UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
                       WASHINGTON, D.C. 20460


                           JUL 14  1994
                                                         OFFCEOF
                                                     PREVENTION. PESTICIDES AND
MEMORANDUM                                             TOXC SUBSTANCES

SUBJECT:  Guidance on Residential Lead-Based Paint,  Lead-
          Contaminated Dust,  and Lead-Contaminated Soil

FROM:     Lynn R. Goldman, M.D. IM/T^/^- (C- \JTX-bt.
          Assistant Administrator V

TO:     •  See Below


     Recently, the Agency has received  an increasing number of
requests for advice on residential  lead-based paint hazards
which, by statutory definition, includes  hazards from lead-
contaminated dust and soil in and around  homes.   These requests
have come from State and EPA  Regional officials,  as well as
public health and housing personnel.  While the  Agency is in the
process of developing a rule  to address these hazards under
Section 403 of the Toxic Substances Control Act  (TSCA), 15 USC
S2683, we believe that it is  prudent to respond  to these requests
by issuing guidance at this time based  upon our  best currently
available information.

     The attached recommendations will  serve as  guidance until
the promulgation of the section 403 rule.   Depending upon the
results of ongoing studies, we may  revise the numerical values,
particularly for dust, in additional guidance prior to the
section 403 rulemaking.
Addressees:
     Director, Air Management  Division,  Region 1
     Director, Environmental Services  Division,  Region 2
     Director, Air, Toxics, and  Radiation Management Division,
          Region 3
     Director, Air, Pesticides,  and  Toxics Management Division,
          Region 4
     Director, Environmental Sciences  Division,  Region 5
     Director, Air, Pesticides,  and  Toxics Division, Region 6
     Director, Air and Toxics  Division,  Regions 7, 8, 9, 10

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cc:  Chier, Pesticides and Toxics Substances Branch,
          Regions 1, 2, 4, 5, 10
     Chief, Toxics and Pesticides Branch, Regions 3 and 7
     Chief, Pesticides and Toxics Branch, Regions 6 and 9
     Chief, Toxic. Substances Branch, Region 8
     Regional Lead Contacts, Regions 1-10
     Joe Carra
     Bill Hansen
     John Melone
     Lin Moos
     Ooreen Cantor
     Brion Cook
     Dave Topping
     Section 403 Workgroup

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         AGENCY GUIDANCE ON RESIDENTIAL LEAD-BASED PAINT,
        LEAD-CONTAMINATED  DUST, AND LEAD-CONTAMINATED  SOIL

                                                  July 14,  1994

     Recently EPA has received an increasing number of requests
for advice on residential lead-based paint hazards,  including
hazards from lead-contaminated dust and soil in and around homes.
These requests have come from State and EPA Regional officials,
as well as from public health and housing personnel, concerned
with childhood lead poisoning.  While the Agency is in the
process of developing a rule to identify these hazards under
section 403 of the Toxic Substances Control Act (TSCA),  15 USC
2683, we believe it is appropriate to respond to these requests
by issuing guidance at this time based upon our best currently
available .information.


     EPA believes that it would not be prudent to issue national
regulatory standards under section 403 at this time since a
number of relevant research activities are currently underway and
are scheduled to be completed in the near future.   It is expected
that this research will allow the Agency to develop standards
that would more accurately direct resources toward residences
that would benefit most from abatement and control activities.
In the interim,  the recommendations in this document represent
the Agency's  best judgement given its current state of knowledge
and experience and are intended to serve as guidance until the
promulgation  of the TSCA section 403 rule.  EPA emphasizes that
these recommendations are intended solely as guidance and,  as
such, are not intended, nor can they be relied upon, to create
any obligation or right that may be created in the future by
rules issued under TSCA section 403.   Persons to whom this
guidance is directed may decide to follow it or to act at
variance with it and may use the guidance in conjunction with
analysis of specific site circumstances.   The Agency also
reserves the  right to change this guidance at any time without
public notice.


Use of This Guidance
     It is the Agency's intent that this guidance be used to
prioritize primary prevention activities that address hazards
from lead in and around residences.  EPA expects that these
hazards will be among those that will be identified when
regulations are issued under TSCA section 403.  The levels and
conditions described  in this guidance should be used  by
decisionmakers  (risk  assessors, risk managers, etc.)  to identify
lead-based paint hazards, sources of lead exposure, and the need
for control actions in residential environments where children
may be present.  They should not be regarded as definitive
statements of the lead hazard associated with  specific
environmental lead measurements, but the Agency believes that  the

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criteria provided herein can inform and guide decisions on the
identification of lead-based paint hazards and appropriate
responses.  Also, any  lead-based paint-related activities
(including lead detection, abatement, clearance,  and disposal)
should comply with all Federal, State, and local  regulations.

     Additionally, it  should not be inferred that the
recommendations in this guidance will, in and of  themselves,
guarantee the elimination of risks to children from residential
lead exposure.  Rather, this guidance is an attempt to identify
the general types of environmental conditions and response
activities that, given the current state of our knowledge, are
likely to reduce risks over various broad ranges  of environmental
lead levels that may be found in the residential  environment.

     Finally, this guidance is not to be applied in addressing
potential threats from lead at CERCLA and RCRA Corrective Action
sites.  Guidance developed by the Office of Solid Waste and
Emergency Response is  the appropriate tool for addressing these
types of sites.


General
     Although considerable progress has been made in the
reduction of environmental lead (e.g., the phase-out of leaded
gasoline and lead-soldered food cans, more stringent drinking-
water standards, etc.), residual lead contamination remains
ubiquitous in both residential and commercial areas.  In this
guidance, the Agency's approach is to focus on the s'urces of
lead that are related  to the nation's housing stock.  While there
are numerous pathways  for lead exposure, eliminating or reducing
the role of^ lead-based paint and lead-contaminated soil as direct
exposure sources  (and  as contributors to indoor lead dust) will
significantly reduce total lead exposures from residential
sources.

     Soil and dust at  other locations  (e.g., day care centers,
public playgrounds, and other non-residential areas) can also be
important contributors to a child's lead exposure.  While these
areas are outside the  scope of TSCA section 403 authority, their
potential contribution to a child's total lead exposure should
also be considered when deciding upon community-wide responses to
environmental  lead.

      In addition, the  Agency recognizes that a number of  factors
contribute to  risks  from  lead, including the nature of the lead
sources, the amount  of exposure to each source, and others.   In
this  guidance,  the Agency is using the  levels of lead  (and, for
soil, the expected extent  of children's contact) as a surrogate
for risk.

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     At low to moderate levels of lead in soil and dust, and
where paint deterioration is not extensive nor substrate failures
or moisture problems present, EPA believes that interim
controls1   can be an effective way to temporarily  reduce
exposures.  Interim control of lead in dust,  soil, or painted
surfaces r.ust be predicated upon demonstrated ability to maintain
and monitor such management strategies, based upon condition of
the environment, expected use and contact, and reasonably
anticipated changes in condition and/or use.   At higher lead
levels in soil and dust, and under deteriorated conditions of
lead-based painted surfaces, more rigorous and long-term exposure
reduction interventions should be taken.  Under certain
conditions related to extremely high soil concentrations or
structural damage to painted surfaces, interim controls may not
be appropriate for particular areas or components and only
complete abatement of the component by an adequately trained
professional will ensure adequate protection.

     EPA policymakers do not believe that they are in a position
to identify these levels and conditions as regulatory standards
at this time.   However, the Agency has developed this guidance
based on consideration of estimated health impacts from lead
exposure,  the need to prioritize residences that would benefi
from abatement, and comparison of risk reduction benefits ana
cost allocation projected for various control measures.


Sequence of Source Control Activities
     Because of the interrelationship between lead-based paint,
lead-contaminated dust, and lead-contaminated soil (e.g., lee. i in
paint can contribute lead to dust and soil, lead in soil can
contribute lead to interior dust, etc.), it is important that the
sources of lead be considered in proper order when conducting
response activities.  For example, if soil is being contaminated
by deteriorating exterior lead-based paint,.it is preferable to
address the paint first, immediately followed by the soil.  If
the soil were addressed first, .it may become  recontaminated
during work o.i the paint.  In general, exterior paint should be
addressed prior to soil, while soil and interior paint should be
addressed prior to interior dust.  This best avoids potential
recontamination problems among the three.  Exceptions should be
made when there will be delays in addressing a source or when
levels in one medium  (such as interior dust)  are clearly
hazardous and immediate actions are needed to protect health.
If, in the previous example, the exterior paint could not be
     1"Int.3rim controls" means a set of measures designed to
reduce temporarily human exposure or likely exposure to  lead-
based paint hazards, such as paint  repair, specialized cleaning,
temporary containment and ongoing monitoring of lead-based paint
hazards or potential hazards.

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addressed immediately for some reason, it would not be
appropriate to delay attention to the soil, since the soil could
continue to act as a source of exposure.


Lead-Based Paint
     Lead-based paint is of concern both as a source of direct
exposure through ingestion of paint chips,  and as a contributor
to lead in interior dust and exterior soil.  Lead was widely used
as a major ingredient in most interior and exterior oil-based
paints prior to 1950.  Lead compounds continued to be used as
corrosion inhibitors, pigments, and drying agents from the early
1950's.  In 1972, the Consumer Products Safety Commission limited
lead content in new residential paint to 0.5% (5000 ppm) and, in
1978, to 0.06% (600 ppm).

     The Department of Housing and Urban Development  (HUD)
estimates that three-quarters of pre-1980 housing contain some
lead-based paint.  The occurrence, extent and concentration of
lead-based paint increase with the age of the housing.  90% of
privately-owned housing units built before 1940 contain some
lead-based paint; 80% of 1940-1959 units; and 62% of 1960-1979
units.2

     Coatings of residential paint are defined by statute to be
lead-based if the lead content exceeds either 1.0 mg/cm2 or 0.5%
by weight.  Lead-based paint should be either abated or addressed
through interim ^ntrols if it :.s found in any of the following
circumstances:   (1) it is deteriorated  (in any location);  (2) it
is present  (in any condition) on impact or friction surfaces; or
(3) it is present  (in any condition) on surfaces that are
accessible for mouthing or chewing by children.  "Deteriorated
paint" means any interior or exterior paint that is peeling,
chipping, chalking, or cracking, or is located on an  interior or
exterior surface or fixture that is damaged or deteriorated.  An
"impact surface" is an interior or exterior surface that  is
subject to damage from repeated impacts  (e.g., certain parts of
door frames).  A "friction surface" is an  interior or exterior
surface that is subject to abrasion or friction  (e.g., certain
window, floor, and stair surfaces).  A surface is considered to
be accessible  for mouthing or  chewing by children if  it protrudes
from the surrounding area to the extent that  a child  can  chew the
surface, and is within three feet  of  the floor or ground  (e.g.,
window sills,  railings,  and  the edges of stair treads).
 (Recommendations for sampling  of painted surfaces are attached.)
      Comprehensible and Workable Plan for .the Abatement of Lead-
Based Paint in Privately-Owned Housing:   A Report  to Congress,
U.S.  Department of Housing and Urban Development,  Washington,  DC,
December 7, 1990.

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     When it is determined that paint abatement3  and/or  interim
control activities will be performed on housing components,  they
should be performed according to practices that will be described
in the 1995 HUD Guidelines4  and the  regulations to be
promulgated under section 402 of TSCA,  15 USC 2682   (as
appropriate for the unit in question),  including clearance
testing.  The section 402 standards are expected to be proposed
in several months.  (Guidance on sampling and analysis of dust
for clearance testing is attached.)   Until either the HUD
Guidelines are published in final form or the section 402
standards are issued,  abatement activities should be performed
according to the current HUD guidelines and interim control
activities should be conducted according to state and local
requirements, since they are not addressed in the existing HUD
guidelines.


Lead-Contaminated Dust
     In many cases, lead-contaminated interior dust can be the
most direct source of a child's lead exposure, acting as a
pathway for lead from lead-based paint, exterior soil, dust
carried home from occupational exposure, etc.  This guidance
primarily confronts this source by addressing the residence-
related sources of lead in dust--namely, lead-based paint and
soil.  The effect of the recommendations for paint and soil is
removal or control of these two sources, followed by cleanup of
the previously contaminated dust.

     In the context of their lead abatement programs, HUD hap,
established "clearance levels," which are part of the evaluation
     3"Abateroent"  means any set of measures designed to
permanently eliminate lead-based paint hazards, including the
removal of lead-based paint and lead-contaminated dust, the
permanent containment or encapsulation of  lead-based paint, the
replacement of lead-painted surfaces or fixtures, and the removal
or permanent covering of lead-contaminated soil.

     4HUD is developing detailed technical guidelines pursuant to
section 1017 of Title X of the Housing and Community Development
Act of 1992 to describe best practices for all activities related
to the evaluation and control  of  lead-based paint hazards.  While
applicable specifically to federally-assisted  housing,  the
described practices provide useful technical guidance  for all
types of housing with  similar  conditions.  These Guidelines are
now undergoing clearance and approval within HUD and are
available in draft form for review.  These Guidelines  will
supersede HUD's 1990  "Interim  Guidelines  for Hazard
Identification and Abatement in Public and Indian Housing," which
focused primarily on  testing and  abatement (and  do  not  address
risk assessment or interim controls).

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of the thoroughness of abatement and subsequent cleanup
activities.  Clearance levels are "technology based"--that is,
they indicate what can be achieved after proper abatement or
interim control actions.  Clearance levels are appropriate since
the marginal cost of attaining them is typically quite low once
an intervention is underway, and EPA and HUD experience indicates
that they can be achieved through proper abatement and interim
control activities.  The Agency therefore recommends that the
following clearance levels be met after abatement or interim
control activities have been performed:


          Location                 Lead Loading

     Uncarpeted Floors5       100 ng/ft*  (0.93  mg/m2)

     Interior Window Sills    500 M9/ft2  (4.65  mg/m2)

     Window Wells             800 M9/ft2  (7.45  mg/m2)


     Section 403 directs the Agency to issue rules that identify
lead-based paint hazards, which include lead-contaminated drs'>:
that would result in adverse health effects.  The levels that
will be developed in the section 403 rulemaking will indicate to
risk assessors that a lead-based paint hazard (for dust) exists.
Obviously, the levels will be different in purpose than clearance
levels--the former indicating that a hazard is present and the
latter indicating that source control and cleanup have been
appropriately performed.  Accordingly, hazard levels are to be
used during risk assessment and re-evaluation, whereas clearance
levels are used to confirm the success of abatement and/or
interim control activities.

     Until the standards can be developed under section 403 the
above-listed clearance levels should be used in identifying lead-
based paint hazards and sources of lead exposure, and determining
the need for control actions.  The Agency reiterates that these
recommendations are based upon lead levels that have been
demonstrated to be achievable through abatement and interim
control activities and they are not based upon projected health
effects associated with specific dust lead levels.  As a result
of continued Agency evaluation of the relationship between
interior dust  lead levels and health effects, these hazard levels
      5It is anticipated that the 1995 revision to the HUD
guidelines will lower the current  clearance standard of  200
/zg/ft2 for uncarpeted floors to 100 jig/ft2.

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may be revised in future guidance.6  Also, when  assessing
multiple sources of lead,  dust lead concentration may be a more
appropriate measurement.  The utility of concentration
measurements for identifying section 403 hazards from dust will
be further considered in the development of  the section 403
rulemaking.

     Other potential sources of lead that may be present in house
dust in addition to lead-based paint and lead-contaminated soil
include neighborhood sources, such as demolition of a nearby
building,  sandblasting of a bridge,  or other activities involving
structures that may contain lead-based paint.  Also,  lead may be
brought into the home on clothing of residents employed in lead-
related occupations, or as the result of some hobbies.
Additionally, deteriorated paint which contains some lead, but at
levels lower than 1.0 mg/cm2  or 0.5% by weight,  could be a
source.  Depending upon the extent to which these sources
contribute lead to interior dust, regular cleaning of the
residence may not provide sufficient reduction in the level of
lead exposure from dust, and the sources should be identified and
controlled.   It is often possible to identify these situations
through sampling and analysis of the interior dust.

     Since lead levels measured by wipe samples  ("dust  lead
loading")  are dependent upon both the amount of collectable dust
on a surface and the concentration of lead in that dust, high
values for either of these two factors could produce high wipe
sample lead results.  That is, a large amount of low-lead-
concentration dust and a small amount of high-lead-concentration
dust could result in sir Liar wipe sample results.  Therefore,
while low dust lead loading values may indicate that sources that
contribute to household dust have been sufficiently controlled,
high values ^could result from any of the following situations:
(1) there are some insufficiently controlled sources that
continue to contribute significant amounts of lead to the dust;
(2) relatively large amounts of low-lead dust are present; or  (3)
some combination of these occurs.

     Dust lead concentration measurements can provide insight  as
to which of these conditions is resulting in high wipe  sample
values, as well as assist risk assessors in  identifying possible
sources.  For example,  if interior paint has been ruled out  as  a
source, and dust concentrations approach those  of exterior soil,
     'Principal among the studies expected to provide further
information on the relationship between dust  lead and children's
blood leaH levels is the recent Rochester Lead-in-Dust  study.
This HUD-funded study was conducted by the University of
Rochester from May to December of 1993 and included  approximately
200 children whose primary source of lead exposure was  from house
dus'c.  Peer review of this study began in June of 1994.

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it may well be  the  result of soil being tracked into the house
from outside.   Also,  if paint is in sound condition and soil
concentrations  are  low but the interior dust concentrations are
high, it is possible  that other sources, such as dust carried
home from lead-related work, are present.  Through a systematic
process of elimination, many of the sources of lead in house dust
can often be determined.  While a detailed discussion on how to
perform these types of assessments is outside the scope of this
guidance, these  issues will be addressed by certification
procedures and  training requirements for parties involved in  .
lead-based-paint activities  (which includes abatement, inspection
and risk assessment)  currently being developed under section 402
of TSCA.

     To ensure  that excessive exposures are not being caused by
the amount of dust  in the house, the Agency recommends that
efforts always be made to minimize dust in residences, even after
paint and dust  sources have been addressed through any needed
interim control  and/or abatement activities.  A key component of
these efforts is the  need to maintain a residence in a cleanable
state (i.e., in  such  a condition that it can be effectively
cleaned by the occupant using reasonable cleaning procedures).
For example, water-damaged or worn wood flooring may have a rough
surface with crevices from which dust cannot be readily removed
through routine  wet mopping.  Such surfaces should either be
replaced or repaired  so that they are cleanable.  Likewise, it is
important that  the  residence be effectively and regularly cleaned
and that exposures  to anv interior dust be minimized.
Recommended activities to reduce Interior dust lead levels and
associated exposures  include:  mopping floors, window ledges, and
accessible surfaces with a warm detergent solution; washing
pacifiers and bottles if they fall on the floor; washing toys and
stuffed animals  regularly; and ensuring that children wash their
hands before meals, naps, and bedtime.  These activities, as well
as the importance of  nutrition and other factors relevant to
children's risk  from  lead exposure, should always be stressed as
part of public  education and awareness programs, regardless of
the measured lead concentration in any one medium.


Lead-Contaminated Soil
     Lead-contaminated exterior bare soil is of concern both as a
direct source of exposure through inadvertent ingestion due to
children's normal hand-to-mouth activity, and as a contributor to
indoor dust lead levels  (e.g., when tracked into a residence from
outside).

     Common sources of lead  in residential soil include
deteriorating exterior lead-based paint and historical airborne
deposition onto the soil  surface as the result of point  source
emissions ov leaded gasoline.  These sources have added
substantially to the  naturally occurring lead in soils,  which

                                B

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generally range from b - 50 parts per million7.  Also,
industrial sources such as smelters,  recycling facilities,  and
mining activities can result in lead contamination at residential
areas.  This adds difficulty in relating lead levels in soil to
potential health effects because lead from different sources may
pose different levels of potential hazard.  One apparent
difference is the extent to which ingested lead originating from
different sources is taken up into the body--that  is, the
bioavailability of the lead.  Decisionmakers should consider this
and any other available information when implementing the
recommendations contained in this guidance,  particularly where
non-paint sources of lead are involved.  That is,  if the soil is
contaminated by lead from other sources, rather than lead-based
paint, decisionmakers should investigate the types of lead
compounds present and their unique characteristics.  Agency
guidance on consideration of bioavailability of lead in risk
assessment can be found in the Guidance Manual for the Integrated
Exposure Uptake Biokinetic Model for Lead in Children (available
from National Technical Information Service, U.S.  Dept.  of
Commerce, Attn-. Sales, Springfield,  VA  22169 (703/487-4650), as
document number PB 93-963510).

     S'il lead concentrations in the Unit:d States vary widely,
from less than one to tens of thousands of parts per million
(ppm).  This range of concentrations and attendant potential
exposure levels indicates that it is appropriate to develop a
scaled strategy of risk reduction activities, depending upon the
concentrations at particular locations and other site-specific
factorr.  The Agency's recommendations for response acti 'ties at
varying soil lead concentrations are as follows.

     The Agency is recommending that  (depending upon use
patterns, populations at risk, and other factors), when lead
concentrations are observed that exceed 400 ppm in bare soil,
further evaluation should be undertaken and physical exposure-
reduction activities, commensurate with the expected degree of
risk, are appropriate.8  The Agency  believes that  the 400 ppm
     7U.S.  Environmental Protection Agency (1989)  Review of the
National Ambient Air Quality Standards for Lead:  Exposure
Analysis Methodology and Validation.  U.S. EPA Office of Air
Quality Planning and Standards, RTP, NC. EPA-450/2-89/011.

     8The selection of 400 ppm in this guidance is based upon two
decisions.  The first is that the  level should help in  reducing
the threat that environmental lead poses to the public.   In this
guidance, EPA estimates that beginning exposure reduction
activity at 400 ppm will help ensure that a typical child  or
group of children  exposed to lead  would have an estimated  risk of
no more than 5% of exceeding a blood lead level of 10 ^g/dl.
This benchmark may change in the future section 403 rulemaking.

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     The second decision is to use the best available tool for
assessing the relationship between children's blood lead levels
and environmental lead levels.  Current research indicates that
young children are particularly sensitive to the effects of lead
and require specific attention in the development of lead
standards.  A level that is protective for young children is
expected to be protective for older population subgroups.  In the
same environmental setting, pregnant women would be expected to
have blood lead levels lower than would young children,  and this
may further limit fetal exposures.

     The Agency has examined both epidemiological studies and
modeling approaches for this purpose.  Both of these will be
further evaluated as part of the effort to develop section 403
rulemaking.  However, given the need to issue guidance at this
time, the Agency is choosing to base the guidance on the
Integrated Exposure Uptake Biokinetic  (IEUBK) model, which EPA
designed to evaluate exposures to children in a residential
setting.

     In general  the model generates a probability distribution
of blood lead levels for a typical child, or group of children,
exposed to a particular soil lead concentration and concurrent
lead levels from other sources.  The spread of the distribution
reflects the observed variability of blood lead levels in several
communities.  This variability arises from several sources,
including behavioral and cultural factors.

     The identification of lead levels from other sources  (due to
air, water, diet, etc.) is an essential part of characterizing
the appropriate blood lead distribution for a specific
neighborhood or site.  For the purpose of deriving the 400 ppm
value used in this guidance, the background lead exposure inputs
to the  IEUBK model were determined using national averages, where
suitable, or typical values.  Thus, the estimated level of 400
ppm is  associated with an expected "typical" response to these
exposures, and should not be taken to  indicate that a certain
level of risk  (e.g., exactly 5% of children exceeding 10 jig/dl
blood lead) will be observed in a specific community  (e.g., in a
blood lead survey).

     Because a child's exposure to lead  involves a  complex array
of variables, because there is population  sampling  variability,
and because there  is variability  in environmental  lead
measurements and background levels of  lead in food  and drinking
water,  results from  the model  may differ  from results of blood
lead screening of  children  in  a community.   Extensive field
evaluation of  the  model  is  in  progress and- the model will  be
evaluated  further  once  these  efforts  are  completed.  EPA may  base
the  future  section 403  rulemaking on  the  model once these

                                10

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level serves as a reasonable current benchmark for the purposes
of this guidance.  Therefore,  the Agency recommends that further
evaluation and appropriate exposure-reduction activities be
undertaken when soil lead concentrations exceed 400 ppm at areas
expected or intended to be used by children.9   (Recommendations
for soil sampling and analysis are attached.)   Further evaluation
activities may include blood lead screening of children and
others in the community.

     When soil lead levels exceed 400 ppm and children are likely
to be present, exposure-reduction responses should focus on
interim controls designed to change use patterns and create
barriers between children and contaminated soil.  This involves
taking steps to keep children away from certain areas and to
reduce exposure to bare soil in accessible areas.  As an example
of changing the use pattern, thorny shrubs can be planted to keep
children from playing around houses that have elevated soil lead
concentrations immediately next to the house.   Also, play
equipment can be moved from bare soil contaminated areas to
encourage children to play elsewhere or, for more highly
contaminated areas, access can be restricted by fencing.  As an
example of the use of barriers to reduce exposure, grass or other
groundcover can be estab'ished and maintained or the area can be
covered with mulch or gravel.   While the effectiveness of many of
these interim control actions cannot yet be quantified, the
Agency believes that they can reduce exposure.  However, whenever
interim controls are used, their condition should be monitored to
ensure continued effectiveness.  For example,  the condition of
plants, groundcover, .stc., that serve as use-modifying and
barrier-type elements sh 
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of this  range  (e.g.,  between  400 ppm  and  2000 ppm), emphasis
should be placed on reducing  exposures  through  interim controls
at those areas  expected or intended to  be used  by children.  If
the area is  not frequented by children, these exposure reduction
activities may  be less  rigorous.  Where bare-soil lead levels are
found to be  2000 parts  per million or more, interim controls
should be implemented even if the area  is not frequented by
children.

     Increasingly aggressive  exposure-reduction activities are
warranted at higher soil  lead levels, with very high levels
indicating that soil  abatement may be necessary.  For purposes of
prioritizing abatements,  the  Agency recommends  soil abatement
when lead levels are  found at 5000 parts per million or more in
residential bare soil.  Appropriate activities  at this level of
lead concentration may  include removal  and replacement of the
soil, the use of more permanent covers  (e.g., paving), or other
activities.  Of course, state and local agencies should consider
any other factors that  affect the actual risks  and benefits of
abatement when  determining whether abatements may be necessary at
lower levels, including,  for  example, prevalence of elevated
blood lead levels in  children.

     The Agency is suggesting BOf., ppm  for this higher level
because of the  need to  prioritize the types of activities that
can often be resource intensive.  Factors considered in the
choice of this  level  include  the risk reduction that may be
achieved by different measures and the  resources needed to reduce
those risks.  Consequently, this level  is designed to indicate
where there is  a relatively highe" certainty that abatement or
other extreme activities  would be appropriate from a risk
reduction and resource  prioritization perspective.  Based upon
estimates of residential  soil lead distributions  (from HUD,
1990) ,  5000 'ppm would target  the soil at an estimated 1/2% of
U.S.  homes.

     Because of the likelihood that lead-contaminated soil will
have previously contributed lead to interior dust, specialized
cleaning is recommended for the interior of residences to meet
dust clearance  levels after soil abatement or interim control
activities have been  conducted.

     The Agency's recommendations for residential lead-
contaminated soil are summarized in Table I.
                                12

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                        Table I--EPA Recommendations for Response Activities for Residential Lead-Contaminated Bare Soil
           Area of Concern
   Dare Soil Lead
Concentration (ppm)
                       Recommended Response Activities
Areas expected to be used by children,
including:
   »  residential backyards.
   »  daycare and school yards,
   »  playgrounds,
   »  public parks, and
   *  other areas where children gather.
    400-5000
Interim controls to change use patterns and establish harriers between children and
contaminated soil,  including:
   »  planting ground cover or shrubbery to reduce exposure to bare soil,
   *  moving play equipment away from contaminated bare soil.
   *•  restricting access through posting, fencing, or other actions, and   /
   »  control further contamination of area.
Monitor condition of interim controls.
Public notice of contaminated common areas by local agency.
                                              > 5000
                      A jatement of soil, including:
                         » removal and replacement of contaminated soil, and
                         :- permanent barriers.
                      Public notice of contaminated common areas by local agency.
                                            2000-5000
Areas where contact by children is less
likely or infrequent
                                              > 5000
                      Interim controls to change use patterns and establish barriers between children and
                      contaminated soil, including:
                         » planting ground cover or shrubbery to reduce exposure to bare soil,
                         * moving play equipment away from contaminated bare soil,
                         » restricting access through posting, fencing, or other actions, am.
                         * control further contamination of area.
                      Monitor conditk...  f interim controls.
                      Public notice of contaminated common areas by local agency.
                      Abatement of soil, including:
                         »  removal and replacement of contaminated soil, and
                         »  permanent barriers.
                      Public notice of contaminated common areas by local agency.
                                                                     13

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Relationship of Soil Levels in This Guidance to the OSWER Interim
Soil Lead Directive.
     A variety of Agency programs address lead under a number of
statutes.  Lead in soil is addressed under TSCA Title IV
(including TSCA sections 402 and 403), the RCRA Corrective Action
program, and CERCLA  (Superfund), ea_h of which differs somewhat
in purpose and in the types of sites to which they apply.  Title
IV section 403 regulations, which have yet to be issued, will
identify lead hazards in paint and residential dust and soil.
RCRA Corrective Action applies to RCRA hazardous waste sites.
CERCLA applies to sites that have been contaminated by releases
of CERCLA hazardous substances  (which include lead).

     While this guidance applies to housing, which is a
significant part of the coverage of TSCA Title,IV, it is not
issued under the legal standards of any of these statutes, nor is
it to be used to support statutorily driven requirements of
CERCLA or RCRA.  Instead, the guidance is designed to allow
screening of the worst sources of lead-contaminated soil related
to the housing stock among the potentially huge number of sites
affected.  The top one percent of housing sites consists of about
1,000,000 locations.

     Because there is such a large number of housirj sites, the
purpose of this guidance is to recommend a set of nationwide
levels that will screen those sites at which, EPA expects,
decisionmakers will want to consider various risk reduction
activities.  The higher the level and the more likely exposure
w-11 occur, the more aggressive the risk reduction activ.  ies
undertaken should be.  The ultimate decision, howev .r, will be
made locally by various federal, state and local officials, or by
building owners, operators or occupants.  These decisionmakers
will need to consider a variety of issues, including the risk
reduction to be achieved by different measures and the  resources
needed to reduce those risks.  Given  the wide applicability of
this guidance, EPA has developed generic standards to deal with
the most risky sites--in particular,  those where the Agency  feels
most confident that  actual adverse effects could occur.

     The Agency's recommendations  for evaluating RCRA Corrective
Action  and CERCLA sites  are contained in the OSWER Interim Soil
Lead Directive.  The OSWER directive  deals with a  much  smaller
number  of  sites, at  which  extensive site characterization  will
have been  performed  before cleanup decisions are made.   RCRA and
CERCLA  programs, thus, will often  have  site-specific  exposure
values,  which  may be in  a  relatively  narrow range.  As  a result,
values  chosen  for action under the RCRA or  CERCLA programs may be
different  from those selected under this guidance.  Also,  once
the section  403  regulations  are promulgated, OSWER intends to
issue a final  (to replace  the interim)  directive.
                                 14

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The Section 403 Rulemakii.Q
     At present,  the Agency's section 403 rulemaking activities
are focused on a variety of technical issues related to more
accurate assessment of the risks associated with residential
lead-based paint, lead-contaminated dust, and lead-contaminated
soil.  These activities include continued analysis of models and
slope studies, including evaluation of the range of environmental
conditions over which they are adequate.  Complicating factors
include likely differences in the bioavailability of lead from
different sources and the variability in dust lead levels on
interior surfaces.  Because the Agency's work on these issues
involves ongoing as well as previously published research,
additional time will be required before levels for lead-based
paint hazards can be determined with more specificity and
proposed in the section 403 rulemaking.

     As a result of these additional investigations, the section
403 rulemaking may differ from this guidance in a number of
areas.  These may include the role of dust concentration  (in
addition to, or in place of, dust lead loading), the quantitative
or relative degree of blood lead level reduction that may be
targeted, methods to relate environmental lead measurements to
expected r^ood lead levels, and holistic standards rather th~n
specific Bevels for each exposure source.
Attachments

     Guidance  for Measuring Lead  in Soil and Paint

     Sampling  and Analysis of Dust for  Clearance Testing
                                15

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            GUIDANCE FOR MEASURING  LEAD IN SOIL AND PAINT
                                                                           July 1994
PREFACE

       Lead-contaminated house dust is considered  the  most  significant source  of lead
poisoning for the greatest number of children.  All house dust contains some lead; the amount
depends on lead contamination  from other sources such as deteriorated  lead-based paint and
lead-contaminated soil.  Millions of children live in dwellings with high dust-lead levels and
routinely put dust-laden  fingers,  toys, and other objects into their mouths.  Deteriorated  lead-
based paint and soil also may individually contribute  significantly to a child's lead exposure
if ingested.  However, a more common scenario is the contamination  of house  dust by  paint
and soil and the child's subsequent ingestion  of the contaminated house dust.   One way to
control high house dust lead levels and dust-lead exposure is to control the sources of lead that
contaminate house dust,  namely lead-contaminated bare soil and deteriorated lead-based paint.

SOIL SAMPLING  OVERVIEW

       Soil is a major reservoir of lead in our environment. It has been contaminated with lead
from  many years  of airborne paniculate fallout  from automobile  exhaust, from industrial
sources,  and from  the extensive use  of lead-based  paint  on residential housing anJ  other
structures.  Children who play in bare  soil may be directly exposed to lead.  Soil tracked into
the home (e.g.,  on shoes or by wind) contaminates house dust and, thus, may expose children
through the dust medium.  The purpose of this section is to assist the reader to develop and
implement a soil sampling strategy to  determine  whether the soil outside of a dwelling poses
a significant health hazard to children.

       Because  only areas of bare soil are considered likely lead hazards,' the focus of this
guidance  is to assess  lead  levels in areas of bare soil.  While  only bare soil needs to be
sampled, a property  owner may  wish to have additional sites sampled  if the ground covering
on those sites may be  disturbed by such activities  as gardening or excavation.

A soil sampling strategy should  be designed to:

       •      Identify the location of soil-lead hazards outside of the dwelling.

       •      Provide recommendations to the property owners or other interested parties on
              the best ways to control identified hazards.

       •      Do the assessment at an affordable price to enable  most property  owners  in the
              United States to have such an assessment  conducted.

       Due to the diversity of housing stock in the U.S., residential soil-lead assessments must
        Title X defines 'Lead contaminated toil* as b*re toil on residential property that contains lead at or in excess of the levels
determined by the EPA to be hazardous to human health.

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be done case by case.  The federal government can provide only general guidelines on where
to collect samples.  Actual sampling  locations are based on information obtained  during  a
preliminary assessment  of the property and  on the professional judgment of  the  person
collecting the samples.

       If sample analysis costs were trivial, then numerous soil samples could be collected at
each residence to  fully  characterize lead levels.  But analytical cost,  in the range of $15 per
sample, is not trivial. Therefore, to keep costs affordable, the sampling strategy must limit the
number of soil samples analyzed.

       When collecting only a limited number of samples from a yard, the major source of
uncertainty in the results is from collecting samples from very small areas relative to the total
area of interest.  Imagine that a  single soil sample  is collected from an unusually high, but
small,  lead-cpntaminated area, or  from a small section of the yard that recerMy  had  lead-free
potting soil spilled on it.  Most of these variations are out of the control of or unknown to the
person collecting samples.  One simple approach to reduce this problem is to sample  from
larger  areas.

       The easiest and most cost-effective way to sample from larger areas is to collect field
composite samples.  A field composite sample consists of individual sub-samples collected
from two or more locations and combined into one sample for analysis (the composite sample).
When  only  a few samples  can be feasibly analyzed at a residence due to time and  money
constraints,  composite  sampling  offers a more  cost-effective approach  and provides  more
accurate information than collect;ng a few single location samples.

       At least two composite samples per dwelling or building should be collected where bare
soil is present. General sampling locations are as follows:

       •      one from bare soil  in the child's principal play area(s)  and

       •      one from bare soil  areas in the front or back yard (if present) and/or from the
              foundation drip line.

Vegetable  gardens,  pet sleeping  areas, and bare pathways are also potential sampling  sites.
depending on the  situation.

       Once sampling areas are identified,  sub-sampling locations within these areas  need  to
be determined. No  more than ten sub-samples should be collected into  one composite  sample
in composite  samples may  add extra costs to laboratory lead analysis.

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Determining Collection Locations  for Each Comoosite

       Option  A
             Sub-sampling locations in bare soil play areas are selected by first sketching the
       area and then  drawing a circle just encompassing  the accessible  bare area. A second
       circle is drawn inside  the  first with  one-half the radius and  three equally-spaced
       sampling locations selected  at random on the inner circle.  Soil  sub-samples  are  then
       collected at each location. This process may be repeated for up to three bare soil  play
       areas, if present.

             To sample the building foundation or dripline, take four individual sub-samples.
       Where possible, given accessibility limitations and the availability  of bare soil,  each
       sub-sample should be located at random in a bare soil area at the dripline on a different
       side of the house.  Composite the four individual foundation/dripline sub-samples into
       one sample for lead analysis. At other sampling locations  in the yard, samples should
       be collected following the procedures for play areas.

       Option  B
             Each composite  sample should  consist of bare  area soil  sub-samples collected
       from 3 to 10 distinct locations roughly equidistant from each other along an axis.   For
       samples  collected along the foundation dripline, sub-samples should be collected at  least
       2 to 6 feet away from each other.  At other sampling  locations,  samples should be
       collected at roughly equidistant points  along each  axis of an "x" shaped grid.

Sampling Equipment and  Methods

       Samples may  be collected  using a coring  tool  to acquire  the top  1/2  inch (or  1
centimeter) of th« soil surface. Soil coring devices may not be useful in sandy, dry, or friable
soil.  In these cases,  a stainless steel scoop or the lip of the  sample container  itself may be
used.

       If paint  chins  are in the core sample  taken, they should be included as part of the
sample. Paint chips should not be excluded fron. the soil sample, since they are pan of the soil
matrix.   However, there should be no attempt  to oversample  paint chips.   Following the
detailed  sampling procedures outlined in  Residential Sampling  for  Lead:   Protocols for
Sampling Lead Dust and Soil (EPA,  1994), is essential to correctly  apply the guidance provided
here.

Interpreting Results

       Bare coil,  if highly  contaminated  with lead, is thought to be a significant hazard to
children who play on it. It  may also be a significant source of tracked-in or wind-blown lead
that subsequently  contaminates house dust. The level of hazard  is determined by comparing
the sampling results  to the  Section 403 soil lead guidance.

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       If duplicate composite samples  are collected  from the same bare soil  area(s),  the
arithmetic average of the two lead levels should be compared to the Section 403 guidance.  If
non-composited individual samples are taken  instead of composites, within an area expected
to have relatively homogenous lead levels, the  arithmetic average of the individual samples
should be compared to the standard.  However, individual samples  above the  standard might
possibly  indicate  that there  are  inherently large differences  in  lead levels  and that  more
sampling or some remediation should be considered.
SAMPLING AND TESTING FOR LEAD IN PAINT
Where  to Simple

       For a residential unit, all interior rooms, the exterior sides of the unit, and the outside
property around the unit are to be  inspected.  The residence  should be divided into  room
equivalents.  Room equivalents are standard interior rooms, stairways and hallways which are
not usually regarded as rooms, portions of very large rooms, each of the sides of the house,
and the  outside property. Within the  room equivalents, painted components are to be identified
and grouped  by component type, substrate,  and visible color.  For example, if there are four
walls in a room, all made of plaster, and all painted with white paint, these four walls are all
grouped together.  One wall of the four is to be randomly selected to represent the four walls.
In similar fashion, the inspection continues in each room equivalent with the  identification of
unique  combinations of component,  substrate, and visible color. A random representative of
each unique combination is to be sampled and tested  in each room equivalent.

       For each of these designated components,  an area on the component  is to be chosen
which represents the paint on that component.  During the inspection, components which are
accessible  surfaces,  friction surfaces,  impact surfaces,  or have deteriorated  paint are  to be
identified.

How Many Samples

       It is expected that  between 50 to 200 components will  be  identified for testing at a
residential  unit.

       In multifamily housing with more than 20 units, a random sample of units for inspection
is allowed. Units and buildings that have similar construction, floor plans, and painting history
should  be  grouped for sampling  purposes.  Samples may be  selected  for  each group.  In
multifamily  housing  with 20 or  fewer  units,  each unit  is to  be  sampled.   In both  cases,
individual  units are to be  sampled following the guidance on where to sample described for
residential  units. The number of units in the sample should be determined from  Table I,  which

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 is attached.   However, the decision logic for a sample of units  is more complicated  than for
 single residential units, and should be fully grasped  before a sample is selected.

 How to Sample

       The  recommended method for testing  in a residentiaJ  unit at this time is the K shell
 reading from a  portable XRF  instrument.   Substrate  corrections are  to  be made  where
 necessary.   Standard reference material  paint films developed by NIST for usage with  XRFs
 are to be used to demonstrate that XRF instruments are in control.  XRF results are in units
 of milligrams per square centimeter.

       An average of three readings is recommended.  Each reading should be approximately
 15 seconds  with a new source.   Appropriate adjustments in reading time  should be made for
 source age.

       Where portable XRF is not feasible due to a surface being narrow or curved,  where
 greater accuracy is desired, or where comparison to the percent by weight standard  is desired,
 paint samples can be collected  and sent for to a laboratory for analysis.   The paint  samples
 should be collected from a one square inch area.  Care should be taken to collect all the paint
 in the area,  and to minimize the inclusion of substrate material.  Lead in paint  samples
 collected in this way can be reported in  both milligrams per square centimeter and percent by
 weight. If a surface is so deteriorated that XRF is not feasible and a paint sample cannot be
collect from a square inch, then  a strip  of peeling  paint is to be collected. Lead from such a
 sample can  only be reported in percent  by weight  units.
                                                                                    i
                                                                                    ' t
 How to Analyze Paint Samples

       Paint chip* samples should be analyzed by a laboratory recognized by EPA's National
 Lead Laboratory Accreditation Program.  Paint samples should be no more  than 500 milligrams
 in weight.  If the paint samples received by the laboratory are larger than 500 milligrams, the
 laboratory  should homogenize  and subsample the  paint samples  to  select  a subsample of
 approximately 500 milligrams for the analysis.  Results  reported by the laboratory must make
the appropriate adjustment for the subsampling.

 Conclusions

       For single houses and units, conclusions are reached as follows.  XRF results are to be
 corrected for substrate effects where necessary.  Corrected XRF results are divided into three
 categories:   positive, inconclusive, and negative. Reading averages of 1.6 mg/cm2 or more are
 classified as positive;  reading averages or 0.4 mg/cm2  or less are classified  as negative. All
 other reading averages are classified as inconclusive.   K-shell XRF results  in the positive
 category indicate lead  is present at or above 1.0 mg/cm2.  K-shell XRF results in the negative
 category indicate lead  is not present at or above 1.0 mg/cm2. The probability  of false positives
 is currently estimated to be at  least less than 10%, and less than 5%  in most cases.  The

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probability of false negatives is similarly estimated to be at least less than 10%, and less than
5%  in  most cases.    Inconclusive  results  should  be  confirmed  by  laboratory analysis.
Inconclusive XRF results on accessible, impact, friction or  deteriorated  surfaces should be
regarded as positive for lead unless a subsequent laboratory test proves otherwise.

       When paint chip laboratory results are reported in milligrams per square centimeter, a
result greater than or equal to  1.0 is positive for lead.  When the results are in  percent by
weight, a result greater than or  equal to 0.5% is positive for lead.  If laboratory results are in
both units, and at least one result is above the 1.0 mg/cm2 or 0.5% standard,  then  the sample
is positive for lead.

       Locations tested  by XRF or paint chip sampling may represent  other locations.   Refer
back  to  the  original  inspection to determine  the housing components which the samples
represent.   Findings  of positive, negative,  or inconclusive  apply to  all the components
represented by a sample.

       For multi-family  housing of 20 or more units where a sample of units has been selected,
grouped  the  sample  results by  component type, such as "kitchen walls"  or  "doors".   Each
component type group should  consist of at  least 40 samples to the extent this is practical.
Classify  XRF results as  positive, inconclusive, or negative following the rules above. For any
component type with 20% or more positive results,  lead is present at or above the 1.0 mg/sq
on one or more of the components of that type.  If all sample results are negative or all sample
results are less than  1.0 mg/cm2, lead is not  present  at or 1.0 mg/cm2  on any components of
that type.  All other cases are inconclusive and require laboratory testing.

       To do the  laboratory testing, take a paint sample  for all XRF sample results that were
greater than or equal to  1.0 mg/cm2.  If any of these  results are positive, reach the conclusion
that lead is present at or above  1.0 mg/cm2 on at least one component of the type in question.
If no results  are positive, reach  the conclusion that lead is not present at or above  1.0 mg/cm
for any components  of that type.  Results from the sample can  be used to determine which
component types  need abatement or control,  which do not, and which need further testing in
the unsampled units.

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                                   TABLE I
          Number of Units to Be Tested in Multifamily Developments
Number of Units in Building
or Group of li'tnilar Buildings                          Number of Units to Be Tested
      21-26                                                   20
  .  .  27                                                      21
      28                                        '              22
      29-30                                                   23
      31                                                      24
      32                                                      25
      33-34                                                   26
      35                                                      27
      36                                                      28
      37 '                                                     29
      38-39                                                   30
      40-50                                                   31
      51                                                      32
      52-53                                                   33
      54                                                      34
      55-56                                                   35
      57-58                                                   36
      59                                                      37
      60-73                                                   38
      74-75                                                   39
      76-77                                                   40
      /8-79                                                   41
      80-95                                                   42
      96-97                                                   43
      98-99  *•                                                44
      100-117                                                 45
      118-119                                       .          46
      120-138                                                 47
      139-157                                                 48
      158-177                                                4r
      178-197                                                 50
      198-218                                                 5i
      219-258                                                 52
      259-299                                                 53
      300-379                                                 54
      380-499                                                 55
      500-776                                                 56
      777-1004                                               57
      1005-1022                                               58
      1023-1039                                               59

For buildings or groups of similar buildings with 1,040 units or more, test 5.8 percent of the
number of units, rounded to the nearest unit. EXAMPLE: If there are 2,170 units, 5.8 percent is
125.86 units, so 126 units should be tested.

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                           DUST CLEARANCE TESTING
                                                                         July 1994
BACKGROUND

       Section 403 of the Residential Lead-Based Paint hazard Reduction Act of 1992
requires EPA to promulgate regulations which identify lead-based paint hazards, lead-
contaminated dust, and lead-contaminated soil.  The purpose of this document is to
summarize clearance testing procedures to identify lead dust hazards that may remain after
lead abatements  or application of interim controls.

WHO SHOULD SAMPLE

       Clearance testing for dust should be conducted after lead abatements or after
application of interim controls.  Clearance testing should be conducted by a party
independent of the person or organization that completed the abatement or interim controls.

WHEN TO SAMPLE

       Sampling of dust should take place at least one hour after completion of all
abatement and interim control work, including clean-up.  All interior rooms or areas  and
exterior areas should be visually clean before collecting dust samples.  If this is not the
case, clean the rooms and areas before starting dust collection for clearance testing.

WHERE  TO SAMPLE

       Identify the interior rooms or areas and exterior areas of the residence where
abatements or interim controls were carried out.  If there was an  interior containment area,
most of the clearance sampling  should be conducted  within the containment  area.  If there
was no interior containment area, all interior rooms or areas should be sampled.  Designate
rooms or areas in the interior for sampling.  An interior area is a portion of a the residence
that is equivalent to a room, even though it is  not ordinarily regarded as such. Hallways
and stairways are examples of areas in a house.  In addition, very large rooms should be
divided into areas.

       If on-site paint removal took place  in the interior, collect one floor sample, one
interior window sill sample, and one exterior window sill sample from each  of the interior
rooms or areas  designated for sampling.  If no on-site paint removal took place in the
interior, select one floor sample  and one window sample, either a interior or exterior sill, in
each room or area designated for sampling.

       If there were  any exterior abatements or interim controls,  select one exterior window
sill and one other horizontal surface in a living area or near an entryway for testing,
preferably from the sides  or exterior areas of the house where abatements  or controls were
applied.  A porch railing or the top step of a stairway are  examples of horizontal  surfaces
on the exterior.

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       If there was an interior containment area, collect one floor sample outside the
containment area but within 10 feet of the airlock.

HO\V MANY SAMPLES

       The total number of samples will depend on the number of interior rooms, the
presence of an interior containment area, whether there was any exterior work, the number
of windows present, and the presence of horizontal  surfaces on the exterior.

       For example, consider a single family house with 8 interior rooms and areas. In this
case suppose abatement had taken place in 4 of the interior rooms, and on the front and
back of the house.  There was no interior containment  area, and on-site removal of paint
took place  in the interior. All rooms had windows.  There would be 26 dust samples for
this house, 3 from each of thw 8 interior rooms or areas, and 2 from the exterior.

       As another example, consider another house with 8 interior rooms or areas. Suppose
abatement had taken place in the interior, in 5 rooms, with a containment separating these 5
rooms from the rest of the house.  Suppose no on-site removal of paint had taken place.
There would be 11 interior dust samples, 2 from each of the 5 rooms were abatements were
done, plus one floor sample with"i 10 feet of the containment  area.  If there had been  any
exterior work, 2 dust samples would have been collected from the exterior.

       In a multi-family  housing of more than 20 units, random sampling of units for
clearance testing is allowed.  Units and buildings that have  similar construction and were
cleaned in the same manner should be  grouped for sampling purposes.   Samples  may be
selected  for each group.  The number of units in the sample should be derived from Table
I, which is attached.  In this case, guidance on where to sample for the selected units is the
same as  for an individual house.  However,  if any component  in the sample of units fails
clearance, that component, in all the unsampled units, must be re-cleaned,  as well the
specific components that failed clearance in sampled units.  The significance of this aspect
of clearance failure should be grasped before selecting a sample of units.

HOW TO SAMPLE

       Draw or obtain a floor plan of the house or unit. Rooms,  areas, and locations of
windows should be clearly marked on the floor plan. If there  were exterior abatements,
identify  the window exterior sills and horizontal surfaces closest to the exterior areas that
were worked on.  Using information about the abatement or interim control applications,
designate interior rooms and areas and exterior areas for sampling.

       Using the floor plan, go through the residence and make selections of where to
sample.  For floors, divide each room or area into three segments, randomly select one of
the segments, and then, within the segment, randomly  select either a position near a wall or
a position near the center. If there is one window in a room or area, that window should be

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sampled.  If there is more than one sample, randomly  select an interior window sill and/or
and exterior window sill.  Note that if there are two or more windows in a room, the
interior and exterior sills may come from different windows.

       The basic method for collecting dust clearance  samples is the wipe method.  Other
dust collection  methods may be used provided the user establishes comparability to the
wipe method.

       To collect floor samples, use a template or tape to mark off one square foot within
the floor location selected.   Use a wipe method to collect dust within the template or taped
area.  Clean the template between samples if using a non-disposable template.
Take other appropriate steps to avoid contamination  of samples.

       For sampling interior and  exterior window sills and exterior horizontal surfaces, use
tape to mark the specific section  to be sampled.  Be sure what is delineated by the tape can
be measured.

       After collection of dust, fold the wipe  and place it in a clean glass or plastic
container.  Label the container so that sample can be associated with the location from
which it was collected.  Measure all sampling areas  not delineated by the template, and all
cases indicate the sampling  area on each label for each container.

HOW  TO ANALYZE  DUST SAMPLES

       Dust samples are to be analyzed for "total lead", not "bioavailable lead".  Sai/.ples
should be analyzed at a laboratory recognized as proficient for lead  in dust analysis by the
EPA National  Lead Laboratory Accreditation  Program (NLLAP).

CONCLUSIONS

       At this time, the standards for clearance are 100 ug/fr for floors,  500  ug/fr  for
interior window sills, and 800 ug/ft- for exterior window sills and exterior horizontal
surfaces.  These numbers are for wipe samples.  If a collection method other than the wipe
method is used, the user is responsible  for providing comparable standards for clearance.

       Samples which are less than the appropriate standard are said to have passed
clearance, and  all rooms or  areas represented  by those samples have passed clearance.

       Samples above or equal to the appropriate standard have failed clearance,  and all
rooms or areas represented  by those samples are said to have failed.

       For samples that have  failed, the components represented by those samples (floors,
interior window sills, exterior window sills, exterior horizontal surfaces,  or interior areas
outside a containment area) must be re-cleaned and  re-tested.   The process continues until

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clearance  is obtained for all components.  In addition, if a sample outside a containment
area fails  clearance,  collect additional floor  samples outside the containment  area, at a
further distance  from the airlock, during the re-testing.

RE-EVALUATION  SCHEDULE

       When lead-based paint is removed during abatement,  successful clearance testing
after application is all that is recommended.  When lead-based paint remains at the
residence, re-evaluation testing is recommended in addition to clearance testing.  For
enclosures, re-evaluation testing is recommended ten years after treatment.  For
encapsulation, re-evaluation testing is recommended one year after application, and then
every three years afterwards.  For interim controls, re-evaluation testing is recommended
every 12 months after application.  If a mixture of methods is used in a room or area, the
most stringent schedule for re-evaluation testing is recommended.

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                                   TABLE I
          Number of Units to Be Tested in Multifamily Developments
Number of Units in Building
or Group of Similar Buildings                          Number of Units to Be Tested
      21-26                                                   20
      27                                                      21
      28                                                      22
      29-30                                                   23
      31                                                      24
      32                                                      25
      33-34                                                   26
      35                                                      27
      36                                                      28
      37  '                                                    29
      38-39                                                   30
      40-50                                                   31
      51                                                      32
      52-53                                                   33
      54                                                      34
      55-56                                                   35
      57-58                                                   36
      59                                                      37
      60-73                                                   38
      74-75                                                   39
      76-77                                                   40
      78-79                                                   41
      80-95                                                   42
      96-97                                                   43
      98-99  -.                                                44
      100-117                                                45
      118-119                                                46
      120-138                                                47
      139-157                                                48
      158-177                                                49
      178-197                                                50
      198-218                                                51
      219-258                                                52
      259-299                                                53
      300-379                                                54
      380-499                                                55
      500-776                                                56
      777-10O4                                               57
      10O5-1022                                              58
      1023-1039                                              59

 For buildings or groups of similar buildings with 1,040 units or more, test 5.8 percent of the
 number of units, rounded to the nearest unit. EXAMPLE: If there are 2,170 units, 5.8 percent is
 125.86 units, so 126 units should be tested.

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