567—148.5 (455B) Site classification.
	 148.5(1) General requirement. Iowa Code section 455B.427(3) requires the director to assess the relative priority of the need for action at each site to remedy environmental and health problems resulting from the presence of hazardous wastes or hazardous substances at the sites. Every site must be placed in one of five classifications. However, sites which are reclassified “e” shall be removed from the registry.
	 148.5(2) Criteria for determining site classification. The criteria described in 148.5 (3) to 148.5(7) shall be used to help determine the appropriate classification or reclassification for sites on the registry. The department shall propose the recommended site classification after the development of the site information package described in 148.4(2).
	 148.5(3) Classification “a.” Causing or presenting an imminent danger of causing irreversible or irreparable damage to the public health or environment—immediate action required. The documented release of contaminants is causing or the imminent threat of release of contaminants is likely to cause one of the following conditions:
	  a.   	 Exposure above groundwater action levels in a drinking water supply used for human or animal consumption.
	  b.   	 Exposure above health guidelines through inhalation, ingestion, or with direct contact with soil or water.
	  c.   	 Exposure resulting in the threat of acute toxic impacts on aquatic life or irreversible impact on the environment.
	 148.5(4) Classification “b.” Significant threat to the environment—action required. The documented release of contaminants is causing or the potential release of contaminants is likely to cause one of the following conditions:
	  a.   	 Groundwater contamination above groundwater action levels.
	  b.   	 The likely possibility of exposure above health guidelines through inhalation, ingestion, or with direct contact with soil or water.
	  c.   	 Exposure resulting in the threat of chronic toxic impacts on aquatic life or significant impact on the environment.
	 148.5(5) Classification “c.” Not a significant threat to the public health or environment—action may be deferred. There is no documented release of contaminants to groundwater above groundwater action levels and the potential for release under current site conditions is unlikely to cause a significant threat to the environment.
	 148.5(6) Classification “d.” Site properly closed—requires continued management. The site has been properly closed under an EPA- or state-approved remedial action plan in which the hazardous wastes or hazardous substances were removed, treated, or contained on site and one of the following conditions is required:
	  a.   	 Continued environmental monitoring to determine the adequacy of the remedial action.
	  b.   	 Continued site management to maintain the integrity of the physical closure structures.
	  c.   	 Continued control of site to prevent inappropriate use of the property.
	 148.5(7) Classification “e.” Site properly closed, no evidence of present or potential adverse impact—no further action required. The site meets one of the following conditions:
	  a.   	 The site has undergone complete cleanup under an EPA- or state-approved closure plan and no monitoring, structural maintenance, site access control, or other action is required.
	  b.   	 The site has undergone other action which demonstrates that no further monitoring, structural maintenance, site access control, or other action is required.
	 148.5(8) Department of public health (DPH) classification recommendation. As required by Iowa Code subsection 455B.427(3), the department shall work in cooperation with the DPH in making assessments of the relative priority classification on matters relating to public health. The department’s proposed classification and a copy of the site information package shall be submitted with the request for the DPH site classification recommendation.