Section 327 IAC 8-3.4-24 - Disinfection procedure requirementsAuthority: 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
Sec. 24.
(a) The disinfection procedures described in this section shall be performed with one (1) of the following approved forms of chlorine: (1) Calcium hypochlorite.(b) Gravel installed in a new production well must be chlorinated by use of the following method: (1) Silica gravel for gravel pack shall be disinfected with calcium hypochlorite or sodium hypochlorite before installation in a well at a rate that will produce a liquid concentration of at least fifty (50) milligrams per liter (mg/l) as the gravel is installed.(2) The gravel, disinfected according to subdivision (1), shall be fed into a gravel chute or tremie to completely fill the annular void outside the well casing to the top gravel pack level.(3) Chlorine shall be added to the well, following the activity described in subdivision (2), and circulated until a chlorine concentration of not less than fifty (50) mg/l in the entire volume of fluid is achieved.(c) Immediately before placement in the void caused by settled gravel in a well, replacement gravel shall be soaked in a chlorine solution of at least fifty (50) mg/l for a duration not less than thirty (30) minutes during initial construction or subsequent repairs.(d) Permanent equipment and material used in a production well shall be chlorinated before installation by spraying exposed areas with a solution containing a chlorine residual of not less than two hundred (200) mg/l.(e) A new or modified well proposed to be a production well shall be chlorinated in accordance with one (1) of the following:(1) The water in the well casing shall be treated for disinfection as follows: (A) To create a chlorine residual of one hundred (100) mg/l to the entire volume of water in the casing, well screen, and rock hole, if present.(B) The well must be:(i) chlorinated using the compound requirements in Table 24-1; and(ii) surged at least three (3) times following chlorination.(C) The chlorinated water must remain in the well casing at least twelve (12) hours following the surging activity of clause (B)(ii).(2) The water in the well casing shall be treated for disinfection as follows: (A) To create a chlorine residual of fifty (50) mg/l to the entire volume of water in the casing, well screen, and rock hole, if present.(B) The well must be:(i) chlorinated using the compound requirements in Table 24-1; and(ii) surged at least three (3) times following chlorination.(C) The chlorinated water must then remain in the well casing at least twenty-four (24) hours following the surging activity of clause (B)(ii). The following table demonstrates the amount of chemical compound needed for chlorination of wells:
Table 24-1 Amount of Chemical Compound Needed for Chlorination of Wells
| Well-Hole or Well-Casing Diameter (in.) | Volume per 100 Feet of Water Depth (gal) | Calcium Hypochlorite* (65 percent available Cl2) | Sodium Hypochlorite[DRAGGER] (12 trade percent[DRAGGER]) |
| 5 | 106.09 | 1.1 oz | 5.65 fl oz |
| 6 | 146.9 | 1.5 oz | 7.8 fl oz |
| 8 | 261.1 | 2.7 oz | 13.9 fl oz |
| 10 | 408.0 | 4.2 oz | 1.4 pt |
| 12 | 587.5 | 6.0 oz | 2.0 pt |
| 16 | 1,044.0 | 10.7 oz | 3.5 pt |
| 20 | 1,632.0 | 1 lb 1 oz | 0.7 gal |
| 24 | 2,350.0 | 1 lb 8 oz | 1.0 gal |
| 30 | 3,672.0 | 2 lb 6 oz | 1.5 gal |
| 36 | 5,287.0 | 3 lb 6 oz | 2.2 gal |
| 48 | 9,400.0 | 6 lb 1 oz | 3.9 gal |
| 60 | 11,690.0 | 9 lb 7 oz | 6.1 gal |
Notes:
*Quantities of Ca (OCl)2 based on 65 percent available chlorine by dry weight (16 oz = 1 lb).
[DRAGGER]Quantities of NaOCl based on 12 trade percent available chlorine by U.S. liquid measure (1 gal = 4 qt = 8 pt = 128 fl oz).
[DRAGGER]Trade percent is a term used by chlorine manufacturers; trade percent × 10 = grams of available chlorine in 1 liter of solution.
(f) After disinfection accomplished in accordance with subsection (e), a new or modified public water system production well and a flowing well shall be sampled for the presence of coliform at least twice, with sampling done not less than twenty-four (24) hours apart, by a laborat+ory certified by the Indiana state department of health or the United States Environmental Protection Agency using methods specified in 327 IAC 8-2-8.7. If the presence of coliform is indicated by the sample results, the disinfection of the well shall be repeated.(g) Disposal of chlorinated water from well disinfection shall be to one (1) of the following sources: (1) A sanitary sewer with the approval of the local sewer authority.(2) A location other than a sanitary sewer in accordance with local, state, and federal regulations.Water Pollution Control Board; 327 IAC 8-3.4-24; filed Jun 17, 1999, 1:50 p.m.: 22 IR 3377; readopted filed Jan 10, 2001, 3:23 p.m.: 24 IR 1518; filed Apr 24, 2006, 3:00 p.m.: 29 IR 2969; readopted filed Nov 21, 2007, 1:16 p.m.: 20071219-IR-327070553BFA; readopted filed Jul 29, 2013, 9:21 a.m.: 20130828-IR-327130176BFAReadopted filed Jun 6, 2019, 1:59 p.m.: 20190710-IR-327190246BFA