interruption of economic activities,
and—where decontamination is not feasible—site stabilization, real estate
acquisition, and permanent relocation of population.
                                     11-24

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REFERENCES
     i    •                                  .
 1.  U.S. Nuclear Regulatory Commission, Calculation of Reactor Accident
     Consequences.  Appendix VI to Reactor Safety Study.U.S; Government
     Printing Office, pp. 12-3 through 12-12, October 1975.

 2.  J. F. £line, G. M. Holter, W. H. Rickard and E. L. Klepper, Experimental
     Design for Demonstration of Bio-Barriers Placed in a Simulated BuriaT
     Trench.BNWL-2035, Battelle, Pacific Northwest Laboratories, Richland, WA
     99335, May 1976.

 3.  United States Department of Agriculture, Agricultural Statistics 1976.
     U.S. Government Printing Office, Washingtoni DC, 1976.

 4.  Raymond W. Goldsmith, ed.. Institutional Investors and Corporate
     Stock—A Background Study.  National Bureau of Economic Research,,
     Columbia Uni versity Press, New York, 1973.

 5.  United States Department of Commercea 1974 Gensus_ of Agriculture.
     U.S. Government Printing Office, Washington, DC,.1977.~~

 6.  United States Department of Commerce, County and City Data Book 1972.
     U.S. Government Printing Office, Washington, DC, 1973.

 7.  United States Department of Commerce, 1970 Census of Population; Detailed
     Character!stics, United States Summary.   U.S. Government Printing Office,
     Washington, DC, 1971.~~
 8.  J. R. Young, Procedures for Estimating Nuclear Fuel Cycle Costs.
                  "~~!i, Ri
     99,352, 1977.
BNWL-2210, Battelle, Pacific Northwest Laboratories, Richland, WA'1
 9.  Tri-State Motor Transit Company, Freight Tariff Number 1070-A.
     Docket MC 109397, p. 5, effective July 26, 1977.

10.  Final Generic Environmental Statement on Use of Recycle Plutonium in
     Mixed Oxide Fuel in Light Water Copied Reactors.8  U.S. Nuclear"
     Regulatory Commission, Vol. 4, p. XI-29, August 1976.

11.  United States Environmental Protection Agency, Proposed Guidance on
     Dose Limits for Persons Exposed to Transuranium Elements in the General
     Environment:  Summary Report.  Washington, DC, September 1977.
                                    11-25

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   APPENDIX A
SITE DESCRIPTIONS

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                                  APPENDIX  A
                               SITE  DESCRIPTIONS

      Since  the analysis of  impacts  is  presented specifically for each  refer-
ence  site,  the site-specific variables are given  here as simply and as
explicitly  as possible.  A  modified outline format allows easy identification
of the reference sites and  quick comparisons of factors across sites.
      The site descriptions  included in this section served as the basis for the
development of site-specific decontamination plans (Appendix C) and impact
analyses (Section II and Appendix E).  The sites  were selected 1) to include
the land types deemed importants 2) to occur in different important biomes,
and 3) to be we!1-documented.
      Each site description  that follows includes  all information needed to
identify detailed decontamination steps to be used as a basis for .analysis
of the site.  Specifically  mentioned are characteristics.which affected the
selection of alternative decontamination techniques and the rate at which
the decontamination effort  might be expected to be accomplished.  Analyses
were  conducted for each site on the alternative assumptions that 1-km  and
10-km  areas were found, after the hypothetical contaminating events, to
require remedial treatment.

REFERENCE SITE ONE
Topography:  The area is a  floodplain.  Ravines are the principal  feature to
     the west and east of the floodplain.   The elevation is approximately
     1000 ft (300 m) above  sea.level.   A major river flows next to the acci-
     dent site.
Climate:   Rapidly changing weather;  the area is located midway between two
     distinctive climatic zones (humid-east and dry-west).   The average
     temperature is 53°F (12°C).
Rainfall:   Average annual  rainfall:   30 in.  (76 cm).
                                     A-l

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Vegetation:  Native grasses and shrubs, with ash, elm, .and cottonwood trees
     along bluffs.
Land Use;  Within a 10-mile (16-km) radius of the accident site, 70% of the
     land area was assumed to be in farms.  A breakdown of the area into land
     types follows:
                          Corn Fields      - 37%
                          Hay and Soybeans - 14%
                          Idle Farmland    - 25%
                          Pasture Land     -  7%
                          Forest           -  3%
                          Population Areas - 14%
Population Distribution in Cleanup Areas:
                                 2                                      •
                         Area (km )     Population
                            1.0              15
                           10.0            5475
Description of Contaminated Area:
  •  Depth Profile - All plutonium was assumed to be located on or near the
     surface, since a fresh deposition was being considered.
  •  Isotopic Mixture - (wt%)
          238r
          239
          240
          241
          242
          241
JPu  -   1.4%
 Pu  -  58.0%
 Pu  -  24.0%
 Pu  -   9.0%
 Pu  -   4.9%
 Am  -   2.4%
                                    A-2

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  •  Areas to be Decontaminated -
                        Land Type
                    Corn Fields
                    Idle Farmland
                    Hay and Soybeans
                    Pasture Land
                    Residential Area
                    Commercial Area
                    Forest
        o
Area (knr)
1.0
0.37
0.25
0.13
0.11
5 Homes
0.05
0.09
10.0
3.70
2.50
1.30
0.60
1.40
0.20
0.30
REFERENCE SITE THO
Topography:  Moderate variation in elevation, with ground elevation 0-40 ft
     (0-12 m) above sea level.
Climate;  The mean daily maximum and minimum air temperatures during the
     warmest month are 83°F and 64°FX51°C and 18°C), respectively.  Daily
     minimum temperatures for the coldest months average about 22°F (-5.5°C).
Rainfall and Humidity;  Average annual rainfall:  45 in. (114 cm).  Average
     relative humidity:  75%.
Soils;  Glacial Soils - sand and gravel (till and outwash).
Ground Water;  There is no danger that surface drainage from the accident
     site could affect public reservoirs, because of the low permeability of
     soils in the area and a ground water gradient sloping from the reservoir
     to the site.
Vegetation and Wildlife;  The area comprises mainly secondary-growth hardwood
     forests.  Hardwoods include beech, sugar maple, and birch* with hemlock
     also abundant.  Wildlife includes woodchucks, skunks, racoon, grey
     squirrels, and cottontail rabbits.  A wide variety of upland birds and
     sea birds Is present in the vicinity of the accident site.
                                    A-3

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 Population Distribution 1n Cleanup Areas:
                          Area (km )     Population
                              1.0           2269
                             10.0           8202
 Description of Contaminated Area:
   •  Depth Profile - Contamination was  assumed to be located  on  or near  the
      surface,  since a fresh deposition  was  being  considered.
   •  Isotopic  Mixture - (wt%)
           238,
          239
          240
          241
          242
'Pu  -   1.4%
 Pu  -  58.0%
 Pu  -  24.0%
 Pu  -   9.0%
 Pu  -   4.9%
          241Am -  2.4%
     Areas  to  be  Decontaminated  -
                         Land Type
                         Forest
                         Shoreline
                         Population
                            Area  (km  )
                            1.0   10.0
                            0.21   3.96
                            0.22   3.96
                            0.57   2.08
REFERENCE SITE THREE
Location and Topography;  Located between two mountain ranges.  The terrain
     around the accident site is f 1 at-to-ligilt-rolling at an elevation of
     130-280 ft (40-85 m) above sea level.  Rainy winters are typical, with
     fair summer, spring, and fall seasons.
Climate;  Temperatures are greater than 90°F (32°C) on 80 days/yr, and less
     than 32°F (0°C) on 32 days/yr.
                                    A-4

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Rainfall and Humidity;  Average annual precipitation:  16 in.  (41  cm).
     Humidity is greatest in the winter (88% average), compared with 48% in
     the summer.                            _
Soils;  Hard-to-very-hard-silts, and silty clays with dense-to-very-dense
     sands and gravels.
Surface and Ground Water;  The area is bounded by well-defined drainage
     courses and natural gullies that intercept surface runoff .from the
     higher surrounding terrain.  Unconfined or semiconfined ground-water
     conditions occur in this area;  ground-water levels are about 157  ft
     (48 m) below the ground surface.
Vegetation and Wildlife;  Vegetation is predominately bunchgrasses and
     various other grasses.  Mammals in the area include ground squirrels,
     jackrabbits, coyotes, badger and skunk.
Land Use;  In a 5-mile (8-km) radius from the accident site, land is
     exclusively agricultural.  Grazing land dominates, with some field
     crops and orchards.  No dairy cattle are located within the 5-mile
     radi us.
Population Distribution in Cleanup Areas;
                                ..'2
                         Area (km )
                       7    1.0
                           10.0
                            Population
                                39
                               120
Description of Contaminated Area;
  •  Depth Profile - All plutonium was assumed to be located on or near the
     surface, since a fresh deposition was being considered.

  *  Isotopic Mixture'- (wt%)

          238n..
          239
          240
          241
          242
          241
Pu-
'Pu-
Pu -
Pu -
'Am-
58.0%
24.0%
 9.0%
 4.9%
2.4%
                                     A-5

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•  Areas to be Decontaminated -
Land Type

Pasture Land
Field Crops
Orchards
Irrigation Ditches
Residential Area
Area (km2)
1.0 10.0
0.58 5.80
0.31 3.17
0.07 0.70
0.03 0.30
0.01 0.03
                                  A-6

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APPENDIX B





 SAMPLING

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                                  APPENDIX B
                                   SAMPLING

     The sampling scheme presented in this section was developed solely to
provide a basis for estimating costs in the analysis of the three hypotheti-
cal^ contaminated reference sites discussed in this, report.  While the scheme
was designed to be consistent with the requirements of the Guidance, it should
not be considered in any way a guide for actual sampling programs for real inci
dents.  Sampling programs for use in such cases would have to be designed for
the specific circumstances of those incidents, including such variables as
site location, land types, involved meteorological conditions, and precipita-
tion.  Following the Guidance, it was concluded that the sampling scheme would
need to:
  •  Define those land areas in which the contamination exceeded.the soil
                                o
     screening level (0.2 u Ci/m  ).
  «  Provide a basis for determining those areas  in which dose rates to
     human occupants would be expected to exceed  1 mrad/yr  to the pulmonary
     1ung or 3 mrad/yr to the bone.
  •  Provide a basis for choices  among possible remedial treatment methods.
  •  Assess the  extent of residual  contamination  following  remedial  treat-
     ment of the affected areas.
     Three factors  were considered  in costing:  1)  labor needed  to collect
 the  samples, 2)  laboratory analysis of the samples, and 3)  power supply  for
 the  air samplers.   Equipment  needed for  sampling  (e.g., portable alpha meters,
 FIDLERs, Ge(Li)  vans,  and air samplers)  was  assumed to be  available  at nominal
 or no  cost.  A labor cost of  $2.50/sample or survey reading was  used,  based
 on the assumption  that it would take two monitors 10  min to obtain one sample.
 This cost  may  seem high, but  it allowed  for  time  to move to the  next sampling
 location.   Analysis of all  samples  (soil, air, vegetation,  foodstuff,  urine,
 and  animal  feces)  was  assumed to cost $100/sample.  These  analyses would give
                                       B-l

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 the isotopic breakdown necessary for dose calculations.  Several particle-size
 fractionatiori studies of air samples were also assumed to be necessary for dose
 calculations.  Power lines were assumed installed for the operation of air sam-
 plers in the affected areas at costs of $3/ft ($10/m) for lines installed above
 ground and $10/ft ($33/m) for underground installation.
      For most aspects of the sampling program, it was assumed that the number
 of samples required, and therefore the cost, was sensitive to the size of the
 affected areas but not to other differences in the areas.  While this is con-
 trary to expectations for real  incidents, as noted above, it was considered an
 appropriate simplification for the kind of analysis reported here.   Two excep-
 tions  to this simplification were made.   Numbers of samples, and costs, for
 monitoring of the human population and for analyzing possible contamination of
 foodstuffs were estimated specifically for each  site and  for the ultimate
                      2          2
 assumptions that 1  km  and 10 km  required remedial  treatment.   A summary of
 the assumed sampling requirements is  presented in Table B.I.
     The proposed EPA Guidance  states  (page  14 of Annex V)  that  "acceptance
 criteria which  allow a  maximum  chance  of  error of 5-10% are  generally  con-
 sidered  appropriate."   It is  assumed that  this statement  refers  to  the two
 types of decision errors  that could be made:   first,  deciding  that  remedial
 action is required when that  is  actually not  the  case;  and second,  deciding
 not  to take remedial action when  such action  should  be  taken according to  the
 guideline.   By specifying acceptable probabilities for  these two errors, it is
 possible  in  a real situation  to estimate the  number of samples that should be
 taken to  detect a contamination level greater than the Guidance value.  The
 approximate  numbers of samples given in Table B.I, however, were not derived
 on the basis of any specification of the two  decision errors because the
 Guidance  gives no indication of the statistical test criteria for determining
whether or not Guidance limits have been exceeded.  Different test criteria
would result in different requirements for numbers of samples.
                                     B-2

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TABLE B.I.    Approximate  Sampling  Requirements  for.  Delineating Areas  Needing
                   Remedial  Treatment  and  Assessing Treatment.Adequacy(a)
                    Definition af Areas Exceeding
                      Soil Screening Level(o>      ~

                1. Instrument Ground Surveys
                   along Radii

                   •  FIOLER
                   •  ALPHA
                   •  Ge (Li)

                2. Soil Samples along Radii

                3. Profiles for Depth Characterization

                4. Soil and Instrument within
                   Sampling Units

                   •  Ge (Li)
                   •  Soil

               	Dose Estimation	

                5. Soil and Instrument Surveys

                   •  Ge (Li)
                   e  Soil

                6. Air Samples(d)-

                7. Vegetation

                8. Foodstuffs

                 " •  Site 1
                   •  Site 2
                   •  Site 3

                9. Population (Human) Monitoring

                   •  Site 1
                   •  Site 2
                   •  Site 3

               10. Water and Sediments

               11. Wildlife and Domestic Animals

                      Post Cleanup Sampling	

               12, Soil and Instrument
                   •  Ge (Li)
                   •  Soil

               13. Air Samples

               14. Vegetation

               15. Foodstuffs

                   •  Site 1
                   •  Site 2
               .    •  Site 3  .

               16. Water and  Sediments

               17. Wildlife and Domestic Animals

               18. Population (Human) Monitoring
                   •  Site 1
                   •  Site  2
                   •  Site  3
     .Hypothetical Cleanup Area
      1 kaf-    :          10 km
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DEFINITION OF AREA CONTAMINATED BEYOND THE SOIL SCREENING LEVEL
     Meteorological conditions at the time of any real contaminating incident
would be considered in planning the initial ground surveys.  For purposes of
this analysis, it was assumed that the ground was surveyed on radials running
out from the accident site at 15° intervals (Figure B.I) as necessary to define
                                                        2
the boundaries of the area contaminated beyond 0.2ii Ci/m .  One Ge(Li) scan
was assumed for each 10 portable instrument readings, the total numbers of each
test approximating those shown in Table B.I.
     In the assumed sampling program, FIDLER and Ge(Li) detector readings were
taken in the field as a check on the validity of'alpha readings rsince :the
FIDLER and Ge(Li) techniques are sensitive to the 60-keV x-rays from    Am,
rather than the plutonium alphas.   Soil particle-size fraction studies were
assumed on several soil samples to estimate the distribution of contamination
in the various soil-size fractions.  This information would be necessary for
dose calculations.
               FIGURE B.I.
Pattern of Radials for Sampling for a
Hypothetical  Contaminating Event
                                     B-4

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      Soil  profiles were assumed taken at various distances frbnv the accident
 site and for various land types encountered.  The depths to which such profiles
 would be required in a real  incident would depend upon.,the, length of "time.,.,,"
 between the accident and the takingrof samples and upon sthe nature of .any dis-
turbance, which .might have occurred during this period.
                                                         2
      The final assumed step  in determining the<0.2u Ci/m> boundary involved
 dividing the: land area into  sampling units at the approximate boundary.  Within
 these units additional soil  and Ge(Li) readings were assumed to be taken.  Sta-
 tistical analysis/of these data was.assumed to involve,such parameters as the
        •      	  ..•.;•,    •..---..   ,  ,-.-..     -   , -      .  . -   A
 arithmetic mean,  median,..proportion of observations above p.2u  Ci/m , largest
 concentration obtained, and  spatial orientation of the samples.

 DOSE ESTIMATION                   \       .,- ,;.   ^;   ;   ,  ,   ,       s.
      The next steps in the assumed sampling were the division of the area' con-
                                      p
 taining levels greater than  0.2u Ci/m  into activity strata and the collection
 within these strata of samples of water, sediment,  foodstuffs,  vegetation, air,
 small  mammals, and additional  soil.  The number of samples and  portable survey
 readings assumed  needed in this phase are presented in Table B.I.
      Since inhalation may be the primary pathway for the introduction of
 Plutonium into the body, air monitoring was assumed necessary,  especially
 during decontamination.procedures.  Several portable air samplers  were assumed
 to  be placed upwind (for.controls) and downwind from the accident  site to help
 locate any immediate resuspension problems that would need to be considered
         ..            \    •              "    •.'•...-.•'  .•:''. • '.. .""'•',.,''
 before survey teams moved in.   Particle-size analysis, was included to
 assist in  the determination  of dose to the lung from,respirable soil  particles.
      It was assumed that following initial  characterizations air samplers were
               . - -     •.''••-                     .      o
 placed every 500  ft (152 m)  along the perimeter of the 0.2y  Ci/m  boundary.
 Filters were assumed to be changed every 2 wk for up to 1 yr.
      The samplers  would provide data  on the air concentrations  of  contaminants
 leaving the area  due to the  resuspension from ground contamination in the
 affected area and  decontamination operations^       ;  ' ,:    1
                                      B-5

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     Additional air samplers were positioned withirv the perimeter during
cleanup for the determination of possible occupational risks.  Approximately
25 samplers/km2 were assumed necessary for the 10 km2 areas in this analysis;
10 samplers/hectare were assumed needed for the 1 km  areas.  Additional air
samplers were also considered to be used in the vicinity of temporary contami-
nated soil storage mounds.
     The following types of samples were* assumed collected to help to estimate
the dose to man from the ingestion pathv/ay:  1) crops such as wheat, corn,
potatoes, tomatoes, etc; 2) water for humans and farm animals; 3) milk, milk
products; 4) hair and feces of farm animals and pets; and 5) liver and muscle
of cattle, chickens, and other edible farm animals.  About 20 samples per farm
                    i)
within the 0.2y Ci/m  boundary were assumed to have been collected.  In Table
B.I, the number of samples shown under "foodstuffs" is specific to each site
and assumes 20 samples per farm; the numbers of farms in the affected areas
were estimated by dividing the size of the areas by the average-size farm for
the respective regions of the country.
     It was assumed that the population within the areas designated for reme-
dial treatment would undergo a personnel survey.  Table B.I shows for each
reference site the estimated number of samples requiring analysis, based on
the population within the affected area.  Follow-up sampling was considered
necessary for persons who showed positive results.
     Sediments of ponds and rivers in the contaminated areas would be expected
to accumulate radionuclides.  Accordingly, water and sediment samplers were
assumed to be collected, as indicated in Table B.I.

POST CLEANUP SAMPLING
     Post cleanup monitoring was assumed to be handled by dividing the decon-
taminated area into units and taking Ge(Li) scans and soil samples within each
unit.  Included were several soil profiles needed to determine whether soil
had been removed to an adequate depth.
                                      B.-6

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     Post cleanup monitoring was also assumed to include samples of air, vege-
tation, foodstuffs, water, sediment, and animals.  Sampling of vegetation was
considered to be continued for several years after cleanup to ascertain that
plants were not taking up any transuranic materials that might have escaped
the decontamination processes.  As shown in Table B.I, post cleanup monitoring-
of the human population within the affected areas was also assumed.
                                    B-7

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             APPENDIX C
REFERENCE DECONTAMINATION PROCEDURES

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                                  APPENDIX C
                     REFERENCE DECONTAMINATION PROCEDURES

      The EPA Guidance specifies no procedures for use in stabilizing or
 decontaminating areas impacted by releases of transuranics...  A variety of
 ways  could  be proposed to bring contaminated areas into  conformance with
 the Guidance.   As  a  basis for assessing  in this  analysis the  costs  and other
 impacts  of  compliance with the Guidance  sets of  procedures  were selected
 which were  judged  to be realistic,  workable, approaches to the removal  or
 stabilization  of contaminated soils following an  accidental release of tran-
 suranics.   It  is unlikely that the  selection of alternative procedures  to
 achieve  the same ends  would have  produced  large differences in  costs or other
 impacts.  However, the procedures described  here  were assumed for the  purposes
 of illustratory analysis  only.  The labor requirements and timing assumptions
 for these procedures,  used as  a basis for  cost estimates, are summarized in
 Table C.I.

 GENERAL APPROACH
Area Restriction, Stabilization, and Evacuation
     A series of steps was assumed, solely as a basis for analysis,  to be
taken  following each hypothetical contaminating event:
  • The area of suspected contamination was defined.
  • Traffic into and out of this area was restricted.
  •  Individuals in the area were alerted to take appropriate  precautions  to
    prevent personal exposure.
  • Monitoring teams, equipped with portable equipment,  were  dispatched to
    define  the area  which would probably require  remedial treatment.
  • People  in the  probable treatment area  were evacuated, examined  for
    radiological contaminants,,and  housed  in temporary evacuation centers
                                    C-l

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TABLE C.I  Man-Hour Estimates  and  Removal  Deadlines
for Decontamination
Land Area Man-hr/km2
1.



2.
3.
4.
5.
6.


7.
8.
9.
10.
11.
Cropland (cornfield)
- Corn Removal
- Soil Removal
- Total
Grazing Land
Pavement
Forest
Ditches
Roof Areas
- Sloped
- Flat
Lawns
Homes
Population Area
Orchards
Shoreline

600
2,200
2,800
3,200
500
25,800
8,600

1,300
6,500
11,600
37,500
16,200
8,600
15,600
Cleanup
Deadline

1 month
1 year

1 year
1 month
1 year
1 year

T month
1 month
1 month
1 month
1 month
1 year
1 year
                          C--2

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       (e.g.,  nearby schools  or community centers).   They were maintained in
       these centers until  survey teams  concluded  that it was  safe  for them
       to  return to  the  area  or until more permanent  housing was  arranged.
   •   Areas identified  as  contaminated  were treated  where appropriate with
       water spray and later  with  a  longer-acting  stabilizer to control the
       spread of the  transuranic materials.
 Removal of Contaminated Soils

       Where removal of soils was assumed  to be a  part of  the remedial  treat-
 ment  procedure, the following steps were included as a cost basis:
   •  Soil was scraped to a depth of 5 cm.
   «  Soil was hauled by dump truck to temporary storage sites (about 1 site
      for each 2-km  contaminated section).
   •  Soil was bulldozed into temporary mounds for storage,  and the mounds
      were treated with  soil  stabilizers to prevent resuspension  or erosion.
   •  Within about 1 yr, the  soil  in the mounds was packaged  in 55-gal (208-&)
      drums and shipped  in  unshielded vans an  average of 1000  miles (1600 km)
      for ultimate disposal in  Federal  disposal  sites.
      These steps  were based  upon  the expectation  that the transuranic mate-
 rials would be concentrated  in, the  top  few cm of  soil  in  recently  contaminated
 areas.   Fresh  depositions  would migrate only  to a limited depth, according
 to research on the  subject.  Jakubick,(1^ for instance,  predicted  a migra-
 tion  rate  of only 0.8 cm/yr  in  soils studied  in Germany.  Specific cost
 bases  were taken from BNWL-2210,  (2) the  Tri-State Motor  Transit Company,
 and GESMO.(4'        *
 Plowing of Contaminated Soils

     Plowing is a method by which contamination can essentially be buried
 in place,  eliminating the need for costly final burial.   Plowing was con-
sidered here as an alternative decontamination method for cropland and
grazing land.
                                     C-3

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     Plowing to depths of 10 in. and 3 ft (25 cm and 0.91.m) was considered
here.  Ten-inch plowing was 'assumed to.be done with a 100-hp farm tractor and a
standard 7-bdttom farm plow.  One pass with the plow at a rate of approxi-
mately 125,000 m2/day(a) was predicted to yield a residual fraction of 20%.
Assuming one worker per plow, an effort of approximately 8 man-hr/km  was
estimated to be required.
     Deep plowing to 3 ft  M m) can bury approximately 95% of the surface
contamination deeper than  2-3 ft (0.7 m),(6) which would allow uptake of
contamination from only deep-rooted plants.  Deep plowing was assumed to be
done by two large crawler  tractors pulling a moldboard plow, capable of
36-in.-deep furrows.(6'7)   A crew of four was  considered to be necessary:  two
tractor drivers, one  person at  the controls of the  plow, and one  laborer.
About  1 acre  (4000 m2) was estimated to  be plowed  per hourv   with an effort
of approximately 4 man-hr  per acre or  1000 man-hr/km .
Post-Decontamination Survey
      Final  release  surveys were considered  to be necessary for  all  decon-
taminated areas.   Steps included resampling,  primarily  by soil  and air  moni-
toring with some portable instrument surveys.   Vegetation and foodstuff
 sampling was considered to be necessary to assure that uptake by plants
 did not present a risk to the public.   Estimates of the number of samples
 needed for the final release survey are presented in Appendix B.

 APPROACHES SPECIFIC TO LAND TYPES
      The appropriateness  of various decontamination methods would vary with
 the types of land or land uses affected.  Descriptions of methods assumed
 for various land types and uses in this analysis are presented below in an
 outline format for easy reference.  These descriptions  include rate factors
 needed to make consistent cost estimates for  the decontamination methods
 assessed in this report.

  S*Jp. Tvergyak, 1978,  Extension  Economist,  Coulee  Dam,  WA;  private  communication.
  ^Approximately 20% of  the original  surface  deposition would  remain.within  the
     top  1 cm and be  available for resuspension.
                                       C-4

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      For those methods that involve soil removal, estimates of man-hr require-
 ments are included.  Manpower needs for transport of soil to a temporary stor-
 age site are described in Appendix D.  For final burial, manpower needs were
 taken from BNWL-2210.     Labor requirements for monitoring are presented in
 Appendix B.   Supervisory personnel are accounted for in the discussion of the
 25% burden of the unit cost (text Section II).

 DECONTAMINATION OUTLINE
  I.   Cropland
       A.   Stabilization
           A  road-type sprayer was assumed used to apply the  initial  water-
           spray stabilizer.   After the crop  was cut  and removed,  the soil
           was expected to be covered  with  a  long-acting stabilizer.   A
     '.-••-•  9000-gal-capacity  (34,000-£) tanker truck  with spray  bars  and  a
           five-man  crew was  estimated to  be  able to  apply the stabilizer at
           a  rate  of 
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         The crop was assumed to be cut and removed in one operation, using
         a harvesting-chopping machine.  With a three-man crew, <30 tons
         (27 tonne) of cropland cover was estimated to be removed per hr.
         This rate depended upon a mix of crops being cut since, for example,
         corn could be removed at a rate of 1-1.5 acres/hr (4000-6000 m /hr)
         while hay could be removed at approximately five times that rate.
         The freshly cut crop was considered to be hauled to a temporary
         storage site where it was placed in 55-gal (208-5,) drums and
         stored until shipped for permanent burial.  An effort of
         ^00 man-hr/km2 was estimated to be required for crop removal.
      D.  Soil Removal
      E.
Where necessary, a large road grader (12-in. or 30-cm blade) was
assumed to be used to remove the soil down to an appropriate
depth.  With a three-man crew, the grader could remove soil at a
rate of 4.0 equip-min/103 ft2/5) which is equivalent to an effort
of 2200 man-hr/km2.  A front-end loader (5-yd3 or 4-m  capacity)
was considered to be used to clean up the windrows left by the
grader.
Plowing
Where plowing is considered in this analysis, it is assumed that
it was accomplished as described under "General Approach," above.
II.   Grazing Land
      A.  Stabilization
          The initial water-spray stabilizer was assumed to be applied
          within 24 hr of the accident, using tanker trucks with spray bars,
          Water was considered to be applied on alternate days until  the
          long-acting stabilizer was distributed.  One-tenth inch (0.25 cm)
          of water was estimated to be applied at a time,  the soil  stabili-
          zer was assumed to be applied to affected areas within 1 month.
                                     C-6

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      B.  Characteri zati on
          Refer to IV-B.  In additions monitoring of cattle (feces and
          tissue analyses, plus milk analysis for dairy cows) was assumed
          necessary.
      C.  Removal
          A self-propelled sod machine (20-in. or 51-cm blade) was expected
          to be used on the grazing land.  When removing soil  to a depth of
          2 in. (5 cm), approximately 10,000 ft2/hr^ could be removed.
          With a three-man crew, ^3200 man-hr/km2 would be necessary to
          complete removal.   In areas not accessible to the sod machine,
          either a front-end loader or manual methods of removal were
          assumed used.  Deadline for removal was set at 1 yr.
III.  Forest Land
      A.   Stabilization
          It was assumed that access to the forest was controlled for
          several  months after the accident to allow rainfall  to wash
          contamination into the forest mat.
      B.   Characterization
          Soil  and vegetation samples were assumed to be taken periodically
          during the isolation phase to determine whether contamination  was
          being washed  into  the forest mat.   Air monitoring  stations  were
          also  posited  on the periphery of the forest to identify any resus-
          pension  problems.
      C.   Removal
          It was assumed  that the  forest mat was removed where  it was
          contaminated, leaving most of the trees standing.  Half of the mat
          was considered  to be removed by a small front-end loader  (1.5 yd3
          or 1.2 m ' capacity) and  half by manual methods.  A front-end
          loader with a two-man crew would require an effort of 8600 man-hr/km2/5^
          while manual shoveling with a four-man crew would requ-ire
  D. Jenks, 1977, Redeturf, Inc., Aurora, Oregon; private communication.
                                    C-7

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          43,000 man-hr/km2/5)  Overall, an effort of 25,800 man-hr/km  was
          estimated to be required.  Deadline for cleanup was 1  yr following
          the accident.
IV.  Populated Area
      A.  Stabilization
          In populated areas, it was anticipated that the initial  water-
          spray stabilizer was applied within 24 hr of the accident.   Applica-
          tion was by tanker trucks with spray bars, and occurred on
          alternate days until a long-acting stabilizer was spread.  A
          smaller capacity tanker (2000 gal or 7600 A with one spray  nozzle)
          was assumed to be used to apply the stabilizer to more confined
          areas of the population center.  Initial water-spray and long-
          acting stabilizers were assumed not to be applied to pavement or
          roof areas.
      B.  Characterization                                             *
          Every home in contaminated areas was assumed to require an  interior
          and exterior survey.  The exterior survey involved a check  of the
          roof and chimney area and spot checks of the walls.  Interior
          surveys included a survey of entrances, filtering systems,  and
          easily accessible surfaces (tables, floors, etc.).
          If no contamination was found, a complete survey was estimated to
          require an average effort of 4 man-hr^a' per three-bedroom home.
          If contamination was found during the survey, it was expected that
          monitors would need to do a more complete survey requiring approxi-
          mately 8 man-hr.^a'
      C.  Removal
           1.  Pavement
               Rough-textured concrete or asphalt roads were assumed to be
               cleaned up using a vacuumized mechanical sweeping machine
   J. R. Berry, 1977, Pacific Northwest Laboratory, Richland, WA; private
   communication.
                                    C-8

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3.
    traveling  at  a  speed of 4  1/2 mph  (7.2  km/hr).  Two  passes
    were estimated  to be required to get  a  residual fraction of
    less than  10%.  A work rate of 2.8 equip-min/103 ft2^
    and a one-man crew would yield approximately 500 man-hr/km2.
    Removal deadline was set at 1 month,  except for evacuation
    routes that required immediate cleanup.
2.  Roofs
Firehosing  (3/16- x 9/16-in. or 0.48- x 1.4-cm orifice;
120 psi or  8.4 kg/cm2; 0.12 gal/ft2 or 4.9 £/m2)^5^ with
three persons per nozzle was the assumed method for removing
particles contaminated with transuranics.  Firehosing of
sloped roofs would require 2.4 nozzle-min/10   ft ^ ' or
26 nozzle-min/103 m , *5' or an effort of 1300 man-hr/km2.
Firehosing  of flat tar and gravel roofs would require
12 nozzle-min/103 ft2^ or an effort of 6500 man-hr/km2.
For this study, roof areas were assumed to include 50% sloped
roofs and 50% flat tar and gravel roofs; therefore, an effort
of 3900 man-hr/km2 was estimated.
Roofs were  assumed,to be decontaminated prior to lawn and
home exterior cleanup so that contamination displaced from
the roof would be removed in later decontamination-phases.
Some roof runoff might run into storm sewers and from there
go either to a sewage treatment plant or a nearby stream or
river.  For this reason, sludge was assumed to be monitored
at sewage treatment plants and packed into 55-gal  (208-&)
drums for burial if determined to be a risk.  Runoff into
streams and rivers was considered to be checked by monitoring
stations along these waterways.  Removal  deadline was 1  month.
Lawns                                      .
Lawns were assumed decontaminated using sod machines;  areas
not accessible to the self-propelled machine used  for the
grazing land (refer to II-C)  required use of a smaller machine
                         C-9

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               with a 12-in.  (0.3-m)  blade and a two-man  crew.   The average
               effort required for lawn removal  was estimated to be
                               2 (9}
               11,600 man-hr/km .v '   Removal  deadline was  1  month.
           4.   Home Decontamination
               In a 1-km  area, homes were considered to  take up 23% of the
               land area (2.5 x 106 ft2 or 2.3 x 105 m ).   An average home
               was assumed to occupy  ^2.00 x 103 ft  or 190 m ;  therefore,
                                                 2
               about 1250 homes would occupy 1 km .  At a cleanup rate of
               30 man-hr/home,'a'  an  effort of 37,500 man-hr/km   was estimated
               to be required for  home decontamination.   Each decontamination
               crew consisted of four persons.  Removal deadline was set at
               1  month.
      D.   Overall Cleanup Rate
          The  composition of a populated area  was assumed to  be  the follow-
          ing, based on  assumptions in WASH-1400:^°'
          1)  Lawn, fields               - 57%
          2)  Pavement                   - 20%
          3)  Roof                       - 23%
          4)  Home and other buildings   - 23%
          To obtain an estimate of overall effort for the decontamination of
          a populated area, the above percentages were multiplied by their
                                p
          corresponding  man-hr/km   values and  summed, yielding an assumed
                                    2
          effort of 16,200 man-hr/km .
 V.   Shoreline
      A.  Stabilization
          It was assumed that an initial  water-spray stabilizer was  applied
          within 24 hr of the accident,  using tanker trucks  with spray bars
          wherever possible.   Water was  considered to be applied on  alternate
          days until  the long-acting stabilizer was distributed.  The
U)
J. R. Berry, 1977, Pacific Northwest Laboratory, Rich!and, WA; private
communication.
                                    C-10

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       .   stabilizer was assumed to be spread directly on the shoreline, and
          all affected-areas were-considered to be treated within 1 month.
      B.   Characteri zati on
          In addition to preliminary monitoring to determine the extent of
          the affected area (the area above the guideline limit), soil core
          samples were assumed to be taken,to indicate the depth of soil to
          be removed where percolation or -soil movement/was suspected.
          Air monitoring stations located on fringe areas were posited  to
          identify possible resuspension problems  particularly during the
         'cleanup phase.
      C.   Removal
          Since the composition (clay, soils, sand, and gravel) and acces-
          sibility of a shoreline are highly variable, several methods were
          considered to be used in cleanup.  The following distribution of
          methods was assumed for this analysis:
          1)  Road grader (see I-C) - 25% of shoreline
          2)  Manual (see III-C) - 25% of shoreline
          3)  Small front-end loader (see III-C) - 50% of 'shoreline.
          To obtain an estimate of overall effort, the above percentages
                                                          2
          were multiplied by their corresponding man-hr/km  values and
                                                        2
          summed, yielding an estimated 15,600- man-hr/km .  The removal
          deadline for shoreline contamination was set at 1 yr.
VI.  Ditches
      A.  Stabilization
          It was expected that where water was flowing in a ditch, the
          source was diverted, if possible; stabilization then proceeded
          as in II- A.                       '        :
      B.  Characterization
          In addition to preliminary monitoring to determine the affected
          area (the area above the guideline limit), soil core samples were
                                    c-n

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VII,
VIII,
           assumed  to  be taken to  indicate the depth  of soil  and sediments  to
           be  removed.   Air  monitoring  stations were  considered  to  be established
           on  fringe areas to  identify  any resuspension problems, particularly
           during the  cleanup  phase.
      C.  Removal
     A small front-end loader  (refer to  III-C) was considered  to be
     satisfactory for removal  of material from broad areas; however, a
     backhoe was assumed necessary to reach confined areas.  Deadline
     for removal was 1 yr.
 Orchards
 A.  Stabilization
     Trees were assumed to be  sprayed in an effort to wash the contamina-
     tion into the orchard mat.  An earthen dam was considered to be
     built around the orchard  v/here needed to contain runoff from the
     spraying.
     Character!zati on
      B.
      C.
     It was assumed that, in addition to preliminary monitoring to
     determine the extent of the affected area, soil core samples were
     taken to indicate the depth of soil to be removed.  Air monitoring
     stations were considered established on fringe areas to identify
     any resuspension problems, particularly during the cleanup phase.
     Removal
     It was assumed that cleanup of the orchard mat was done entirely
     by a small front-end loader (refer to III-C) since larger areas
     would be available for maneuvering equipment in an orchard than in
     a forest area.  Deadline for removal was 1 yr.
  Rivers
It was expected that no attempt would be made to clean up river or
stream bottoms.  Patrol of the river was assumed to be necessary to
prevent water traffic in and out of affected reaches until the extent
                                    C-12

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of any possible risk was established.  Environmental sampling locations
to test water and sediments, including shorelines, were expected to
be established at locations such as dams and river bends downstream
from the affected area, where particulate settling could occur.  Sedi-
ments in settling basins at water treatment facilities near the affected
area were also considered to be analyzed periodically.  This type of
monitoring might be continued less frequently after the first year.
                               C-13

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REFERENCES

 1.   A. T. Jakubick, "Migration of Plutonium in Natural  Soil."  Transuranium
     Nuclides in the Environment. IAEA-SM-199/3, November 1975.  	""—~~~~

 2.   J. R. Young, Procedures for Estimating Nuclear Fuel  Cycle Costs
     BNWL-2210,  Appendix B,  Battelle,  Pacific Northwest  Laboratories',
     Rich!and, WA  99352, March 1977.
 3.   Tri-State  Motor Transit Company,  Freight Tariff Number  1070-A.
     MC 109397, p.  5,  effective July 26,  1977:	  	~——
                                                                      Docket


  4-   Final  Generic Environmental  Statement on Use of Recycle Plutonium in
      Mixed  Oxide Fuel  in Light Mater Cooled Reactors.U.S.  Nuclear Regula-
      tory Commission,  Vol.  4,  p.  XI-29,  August 1976.

  5.   W.  L.  Owen, W.  C.  Cobbin  and W.  E.  Shelberg, Radiological  Reclamation
      Performance Summary. Vol.  II.   Evaluation and'Condensation of  bata"?or
      Preplanning of Recovery Operations":Naval  Radiological  Defense Labora-
      tory,  USNRDL-68-71, San Francisco,  CA,  September  1967.

  6.   P.  E.  James and R.  6.  Menzel,  "Research  on  Removing Radioactive Fallout
      from Farmland." USDA, ARS,  Tech. Bull.  No.  1464,  1973.

  7.   R.  6.  Menzel  and P. E. James,  "Treatments for  Farmland Contaminated with
      Radioactive Material."  USDA,  ARS, Agricultural Handbook No. 395, 1971.

  8.   L.  E.  Bruns,  K. T.  Key and B.  A. Higley, Hanford Contaminated Sediment
      Stabilization Studies.  ARH-CD-640, Atlantic Richfield Hanford  Company,
      Richland, WA 99352, March 5,  1977.

 9.  W.  C.  Cobbin and W. L.  Owen, Development and Test of a Sod-Removal
     Procedure for Moist Lawns Contaminated by Simulated Fallout.  USNRDC-
     TR-965, Naval Radiological Defense Laboratory, San Francisco, CA,
     April  1966.

10'  Reactor Safety Study:   An Assessment of Accident Risks in U.S.  Commer-
     cial Nuclear Power Plants. Appendix 71. "Calculation nf $£*?+** ArHdent
     Consequences."WASH-1400, Nuclear Regulatory Commission, October 1975.
                                  C-14

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       APPENDIX D
UNIT COST DETERMINATIONS

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                                 APPENDIX A
                          UNIT COST DETERMINATIONS
BASIC COMPONENTS
     The basic components upon which unit costs were based are identified
in Table D.I.

                  TABLE D.I.  Basic Components of Unit Cost
  ;            1.  Equipment
              2.  Work Crews
              3.  Support Personnel
              4.  Supplies
              5.  Equipment decontamination
              6.  Transportation  to a  temporary  storage  site

      Equipment  for  decontamination operations was assumed  to  be  leased on  a
per  month  basis except for  the  vacuumized  sweeper, which was  assumed  to  be
purchased  because decontaminating it would be difficult  following  cleanup
operations.   For several  unit cost determinations  (e.g., manual  earth removal
and  home decontamination),  no equipment cost was included  in  the initial
decontamination phase because this cost added  insignificantly to the  total
unit cost.  Equipment costs for firehosing were  not  considered because the
equipment  was assumed to be available  from local fire companies.  Table  D.2
describes  the equipment  used in cleanup and lists average  costs  for daily
and  monthly leasing.
      Work  crews were assumed to include equipment operators and several
 laborers.   Standard union wages were considered  for these  workers - $10.85/hr
 for equipment operators  and $5.41/hr for general laborers.  Support personnel
 would include foremen and radiation monitors.   The assumption was made that
 one foreman would be required for every 50 persons involved in the.decontamina-
 tion operations, and one radiation monitor for every five persons.  The wage
 rate-was considered to be $10.20/hr for foremen  and  $7.56/hr for the  monitors.

                                     D-l

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     TABLE  D.2.   Equipment  Descriptions  and  Leasing  Rates Without

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
lype or tquipment
Water-Tanker Truck
Description
9,000-gal capacity
Crop Harvester-Chopper 2-row
Farm Tractor
Front-End Loader
Front-End Loader
Grader
Sod Machine
Sod Machine
Bulldozer
Dump Truck
Plow
Vacuumi zed Sweeper
100 hp
270 hp, 5~yd capacity
100 hp, 1-1/2-yd3 capacity
12-ft blade
200 hp, 20-in. blade
10 hp, 12-in. blade
320 hp
200 hp
7- bottom
17 hp
Monthly
$2,300
1,000
2,200
5,100
1,700
2,500
3,100
1,200
7,040
1,400
450
7,500(b)
Daily
$ 77
33
73
170
56
84
103
40
235
46
15

  a  Costs  were developed from a  cost estimating guide^  and  quotes  by sup-
    pliers,  in an  effort to  develop average costs  for the U.S.
 *  'Assumed  purchased.

      Supply costs included  in unit costs were for the long-acting soil  stabi-
 lizer,  asphaltic  emulsion,  and  fuels.   Costs  for  the long-acting  stabilizer
 and asphaltic emulsion  were obtained from Bruns,  et  al.(2)   Ninety  percent of
 the estimated unit costs  for the  long-acting  soil  stabilizer ($62,500/km2)
 were materials costs.   The  unit cost for water fixation  has  entirely  labor
 cost, due to  the  assumed  need for repetitive  application  (every other day
 for 2 wk).  Fuel  costs  used  were  $0.428/gal ($0.110/*) for diesel fuel and
 $0.60/gal ($0.16/£) for gasoline.

     Factors considered in the.decontamination of equipment  included costs
for labor and radiation monitors.   The time required to clean one piece of
equipment was assumed to be 1 man-day each for labor and radiation monitors.
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     Transportation to a temporary storage (burial) site was assumed to
involve costs for equipment (a dump truck) and truck drivers.  Estimated
costs ,at the storage site included equipment (bulldozer) and equipment
operator costs.     .                                     ;      . ,
     The unit costs for a temporary storage site, surveillance, population
monitoring, and land reclamation presented in Table II.2 of Section II do
not follow the basic outline presented in Table D.I.  The unit cost for the
temporary storage site included costs for the application of soil stabilizer
and for a guard.  One guard was assumed to be on each site for 1 day per
week for a year, patrolling the perimeter of the affected area and limiting
entrance to authorized personnel only.  The unit cost for population monitoring
included a portable alpha survey, nasal smears, and two urine samples per
person.  An analysis cost of $100/sample was used.
     Unit costs for land reclamation were provided for lawn resodding, top-
soil replacement, erosion control, and fertilizer plus seed.  Lawn resodding
included both material and labor cost; the cost of the sod  (U.S. average -
$0.93/m2) was approximately 99% of the total estimated unit,cost.  The unit
cost for topsoil.replacement also included a cost for materials and labor,
with the materials making up about 82% of the total.  The topsoil cost was
$5/yd3  ($6.5Q/m3), and the unit cost assumed replacement of  the top 2 in.
(5  cm),  of  soil  over an area of 1 km2.  The unit cost for erosion control
included application of a cellulose slurry ($200/acre or $49,400 km ) and
soil stabilizer ($125/acre or $30,900/km2).  The .material cost  represented
^50% of the  estimated unit cost for erosion control, with the remainder
being application  costs.  The unit cost  for fertilizer  plus  seed was  about
$200/acre  ($49,400/km2).  Labor for this  unit cost was  not  added because  it
was assumed  that this mixture could be applied at the  same  time,as erosion
control materials.
      Unit  costs for packaging and  transportation  of contaminated materials
were derived from  figures given in BNWL-221o'3'  and  by the  Tri-State .Motor :
Transit Company. v'   the cost of ..burial  at a  Federal repository .was taken
from ($60/ft3 or $i;70/m3) GESMO.^   The transportation distance  was  con-
sidered as 1000 miles for the reference  sites.   Cost estimates  were based
on the  following assumptions:
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    •  The waste container was a DOT Specification 17C 55-gal (208-n) steel drum.
       Fill  volume was assumed to be 7.0 ft3 (0.2 m3) per drum (approximately
       90% fill).
    •  Cost  of 55-gal  drum was assumed to be $20.
    •  Labor costs were based  on $10.00 per  man-hr and assumed 1  man-hr  to
       fill  and  load a drum into a  van (2 persons  at  30 min/person).
    •  Hauling charges were calculated on the basis of $0.98/mile ($0.61/km)
       one way for the 1000-mile (1600-km) shipment's).

 BURDENING

      All initial  unit costs  (see Table  II.2, Section  II) were burdened by
 overhead (25%),  loss  of efficiency due to  protective  clothing (30%), and
 workmen's compensation and social security (10%), except that the land reclama-
 tion cost did not include the 30% burden for protective clothing.  The 25%
 burden for overhead took into account all supervisory personnel, equipment
 maintenance,  and administrative costs.  The 30% burden for protective clothing
 was based on  loss of work time due to the necessity of suiting up and changing
 clothing several  times per day.

 SAMPLE UNIT COST CALCULATION
      The procedure used in calculating unit cost can be  best explained  by
 example.   The unit cost calculation for field  sod removal  is presented  in
 Table D.3.  Equipment needs (machine-days/km2)  were  determined from  equipment
 removal  rates.  Tahio n A. n*»aean*e-  4-u« m,^u-;v,«  j_	/i	2
Table D.4 presents the machine-days/km' for various pieces of
            One machine-day was equated to 8 machine-hr.
decontamination equipment.
Machine-days/km2 were'then multiplied  by  leasing costs  (Table  D.2)  to determine
equipment cost/km  .
     Crew requirements for the various decontamination operations are presented
in Table D.4.  For field sod removal, one machine operator and two laborers
were assumed to work 138 days (Table D.3, pt. 2).
                                    D-4

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         TABLE D.3.  Unit Cost Determination for Field  Sod Removal
1)  Equipment



2)  Crew

      •  Operator



      •  Laborers


3)  Support

      •  Foreman
4)  Supplies

      •  Fuel
5)  Equipment
     (Decon)
                                                                       Cost
                     138 mach-day
                        km
                          2
/   $103 A
I mach-day I
                                                           $14.214/km
           138 mach-day  /I man-.day\ /$86.80 \
                         ^mach-day j \ man-day J
                         1^
      •  Laborers


      •  Monitors


6)  Transportation

      •"' Equipment



      • ' Crew
Supplies
 (fuel)

Equipment
 (Decon)
           138 mach-day  /2 man-day\/$43.28  ]
                         \ mach-day j yman-dayy
                         kn>

                     1  Foreman (70 Days)   ^p^iiEday
      •  Monitors    2 RM (70
                                     \truck-day/ Iman-day
                      (Determined as in Part 4)


                      (Determined as in Part 5)


                                    D-5
                                                                      11,9807km'
                                                                      11,9457km*
                                                             5,712/kin
e. KIT \ / u adys )
0.53 gal fuel /
\W-dayJ
'200 hp\ /138 mach-day V/$0.428\
hp-day \ mach / \ ^z /\ gai J
u /I man-day\/$43.28 "\
- macn ^ mach
- . /I man-<
c. macn i mach
4 trucks /jg
km2
280 truck- days
y I man-day y
ia.y\ /$60.48 \
j 1 RM-day J
days) (' $4?-, ^
uajrJy \truck-dayy
/I man-day^ /$86.80 \
6, 2607 km2
877 km2
121 /km2
12, 8807 km2
24, 3047 km2
                                                                      12, 7037 km
                                                                         41 5/ km

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TABLE D.3.  Continued
7)  Temporary Storage
      *  Equipment   l_dpzer    (70 days)
          Crew
          Supplies
           (Fuel)
  km'
70 dozer-day   1 man-^day
   JZ2dozer-day
                     (Determined as in Part 4)
          Egui pment
           (Decon)     (Determined as in Part 5)
                                                $86.80
                                                man-day
                                                                        16,450/km*
                                                                        6,076/km*
                                                  5.08V km'
                                                                         104/km'
                                               TOTAL
                                                                    $137,000/km'
         TABLE D.4.   Machine-Days  and  Crews  Required  to  Clean  Up  1
                Equipment
      Harvesting-Chopping Machine
      (corn)
      Harvesting-Chopping Machine
      (hay, soybeans)
      Road Grader
      Small Front-End Loader
      Field Sod Machine
      Lawn Sod Machine
      Vacuumized Sweeper
      Firehosing
      Farm Tractor & Plow
                                      Machine-Days/km
                                              30
                                             70
                                            625
                                            138
                                            625
                                            . 21
                                            163
                                              8
                                      Crew Size
                                         3
                                         3
                                         3
                                         2
                                         1
                                         3
                                         1
     For costing the removal equipment and its crews (Table D.3, pt. 1 and
2), the cleanup time did not need to be known specifically.  However, time
is typically a factor in costs for support personnel, equipment decontamina-
tion, transportation to a temporary storage site, and temporary site require-
ments.  In-the case of field sod removal, two machines were assumed available
for removal, yielding a cleanup time of about 70 days/km2.
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     Support crew costs (Table D.3, pt. 3) were based on one foreman per
50 persons and one radiation monitor per 5 persons, as discussed earlier.
Supply costs for field sod removal (Table D*3,.pt. 4) included the cost
for diesel fuel.  Fuel requirements were based on the following equation:
                gal fuel \/   hp
                                                                        .(6)
            1.53
                 hp-day  /machine
                                                               /$/kn,2 \
     Machinery decontamination included the cost for cleanup of two machines
and is shown in Table D,3, pt. 5.
     For transportation of removed sod to a temporary storage site, four dump
trucks per km2 were considered available for hauling.  Cost factors for trans-
portation included equipment leasing, truck drivers, fuel supply, and equipment
decontamination.  Table D.3, pt. 6, shows the determination of these factors
for the field sod removal unit cost.
     Temporary storage site requirements involved the use of a bulldozer to
pile removed sod.  One bulldozer was considered .for, 1 km .  The same cost
factors were used here as for transportation; these are outlined in Table D.3,
pt. 7.
     By summing components 1-7 in Table D.3, the unburdened unit cost of
$137,000/knT for field sod removal was estimated.

REFERENCES                    .                    .."...              •
1.   Robert Snow Means Company, Inc., Building Construction Cost Data 1977.
     Duxburg, MA  02332,1977..                         >.  ... ,       ,
2.   L. E. Bruns, K. T. Key and B. A. Higley, Hanford Contaminated Sediment
     Stabilization Studies.  ARH-CD-640, Atlantic Richfield Hanford Company,
     Rich!and, WA, March 5, 1977.
3.   J. R. Young, Procedures for Estimating Nuclear Fuel Cycle Costs.  BNWL-2210,
     Battelle, Pacific Northwest Laboratories, Richland, WA  99352, 1977.
4.   Tri-Sjtate Motor Transit Company, Freight Tariff Number 1070-A.  Docket
     MC 109397, p. 5, effective July 26, 1977.
5,   Final Generic Environmental Statement_on Use of Recycle Plutonium 1n
     Mixed Oxide Fuel in Light Water Cooled Reactors.  U.S. Nuclear Regula-
     tory Commission, Vol. 4, p. XI-29, August 1976.
                                     D-7

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6.   H. L. Solberg, 0. C. Cramer and A. R. Spalding,  "Internal  Combustion
     Engines," Thermal Engineering.  John Wiley & Son,  Inc., pp. 189-305,  1960.
                                   D-8

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    APPENDIX E





ECOLOGICAL IMPACTS

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                                 APPENDIX E
                             ECOLOGICAL IMPACTS

     This appendix describes the ecological impacts that could be expected
from application of the EPA Guidance to the assumed analyses.  The application
of measures that could be taken to prevent more extensive .ecological damage
is also assumed.  Use of -these measures is made in the calculation of costs
for application of the Guidance.
     Descriptions of three reference sites and the assumptions for decontamina-
tion were presented in Appendices A and C, respectively.  In the three sub-
sections below, the ecological effects of decontamination activities are briefly
outlined for each site, according to the land types at the site and to alter-
native approaches to decontamination.
     Note that ecological damage from transuranic contamination would be
unlikely if no cleanup were undertaken.  In order to have radioecological
effects, it has been estimated that contamination would have to exceed
1
REFERENCE SITE ONE
     Land areas assumed to be decontaminated at this site included corn fields,
idle farmland, hay and soybean fields, pasture land, forest, residential area,
and commercial area.  The primary ecological effects would result from decon^
tamination of the croplands.
     The options for decontamination considered involved 1) removal of the top
2 in.  (5 cm) of soil, 2) plowing to a depth of 10 in. (25 cm), and 3) plowing
to a depth of 3 ft (1 m).  For croplands, the first option would result in
temporary minor effects, with only normal agronomic practices required before/
the land could be returned to use.  Plowing of the area is one normal practice,
therefore option 2 would result in no ecological effect.  Option 3, plowing to
                                      E-l

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 a  1-m depth, would  bring  some  subsoils  to  the  surface, which could increase
 the concentration of  salt or other plant toxins at rooting depths.  The lower
 permeability of many  subsoils  might make leaching of salt difficult and result
 in the need for additional soil treatment  to return the area to prime produc-
 tivity.  However, 1-m-depth plowing might  result in a lower availability of
 Plutonium because the contamination would  be buried below rooting depths.
      Overall, of all  options for decontamination of croplands discussed, plow-
 ing to a 25-cm depth  would have the least  effect and plowing to 1-m depth the
 greatest.  However, all effects would be temporary and easily mitigated by
 standard agronomic practices.  If possible, decontamination should be sched-
 uled  so that fields could be available  for planting in the spring.
      The effects of decontamination on  pasture lands would be similar to those
 on croplands.  Removal of the  top 5 cm  of  soil would require revegetation in
 the spring, following plowing  and seed  bed preparation.  Options 2 and 3 would
 have  results similar  to those  for cropland.  In general, effects on pasture
 land would be of little consequence for this site.
     Woodlot decontamination was assumed to require removal  of the littermat.
This would then have  to be replaced with mulch and fertilizer to restore the
 nutrient supply and mitigate potential erosion problems.
      Decontamination  of population areas would have primarily socioeconomic
rather than ecological effects.
      In general, ecological  effects associated with operations to clean up
all land types would  be minor and temporary.   Care would need to be exercised
in order that adjacent areas not be subject to excessive perturbation.

REFERENCE SITE TWO
     Decontamination of this reference site was assumed to involve forest  land,
shoreline,  and streams.   Decpntamination procedures were assumed to require
removal of the forest mat using small  front-end loaders and  manual  labor.   An
initial water stabilizer might be used on shorelines  prior to the application
                                     E-2

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of a  long-term stabilizer.  Soil removal was assumed  to be accomplished by use
of, a  road grader, manual labor, and a small front-end loader.  Streams were
considered to be monitored only.     -       -      .   ,             ;         :
      Ecological effects associated with the decontamination of forested areas
wuld be identical to those discussed for woodlots for Reference Site One.
However, the overall impact would be less because less land is involved in
this,  instance.                       ..          '    -     '•'
             -       '                         -v
      Decontamination of shorelines would impact aquatic life buried in the
sand  and perhaps birds nesting in the area.  However,  since the area is natu-
^ally disturbed by incoming tides, the impacts of decontamination would be of
limited significance.
      In general, all ecological effects would be of little consequence and
would not affect the areas of concern to any substantial degree.

REFERENCE SITE THREE                        .
      Decontamination of this reference site would entail cleanup of pasture
land, field crops, orchards, and irrigation ditches*
      Impacts from the removal of the top 2 in.  (5 cm)  of soil at this site
would be greater than those at the two sites above because soil types here
are sandier and not as rich in nutrients.  This condition would require addi-
tional soil  treatment beyond that employed for the other reference sites.
Revegetation should be initiated in the fall rather than the spring because
the fall is  the rainy season for this area.  The site would require revegeta-
tion with nonnative grasses because there is a low probability that the area
would recover to its original state and be productive  as pasture land.
     Plowing to 10-in.  (25-cm) and 3-ft (1-m) depths would result in impacts
similar to those at the Reference Site Two.  However9  revegetation would be
Inhibited since this area has less rainfall and poorer nutrient soil types.
Agricultural  land effects would be identical to those discussed for the
Reference Site Two.
                                      E-3

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     Ecological effects associated with orchards would result from the removal
of the top 2 in. (5,cm) of soil (plowing was not considered), which might
result in the loss of some trees.  Many .'orchard trees are extremely shallow-
rooted and could be seriously damaged by the machinery used.
                                       E-4

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REFERENCES                                                 <  -    - .:     A

 1.  F. W. Whicker,  Radioecology of Natural Systems.   Fifteenth Technical'*
     Progress Report to  ERDA,  EY-76-S-02-1156, pp.  42-43, 1977.^ ;;   •-.'  ••':•.-,•..

 2.  W. A* Rhoads, "A Wise  Resolution of the Pu-Contaminated  Lands5PYobleta
     in Certain Parts of NTS May Be to Isolate and  Maintain Them Without
     Further Disturbances:  A  Position Paper."   In:   Studies  of Environmental
     Plutonium and Other Transuranics in Desert  Ecosystems, NVO-153^Nevada
     Applied Ecology Group, U.S.  ERDA, Las Vegas, NV,  pp. 165-180, 1976.
                                      E-5
                                                       *US. GOVERNMENT PRINTING OFFICE: 1978  420-007/3716 1-3

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