Current through Register 1531, September 27, 2024
Risk Characterizations for Imminent Hazard Evaluations shall
be conducted separately for safety, human health, and the environment,
depending on the type of condition that triggered the need for the evaluation,
in accordance with the following methods:
(1) The characterization of the risk of harm
to safety shall be conducted as described in
310
CMR 40.0960. The conditions at the disposal
site pose an Imminent Hazard based on safety concerns if a condition of no
significant risk to safety has not been achieved at the disposal site under
conditions which actually exist or are about to occur.
(2) The characterization of the risk of harm
to human health shall be conducted using Method 3, as described in
310
CMR 40.0993.
(a) The toxicity information used to
characterize risk shall be consistent with the type and duration of exposure
under evaluation, and shall be clearly identified and documented. Primary
consideration shall be given to information developed by the Massachusetts
Department of Environmental Protection for the purpose of conducting such risk
assessments. Examples of such toxicity information include:
1. Reference Doses and Reference
Concentrations; and
2. Carcinogenic
Slope Factors and Unit Risk values.
(b) The conditions at the disposal site pose
an Imminent Hazard based upon the potential for carcinogenic health effects if,
for the oil and/or hazardous material evaluated and for each receptor, the
estimated Excess Lifetime Cancer Risk is equal to or greater than a cancer risk
limit which is an Excess Lifetime Cancer Risk equal to
one-in-100,000.
(c) The conditions
at the disposal site pose an Imminent Hazard based upon the potential for
non-cancer health effects if, for the oil and/or hazardous material evaluated
and for each receptor, the non-cancer risk calculated is equal to or greater
than a non-cancer risk limit of:
1. a Hazard
Index (or equivalent ratio of exposure) equal to one for oil or hazardous
materials that have the potential to cause serious effects (including, but not
limited to, lethal, developmental, or neurological effects) following
short-term exposures, for example lead or cyanide; and
2. a Hazard Index equal to ten for all other
oil or hazardous materials.
(d) A release to the environment which
produces readily apparent effects to human health poses an Imminent Hazard. A
quantitative evaluation of such exposures is not required.
(e) The mathematical equations used to
calculate the risk estimates shall be clearly presented and
documented.
(3) The risk
of harm to the environment shall be characterized based on the data collected
pursuant to the response action being performed and the site, receptor and
exposure information identified in
310
CMR 40.0995. The following conditions shall
constitute an Imminent Hazard to the environment:
(a) evidence of stressed biota attributable
to the release at the disposal site including, without limitation, fish kills
or abiotic conditions; or
(b) a
release to the environment of oil or hazardous material which produces
immediate or acute adverse impacts to freshwater or saltwater fish
populations.
(4) The
documentation of the Imminent Hazard Evaluation shall clearly state whether the
conditions at the disposal site pose an Imminent Hazard based upon the criteria
described in 310 CMR 40.0955(1) through (3).
