Section 299.51013. Unacceptable exposure; mitigation.

Rule 1013. (1) Except as provided in subrule (6)  of  this  rule, the requirements of section 20107a(1)(b) of the act and  these  rules  to mitigate unacceptable exposure shall  be  satisfied  if  a person does all of the following:

(a)   Eliminates the exposure or reducing the exposure to the degree that it is no longer unacceptable as that term is described in subrules (3), (4), and (5) of this rule.

(b)      Undertakes response activity at the property as necessary to mitigate off- property risks resulting from erosion of surface soils at  the property or from dispersion of particulate or volatile hazardous  substances in surface soils at the property.

(c) Complies with R 299.51005, R 299.51009, R 299.51011, and  R     299.51015 to R

299.51019 with regard to conditions at the property.

(2)    In evaluating compliance with section 20107a(1)(b) of  the  act, exposure pathways shall be considered pertinent only if they are or may be complete in light of the intended use of the property and the features of the property, including potential exposure barriers such as  structures  or pavement.

(3)   Except as provided in subrules (4) and (5) of this rule, exposure to hazardous substances is an unacceptable exposure for the  purposes  of section 20107a(1)(b) of the act if concentrations of hazardous substances to which persons may be exposed exceed an applicable criterion developed by the department under section 20120a(1)(a) to (e) of the act.

(4)     A site-specific evaluation may be conducted to document that conditions at a property do not result in an unacceptable exposure. In these cases, comparison of exposure concentrations to criteria developed by the department under section 20120a(1)(a) to (e) of the act is  not required.  Except  as provided in subrule (5) of this rule,   an  evaluation relied  upon  under   this  subrule  shall   be  consistent  with the risk management objectives set forth in section 20120a of the act and risk assessment methods acceptable to the department.

(5)   As described in this subrule, a site-specific evaluation to document that conditions at the property do not result in an  unacceptable exposure through inhalation of   indoor  air  may  be   based    on   a demonstration   of compliance with 1974 PA 154, MCL 408.1001 et seq., and the rules promulgated under 1974 PA 154. This subrule applies  only  when   all of the following conditions are satisfied:

(a)    The risk being evaluated results from inhalation by   workers  of hazardous substances in indoor air within an active commercial or industrial workplace that is regulated by 1974 PA 154, MCL 408.1001 et seq.,  and the  rules promulgated under 1974 PA 154.

(b)    The exposure to hazardous substances from environmental contamination is a portion of the exposure to which workers are  otherwise   subject from process- related sources of the same hazardous substance.

(c)   The risk to the non-worker population, if any, from  inhalation  of indoor air  at the  property   has  been  evaluated   according  to    the requirements  of subrule (3) of this rule or a site-specific evaluation has been conducted for the non-worker population according   to  risk  assessment methods acceptable   to the department, and the risk is  not

unacceptable   on the   basis   of    the   risk management objectives set forth in    section 20120a of the act.

(6)   If the hazardous substances present at the property may present an unacceptable exposure   to   utility   workers    or   other     persons conducting activities at the property in an easement, under the terms of a utility franchise, or pursuant to severed subsurface mineral rights or severed subsurface formations, then the owner or operator may satisfy his or her obligation to mitigate unacceptable exposures to the utility workers or other persons by providing written notice, by a  method  that provides proof  of  delivery,   of  the  general   nature  and  extent    of contamination   and potential unacceptable exposures to all of the following:

(a)   Easement holders of record.

(b)   Utility franchise holders of record.

(c)   The owner or operator of all public utilities that serve the property.

(d)      Owners or lessees of severed  subsurface   mineral  rights  or subsurface formations. If the person described in subdivisions (a) to (d) of this subrule is not an individual, then the notice shall be provided to the chief executive officer of the organization. The notice required under this rule shall be provided as soon as the exigencies of the situation require, but not  later  than  9 months after the effective date of this amendatory rule or the deadline set forth in R 299.51003(6), whichever is applicable.

(7)   Upon request of a person to whom information is  provided  under subrule (6) of this rule, the owner or operator of property who provided notice under subrule (6) of this  subrule  shall  provide  all  available information  about conditions at the property that he or she owns or operates which are relevant to the activities of the person who received notice under subrule (6) of this rule. The owner or operator of a property who is subject to section 20107a of the act  shall   also  provide,  to   other  persons conducting activities at the property  with  the   knowledge  or  permission of  the  owner or operator, information about conditions at the property that are relevant to the person's activities at the property.

History: 1999 MR 2, Eff. Mar. 11, 1999; 2002 MR 24, Eff. Dec. 21, 2002.