I. PURPOSE

This TAGM describes the policy and procedure to be
followed by Division of Hazardous Substances
Regulation, Bureau of Radiation staff in evaluating
cleanup plans for soils contaminated with radioactive
materials.

The purpose of this cleanup guideline is to provide
for

(1)  protection of public health and the environment,
     and

(2)  consistency in implementing remedial actions at
     sites contaminated with radioactive materials.

II. POLICY

The total effective dose equivalent to the maximally-
exposed Individual of the general public, from
radioactive material remaining at a site after cleanup,
shall be as low as reasonably achievable and less than
10 mrem above that received from background levels of
radiation in any one year.

The radiation dose received from an exposure to soils
contaminated by radionuclides will strongly depend on
the time of exposure and pathways by which the
radionuclides or their decay products can come in
contact with an individual.  For this reason, the
estimated annual dose resulting from exposure to any
residual radionuclides in the contaminated area is the
basis for establishing site-specific cleanup criteria.
The dose estimate is to be based on the contaminating
radionuclides, but not on background concentrations of
any radionuclides that may be at the site.  Background
radiation refers to

(1)  local area concentrations of naturally occurring
     radionuclides,

(2)  cosmic radiation, and

(3)  radionuclides of anthropogenic origin which have
     been regionally dispersed and are present at low
     concentrations (such as fallout from the testing
     of nuclear weapons).

III. PROCEDURE

The process of determining the appropriate cleanup
requirements will generally involve measurements of
radioactivity at the site, laboratory analysis of soil
samples for concentrations of radioactive materials,
modeling of expected doses based on the measurements
and analyses performed, and evaluation of site
remediation alternatives.  The modeling will require
determination of site characteristics critical to the
migration of radionuclides, and will need to be
referenced to reasonable scenarios for current and
plausible future uses of the land.  consideration of
the time period during which the radioactive material
is expected to persist at the site will be important In
the selection of scenarios for land use.  The estimated
dose limit of 10 mrem/year refers to land released for
unrestricted use.  If unrestricted use scenario
calculations result in dose estimates that are greater
than 10 mrem/year, it may be necessary to invoke
institutional controls and/or deed restrictions so that
actual doses from allowed uses are not likely to exceed
10 mrem/year.

A.   Dose Analysis Methods

     Analysis methods used must be acceptable to the
     DEC Division of Hazardous Substances Regulation,
     Bureau of Radiation.  The methods used should be
     appropriate to the complexity of the contaminated
     site and to the potential for harm.  The primary
     criterion is that the analysis yield conservative
     results, i.e., the results of the analysis, must
     predict doses no lower than are likely to actually
     occur.  This principle should be applied to both
     the analysis methods and to the site-specific
     inputs required for any models used in the
     evaluation.

All reasonable pathways of exposure shall be
considered when determining the estimated dose to
individuals.  Approval of the procedures used in,
and the interpretation of, each step of the
analysis must be obtained from NYSDEC.  The steps
to be followed are:

1.   Perform a site assessment.  This involves
     determining exposure levels at the site, the
     extent of the contamination, and
     concentrations of radionuclides in the
     contaminated areas.  Care must be taken that
     the appropriate instrumentation Is used for
     detecting radiation at the site (gamma, beta,
     alpha, or neutrons). Concentration profiles
     as a function of depth in the soil should be
     determined.  Where possible, the chemical and
     physical forms of the radionuclides should be
     determined.  It should be possible from this
     data to characterize the locations and
     concentrations of all radionuclides which can
     significantly contribute to the dose
     potentially received from the site.  When
     modeling the site characteristics, and the
     migration of radionuclides within and from
     the site, it will be necessary to show that
     the site parameters used will cause the dose
     estimates to be conservative.

During on-site investigation, staff and
contractors must abide by all appropriate
requirements and Departmental policies
related to personal protection and by any
applicable health and safety plans.  At sites
where non-radioactive contaminants are known
to be present, staff should contact
appropriate persons from other involved
Bureaus, Divisions, or Agencies as to health
and safety and coordination of activities.
If non-radioactive chemical contamination
(where not previously known) is suspected at
a site, be it by observation and/or analysis,
the appropriate regulatory staff should be
notified.

Provide a review of current land use and a
rationale for potential use of the site.  Use
this information to estimate possible
occupancies for the site and review how
different plausible uses of the site can
contribute to exposures.  Keep in mind that
the maximally exposed individual of concern
is a member of the general public not
associated with the use of radioactive
materials.  This is usually a resident, but
may also be a worker at a business not
licensed to used radioactive materials.
Radiation exposure to workers at facilities
with radioactive materials is regulated by
the licensing agency under the New York State
Industrial Code (New York State Department of
Labor) or the New York State Sanitary Code
(New York State Department of Health).

Analyze all reasonable pathways.  Only when
pathways can be shown to contribute
insignificantly to the dose, can they be
eliminated from further consideration.
Pathways that must be considered are:

(a)  Doses from direct exposure to radiation
     emitted from the contaminated soil and,
     where applicable, from contaminated
     ground or surface water.

(b)  Doses from internal exposure - including
     inhalation of contaminated dust
     (including radon progeny if present),
     ingestion of contaminated soil,
     ingestion of food raised on contaminated
     soil, and Ingestion of drinking water
     (both aquifer and surface waters) or
     contaminants from irrigation water.

Analysis of Remediation Alternatives

Remediation techniques should be evaluated for
effectiveness at-meeting the 10 mrem/year dose
limit, at keeping radiation doses as low as
reasonably achievable, and at minimizing the
creation of radioactive waste.  If site
remediation is needed to achieve the 10 mrem/year
dose limit, it will be necessary to prepare a work
plan that is acceptable to NYSDEC and other
cognizant agencies (NYSDOL, NYSDOH).

Acceptable remediation procedures might Include:

(1)  Removal of contaminated soil for disposal at
     a licensed facility.

(2)  Isolation of contamination such as covering
     the contamination with clean soil.  This
     technique may be acceptable for short-lived
     isotopes assuming that restrictions to land
     use are used until the radionuclides no
     longer pose a threat.

(3)  Other remediation techniques, if applicable,
     considered and approved on a case-by-case
     basis.

Remediation alternatives should be evaluated for exposures
which will occur to workers, staff and the general public
during corrective action/remedial activities.  Appropriate
health and safety plans should be prepared or referenced
for construction and monitoring activities (see also
item C.(1) below).

Remedial alternatives should also be evaluated for the
potential to cause significant damage to sensitive
environmental or historical areas (see also
item C.(2) below).

Special consideration must be given to sites contaminated
with non-radioactive chemicals as to remedial alternatives
and disposition of the resultant hazardous or "mixed"
waste.

Before a site can be released for unrestricted use it will
be necessary to confirm that the approved work plan has
been completed successfully.  This confirmation will
include measuring exposure rates and/or measurements of
residual radionuclide concentrations.  The final modeling
step will need to show that release of the site, with any
radionuclide concentrations still remaining after
remediation, will not cause the dose limit to be exceeded.

Alternative Procedures

There may be incidents/situations whereby:

(1)  the health and safety of individuals involved in a
     cleanup may necessitate acceptance of a dose greater
     than 10 mrem/year to the maximally exposed individual,
     or

(2)  the cleanup may cause irreversible destruction or loss
     of environmental habitat.

In such situations, remedial options will be evaluated on a
case-by-case basis.  Final decisions will be made by the
Chief, Bureau of Radiation.

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