Arkansas Administrative Code
Agency 007 - Arkansas Department of Health
Division 04 - Environmental Health Services
Rule 007.04.21-001 - Rules Pertaining to Drip Dispersal Systems

Universal Citation: AR Admin Rules 007.04.21-001

Current through Register Vol. 49, No. 9, September, 2024

SECTION 1. Authority and Purpose

1.1 The following RULES PERTAINING TO DRIP DISPERSAL SYSTEMS are duly adopted and promulgated by the Arkansas State Board of Health pursuant to the authority expressly conferred by the laws of the State of Arkansas including, without limitation. Act 96 of 1913 (A.C.A. (20-7-109), and Act 402 of 1977 (A.C.A. (14-236-101) et. seq.)

1.2 Purpose: A drip dispersal system is a technology for the distribution of treated wastewater uniformly over a large area beneath the soil surface. Drip Dispersal fields are a "bed" design. The use of four (4) to six (6) inch installation cover does not fit the conventional trench design criteria utilized in the Onsite Wastewater Soil Morphology Program for system design.

SECTION 2. Definitions

2.1 Aerobic Treatment Unit (ATU): A mechanical on-site treatment unit that provides secondary wastewater treatment by mixing air and aerobic and facultative microbes with the wastewater. ATU's typically use a suspended growth treatment process or a fixed treatment process.

2.2 Air/Vacuum (A/V) Relief Valve: A valve that automatically lets air out of or into liquid carrying pipe as needed in response to changes in system pressure.

2.3 Aerobic: Having molecular oxygen as a part of the environment, or growing or occurring only in the presence of molecular oxygen.

2.4 Backwash: The process of flow reversal to clean a filter and to restore it to the normal clean condition for filtering with a minimum resistance to flow through the media or screen.

2.5 Control Panel: An electronic control panel that controls the quantity and time of dose. This can also control the zone receiving the effluent, automatically flushes the lines, flushes the filters, monitors the flow rates and pump run cycles or times.

2.6 Decentralized System: An onsite and/or cluster wastewater system used to treat and disperse or discharge small volumes of wastewater, generally from dwellings or businesses that are located relatively close together.

2.7 Disk Filter: A type of filter that utilizes a series of grooved rings that overlay each other to form a network of very small openings to trap contaminants.

2.8 Distributing Valve: A valve that distributes flow to multiple drain field laterals, zones or locations by automatically rotating upon each pump cycle.

2.9 Drain-back: The process of effluent draining along the laterals and manifolds after the pump shuts off. Drainage occurs both inside and outside the drip tubing and manifolds to lower elevations in the drip field.

2.10 Drip Line: Tubing constructed from polyethylene with emitters embedded regularly along the length of the tube.

2.11 Effluent: Sewage, water or other liquids, partially or completely treated or in its natural state flowing out of a septic tank, aerobic treatment unit, or other treatment system or systems.

2.12 Emitters: Small diameter openings in drip line that can dissipate pressure and allow a slow, controlled discharge normally rated in gallons per hour.

2.13 Field Flush: Water is passed through the drip lateral for the purpose of removing particles and other debris from the walls of the drip tubing. The flush water is carried back through the return manifold and return line to the pretreatment unit.

2.14 Filter: A device for the main purpose of removing suspended solids and other debris from the wastewater.

2.15 Hydraulic Conductivity: The rate of water movement under unit gradient in a specific soil horizon.

2.16 Interceptor Drain: A subsurface drain line, usually constructed upgrade from the absorption area to divert seasonal groundwater.

2.17 Lateral: One single run or multiple runs of drip tubing connected at one end to a supply manifold and the other end connected to a return manifold.

2.18 Maintenance Personnel: A individual certified by the Department to conduct assessments under the Onsite Maintenance and Monitoring Program.

2.19 Monitoring: Periodic inspection of system for performance.

2.20 Pressure Compensating (PC) Emitters: Drip emitters that allow a constant flow or discharge over a wide range of applied pressure.

2.21 Pressure Distribution: A system of small diameter pipes equally distributing effluent through a trench or bed.

2.22 Pressure Regulator: A device used to regulate and maintain a constant discharge pressure.

2.23 Pretreatment: The conditioning of effluent prior to dispersal by a drip system.

2.24 Return Line: The return line connects the return manifold to the pretreatment unit for the purpose of carrying flush water from the drip field.

2.25 Return Manifold: A collection manifold or piping that returns excessive wastewater and debris to the primary treatment tank during system flushes.

2.26 Run: One continuous length of tubing routed across contour connected to a supply line or return line or another run.

2.27 Soil Structure: The combination or arrangement of individual soil particles in definable aggregates, or peds, which are characterized and classified on the basis of size, shape, and degree of distinctness.

2.28 Solenoid Valve: An electric valve actuated by a solenoid, used for controlling the flow or liquid in pipes.

2.29 Spin Filter: A filter that consist of a screen cylinder enclose in a casing. The typical filter screen mesh size is 150 and a micron rating of 100.

2.30 Static Plow: A drip line plow with a shank that remains at a given depth as the plow is pulled through the soil.

2.31 Supply Line: The line that extends from the pump to the supply manifold of a given zone.

2.32 Supply Manifold: The supply manifold connects the supply line to the drip laterals.

2.33 Vertical Separation: The depth of unsaturated, original, undisturbed soil between the bottom of the drip tubing and highest seasonal water table or restrictive layer.

2.34 Vibratory Plow: A vibratory plow is a drip line plow with a shank that vibrates vertically as the plow is pulled through the soil.

2.35 Water Table: The level in saturated soil at which the hydraulic pressure is zero.

2.36 Zone: A group of laterals that are dosed at the same time.

SECTION 3. Site Assessment

3.1 Subsurface Drip System(s) may be utilized on sites that meet the following criteria:
3.1.1 The drip tubing or installed trench bottom shall be above the seasonal water table, whatever the duration. Brief seasonal water tables may be minimized or eliminated by the use of effective interceptor drains. Any design, which incorporates the use of an interceptor drain, shall indicate the effective depth of seasonal water table reduction.

3.1.2 Low hydraulic conductivity shall include soils with 40% or greater clay. Clay percentage shall be determined from in depth zone extending 6" above and 12" below installed drip tubing depth.

3.1.3 No loading rates are available for low hydraulic conductivity soils with greater than 60% clay.

3.1.4 Systems utilizing drip dispersal must maintain minimum of 9" separation between drip tubing and any rock substrata (consolidated or fractured) for soils that exhibit a moderate and/or long SWT.

3.1.5 Systems utilizing drip dispersal must maintain minimum of 15" separation between drip tubing and any rock substrata (consolidated or fractured) for soils that exhibit only a brief SWT or do not exhibit a SWT.

3.1.6 Soils that are structure less or with massive structure shall not be approved for onsite sub-surface treatment.

3.1.7 The lot size shall be of sufficient area to accommodate both the primary and secondary dispersal area.Both the primary and secondary dispersal area shall be sized according to the respective loading rates. If the lot can only support the primary dispersal field, a subsurface drip dispersal system shall not be installed.

SECTION 4. Drip Tubing and Emitters

4.1 Emitter spacing can range from six (6) to twenty-four (24) inches. The emitters used in the tubing shall be pressure compensating. Pressure compensating emitters have a relatively constant discharge rate over a wide range of pressures. Emitter flow rate shall be specified by the designer and stated on the system plans. The drip line pressure can range from 5 to 70 pounds per square inch (PSI).

4.2 Drip tubing shall be installed by one of the following methods; static plow, chain trencher or vibratory plow.

4.3 Static plow is the preferred method for inserting drip tubing into the soil. The static plow shall be pulled not pushed through the soil.

4.4 Chain trencher may be used for placement of the drip tubing in the soil. The maximum chain trench width is four (4) inches.

4.5 Wet soil shall not be plowed because of smearing.

4.6 Drip tubing installed in natural soil shall be installed to a depth of six (6) inches.

4.7 If capping fill material is used as part or all of the cover over the tubing, the installed depth of the tubing can range from one (1) to five (5) inches in the natural soil. Drip tubing shall not be placed in the capping fill material. In no case shall the cover over the tubing be less than six (6) inches.

4.8 Settled depth of the cap shall not be more than eight (8) inches. The capping fill material shall not contain more than 27% clay or 60% sand or 70% silt. Before the capping fill material is delivered to the proposed dispersal site, a textural analysis shall be provided. A credit of up to 50% of the settled cap depth may be allowed in the adjustment of the seasonal water table. The seasonal water table credit is at the sole discretion of the Department.

SECTION 5. Pretreatment Requirements

5.1 The quality of effluent that will be applied to the dispersal field shall meet the Ameriean National Standards Institute/National Sanitation Foundation (ANSI/NSF) Standard 40 (revised 2005) requirements for elass 1 treatment systems. Only pretreatment units that have obtained approval from the Department shall be used.

5.2 Pretreatment system shall be required as part of any Drip Dispersal System design.

5.3 The daily flow rate capaeity of a pretreatment system shall equal or exceed the daily flow rates found in Appendix B of the Rules and Regulations Pertaining to Onsite Wastewater Systems.

5.4 Pretreatment systems installed in conjunction with an individual residential structure shall have a daily flow rate capacity of not less than 400 gallon per day.

5.5 Pretreatment systems installation on non-residential or multi-structures shall be sized according to influent wastewater strength and total daily flow rate expressed in gallons per day.

SECTION 6. Filters and Screens

6.1 There are three types of filters or screens used for wastewater applications: spin or screen filter, disk, and sand.

6.2 Solids and other debris shall be filtered to a size of 100 microns or less.

6.3 Filter debris shall be returned to the septic tank, pretreatment unit, or a separate settling tank regardless of the type of filter system. The clear Schedule 40 PVC piping allows for a direct observation of the wastewater as it flows from the filter flush line or the field flush line.

SECTION 7. Control Panel

7.1 Timed dosing is the only method for controlling the dose cycles and volumes.

7.2 Control panels shall be constructed of the following basic components; NEMA 4X rated enclosure, motor-start contractors, separate circuit breakers for pump and panel control, audio and visual alarms, and wiring terminals. Optional components range from elapsed time meter or counters, event counters and pump run lights.

SECTION 8. Flow Meters and Pressure Gauges

8.1 A flow meter shall be installed after the filter system but before the drip dispersal field. The flow meter shall incorporate not only a rate of flow gauge but also a total gallons pumped register. The flow rate gauge and total gallons pumped register may be separate devices. The flow meter shall be installed in a protective box that will be of sufficient size for servicing the meter and to allow easy access for reading the meter. The flow meter shall be sized for the dispersal flow as well as the additional field flushing volume.

8.2 Pressure gauges shall be located before the filter, after the filter and on the dispersal field return line. Pressure gauges shall be enclosed in the head works box, which allows easy access for observation. The gauges shall be liquid filled and a minimum of three (3) inches in diameter. The pressure range of the gauge shall be sufficient for the maximum pressure that will be expected in the system.

SECTION 9. Supply Line and Manifold

9.1 The supply line and manifold should be designed with a flow velocity between the 0.5 feet per and 5 feet per second.

9.2 The piping and fittings in the supply line and the manifold shall be Schedule 40. Schedule 80 fittings shall be used at the filter system as well as any point where the piping will be discormected or subjected to abuse.

9.3 When dosing, the supply manifold shall eliminate the drain back potential from a higher to a lower elevation in the drain field.

SECTION 10. Return Manifold and Line

10.1 The return manifold and line allow the flushing of the drip dispersal field. The flushed wastewater and solids shall be returned back to the settling tank or treatment tank.

SECTION 11. Flexible Hose and Tubing

11.1 Flexible Schedule 40 PVC piping shall be used at all connections to the supply and return manifolds.

SECTION 12. Air/Vacuum Relief Valves

12.1 Air/vacuum relief valves provide a means for releasing air at the start of a dose cycle, so the system will charge quickly with wastewater and allow air to enter the system quickly at the end of dose cycle. Air/vacuum valves shall be located at the highest points of either supply or return manifolds, or both.

12.2 Air/vacuum relief valves shall be sized based on the proposed design flow rate. A valve that is under sized will not provide an adequate amount of airflow.

12.3 A Schrader valve shall be provided at each vacuum valve as a means of checking the pressure of the drip field.

SECTION 13. Flushing Valves

13.1 Automatic flushing controls shall be required for all drip systems. The flush valve shall be a solenoid or a pressure/flow compensating valve. Manual flushing valves may be installed in the field flush line. Manually operated valves may be standard ball or gate valves. The flush valve shall be fully opened during a flush cycle, regardless of the valve type. The field flushing velocity shall be in accordance with the drip tubing or system manufacturer's recommendations. The minimum field flushing velocity shall not be less than 0.5 feet per second.

SECTION 14. Pipe and Specialty Connectors and Fittings Standard

14.1 PVC pipe, tubing, reducer tees, adapters, elbows, couplers and compression fittings shall be constructed of Schedule 40 PVC.

14.2 Lock-Slip fittings, adapters, tees, elbows, and couplings shall be specifically manufactured for use with wastewater drip dispersal systems.

14.3 Insert fittings, barbed adapters, tees, elbows, and couplings shall be specifically manufactured and sized for use with wastewater drip dispersal system.

SECTION 15. Headworks Boxes

15.1 Any component or assembly that may need to be routinely serviced shall be located in a headworks box that is readily accessible.

15.2 Headworks boxes may be constructed of high-density PE (polyethylene) fiberglass, PVC, or concrete.

15.3 Headworks boxes shall be large enough to allow ease of service and allow periodic removal and replacement of components as needed. The headworks box shall be of sufficient length and depth to accommodate the various components that will be housed in the box. The lid of the headworks box shall extend above the finished grade. The bottom of the headworks box shall be designed to drain any rainwater or wastewater away from the inside of the box. The headworks box lid shall be easy to remove but also shall be made tamperproof where access to the site is not restricted or controlled. The structural strength of the headworks box and lid shall be sufficient to withstand the weight of any lawn maintenance equipment or other service equipment that may roll over the box. If the box will be subject to excessive wheel loading, additional protection shall be provided.

SECTION 16. Zones and Related Components

16.1 Automatic distributing valves shall include clear Schedule 40 piping on the output of each zone.

16.2 Check valves shall not be required if separate return lines are used to isolate returned wastewater to the pretreatment system.

SECTION 17. Pressure Regulators

17.1 Regulators shall be selected to allow sufficient pressure and fiows for flushing. Pressure regulators shall be designed for use in wastewater drip dispersal system.

SECTION 18. System Installation

18.1 Protect the site prior to and after the installation of the drip system. Activities on the site shall be limited only to what is necessary for the installation of the system.

18.2 Any clearing or grubbing shall be performed based on a site-specific plan, which minimizes the disturbance of the soil and protects the overall soil characteristics. It may be necessary to use flexible PVC tubing to work around or over objects in the dispersal field; however, the number of emitters shall not be reduced.

18.3 Drip tubing shall not be installed when the soil is wet or frozen.

18.4 Drip tubing shall be installed on contour.

18.5 Flexible Schedule 40 PVC tubing shall be used at each manifold connection to provide additional crimping protection and to prevent the tubing from being pulled out of the supply or return manifold as the soil settles.

18.6 Drip tubing shall be taped, plugged or capped when cut. All piping shall be taped or capped at the end of the construction day.

18.7 PVC pipe cutters that cleanly shear the pipe or tubing shall be used rather than sawing the pipe or tubing.

18.8 Complete flushing of the supply line prior to the connection of the drip tubing shall be performed. Sufficient volume of water shall be used to ensure all debris is removed from both the supply line and the drip tubing.

18.9 A start-up system check shall be performed before the system is placed in operation. All operational functions that would be expected during routine operations shall be performed in a specified time period of not less than 24 hours. This operational test shall include but not be limited to: timed dose functions, volume loading, flow rates, pressures at the inlet and outlet of each zone, pressures at the inlet and outlet of filters, leak detection, flushing, and alarms.

18.10 Repairs or modifications shall be made to eliminate any wet spot.

18.11 The establishment of a vegetative cover is critical to the overall performance of a drip dispersal system. The dispersal area shall be covered with sod or mulch as soon as possible after the installation of the drip tubing.

SECTION 19. System Operation and Maintenance

19.1 Periodic servicing shall be required. The frequency of the service period is dependent on the operational parameters set for the system by its designer. The minimal service period shall not be less than once every three (3) months.

19.2 Alarms resulting from mechanical break downs shall be investigated and the situation causing the alarm resolved.

19.3 Owners of Drip Dispersal Systems are required to maintain a Maintenance and Monitoring Contract with Maintenance Personnel certified by the Department for the life of the system.

SECTION 20. System Design

20.1 The following procedure shall be used to determine the minimum surface area required for drip dispersal system.

20.2 The depth and duration of the seasonal water table shall be determined.

20.3 The sizing and loading rate chart found in Table 1, 2 and 3 of this manual shall be used to determine the amount of surface area required for installation.

20.4 The spacing between drip tube laterals shall not be less than two (2) ft. Center to enter. Drip tube laterals spacing may be greater than two (2) ft. however, for the purpose of determining the length of tubing required for a dispersal field, all length calculation shall be two (2) ft. center to center.

20.5 The effective area of the dispersal field shall be calculated by dividing the daily wastewater flow rate (DWF) in gallons per day (gpd) by the soil loading rate (SLR) in gallons per foot square per day (g/ft ft'! d). [Area of the dispersal field (DF) = design wastewater flow (DWF) soil loading rate (SLR).]

20.6 The length of the drip tubing shall be determined by dividing the dispersal field (DF) required by the drip tube spacing (DT) of two (2) Ft. [Drip tube length (DTL = dispersal field area (DF) drip tube spacing (DT) of two (2) ft.]

20.7 The number of emitters required shall be determined by dividing the drip tube length (DTL) by the emitter spacing (E) ft. [Drip line lateral length (ft.) emitter spacing (ft.) = Number of emitters.]

20.8 The loading rate for a soil which has a rock substrata (consolidated or fractured) and no seasonal water tables present above the rock substrata shall be sized as a moderate seasonal water table.

SECTION 21. Training and Certification

21.1 All Designated Representatives, Installers, Environmental Health Specialists, and Certified Maintenance Personnel shall be certified in the design, construction, and maintenance of a drip dispersal system. The certification program will be provided or approved by the Department Onsite Wastewater Section.

SECTION 22. Variances and Exemptions

22.1 Requested variations from these Rules and Regulations will be considered and maybe approved at the sole discretion of the Department.

22.2 Submission of proposed experimental onsite wastewater systems may be approved, disapproved, or approved on a trial basis for a specific period of time. Such approval or disapproval shall be at the sole discretion of the Department. Submission of an experimental design shall include data as to the efficiency of operation of the proposed experimental system. A monitoring plan shall be submitted for approval in addition to the system design.

22.3 Good management practices are additions or modifications to systems which will make such systems more efficient, or which could make such systems acceptable in certain soil conditions. Where good management practices are proposed for inclusion in a drip dispersal system, approval shall be at the sole discretion of the Department or its Authorized Agent.

SECTION 23. Fees

23.1 A fee shall be levied for the review of individual drip dispersal system permit application pursuant to A.C.A. § 14-236-116.

23.2 For structures one thousand five hundred square feet (1,500 sq. ft.) or less, the fee to review a permit application is thirty dollars ($30.00).

23.3 For structures more than one thousand five hundred square feet (1,500 sq. ft.) and less than two thousand square feet (2,000 sq. ft.), the fee to review a permit application is forty-five dollars ($45.00).

23.4 For structures more than two thousand square feet (2,000 sq. ft.) and less than three thousand square feet (3,000 sq. ft.), the fee to review a permit application is ninety dollars ($90.00).

23.5 For structures more than three thousand square feet (3,000 sq. ft.) and less than four thousand square feet (4,000 sq. ft.), the fee to review a permit application is one hundred twenty dollars ($120.00).

23.6 For structures four thousand (4,000 sq. ft.) and greater, the fee to review a permit application is one hundred fifty dollars ($150.00)

23.7 For the alteration, repair, or extension of any individual drip dispersal system, the fee to review a permit application is thirty dollars ($30.00).

23.8 In calculating the square footage of a residential structure for purposes of determining the applicable fee under this section the square footage of all auxiliary areas of the residential structure shall not be considered.

23.9 Auxiliary areas include garages, carports, porches, and other similar areas as determined by the Department.

23.10 Non-individual or multi structure permit submittals shall include a Cost Estimate Worksheet (EHP-17).

SECTION 24. Penalties

24.1 Any person, firm, corporation or association who violates any of the provisions of Act 402 of 1977, as Amended, or any Rules and Regulations promulgated under the authority of Act 402 of 1977, as Amended, shall upon conviction, be deemed guilty of a misdemeanor and shall be punished by a fine of not less than one hundred dollars ($100.00) nor more than one thousand dollars ($1,000.00)

SECTION 25. Severability

25.1 If any provisions of these Rules, or the application thereof to any person is held invalid, such invalidity shall not affect other provisions or applications of these Rules, which can affect without the invalid provisions of application, and to this end the provisions hereto are declared to be severable.

SECTION 26. Repeal

26.1 All Regulations and parts of Regulations in conflict herewith are hereby repealed.

SECTION 27. Certification

This will certify that the foregoing Rules Pertaining to Drip Dispersal Systems were adopted by the Arkansas Department of Health at a regular session of the Board of Health on 28th of October, 2021.

TABLE 1

DRIP DISPERSAL FIELD SIZING AND LOADING RATE CHART FOR MODERATE HYDRAULIC CONDUCTIVITY SOILS

Brief SWT

Mod SWT

Long SWT

DEPTH TO RMF (inches)

(g/ft2/d)

ft2/100 Gal./Day

fe/ft2/d)

ft2/100 Gal./Day

(g/ft2/d)

FT2/100 Gal./Dav

1

0.021

4761.9

0.007

14285.71

0.003

33333.33

2

0.041

2439.02

0.014

7142.86

0.007

14285.71

3

0.062

1612.9

0.021

4761.9

0.010

10000

4

0.082

1219.51

0.027

3703.7

0.014

7142.86

5

0.103

970.87

0.034

2941.18

0.017

5882.35

6

0.123

813.01

0.041

2439.02

0.021

4761.9

7

0.144

694.44

0.048

2083.33

0.024

4166.67

8

0.164

609.76

0.055

1818.18

0.027

3703.7

9

0.185

540.54

0.062

1612.9

0.031

3225.81

10

0.205

487.8

0.068

1470.59

0.034

2941.18

11

0.226

442.48

0.075

1333.33

0.038

2631.58

12

0.246

406.5

0.082

1219.51

0.041

2439.02

13

0.267

374.53

0.089

1123.6

0.044

2272.73

14

0.287

348.43

0.096

1041.67

0.048

2083.33

15

0.308

324.68

0.103

970.87

0.051

1960.78

16

0,328

304.88

0.109

917.43

0.055

1818.18

17

0.349

286.53

0.116

862.07

0.058

1724.14

18

0.369

271

0.123

813.01

0.062

1612.9

19

0.390

256.41

0.130

769.23

0.065

1538.46

20

0.410

243.9

0.137

729.93

0.068

1470.59

21

0.431

232.02

0.144

694.44

0.072

1388.89

22

0.451

221.73

0,150

666.67

0.075

1333.33

23

0.472

211.86

0,157

636.94

0.079

1265.82

24

0.492

203.25

0,164

609.76

0.082

1219.51

25

0.513

194.93

0,171

584.8

0.085

1176.47

26

0.533

187.62

0,178

561.8

0.089

1123.6

27

0.554

180.51

0,185

540.54

0.092

1086.96

28

0.574

174.22

0,191

523.56

0.096

1041.67

29

0.595

168.07

0,198

505.05

0.099

1010.1

30

0.615

162.6

0,205

487.8

0.103

970.87

31

0.636

157.23

0,212

471.7

0.106

943.4

32

0.656

152.44

0,219

456.62

0.109

917.43

33

0.677

147.71

0.226

442.48

0.113

884.96

34

0.697

143.47

0.232

431.03

0.116

862.07

35

0.718

139.28

0.239

418.41

0.120

833.33

36

0.738

135.50

0.246

406.5

0.123

813.01

37

0.750

133.33

0.253

395.26

0.126

793.65

38

0.750

133.33

0.260

384.62

0,130

769.23

39

0.750

133.33

0.267

374.53

0,133

751.88

40

0.750

133.33

0.273

366.3

0.137

729.93

41

0.750

133.33

0.280

357.14

0.140

714.29

42

0.750

133.33

0.287

348.43

0.144

694.44

43

0.750

133.33

0.294

340.14

0.147

680.27

44

0.750

133.33

0.301

332.23

0.150

666.67

45

0.750

133.33

0.308

324.68

0.154

649.35

46

0.750

133.33

0.314

318.47

0.157

636.94

47

0.750

133.33

0.321

311.53

0.161

621.12

48

0.750

133.33

0.328

304.88

0.164

609.76

TABLE 2

DRIP DISPERSAL FIELD SIZING AND LOADING RATE CHART FOR LOW HYDRAULIC CONDUCTIVITY SOILS

Brief SWT

Mod SWT

Lone SWT

DEPTH TO RMF (inches)

(g/ft2/d)

FT2/100 Gal./Dav

(g/ft2/d)

FT2/100 Gal./Day

(g/ft2/d)

FT2/100 Gal./Day

1

0.014

7142,86

0,005

20000

0.002

50000

2

0.028

3571,43

0,009

11111,11

0.005

20000

3

0.042

2380,95

0,014

7142,86

0.007

14285,71

4

0,055

1818,18

0,018

5555,56

0.009

11111,11

5

0.069

1449,28

0,023

4347,83

0.012

8333,33

6

0.083

1204.82

0,028

3571,43

0.014

7142,86

7

0.097

1030.93

0,032

3125

0.016

6250

8

0.111

900.9

0,037

2702,7

0.018

5555,56

9

0.125

800

0,042

2380,95

0.021

4761,9

10

0.139

719.42

0,046

2173,91

0.023

4347,83

11

0.152

657.89

0,051

1960,78

0.025

4000

12

0.166

602.41

0,055

1818,18

0.028

3571,43

13

0,180

555.56

0,060

1666,67

0.030

3333,33

14

0,194

515.46

0,065

1538,46

0,032

3125

15

0,208

480.77

0,069

1449,28

0,035

2857,14

16

0,222

450.45

0,074

1351,35

0.037

2702,7

17

0,235

425.53

0,078

1282,05

0,039

2564,1

18

0,249

401.61

0,083

1204,82

0,042

2380,95

19

0,263

380.23

0,088

1136,36

0,044

2272,73

20

0,277

361.01

0,092

1086,96

0,046

2173,91

21

0,291

343.64

0,097

1030,93

0,048

2083,33

22

0,300

333.33

0,102

980,39

0,051

1960,78

23

0,300

333.33

0,106

943,4

0,053

1886,79

24

0,300

333.33

0,111

900,9

0,055

1818,18

25

0,300

333.33

0,115

869,57

0,058

1724,14

26

0,300

333.33

0,120

833,33

0,060

1666,67

27

0,300

333.33

0,125

800

0,062

1612,9

28

0,300

333,33

0,129

775,19

0,065

1538,46

29

0,300

333,33

0,134

746,27

0,067

1492,54

30

0,300

333,33

0,139

719,42

0,069

1449,28

31

0,300

333,33

0,143

699,3

0,072

1388,89

32

0,300

333,33

0,148

675,68

0,074

1351,35

33

0,300

333,33

0,152

657,89

0,076

1315,79

34

0,300

333,33

0,157

636,94

0,078

1282,05

35

0,300

333,33

0,162

617,28

0,081

1234,57

36

0,300

333,33

0,166

602,41

0,083

1204,82

37

0,300

333,33

0,171

584,8

0,085

1176,47

38

0,300

333,33

0,175

571,43

0,088

1136,36

39

0,300

333,33

0,180

555,56

0,090

1111,11

40

0,300

333,33

0,185

540,54

0,092

1086,96

41

0,300

333,33

0,189

529,1

0,095

1052,63

42

0,300

333,33

0,194

515,46

0,097

1030,93

43

0,300

333,33

0,199

502,51

0,099

1010,1

44

0,300

333,33

0,203

492,61

0,102

980,39

45

0,300

333,33

0,208

480,77

0,104

961,54

46

0,300

333,33

0,212

471.7

0,106

943,4

47

0,300

333,33

0,217

460.83

0,109

917,43

48

0,300

333,33

0,222

450.45 1

0,111

900,9

TABLE 3

DRIP DISPERSAL FIELD SIZING AND LOADING RATE CHART FOR HIGH HYDRAULIC CONDUCTIVITY SOILS

Brief SWT

Mod SWT

Lona SWT

DEPTH TO RMF (inches)

(g/ft2/d)

Ft2/100 Gal./Day

(g/ft2/d)

FT2/100 Gal./Dav

(g/ft2/d)

FT2/100 Gal./Day

1

0.249

402

0.042

2381

0.021

4762

2

0.374

267

0.063

1205

0.042

2381

3

0.499

200

0.125

800

0.062

1613

4

0.623

161

0.166

602

0.083

1205

5

0.748

134

0.208

481

0.104

962

6

0.873

115

0.249

402

0.125

800

7

0.997

100

0.291

344

0.145

690

8

1.122

89

0.332

301

0.166

602

9

1.247

80

0.374

267

0.187

535

10

1.250

80

0.416

240

0.208

481

11

1.250

80

0.457

219

0.229

437

12

1.250

80

0.499

200

0.249

402

13

1.250

80

0.540

185

0.270

370

14

1.250

80

0.582

172

0.291

344

15

1.250

80

0.623

161

0.312

321

16

1.250

80

0.665

150

0.332

301

17

1.250

80

0.706

142

0.353

283

18

1.250

80

0.748

134

0.374

267

19

1.250

80

0.790

127

0.395

253

20

1.250

80

0.831

120

0.416

240

21

1.250

80

0.873

115

0.436

229

22

1.250

80

0.914

109

0.457

219

23

1.250

80

0.956

105

0.478

209

24

1.250

80

0.997

100

0.499

200

25

1.250

80

1.039

96

0.519

193

26

1.250

80

1.081

93

0.540

185

27

1.250

80

1.122

89

0.561

178

28

1.250

80

1.164

86

0.582

172

29

1.250

80

1.205

83

0.603

166

30

1.250

80

1.247

80

0.623

161

31

1.250

80

1.250

80

0.644

155

32

1.250

80

1.250

80

0.665

150

33

1.250

80

1.250

80

0.686

146

34

1.250

80

1.250

80

0.706

142

35

1.250

80

1.250

80

0.727

138

36

1.250

80

1.250

80

0.748

134

37

1.250

80

1.250

80

0.769

130

38

1.250

80

1.250

80

0.790

127

39

1.250

80

1.250

80

0.810

123

40

1.250

80

1.250

80

0.831

120

41

1.250

80

1.250

80

0.852

117

42

1.250

80

1.250

80

0.873

115

43

1.250

80

1.250

80

0.894

112

44

1.250

80

1.250

80

0.914

109

45

1.250

80

1.250

80

0.935

107

46

1.250

80

1.250

80

0.956

105

47

1.250

80

1.250

80

0.977

102

48

1.250

80

1.250

80

0.997

100

Disclaimer: These regulations may not be the most recent version. Arkansas may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.