Ill. Admin. Code tit. 35 § 734.445

Current through Register Vol. 48, No. 49, December 6, 2024

Section 734.445 - Water Supply Well Survey

a) At a minimum, the owner or operator must conduct a water supply well survey to identify all potable water supply wells located at the site or within 200 feet of the site, all community water supply wells located at the site or within 2,500 feet of the site, and all regulated recharge areas and wellhead protection areas in which the site is located. Actions taken to identify the wells must include, but not be limited to, the following:

1) Contacting the Agency's Division of Public Water Supplies to identify community water supply wells, regulated recharge areas, and wellhead protection areas;

2) Using current information from the Illinois State Geological Survey, the Illinois State Water Survey, and the Illinois Department of Public Health (or the county or local health department delegated by the Illinois Department of Public Health to permit potable water supply wells) to identify potable water supply wells other than community water supply wells; and

3) Contacting the local public water supply entities to identify properties that receive potable water from a public water supply.

b) In addition to the potable water supply wells identified pursuant to subsection (a) of this Section, the owner or operator must extend the water supply well survey if soil or groundwater contamination exceeding the Tier 1 groundwater ingestion exposure route remediation objectives of 35 Ill. Adm. Code 742 for the applicable indicator contaminants extends beyond the site's property boundary, or, as part of a corrective action plan, the owner or operator proposes to leave in place soil or groundwater contamination exceeding the Tier 1 groundwater ingestion exposure route remediation objectives of 35 Ill. Adm. Code 742 for the applicable indicator contaminants and contamination exceeding such objectives is modeled to migrate beyond the site's property boundary. At a minimum, the extended water supply well survey must identify the following:

1) All potable water supply wells located within 200 feet, and all community water supply wells located within 2,500 feet, of the current or modeled extent of soil or groundwater contamination exceeding the Tier 1 groundwater ingestion exposure route remediation objectives of 35 Ill. Adm. Code 742 for the applicable indicator contaminants; and

2) All regulated recharge areas and wellhead protection areas in which the current or modeled extent of soil or groundwater contamination exceeding the Tier 1 groundwater ingestion exposure route remediation objectives of 35 Ill. Adm. Code 742 for the applicable indicator contaminants is located.

c) The Agency may require additional investigation of potable water supply wells, regulated recharge areas, or wellhead protection areas if site-specific circumstances warrant. Such circumstances must include, but not be limited to, the existence of one or more parcels of property within 200 feet of the current or modeled extent of soil or groundwater contamination exceeding the Tier 1 groundwater ingestion exposure route remediation objectives of 35 Ill. Adm. Code 742 for the applicable indicator contaminants where potable water is likely to be used, but that is not served by a public water supply or a well identified pursuant to subsections (a) or (b) of this Section. The additional investigation may include, but is not limited to, physical well surveys (e.g., interviewing property owners, investigating individual properties for wellheads, distributing door hangers or other material that requests information about the existence of potable wells on the property, etc.).

d) Documentation of the water supply well survey conducted pursuant to this Section must include, but not be limited to, the following:

1) One or more maps, to an appropriate scale, showing the following:

A) The location of the community water supply wells and other potable water supply wells identified pursuant to this Section, and the setback zone for each well;

B) The location and extent of regulated recharge areas and wellhead protection areas identified pursuant to this Section;

C) The current extent of groundwater contamination exceeding the Tier 1 groundwater ingestion exposure route remediation objectives of 35 Ill. Adm. Code 742 for the applicable indicator contaminants; and

D) The modeled extent of groundwater contamination exceeding the Tier 1 groundwater ingestion exposure route remediation objectives of 35 Ill. Adm. Code 742 for the applicable indicator contaminants. The information required under this subsection (d)(1)(D) is not required to be shown in a site investigation report if modeling is not performed as part of site investigation;

2) One or more tables listing the setback zones for each community water supply well and other potable water supply wells identified pursuant to this Section;

3) A narrative that, at a minimum, identifies each entity contacted to identify potable water supply wells pursuant to this Section, the name and title of each person contacted at each entity, and field observations associated with the identification of potable water supply wells; and

4) A certification from a Licensed Professional Engineer or Licensed Professional Geologist that the water supply well survey was conducted in accordance with the requirements of this Section and that the documentation submitted pursuant to subsection (d) of this Section includes the information obtained as a result of the survey.

Ill. Admin. Code tit. 35, § 734.445