La. Admin. Code tit. 51 § XIII-733

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

Section XIII-733 - Effluent Reduction Options [formerly Section IX of Appendix A]

A. [Formerly paragraph A:9.8-1 of Appendix A] Effluent Reduction Field. This system is installed downstream of a mechanical treatment plant or other sewage treatment system listed in Chapter 7 Subchapter B of this Code that produces an effluent, but does not by design significantly reduce that effluent. The effluent reduction field is essentially a soil absorption field as described in §719 of this Subchapter, but with modification as noted in this Section. Section 1501. B 13 (Figure 15) has a diagram with specifications and cross-sections of the effluent reduction field.

1. [Formerly paragraph A:9.8-2 of Appendix A] If there is not sufficient grade to install the sewerage system and the effluent reduction field with gravity flow to the discharge point, then a pump station in compliance with applicable provision of this code must be installed.

2. [Formerly paragraph A:9.8-3 of Appendix A] The force of the pumped effluent must be reduced by use of a distribution box, "Tee," or similar appurtenance.

3. [Formerly paragraph A:9.8-4 of Appendix A] The effluent reduction field trenches shall be at least 18 inches wide and between 16 to 24 inches in depth.

4. [Formerly paragraph A:9.8-5 of Appendix A] The bottom of the effluent reduction field must be level.

5. [Formerly paragraph A:9.8-6 of Appendix A] The fill or cover material shall be of porous soil or sand which allows the passage of water in all directions, with sod started on top. Fill should be at least 4 to 6 inches above grade and spread at least 3 to 4 feet on either side of the trench.

6. [Formerly paragraph A:9.8-7 of Appendix A] The effluent reduction field (ERF) must be installed a minimum of 10 feet from any property line. In addition the ERF field location shall comply with the minimum distance requirements from water wells and suction lines, water pressure lines, etc., as contained in Parts XII and XIV of this Code.

7. [Formerly paragraph A:9.8-8 of Appendix A] The minimum length of the effluent reduction field shall be determined by the treatment capacity of the sewerage system.

Treatment Capacity of Sewerage System	Minimum Total Length per Field
500 GPD or less	100 ft
501-750 GPD	150 ft
751-1000 GPD	200 ft
1001-1500 GPD	300 ft

8. [Formerly paragraph A:9.8-9 of Appendix A] If more than one absorption trench is used to provide the minimum required length of the effluent reduction field, the distance between individual trenches must be at least 6 feet with one discharge pipe provided.

9. [Formerly paragraph A:9.8-10 of Appendix A] The pipe from the end of the effluent reduction field to the discharge point must be solid.

10. [Formerly paragraph A:9.8-11 of Appendix A] A backwater valve must be provided at the end of the effluent reduction field whenever the discharge line is less than 12 inches above the ditch flow-line.

11. [Formerly paragraph A:9.8-12 of Appendix A] Each individual trench must not be greater than 100 feet in length. Clam or oyster shells may be substituted for gravel in the effluent reduction field. If used, gravel must be clean, graded and 1/2-inch to 2 1/2 inches in diameter. Other media may be considered for use if determined to have acceptable characteristics and properties. Although it may not be noted in the attached figures (§1501. B 1-19), the end of the discharge line must have a 1/2 diameter PVC end cap over the lower half of the endpipe, causing longer retention of the effluent and providing greater opportunity for absorption. If the end of the discharge line is more than 2 inches lower than the absorption line, other provisions must be made to cause the effluent to be retained in the reduction field.

12. [Formerly paragraph A:9.8-13 of Appendix A] Gravelless pipe or other distribution chambers may be used in lieu of conventional soil absorption pipe. If gravelless pipe is used, the fill must be porous soil or sand which allows the passage of water in all directions, with a 6-inch layer below the pipe and filled 4 to 6 inches above grade and spread 3 to 4 feet on either side of the trench.

B. [Formerly A:9.9-1 of Appendix A] Rock-Plant Filter. All rock plant filters must be a minimum of 5 feet wide to a maximum of 10 feet wide.

1. [Formerly paragraph A:9.9-2 of Appendix A] The square footage will be determined by the treatment capacity of the sewerage system as follows.

Treatment Capacity of Sewerage System	Rock Plant Filter Size
500 GPD or less	150 square feet
501-750 GPD	225 square feet
751-1000 GPD	300 square feet
1001-1500 GPD	450 square feet

a. Refer to §1501. B 14 (Figures 16 and 17) for a schematic and cross section of a rock plant filter with a sewerage system installation.

2. [Formerly paragraph A:9.9-3 of Appendix A] The rock plant filter (RPF) must be installed a minimum of 10 feet from any property line. In addition, the RPF location shall comply with the minimum distance requirements from water wells and suction lines, water pressure lines, etc., as contained in Parts XII and XIV of this Code.

3. [Formerly paragraph A:9.9-4 of Appendix A] If there is not sufficient grade to install the sewerage system and the rock plant filter with gravity flow to the discharge point, then a pumping station in compliance with applicable provisions of this Part must be installed.

4. [Formerly paragraph A:9.9-5 of Appendix A] In order to prevent backflow, a backwater valve is required whenever the discharge line is less than 12 inches above the ditch flow-line.

5. [Formerly paragraph A:9.9-6 of Appendix A] Only a standard shape bed may be installed with a minimum width of 5 feet and of such length as to provide the required square footage.

6. [Formerly paragraph A:9.9-7 of Appendix A] Plans for any other configuration must be submitted for review and approval to the sanitarian regional director.

7. [Formerly paragraph A:9.9-8 of Appendix A] A liner will be required when the ground water level is within 24 inches of the bottom of the trench.

8. [Formerly paragraph A:9.9-9 of Appendix A] The polyethylene liner may be of more than one layer provided a total thickness of 16 mil is achieved.

9. [Formerly paragraph A:9.9-10 of Appendix A] When a liner is not required, the use of landscape fabric is highly recommended to prevent weed intrusion.

10. [Formerly paragraph A:9.9-11 of Appendix A] The bottom of the bed must be level and be no deeper than 14 inches.

11. [Formerly paragraph A:9.9-12 of Appendix A] A depth of approximately 10 to 12 inches is best.

12. [Formerly paragraph A:9.9-13 of Appendix A] Gravel must be 2-3 inches in diameter and laid to a depth of 12 inches.

13. [Formerly paragraph A:9.9-14 of Appendix A] An 8-inch water level must be maintained. Gravel should fill the filter bed to above surface grade to prevent erosion.

14. [Formerly paragraph A:9.9-15 of Appendix A] The minimum 4-inch perforated inlet pipe must be located no closer than 4 inches from the bottom of the bed and supported by a footing of noncorrosive material, such as concrete or treated timber.

15. [Formerly paragraph A:9.9-16 of Appendix A] The inlet should extend no more than 2 feet into the rock plant bed and must be provided with a "Tee" (with ends capped) extending the width of the bed to within 1 foot of the side walls.

16. [Formerly paragraph A:9.9-17 of Appendix A] The outlet pipe shall also be set in a footing of noncorrosive material (concrete or treated timber) on the bottom of the bed with the same "Tee" and configuration. The outlet must be elbowed up and out [§1501. B 14 (Figure 17)].

17. [Formerly paragraph A:9.9-18 of Appendix A] Do not allow plants to grow within 3 feet of the inlet and outlet of the bed.

18. [Formerly paragraph A:9.9-19 of Appendix A] A levee support system around the perimeter of the filter should be constructed to exclude surface water. The use of landscape timbers for this purpose is acceptable. Other materials, such as concrete, can also be used.

C. [Formerly paragraph A:9.10-1 of Appendix A] Spray Irrigation. The spray irrigation system [§1501. B 15 (Figure 18)] uses an electric pump that distributes the effluent to the yard through sprinkler heads. It is highly recommended for spray irrigation effluent to be chlorinated in a contact chamber, sized according to §731 A, following the treatment unit and preceding discharge. At a predetermined level, a float switch activates a pump that forces the effluent through piping to pop-up or elevated rotating type sprinkler heads. Evaporation and soil infiltration of the dispersed effluent should prevent any run-off from occurring.

1. [Formerly paragraph A:9.10-2 of Appendix A] A pump station system must be sized according to use and comply with the applicable provisions of this Part.

2. [Formerly paragraph A:9.10-3 of Appendix A] The pressure pump must be a minimum of one-half horse power capable of producing a minimum flow of 12 gallons per minute and maintaining 25 pounds per square inch at all sprinkler heads.

3. [Formerly paragraph A:9.10-4 of Appendix A] The pump will be activated by a high/low water switch through an automatic on/off switch. The pump must be deactivated through a low-volume cut off switch.

4. [Formerly paragraph A:9.10-5 of Appendix A] A time cycle device may be used to allow for specific sprinkling times (e.g., nighttime, afternoon). The pump chamber must be of adequate liquid capacity to allow sufficient storage to accommodate the desired time settings.

5. [Formerly paragraph A:9.10-6 of Appendix A] A minimum of three 4-inch type sprinkler heads coded for wastewater effluent, spaced a minimum of 40 feet apart are required.

6. [Formerly paragraph A:9.10-7 of Appendix A] The spray irrigation sprinklers shall comply with American Society of Agricultural Engineers (ASAE) Standard S 398.1 (Procedure for Sprinkler Testing and Performance Reporting).

7. [Formerly paragraph A:9.10-8 of Appendix A] The slope of the land shall be such as to facilitate drainage away from any water well or well suction lines. The edge of the spray and its drainage must be a minimum of 50 feet from any private water well and its associated suction lines and 10 feet from any property line. The edge of the spray and its drainage shall be a minimum 100 foot from public any water supply well and its associated suction lines, if any. In addition, the edge of the spray and its drainage shall be a minimum of 25 feet from any potable water (pressure) lines. As contained in Parts XII and XIV of this Code.

8. [Formerly paragraph A:9.10-9 of Appendix A] Exceptions due to lot size, topography or other constraints may be authorized by the sanitarian parish manager with written notification of such authorization to the sanitarian regional director and a copy attached to the LHS-47.

D. [Formerly paragraph A:9.11-1 of Appendix A] Overland Flow. When the size of the property is 3 acres or more, an overland flow may be utilized [§1501. B 16 (Figure 19)].

1. [Formerly A:9.11-2 of Appendix A] The discharge through perforated pipe must be distributed in such a manner as to confine the effluent on the property owned by the generator.

2. [Formerly A:9.11-3 of Appendix A] The location of the overland discharge must have a permanent vegetative cover.

3. [Formerly A:9.11-4 of Appendix A] The slope of the land shall be such as to facilitate drainage away from any water well or well suction lines. The discharge point and the field of flow shall be a minimum of 50 feet from any private water well and its associated suction lines. The discharge point and the field of flow shall be a minimum 100 foot from public water supply wells and its associated suction lines, if any. In addition, the discharge point and the field of flow shall be a minimum of 25 feet from any potable water (pressure) lines. As contained in Parts XII and XIV of this Code.

4. [Formerly A:9.11-5 of Appendix A] A header should be used at the end of the discharge line to help disperse the effluent and to discourage channelization. The point of discharge must be such that there is at least a 200 foot flow of effluent over the property of the generator.

5. [Formerly A:9.11-6 of Appendix A] Construction of the system should be such that it is not closer than 20 feet from the property line.

E. [Formerly A:9.12 of Appendix A] Mound System or Subsurface Drip Disposal [§1501. B 17 and 18 (Figures 20 and 21)]. Either can be considered by DHH-OPH on a case to case basis. Plans and specifications must be submitted to DHH-OPH engineering services in consultation with the sanitarian regional director for review and approval prior to construction.

La. Admin. Code tit. 51, § XIII-733

Promulgated by the Department of Health and Hospitals, Office of Public Health, LR 28:1357 (June 2002).

AUTHORITY NOTE: Promulgated in accordance with R.S. 40:4(A)(6) and R.S. 40:5(9)(20).