SECTION 252:641-12-7. Spray irrigation fields

(a)   Location. All spray irrigation fields shall:

(1)   be preceded by an aerobic treatment unit;

(2)   be located in the identified dispersal site, when a soil profile test is used to size the irrigation field;

(3)   utilize at least two sprinkler heads to disperse the treated effluent; and

(4)   be vegetated and landscaped, and/or terraced to prevent runoff.

(b)   Sizing. The spray irrigation field shall be sized according to Appendix H, Figures 13-22. When calculating the overall area of the spray irrigation field, areas of overlap may only be counted once.

(c)   Sprinklers. The sprinklers shall be designed to:

(1)   provide uniform distribution of treated effluent over the entire spray irrigation field without misting; and

(2)   have a trajectory of no more than fifteen-degrees (15°) to keep the spray stream low to the ground surface.

(d)   Spray irrigation. The spray irrigation shall be:

(1)   adjusted and maintained at a rate to prevent runoff; and

(2)   controlled by a timing device to take place daily between 1:00 a.m. and 6:00 a.m.

[Source: Added at 25 Ok Reg 2318, eff 7-11-08; Amended at 37 Ok Reg 1296, eff 9-15-20]