La. Admin. Code tit. 51 § XII-267

Current through Register Vol. 50, No. 11, November 20, 2024

Section XII-267 - "Red Water" Waste

A. Waste filter wash water from iron and manganese removal plants shall be properly disposed of in accordance with one of the following methods:

1. Sand Filters. The sand filters should have the following features:

a. Total filter area shall be sufficient to adequately dewater applied solids. Unless the filter is small enough to be cleaned and returned to service in 1 day, two or more cells are required.

b. The "red water" filter shall have sufficient capacity to contain, above the level of the sand, the entire volume of wash water produced by washing all of the production filters in the plant, unless the production filters are washed on a rotating schedule and the flow through the production filters is regulated by true rate of flow controllers. Then sufficient volume shall be provided to properly dispose of the wash water involved.

c. Sufficient filter surface area should be provided so that, during any one filtration cycle, no more than 2 feet of backwash water will accumulate over the sand surface.

d. The filter shall not be subject to flooding by surface runoff or flood waters. Finished grade elevation shall be established to facilitate maintenance, cleaning and removal of surface sand as required. Flash boards or other non-watertight devices shall not be used in the construction of filter side walls.

e. The filter media should consist of a minimum of 12 inches of sand, 3 to 4 inches of supporting small gravel or torpedo sand, and 9 inches of gravel in graded layers. All sand and gravel should be washed to remove fines.

f. Filter sand should have an effective size of 0.3 to 0.5 mm and a uniformity coefficient not to exceed 3.5. The use of larger sized sands shall be justified by the designing engineer to the satisfaction of the state health officer.

g. The filter should be provided with an adequate under-drainage collection system to permit satisfactory discharge of filtrate.

h. Provision shall be made for the sampling of the filter effluent.

i. Overflow devices from "red water" filters shall not be permitted.

j. Where freezing is a problem, provisions should be made for freeze protection for the filters during the winter months.

k. "Red water" filters shall comply with the common wall provisions contained in §177 of this Part, which pertain to the possibility of contaminating treated water with unsafe water.

l. The state health officer shall be contacted for approval of any arrangement wherein a separate structure is not provided.

2. Lagoons. The lagoons shall have the following features:

a. be designed with a volume 10 times the total quantity of wash water discharged during any 24-hour period;

b. have a minimum usable depth of 3 feet;

c. have a length 4 times width, and the width at least 3 times the depth, as measured at the operating water level;

d. be designed such that the outlet is located at the end opposite the inlet;

e. have a weir overflow device at the outlet end with weir length equal to or greater than depth;

f. have provisions for the velocity to be dissipated at the inlet end; and

g. subsurface infiltration lagoons shall be acceptable only if approved by the appropriate reviewing authority/authorities.

3. Red water can be discharged to a community sewer. Approval of this method will depend on obtaining approval from the owner of the sewerage system as well as from the state health officer before final designs are made.

a. A surge tank is recommended to prevent overloading of the sewers.

b. Design shall prevent cross connections.

c. There shall be no common walls between potable and non-potable water compartments.

4. Red water may be discharged into surface water. However, the plant must have an NPDES (National Pollutant Discharge Elimination System) permit or other applicable discharge permit from the appropriate regulatory authority/authorities to dispose of backwash water into surface water.

5. Recycling of supernatant or filtrate from "red water" waste treatment facilities to the head end of an iron removal plant shall not be allowed except as approved by the state health officer.

La. Admin. Code tit. 51, § XII-267

Promulgated by the Department of Health, Office of Public Health, LR 44343 (2/1/2018), effective 8/1/2018.

AUTHORITY NOTE: Promulgated in accordance with the provisions of R.S. 40:4.A.(8), 40:4.13.D.(1)(2) and 40:5.A.(2)(3)(5)(6)(7)(17).