1. (a) Except as specified in (c), below, no component of a stormwater management system shall discharge stormwater directly to groundwater or to the ground surface in an area where the stormwater will infiltrate the groundwater within a sanitary protective area for a water supply well as specified in:

   1. (1) For any large production well and any well for a large community water system, the larger of the sanitary protective radius established under Env-Dw 302.10, or the approval issued under Env-Dw 302;
   2. (2) For any small production well for a small community water system, the larger of the sanitary protective radius established under Env-Dw 305.10, or the approval issued under Env-Dw 305;
   3. (3) For any non-community water system, the applicable distance from Env-Dw 406.14; or
   4. (4) Table 1008-4 in Env-Wq 1008.06, for private water supply wells, whether commercial or non-commercial.
2. (b) Within a water supply intake protection area, a stormwater management system shall not discharge to the surface water that defines the protection area, or to the ground surface, subsurface, or groundwater within 100 feet of that surface water, except as specified in (c), below.
3. (c) Stormwater management systems that discharge stormwater from areas less than 0.5 acre and that do not and will not receive stormwater from a high-load area shall be exempt from the private well and surface water setbacks of (a) and (b), above, provided that no component of the stormwater management system is located within 50 feet of a well and flow is directed away from the well.
4. (d) A stormwater management system that discharges within a water supply intake protection area or to a storm sewer system that discharges within a water supply intake protection area shall incorporate water-tight designs that allow for shut-down or containment in the event of a spill if the system serves a bulk plant or terminal where bulk petroleum products or hazardous materials are transferred.

Source. #9343, eff 1-1-09; ss by #12342, eff 8-15-17; ss by #14472, eff 1-19-26, EXPIRES: 1-19-36