R 323.2231 Certain treatment systems; design, operation, maintenance, limitation, and monitoring.

Rule 2231. (1) A treatment system described in R 323.2216(3) that involves lagoon storage and land treatment shall be designed, operated, maintained, limited, and monitored in accordance with all of the following provisions: (a) The lagoon liner shall meet the requirements of R 323.2237. (b) The minimum storage volume of the lagoon system shall be 1/2 of the annual influent flow. (c) The lagoon system shall be a minimum of 2 cells as follows: (i) Cell 1 shall not exceed a maximum depth of 6 feet. (ii) Cell 2 shall not exceed a maximum depth of 8 feet. (iii) Subsequent cells shall not exceed a maximum depth of 10 feet. (d) A lagoon system that has mechanical aerators shall meet all of the following criteria: (i) The lagoon system shall be a minimum of 2 cells. (ii) A minimum of 2 mg/l dissolved oxygen shall be maintained in the primary cell. (iii) The maximum depth of secondary cells shall not exceed 10 feet. (e) A lagoon shall have security fencing and warning signs. (f) Wastewater disposal shall be by means of land application to a suitable crop in accordance with R 323.2233. (g) Effluent may be discharged from May 1 through October 15, unless alternative dates are approved by the department. (h) A discharge shall occur only from an isolated cell. An isolated cell is one that has not received untreated wastewater at least 30 calendar days before a discharge. (i) A discharger shall inspect the lagoon facilities weekly and maintain an inspection log unless otherwise authorized by the department. (j) A discharger shall meet all of the following requirements when drawing down a cell for transfer or discharge unless otherwise authorized by the department: (i) Water discharged or transferred shall be removed from the surface 2 feet of the cell at a rate of less than 1 foot per day. (ii) A discharger shall maintain a minimum of 2 feet of freeboard in all cells at all times. (iii) A discharger shall maintain a minimum of 2 feet of water in all cells at all times. (k) A discharger shall implement a facility maintenance program that, at a minimum, incorporates all of the following management practices unless otherwise authorized by the department: (i) Vegetation shall be maintained at a height not more than 6 inches above the ground on lagoon dikes. (ii) Not more than 10% of the water surface shall be covered by floating vegetation and not more than 10% of the water perimeter may have emergent rooted aquatic plants. (iii) Dikes shall be inspected for evidence of erosion and animal burrowing. Damage due to erosion or animal burrowing shall be corrected immediately and steps taken to prevent occurrences in the future. (iv) The occurrence of any of the following shall be minimized and immediate steps shall be taken to eliminate each occurrence: (A) Scum. (B) Floating sludge. (C) Offensive odors. (D) Insect infestations. (E) Septic conditions. (2) A treatment system which is described in R 323.2116(3) and which does not involve land treatment, such as a sequencing batch reactor, oxidation ditch, or activated sludge with denitrification capabilities, shall meet the following requirements, as applicable: (a) A system that does not have a minimum storage volume of 1/2 the annual influent flow shall comply with both of the following provisions: (i) Meet the requirements of R 323.2222 in the effluent. (ii) Have a contingency plan to deal with periods of upset, mechanical malfunctions, and routine maintenance while maintaining compliance with this part. (b) A sequencing batch reactor system shall have a minimum of 2 treatment tanks.