Michigan Administrative Code › Department - Environmental Quality › Water Resources Division › Water Resources Protection › Part 22 - GROUNDWATER QUALITY › Section R. 323.2231 - Certain treatment systems; design, operation, maintenance, limitation, and monitoring

Current through Vol. 24-12, July 15, 2024
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.