Authority: IC 13-14-8; IC 13-15-1-2; IC 13-15-2-1; IC 13-18-3-1; IC 13-18-4-1

Affected: IC 13-11-2; IC 13-13-5-1; IC 13-18-2; IC 15-16-4; IC 15-16-5

Sec. 9. A PWS must comply with the following provisions for the separation of a production well from a potential or an existing source of contamination or damage, except replacement wells allowed under section 9.1 of this rule:

(1) The sanitary setback from a potential or an existing source of contamination for the construction of a PWS production well is the circular area within a radius as stated in the following table:

(2) A well subject to automatic disinfection treatment before entering the water distribution system must meet a sanitary setback of at least one hundred (100) feet. To meet this provision at systems using chlorine or chlorine dioxide, the:

(A) free chlorine residual disinfectant concentration in the water entering the water distribution system cannot be less than two-tenths (0.2) milligrams per liter (mg/l) for more than four (4) hours; and

(B) residual disinfectant level in the water distribution system cannot be undetectable in more than five percent (5%) of the samples collected each month in accordance with 40 CFR 141.72* and 40 CFR 141.132*.

Systems using disinfectants other than chlorine or chlorine dioxide must maintain an equivalent level of disinfection as determined by the commissioner.

(3) A determination of favorable hydrogeological conditions may be approved by the commissioner after the submission of a report that is signed, dated, and sealed by a licensed professional geologist, or other person legally authorized to perform geological services, or a professional engineer who applies geology to the practice of engineering. The report must include the following information:

(A) The thickness, vertical permeability, and spatial continuity of a protective layer or layers overlying the production aquifer.

(B) The local and regional geologic conditions of the well site area.

(C) The relative susceptibility to contamination of the proposed production aquifer.

(4) A well discharging into the inlet side of a surface water treatment process plant that meets the requirements of 40 CFR 141, Subpart H* and 40 CFR 141, Subpart P* is not subject to a sanitary setback requirement.

(5) The sanitary setback is subject to the following additional requirements:

(A) The separation distance between at least two (2) wells of a PWS must be maintained in accordance with the following:

(i) A production well with a pumping capacity of less than seventy (70) gpm must not be located closer than fifty (50) feet from another production well.

(ii) A production well with a pumping capacity of greater than or equal to seventy (70) gpm must not be located closer than one hundred (100) feet from another production well.

(iii) A PWS drinking water well that is part of a transient noncommunity PWS must not be closer than fifty (50) feet, regardless of the capacity of pumping equipment, from another well in the system.

(B) A storm or sanitary sewer must not be located within the sanitary setback of a production well unless the storm or sanitary sewer is:

(i) more than fifty (50) feet, as measured from all directions, from a PWS production well; and

(ii) constructed in accordance with 327 IAC 8-3.2-8, 327 IAC 8-3.2-17(a), and 327 IAC 8-3.2-17(b).

(C) The sanitary setback for a PWS production well must conform to the following requirements concerning transportation routes:

(i) A sanitary setback does not apply to roadways, paved surfaces, and parking areas for service vehicles that:

(AA) service the proposed well, pump, and appurtenances;

(BB) are owned or controlled by the PWS; and

(CC) are restricted from access by the public.

(ii) Roadways, paved surfaces, and parking areas must not be located within fifty (50) feet of a well if they are part of the following:

(AA) Residential subdivisions.

(BB) Apartment communities.

(CC) Mobile home parks.

(DD) Recreational parks.

(iii) A transportation route, such as a railway, roadway, paved area, or parking area, including paved or unpaved roadway or surface areas, must not be located within the sanitary setback as measured from the outside edge of the well casing to the traveled portion of the transportation route, if the transportation route is:

(AA) accessible in full or in part for commercial or industrial transportation activities; or

(BB) listed as a hazardous material route.

(D) The distance between the location of a PWS production well casing and a surface water body must be at least twenty-five (25) feet, including for:

(i) a stream;

(ii) a pond;

(iii) a lake;

(iv) a reservoir;

(v) an impoundment; or

(vi) a drainage ditch.

(6) The commissioner may modify the requirements of a sanitary setback, control area, or separation distance to an alternative area or distance so long as the alternative area or distance can provide the same factor of safety for filtering pathogenic contaminants as the sanitary setback or separation distance. The commissioner's decision to allow an alternative sanitary setback or separation distance must be based on the following conditions:

(A) The applicant's submission of a report describing the following:

(i) Treatment processes.

(ii) Geologic features.

(iii) Additional water monitoring provisions.

(iv) Other means of providing pathogenic contaminant filtration.

(v) Other means of mitigating contaminant sources relative to the location of the well.

(B) The report required by clause (A) must be signed and sealed by a professional engineer, licensed well driller, or licensed professional geologist.

(7) A supplier of water to a PWS must own or control the sanitary setback by recorded deed, easement, or long term lease. A small nontransient noncommunity PWS or small transient noncommunity PWS must own or control a fifty (50) foot sanitary setback by recorded deed, easement, or long term lease.

(8) The use, application, storage, mixing, loading, and transportation of pesticides in accordance with IC 15-16-4, IC 15-16-5, and the rules and guidance thereunder, developed by the Indiana pesticide review board and the office of the state chemist, may occur within the sanitary setback if the following requirements are met by the PWS:

(A) The production well casing is constructed of steel in accordance with section 16 of this rule.

(B) The product is stored within a containment system:

(i) designed;

(ii) constructed;

(iii) operated; and

(iv) maintained;

to contain spills or leaks.

(9) Water treatment chemicals and fuels for water production equipment containing contaminants that are not registered pesticides regulated under the SDWA, 42 U.S.C. 300f et seq., as amended August 6, 1996**, may be used, stored, mixed, loaded, and transported within the standard sanitary setback if the following conditions are met:

(A) The production well casing is constructed of steel in accordance with section 16 of this rule.

(B) The product is stored:

(i) within a containment system designed, constructed, operated, and maintained to contain spills or leaks; and

(ii) in an underground or aboveground storage tank that is in conformance with applicable federal, state, and local laws and regulations.

*These documents are incorporated by reference. Copies may be obtained from the Government Publishing Office, www.gpo.gov, or are available for review at the Indiana Department of Environmental Management, Office of Legal Counsel, Indiana Government Center North, 100 North Senate Avenue, Thirteenth Floor, Indianapolis, IN 46204.

**The Safe Drinking Water Act, 42 U.S.C. 300f et seq., as amended August 6, 1996, can be found at https://www.govinfo.gov/app/collection/uscode/1996/title42/chapter6.

(Water Pollution Control Division; 327 IAC 8-3.4-9; filed Jun 17, 1999, 1:50 p.m.: 22 IR 3371; readopted filed Jan 10, 2001, 3:23 p.m.: 24 IR 1518; errata filed Feb 6, 2006, 11:15 a.m.: 29 IR 1937; filed Apr 24, 2006, 3:00 p.m.: 29 IR 2963; readopted filed Nov 21, 2007, 1:16 p.m.: 20071219-IR-327070553BFA; readopted filed Jul 29, 2013, 9:21 a.m.: 20130828-IR-327130176BFA; errata filed Jul 31, 2017, 11:06 a.m.: 20170809-IR-327170349ACA; readopted filed Jun 14, 2019, 1:59 p.m.: 20190710-IR-327190246BFA; readopted filed Oct 18, 2024, 1:57 p.m.: 20241113-IR-327230810RFA; filed Nov 24, 2025, 9:07 a.m.: 20251224-IR-327240428FRA)