Historical Note
New Section adopted by final rulemaking at 7 A.A.R. 1458, effective March 16, 2001 (Supp. 01-1).
Appendix A. Modified Appendix I
I 1 Private Sewage Disposal - General
(a) Where permitted by Section 713.0, the building sewer may be connected to a private sewage disposal system complying with the provisions of this appendix. The type of system shall be determined on the basis of location, soil absorption rate, soil classification, and depth to the ground water below the land surface and shall be designed to receive all sewage from the property. The system, except as otherwise approved, shall consist of a septic tank with effluent discharging into a subsurface disposal field, into one or more seepage pits, or into a combination of subsurface disposal field and seepage pits. The Administrative Authority may grant exceptions to the provisions of this appendix for permitted structures which have been destroyed due to fire or natural disaster, and which cannot be reconstructed in compliance with these provisions.
(b) Where the quantity or quality of the sewage is such that the above system cannot be expected to function satisfactorily; for commercial, agricultural, and industrial plumbing systems; for installations where appreciable amounts of industrial or indigestible wastes are produced; for occupancies producing abnormal quantities of sewage or liquid waste; or when grease interceptors are required by other parts of this Code, the method of sewage treatment and disposal shall be first approved by the Administrative Authority. Special sewage disposal systems for minor, limited, or temporary uses shall be first approved by the Administrative Authority. This appendix applies only to systems with an inflow of 3000 gallons (11,355 liters) per day or less.
(c) Disposal systems shall be designed to utilize the most porous or absorptive portions of the soil formation. Where the depth to the ground water extends to within the specified minimum vertical separation for the proposed system, a private sewage disposal system shall not be installed.
(d) The minimum vertical separation from the bottom of the disposal field or seepage pit shall be as specified in Tables I-4 (A), I-4 (B), I-5 or I-7.
(e) When making a site investigation and determining the soil characterization and soil absorption rates for private sewage disposal systems and alternative private sewage treatment and disposal systems, an investigator shall use one or more of the following standards, including (1) through (7), incorporated by reference, or methods or equivalent standards approved by the Administrative Authority. The incorporated standards do not include later amendments or editions and are available from the Registrar of Contractors and the Office of the Secretary of State:
(1) ASTM D 5879-95, "Standard Practice for Surface Site Characterization for On-Site Septic Systems";
(2) ASTM D 5921-96, "Standard Practice for Subsurface Site Characterization of Test Pits for On-Site Septic Systems";
(3) ASTM D 1452-80 (Reapproved 1995), "Standard Practice for Soil Investigation and Sampling by Auger Borings." This method shall be used in areas if the depth to groundwater may be within the required minimum vertical separation from the bottom of the subsurface disposal field for the private sewage disposal system;
(4) ASTM C1227-00, "Standard Specification for Precast Concrete Septic Tanks";
(5) IAPMO PS1-93, "Material and Property standard for Prefabricated Septic Tanks";
(6) ACI 318-99, "Building Code Requirements for Structural Concrete" and ACI 318R-99, "Commentary";
(7) ACI 350R-89, "Environmental Engineering Concrete Structures", or
(8) Percolation testing as specified in Section I 15.
(f) A site investigation shall include a log of soil formations, percentage of rock, texture, structure, consistence, and mottles as provided in ASTM D-5921-96, depth to ground water below the land surface as determined by test holes dug in close proximity to any proposed disposal field or seepage pit (for example, published groundwater data, subdivision reports, or relevant well data), soil classification, or percolation test results. Other information acceptable to the Administrative Authority may be utilized to determine soil performance equivalent to that achieved by the standards or methods specified in Section I 1 (e).
(g) All private sewage disposal systems shall be so designed that additional seepage pits or subsurface drain fields, equivalent to at least 100% of the required original system, may be installed if the original system cannot absorb all the sewage. No division of the lot or erection of structures on the lot shall be made if such division or structure impairs the usefulness of the 100% expansion area.
(h) No property shall be improved in excess of its capacity to treat and dispose of sewage effluent by the means provided in this Code.
(i) No private sewage disposal system, or part thereof, shall be located in any lot other than the lot which is the site of the building or structure served by such system; nor shall any private sewage disposal system or part thereof, be located at any point having less than the minimum distances indicated in Table I-1.
Nothing in this Code shall be construed to prohibit the use of all or part of an abutting lot to provide additional space for a private sewage disposal system or part thereof, when proper cause, transfer of ownership, or change of boundary not in violation of other requirements has been first established to the satisfaction of the Administrative Authority. The instrument recording such action shall constitute an agreement with the Administrative Authority which shall clearly state and show that the areas so joined or used shall be maintained as a unit during the time they are so used. Such agreement shall be recorded in the office of the County Recorder as part of the conditions of ownership of said properties, and shall be binding on all heirs, successors, and assigns to such properties. A copy of the instrument recording such proceedings shall be filled with the Administrative Authority.
(j) No building permit shall be issued until the Administrative Authority has approved the site for a private sewage disposal system.
(k) Nothing contained in this appendix shall be construed to prevent the Administrative Authority from requiring compliance with statutes, ordinances, or rules having higher requirements than those contained herein, where such statutes, ordinances, or rules are essential to maintain a safe and sanitary condition.
(1) Exception: The Administrative Authority may, at its discretion, approve an alternative private sewage treatment and disposal system.
I 2 Definitions
(a) Administrative Authority - A municipality or county that enforces the state plumbing code. The director of the Arizona Department of Environmental Quality may delegate functions, powers, or duties to a municipality or county under A.R.S. § 49-107.
(b) Aggregate - Clean graded hard rock or gravel. Aggregate shall have not more than 2% fines by weight. Aggregate shall be of uniform size, 3/4 inches (19.1 mm) to 2 1/2 inches (63.5 mm) in diameter, and shall offer 30% or more void space. The aggregate shall have a hardness value of three or greater on the Moh's Scale of Hardness (aggregate that can scratch a copper penny without leaving any residual rock material on the coin would be a hardness of three or more on the Moh's Scale of Hardness). Volcanic rock that meets the above criteria may be substituted for hard rock or gravel.
(c) Bedroom - A habitable room providing privacy and used for sleeping purposes. For the purposes of this Code, a loft or a basement shall be considered a bedroom.
(d) Disposal Area - Area within the horizontal plane that is delineated by a simple figure that encompasses the soil absorption components of a wastewater system.
(e) Disposal Bed - A type of bottom area absorption system that uses an underground area up to 12 feet (3.7 m) wide, partially filled with aggregate. Piping distributes the effluent evenly throughout the entire bed.
(f) Disposal Field (Drainfield) - An aggregate-filled bed or trench into which effluent is discharged for final treatment and disposal. A soil absorption system is constructed to permit the discharge of treated sewage effluent into native soil. Construction is performed following site-specific specifications including soil excavation and the installation of disposal piping, aggregate, and other specified components and materials. The plan view of a drainfield shows the disposal area. The soil absorption area of a drainfield is the total surface within a drainfield that is approved by the Administrative Authority for the discharge of treated sewage effluent into the native soil.
(g) Disposal Pipe - Pipe that is placed in disposal trenches, beds, or a seepage pit to disperse effluent to the soil absorption surfaces.
(h) Disposal Pit (Seepage Pit) - A type of sidewall absorption system that uses a vertical, cylindrical underground excavation constructed to permit disposal of effluent by soil absorption through the pit's walls.
(i) Disposal Trench - A type of absorption trench that uses an area, excavated 1 foot (.3 m) to 3 feet (.9 m) wide, which contains aggregate and a single effluent disposal pipe.
(j) Distribution Box - A watertight structure that receives and distributes effluent in equal portions to two or more pipes that convey effluent to disposal pipes.
(k) Domestic Water Source Intake - A point of water intake or a suction pipeline located in any stream, lake, or reservoir that is used for the purpose of providing water for human consumption.
(l) Dosing Tank - A watertight receptacle located between the treatment unit and the drainfield, equipped with a pump or siphon, that stores and delivers doses of treated sewage effluent to the drainfield.
(m) Dry Wash - A watercourse that only flows in direct response to precipitation and whose channel at all times is above the water table.
(n) Effective Absorption Area - Area of native soil that is approved by the Administrative Authority for the absorption of treated sewage effluent in a disposal trench, pit, or other approved drainfield.
(o) Failure - The inability of any disposal system component to function as designed.
(p) Five-Day Biochemical Oxygen Demand (BOD) - The quantity of oxygen used in the biochemical oxidation of organic matter in five days at 20 degrees Centigrade under specific conditions and reported as milligrams per liter (mg/l).
(q) Groundwater - Water that is in the zone of saturation and under pressure equal to or greater than atmospheric pressure.
(r) Impermeable layer - A soil zone with a percolation rate numerically greater than 120 minutes per inch or soils classified as impermeable (for example: clay or rock).
(s) Live stream - A watercourse with perennial flow or where surface water is present at least 10% of the time during a calendar year, based upon historic flow or weather records.
(t) Mottles - Soil color patterns caused by alternating saturated (anaerobic) and unsaturated (aerobic) soil conditions.
(u) Percolation Test - An empirical test used to estimate the rate at which effluent is absorbed by the soil.
(v) Repair - The extension, alteration, replacement, or relocation of existing components of a private sewage disposal system.
(w) Rock - A body of consolidated or partially consolidated material, composed of minerals and located at or below the land surface. Rock includes bedrock (fractured or unfractured) and partially-weathered rock that is relatively hard and cannot be dug with a hand shovel.
(x) Septage - All sludge, scum, liquid, or other material treated using a private sewage disposal system.
(y) Site - The location of an existing or proposed private sewage disposal system.
(z) Site Investigation - The practice of investigating, evaluating, and reporting on soil, topographic, and location conditions that affect the design and function of a private sewage disposal system.
(aa) Soil Evaluation - The practice of investigating, characterizing, and reporting the properties of soil used to absorb treated sewage effluent in a zone of unsaturated flow.
(ab) Soils - The naturally occurring, unconsolidated mineral and organic material on the land surface, developed from rock and other parent material that consists of sand, silt, and clay-sized particles and variable amounts of organic matter. In a zone of transition between two types of soil, the soil will be classified according to those soil characteristics that represent 51% or more of the total zone.
(ac) Soil Profile - A vertical cross-section of the undisturbed soil showing the characteristic soil horizontal layers or soil horizons that have formed as a result of the combined effects of parent material, topography, climate, biological activity, and time.
(ad) Total Suspended Solids (TSS) - Solids in wastewater that can readily be removed by standard filtering procedures in a laboratory and reported in milligrams per liter (mg/l).
I 3 Capacity of Septic Tanks
The design liquid capacity of all septic tanks shall conform to Table I-2 and I-3.
I 4 Area of Disposal Fields
The minimum effective absorption area in disposal fields and estimated waste/sewage flow rate shall conform to Tables I-3, I-4 (A), I-4 (B) and I-7 and shall be as follows:
(1) When disposal fields are installed, a minimum of 150 square feet (13.9 sq. m) of trench bottom shall be provided for each system exclusive of any hard pan, rock, clay, or other impervious formations. Sidewall area in excess of the required 12 inches (30.5 cm) and not to exceed 36 inches (91.4 cm) below the disposal pipe may be added to the trench bottom area when computing absorption areas.
(2) When leaching beds are installed in lieu of trenches, the area of each such bed shall be at least 50% greater than the tabular requirements for trenches. Perimeter sidewall area in excess of the required 12 inches (30.5 cm) and not to exceed 36 inches (91.4 cm) below the disposal pipe may be added to the trench bottom area when computing absorption areas.
(3) No excavation for a disposal pipe or disposal bed shall extend within the system's specified minimum vertical separation in order to ensure the system does not contaminate the underlying groundwater in excess of Arizona Aquifer Water Quality standards.
(4) When leaching chambers are installed in lieu of pipe and aggregate, an equivalent absorption area shall be provided based on the calculated effective chamber absorption area. The calculated effective chamber absorption area is the nominal open-bottom absorption area (length times width) times 1.43, plus the product of two times the vertical height of the sidewalls times the chamber length. The sidewall chamber shall provide a minimum of 35% open area for side wall credit to be allowed, and shall be constructed to minimize the movement of fines into the chamber area. The use of filter fabric or geotextile against sidewall openings is prohibited. The required minimum absorption area shall be calculated using table I-4 (A), I-4 (B) or I-7.
Example:
The chamber to be used has an open bottom 3 feet wide, 6 feet long, and has 1 vertical foot (0.9 m, 1.8 m, and 0.3 m deep) of sidewall. The disposal system is for a 3-bedroom dwelling. The soil is loamy sand (N). Depth of chamber bottom is to be less than 5 feet (1.5 m) below the finished grade (the installation is considered a shallow system).
The calculated effective chamber absorption area per chamber is:
Chamber bottom area = 3 feet x 6 square feet (0.9 x 1.8 sq. m.) of open bottom area x 1.43 = 25.74 square feet (2.39 sq. m.), plus
Chamber sidewall = 2 sidewalls x 1 foot high x 6 feet long = 12 square feet (2 x 0.30 m. x 1.83 m. = 1.11 sq. m.).
The effective chamber absorption area = the chamber bottom plus sidewalls
Chamber sidewall = 25.74 square feet (2.39 sq. m.) + 12 square feet (1.11 sq. m.) = 37.74 square feet (3.5 sq. m.) per chamber.
The number of chambers needed is calculated as follows:
Wastewater flow rate is three bedrooms x 150 gallons per day (568 lpd), or 450 gallons per day (1703 lpd). The soil application rate for loamy sand [Table I-4 (A), Question N, Column A] is listed as 0.80 gallons per day per square foot (32.6. lpd/sq. m.) Dividing the flow rate, 450 gallons per day (1703 lpd), by the soil application rate, 0.80 gpd/sq. ft. (32.6 lpd/sq. m) yields a total absorption area of 562.5 square feet (52.3 sq. m.). Since the effective chamber absorption area of each chamber is 37.74 square feet (3.5 sq. m.), a total of 14.9 chambers are needed.
Required area = 562.5 sq. ft. (52.3 sq. m.) divided by 37.74 sq. ft. (3.5 sq. m.).
Round up to a total chamber requirement of 15 chambers.
I 5 Area of Seepage Pits
The minimum effective absorption area in any seepage pit shall be predicated on estimated waste/sewage flow rates in Table I-3 and shall conform to Tables I-5 and I-6 as follows:
(1) The minimum effective absorption area in any seepage pit shall be calculated as the excavated sidewall area below the inlet exclusive of any hardpan, rock, clay, or other impervious formations.
(2) Seepage pit sizes may be computed from Table I-5 or using percolation tests prescribed in I 15.
(3) The minimum required area of porous formation shall be provided in one or more seepage pits. No seepage pit excavation shall extend into the system's specified minimum vertical separation from the water table nor to a depth where sewage may contaminate the underlying groundwater that is protected by state law for domestic or drinking water purposes.
(4) The applicant shall supply acceptable evidence of depth to groundwater to the Administrative Authority.
(5) A boring log that describes soil from the seepage pit shall be submitted to the Administrative Authority.
I 6 Soil Testing
Seepage pit and disposal field sizes shall be computed from Tables I-4 (A), I-4 (B), I-5, I-6, and I-7.
I 7 Septic Tank Design and Construction
(a) All septic tanks shall meet the specifications set forth in I 7, (b) through (q).
(b) Septic tank designs shall produce a clarified effluent and shall provide adequate space for sludge and scum accumulations.
(c) Septic tanks shall be constructed of solid durable materials, not subject to excessive corrosion or decay and shall be watertight.
(d) Septic tanks shall have a minimum of two compartments except when placed in series. The inlet compartment of any septic tank not placed in series shall be nominally 67 to 75% of the total required capacity of the tank. Septic tanks placed in series shall be considered as a unit and shall meet the same criteria as a single tank. The liquid depth of the septic tank shall not be less than 42 inches (1.07m). A septic tank of 1000 gallon capacity shall have a length of at least 8 feet (2.44m). For septic tanks of greater capacity, the tank length shall be at least two times but not more than three times the width.
(e) Access to each septic tank interior shall be provided by at least two access openings 20 inches (50.8 cm) in minimum dimension. One access opening shall be located over the inlet and one access opening shall be located over the outlet. Whenever a first compartment exceeds 12 feet (3.7 m) in length, an additional access opening shall be provided over the baffle wall. Access openings and risers, if needed, shall be constructed to ensure accessibility within 6 inches (0.15 m) below grade. A permanent surface marker appropriate to the site shall be provided for locating the septic tank access openings for maintenance.
(f) The inlet and outlet pipe openings shall be not less in size than the connecting sewer pipe. The vertical leg of a round inlet and outlet fittings shall not be less in size than the connecting sewer pipe nor less than 4 inches (10.1 cm). A baffle-type fitting shall have the equivalent cross-sectional area of the connecting sewer pipe and not less than a 4 inch (10.2 cm) horizontal dimension when measured at the inlet and outlet pipe inverts.
(g) The inlet and outlet pipe or baffle shall extend 4 inches (10.2 cm) above and at least 12 inches (30.5 cm) below the water surface. The invert of the inlet pipe shall be at a level not less than 2 inches (5.1cm) above the invert of the outlet pipe.
(h) Inlet and outlet pipe fittings or baffles, and compartment partitions shall have a free vent area equal to the required cross-sectional area of the house sewer or private sewer discharging therein to provide free ventilation above the water surface from the disposal field or seepage pit through the septic tank, house sewer, and stack to the outer air.
(i) The sidewalls shall extend at least 12 inches (30.5 cm) above the liquid depth. The cover of the septic tank shall be at least 2 inches (5.1 cm) above the top of the inlet fitting vent opening.
(j) Partitions or baffles between compartments shall be of solid, durable material and shall extend at least 4 inches (10.1 cm) above the liquid level. The open area of the baffle shall be between one and two times the open area of the inlet pipe or for a horizontal slot, shall be no more than 6 inches in height, and shall be located at the midpoint of the liquid level of the baffle. Wooden baffles are prohibited.
(k) Each tank shall be structurally designed to withstand all anticipated earth or other loads. All septic tank covers shall be capable of supporting an earth load of 300 pounds per square foot (14.4 kPa) for a minimum soil cover of 2 feet (0.61 m). When the top of the tank is greater than 2 feet (0.61 m) below finished grade, the septic tank and cover shall be capable of supporting an additional load of 150 pounds per square foot (7.2 kPa) for each additional foot of cover.
(l) Septic tanks installed under concrete or black top paving shall have the required access openings extended to grade in a manner acceptable to the Administrative Authority.
(m) The inlet and outlet ends of the tank shall be clearly and permanently marked on the outside of the tank with the terms "INLET" or "IN," and, "OUTLET" or "OUT," above, or to the right or left of the corresponding inlet and outlet openings.
(n) It is permissible to have septic tanks placed in series to meet the minimum septic tank capacity requirements.
(o) Materials
(1) Cast in Place Concrete Septic Tanks
All concrete septic tanks shall be protected from corrosion by coating with an approved bituminous coating by construction with a concrete mix incorporating 15% to 18% fly ash, or by other acceptable means. The coating shall extend to at least 4 inches (101.6 mm) below the water line, and shall cover all of the internal area above that point. Septic tanks constructed in place shall comply with the American Concrete Institute (ACI) standards 318-99, 318R-99, and 350R-89.
(2) Steel Septic Tanks
The minimum wall thickness of any steel septic tank shall be No. 12 U.S. gauge (0.109 cm) and each tank shall be protected from corrosion, both externally and internally, by an approved bituminous coating or by other acceptable means.
(3) Prefabricated septic tanks
Materials for precast concrete septic tanks shall comply with ASTM C1227-00. Materials for fiberglass or polyethylene septic tanks shall comply with IAPMO PS1-93. If any conflict exists between this appendix and ASTM C1227-00 or IAPMO PS1-93, the requirements of this appendix shall apply.
(4) Alternative materials
Septic tanks constructed of alternative materials may be approved by the Administrative Authority if they comply with approved, applicable standards in this Code.
(5) Prohibited Materials
Wooden, block, and bare steel septic tanks are prohibited.
(p) All tanks shall be clearly and permanently marked with the manufacturer's name and registered trademark, the month and year of manufacture, the maximum recommended depth of earth cover in feet or meters and the design liquid capacity of the tank. The markings shall be adequately protected from corrosion so as to remain permanent and readable over the life of the tank.
(q) A septic tank effluent filter approved by the Administrative Authority shall be installed on all new private sewage disposal systems. The filter shall prevent the passage of solids larger than 1/8 inch (3.2 mm) in diameter while under 2 feet (0.61 m) of hydrostatic head. The filter shall be constructed of materials that are resistant to corrosion and erosion and be of adequate size for the anticipated hydraulic and organic loading.
I 8 Disposal Fields
(a) Distribution lines shall be constructed of clay tile laid with open joints, perforated clay pipe, perforated high density polyethylene pipe, perforated ABS pipe, perforated PVC pipe, or other approved materials, provided that sufficient openings are available for distribution of the effluent into the trench area.
(b) Before placing aggregate or drain lines in a prepared excavation, all smeared or compacted surfaces shall be removed from trenches by raking to a depth of 1 inch (2.5 cm) and the loose material removed. Aggregate shall be placed in the trench to the depth and grade required by this section. Drainpipe shall be placed on aggregate in an approved manner. The drain lines shall than be covered with aggregate to the minimum depth required by this section and this covered with landscape filter fabric, geotextile, or similar porous material to prevent closure of voids with earth backfill. No earth backfill shall be placed over the aggregate cover until after inspection and acceptance.
Exception:
Listed or approved leaching chambers may be used in lieu of pipe and aggregate. Chamber installations shall follow this appendix for disposal fields, where applicable, and shall conform to manufacturer's installation instructions.
(c) A grade board staked in the trench to the depth of aggregate shall be utilized when distribution line is constructed with drain tile or a flexible pipe material which will not maintain alignment without continuous support.
(d) Where two or more drain lines are installed, an approved distribution box of sufficient size to receive all lateral lines and flows shall be installed at the head of each disposal field. The inverts of all outlets shall be level and the invert of the inlet shall be at least 1 inch (2.5 cm) above the outlets. Distribution boxes shall be designed to ensure equal flow and shall be installed on a stable level surface such as a concrete slab or natural or compacted soil. Concrete distribution boxes shall be protected from corrosion by coating with an appropriate bituminous coating, or constructed of concrete with a 15% to 18% fly ash content, or by other approved methods acceptable to the Administrative Authority.
(e) All laterals from a distribution box to the disposal field shall be approved pipe with watertight joints. Multiple disposal field laterals, wherever practicable, shall be of uniform length.
(f) Connections between a septic tank and a distribution box shall be laid with approved pipe with watertight joints on natural ground or compacted fill.
(g) Disposal fields and beds shall be constructed as specified in Tables I-4 (A) and I-4 (B) and the following criteria:
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Gravity Trenches
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Minimum
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Maximum
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Number of trenches
1
|
1
|
-
|
|
Length of trench
|
-
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100 feet (30.5 m)
|
|
Bottom width of trench
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12 inches (30.5 cm)
|
36 inches (91.4 cm)
|
|
Depth of cover over disposal pipe
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9 inches (22.9 cm)
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24 inches (61.0 cm)
2
|
|
Aggregate material under disposal pipe
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12 inches (30.5 cm)
|
-
|
|
Aggregate material over disposal pipe
|
2 inches (5.1 cm)
|
2 inches (5.1 cm)
|
|
Slope of disposal pipe
|
level
|
level
|
|
Disposal pipe diameter
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3 inches (7.6 cm)
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4 inches (10.1 cm)
|
|
Spacing of disposal pipe, or leaching
|
2 x effective depth
3
or 5 feet
(1.5 m) whichever is greater
|
|
Notes:
1
Two trenches are recommended.
2
For more than 24 inches (61.0 cm), SDR 35 or equivalent strength pipe is required.
3
The distance between the bottom of the disposal pipe and the bottom of the trench bed.
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Gravity Beds
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Minimum
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Maximum
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|
Number of disposal pipes
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2
|
-
|
|
Length of bed
|
-
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100 feet (30.5 m)
|
|
Distance between disposal pipes
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4 feet (1.2 m)
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6 feet (1.8 m)
|
|
Width of bed
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10 feet (3.0 m)
|
12 feet (3.66 m)
|
|
Distance from pipe to sidewall
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3 feet (0.91 m)
|
3 feet (0.91 m)
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|
Depth of cover over disposal pipe
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9 inches (22.9 cm)
|
14 inches (35.6 cm)
|
|
Aggregate material under disposal pipe
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12 inches (30.5 cm)
|
-
|
|
Aggregate material over disposal pipe
|
2 inches (5.1 cm)
|
2 inches (5.1 cm)
|
|
Slope of disposal pipe
|
level
|
level
|
|
Disposal pipe diameter
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3 inches (7.6 cm)
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4 inches (10.1 cm)
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Disposal fields, trenches and leaching beds shall not be paved over or covered by concrete or any material that can reduce or inhibit any possible evaporation of sewer effluent.
(h) When necessary on sloping ground to maintain a level disposal pipe, leach trenches or disposal beds shall be stepped. The lines between each horizontal leaching section shall be made with approved watertight joints and installed on natural or unfilled ground.
I 9 Seepage Pits
(a) Seepage pits constructed in accordance with this appendix are considered a method of disposing of septic tank effluent. Criteria used for determining the suitability of a seepage pit are contained in table I 5. The capacity of seepage pits shall be based on the quantity of liquid waste discharging there into, and on the character and porosity of the surrounding soil and shall conform to Section I 5 of this appendix.
(b) Multiple seepage pit installations shall be served through an approved distribution box or be connected in series by means of a watertight connection laid on undisturbed or compacted soil. The outlet from the pit shall have an approved sanitary tee with the vertical leg extending at least 12 inches (30.5 cm) below the inlet fitting.
(c) Each seepage pit shall be circular in shape and shall have an excavated diameter of not less than 4 feet (1.2 m). Approval shall be obtained prior to construction for any pit having an excavated diameter greater than 6 feet (1.8 m).
(d) For gravel filled seepage pits, the entire pit shall be backfilled with aggregate which shall be clean and of uniform gradation, 3/4 inch (1.9 cm) to 2 1/2 inches (6.4 cm) in diameter. Material used for backfill shall offer a minimum of 30% void space. Each pit shall have a breather/effluent conductor pipe, which shall consist of a perforated pipe at least 4 inches (10.2 cm), in diameter, placed vertically within the backfill of the pit. The pipe shall extend from the bottom of the pit to 12 inches below ground level.
(e) Lined, hollow pits shall be lined with concrete liner, or other approved materials and shall be laid on a firm foundation. Excavation voids behind the liner shall have a minimum of 9 inches (22.9 cm) of aggregate which shall be clean and of uniform gradation, 3/4 inch (1.9 cm) to 2 1/2 inches (6.4 cm) in diameter.
(f) The cover of a lined seepage pit shall be constructed of an approved one- or two-piece reinforced concrete slab of 2500 pounds per square inch (17,238 kPa) minimum compressive strength, not less than 5 inches (127 mm) thick and designed to support an earth load of not less than 400 pounds per square foot (19.2 kPa). Each cover shall be provided with a 12 inch (30.5 cm) minimum access hole with plug or cover and shall be coated on the underside with an approved bituminous seal or constructed of concrete with 15% to 18% fly ash content or other nonpermeable protective material. Each cover shall have at least a 4 inch (10.2 cm) inspection pipe placed vertically not more than 6 inches below ground level.
(g) The top of the seepage pit cover must be at least 18 inches (45.7 cm) but not more than 4 feet (1.2 m) below the surface of the ground.
(h) An approved vented inlet fitting shall be provided in every seepage pit to prevent the inflow from damaging the sidewall.
Exception: When using a one- or two-piece concrete slab cover inlet, the fitting may be a 1/4 bend fitting discharging through an opening in the top of the slab cover. For multiple seepage pit installations, the outlet fittings shall be per Section I 9 (b) of this appendix.
(i) Seepage pit design details are shown in Figure I-1 and I-2.
I 10 Cesspools
The use of cesspools for waste disposal is prohibited.
I 11 Interceptor Design Criteria for Private Sewage Disposal Systems
(a) When liquid wastes containing excessive amounts of grease, garbage, flammable wastes, sand, or other ingredients which may affect the operation of a private sewage disposal system, an interceptor for such wastes shall be installed.
(b) Installation of such interceptors shall comply with Section 1008.0 of the Uniform Plumbing Code and their location shall be in accordance with Table I-1 of this appendix.
(c) Sampling box shall be installed when required by the Administrative Authority.
(d) Interceptors shall be of approved design and be of not less than two compartments. Structural requirements shall be in compliance with the applicable subparts of Section I 7 of this appendix.
(e) Interceptors shall be located as close to the source as possible and be accessible for servicing. All necessary manholes for servicing shall be at grade level and be gas-tight.
(f) Waste discharge from interceptors may be connected to a septic tank or other primary system or be disposed into a separate disposal system.
(g) Recommended Design Criteria. Minimum design criteria for grease and garbage, commercial kitchens; sand-silt oil, auto washers; and silt-lint grease, laundries, and laundromats. (Formulae may be adapted to other types of occupancies with similar wastes or as determined by the Administrative Authority rules.)
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Grease and Garbage, Commercial Kitchens
|
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Number of Meals Waste Retention Storage Interceptor Size
per peak hour x Flow Rate x Time x Factor = (liquid capacity)
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|
Sand-Silt Oil, Auto Washers
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|
Number of Vehicles Waste Retention Storage Interceptor Size
per peak hour x Flow Rate x Time x Factor = (liquid capacity)
|
|
Silt-Lint Grease, Laundries, Laundromats
|
|
Number of 2 cycles Waste Retention Storage Interceptor Size
Machines x per hour x Flow Rate x Time x Factor = (liquid capacity)
|
Waste Flow Rate
See Table I-3 of this appendix for estimated flow rates.
|
Estimated Retention Times
|
|
Commercial kitchen waste:
Dishwasher and/or disposal
|
2.5 hours
|
|
Single Service kitchen:
Single serving with disposal
|
1.5 hours
|
|
Sand-silt-oil
|
2.0 hours
|
|
Lint-silt (laundry)
|
2.0 hours
|
|
Estimated Storage Factors
|
|
Fully equipped commercial kitchen
|
8 hour operation:
|
1.0
|
|
|
16 hour operation:
|
2.0
|
|
|
24 hour operation
|
3.0
|
|
Single service kitchen
|
|
1.5
|
|
Auto washers
|
Self-serve
|
1.5
|
|
|
Employee operated
|
2.0
|
|
Laundries, Laundromats
|
(allows for rock filter)
|
1.5
|
I 12 Inspection and Testing
(a) Private sewage disposal systems shall be inspected and tested prior to operation.
(b) Inspection shall be for the following purposes:
(1) To verify soil characteristics used for the basis of the design.
(2) To verify the installation of approved equipment and materials.
(3) To verify that construction was performed in accordance with the permit.
(4) To verify watertightness of the septic tank and other components.
(c) Field testing shall include:
(1) Septic tank watertightness - Watertightness shall be established before inspection. A tank failing the watertightness test must be repaired or replaced, and cannot be operated until it complies with watertightness requirements and has been inspected.
(2) Water test procedures - Tanks shall be filled to the invert of the outlet. Water shall be left standing in the tank for at least 24 hours before the inspection. After 24 hours, refill the tank, if necessary. Concrete may absorb some water. At the start of the inspection, record the initial water level and time. After one hour, record the time and the corresponding water level. A tank shall pass a watertightness test if the water level dropped less than 1/4 of an inch. A visible leak (flowing water) shall be considered a failure. A damp or wet spot that is not flowing is not considered a failure.
(3) Vacuum testing procedures - Vacuum testing may be used to determine watertightness in lieu of a water test. The tank shall be sealed and empty. A vacuum of 2 inches (5.1 cm) of mercury (1 psi or 69.1 gm/sq. cm) shall be applied and stabilized. The vacuum shall drop no more than 0.2 inches (0.5 cm) of mercury (0.1 psi or 6.9 gm/sq. cm) during the one hour test period.
(4) A flow test shall be performed through the system to the point of effluent disposal. All lines and components shall be watertight. Capacities, required air space, and fittings shall be in accordance with the provisions set forth in this appendix.
I 13 Abandoned Sewers and Sewage Disposal Facilities
(a) Every abandoned building (house) sewer, or part thereof, shall be plugged or capped in an approved manner within 5 feet (1.5 m) of the property line.
(b) Every cesspool, septic tank, alternative sewage disposal system, and seepage pit which has been abandoned or has been discontinued otherwise from further use or to which no waste or soil pipe from a plumbing fixture is connected, shall have the sewage removed therefrom, shall have all electrical and mechanical components disconnected and abandoned under the appropriate procedures in the uniform building or electrical code, as applicable, and be completely filled with earth, sand, gravel, concrete, or other approved material.
(c) The top cover or arch over the cesspool, septic tank, or seepage pit shall be removed before filling and the filling shall not extend above the top of the vertical portions of the sidewalls or above the level of any outlet pipe until inspection has been called and the cesspool, septic tank, or seepage pit has been inspected. After such inspection, the cesspool, septic tank, or seepage pit shall be filled to the level of the top of the ground.
(d) No person owning or controlling any cesspool, septic tank, or seepage pit on the premises of such person or in that portion of any public street, alley, or other public property abutting such premises, shall fail, refuse, or neglect to comply with the provisions of this section or upon receipt of notice so to comply from the Administrative Authority.
(e) Where disposal facilities are abandoned consequent to connecting any premises with the public sewer, the permittee making the connection shall fill all abandoned facilities as required by the Administrative Authority within 30 days from the time of connecting to the public sewer.
I 14 Drawings and Specifications
The Administrative Authority may require any or all of the following information before a permit is issued for a private sewage disposal system:
(1) A site specific plot plan drawn to scale, dimensioned, showing direction and approximate slope of surface (2 foot (0.6 m) contour lines), location of all present or proposed retaining walls, drainage channels, water supply lines or wells, paved areas and structures on the plot, number of bedrooms or plumbing fixtures in each structure and location of the private sewage disposal system with relation to lot lines and structures.
(2) Details of construction including system profile and construction sections necessary to assure compliance with the requirements of this appendix together with a full description of the complete installation including specifications describing all materials, equipment, construction, workmanship, and methods of assembly and installation.
(3) A log of the soil formations, percentage of rock, texture, structure, consistence, and mottles as provided in ASTM D-5921-96, or other practice acceptable, and depth to the groundwater below the land surface as determined by established records or test holes dug in close proximity to any proposed seepage pit or disposal field, together with a statement of water absorption characteristics of the soil at the proposed site as determined by site investigation and soil evaluation.
I 15 Percolation Testing, Soil Absorption Rate and Minimum vertical separation
(a) The following procedures are to be used for determining the system soil absorption rate and minimum vertical separation:
(1) Establish the primary area based on site suitability review including proposed improvements.
(2) Establish the reserve area based on site suitability review and the type of system.
(3) Excavate the test hole to the depth necessary to confirm soil conditions for the design of the proposed disposal trench, bed or seepage pit. For disposal trenches and beds, a minimum of one test hole at both the primary disposal area and the reserve area is required. For seepage pits, one test hole is required at the primary disposal area.
(4) For disposal trenches and beds, testing shall be performed at appropriate locations and depths within the soil profile to determine the rate at which the soil will absorb effluent. Percolation tests should be performed at each obvious strata change that would significantly effect the design, soil application rate or minimum vertical separation.
(5) For seepage pits, discount the thickness of any relatively impermeable soil profiles while determining the soil absorption rate.
(6) A test hole shall not be excavated within 3 feet (0.9 m) of a ledge in an observation pit. Care should be taken to assure adjacent features impacting the absorption rate are avoided.
(7) The test report shall include a site evaluation map locating the test hole(s).
(b) Disposal Trenches and Beds
(1) Area Preparation
(i) Dig a 12 inch square by 12 inches (30.5 cm x 30.5 cm) deep hole or a 15 inch round by 12 inches (38.1 cm x 30.5 cm) deep hole in undisturbed soil.
(ii) Scarify any smeared soil surfaces.
(iii) Remove loosened materials from the bottom of hole.
(2) Presoaking the Test Hole
(i) A system, such as a perforated bucket, can be used to support the sidewalls of the test hole if necessary. Fill any voids between the walls of the hole and the bucket with pea gravel.
(ii) Fill the test hole to 12 inches (30.5 m) above the bottom of the hole with clean water.
(iii) Observe the rate at which the water level drops in the hole and determine the time in minutes for the water to completely drain away.
(iv) If the water drains away in less than 60 minutes, repeat the procedure. If the water drains away in less than an additional 60 minutes, repeat the procedure a third time.
(v) Proceed immediately with testing if the water drains away three times in less than 60 minutes each time.
(vi) If the water does not drain after the third refill, maintain the water level in the test hole at a minimum depth of 9 inches (22.9 cm) for at least four hours. Wait for a minimum of 16 hours and a maximum of 24 hours before proceeding with the test.
(3) Conducting the Test
(i) Remove any materials that have sloughed into the test hole to be sure that the test hole has the dimensions indicated above.
(ii) Fill the hole with clean water to a depth of 6 inches (15.2 cm) above the bottom of the percolation test hole.
(iii) Measure the time it takes for the water level to drop exactly 1 inch (2.5 cm) from a fixed reference point. Record the drop in the water level. Care should be used to be sure that the measurement method does not have a significant impact on determination of the absorption rate.
(iv) Determine the stabilized absorption rate for the test hole. The approximate absorption rate can be determined by repetitively measuring the absorption rate until three consecutive values vary by no more than 10%. If three consecutive measurements indicate that the absorption rate is not approaching a steady rate or that the rate is close to a restrictive limit, an alternate method based on a graphical solution of the test data approximating the final stabilized rate is recommended.
(v) Record the test rate based on the above procedure.
(c) Seepage Pits
(1) Area Preparation
(i) Drill a test hole at least 18 inches (45.7 cm) in diameter to the depth of the bottom of the proposed seepage pit. The minimum hole depth is 30 feet (9.1 m). After the test, the diameter of the test hole may be enlarged to allow construction of the seepage pit at the same location.
(ii) Scarify any smeared soil surfaces.
(iii) Remove loosened materials from the bottom of the hole.
(2) Presoaking the Test Hole
(i) Fill the bottom 6 inches (15.2 cm) of the test hole with gravel, if necessary, to prevent scouring.
(ii) Fill the test hole with clean water up to 3 feet (0.9 m) below grade.
(iii) Observe the rate at which the water level drops in the hole and determine the time in minutes for the water to completely drain away.
(iv) If the water drains away in less than four hours, repeat the procedure.
(v) Proceed immediately with testing if the water drains away in less than four hours after the second refill.
(vi) If the water does not drain within four hours after the second refill, refill the hole a third time and wait for a minimum of 16 hours and a maximum of 24 hours before proceeding with the test.
(vii) If there is still standing water in the hole after the presoaking has been completed, the water shall not be removed from the hole.
(3) Conducting the Test
(i) Fill the hole with clean water up to 3 feet (0.9 m) below grade.
(ii) Measure the decline of the water level from a fixed reference point every 10 minutes until a stabilized absorption rate is obtained.
(iii) Determine the stabilized absorption rate by repetitively measuring the absorption rate until three consecutive values vary by no more than 10%. If three consecutive measurements indicate that the absorption rate is not approaching a steady rate or that the rate is close to a restrictive limit, an alternate method based on a graphical solution of the test data approximating the final stabilized rate is recommended.
(iv) Do not use test results from any relatively impermeable soil profiles while determining the stabilized soil absorption rate.
(v) Record the rate based on the above procedure.
Table I-1. Location of Sewage Disposal System
|
Point of Beginning for Setback Distance
|
Minimum Horizontal Setback
Distances in feet (meters)
|
|
|
Septic Tank
|
Disposal Trench/Bed or
Seepage Pit
|
|
Buildings
1
|
10 (3.0)
|
10 (3.0)
|
|
Property line adjoining private property
|
5 (1.5)
|
See footnote 2
|
|
Well (Public Water Supplies)
|
100 (30.5)
|
100 (30.5)
|
|
Wells (Private)
3
|
100 (30.5)
|
100 (30.5)
|
|
Live Streams
4
|
100 (30.5)
|
100 (30.5)
|
|
Lake or Reservoir
5
|
100 (30.5)
|
100 (30.5)
|
|
Domestic Water Source Intake
|
200 (61.0)
|
200 (61.0)
|
|
Dry Wash/Drainage Easement
6
|
50 (15.2)
|
50 (15.2)
|
|
Transmission Distribution Water Line
|
10 (3.0)
|
10 (3.0)
|
|
Domestic service Water Line
7
|
5 (1.5)
|
5 (1.5)
|
|
Cut on Sloping downgradient Terrain, Culverts and Roadway Ditches
8
|
15 (4.6)
|
15 (4.6) or 4 x the elevation difference between the finished grade at the point of beginning and the elevation at the cut bank bottom, ditch bottom, or culvert invert, whichever is greater, up to 50 feet (15.2 m)
|
|
Driveway
9
|
5 (1.5)
|
5 (1.5)
|
|
Swimming Pool
10
|
5 (1.5)
|
5 (1.5)
|
|
Any Easements (other than drainage easements)
11
|
5 (1.5)
|
5 (1.5)
|
Notes:
1
Including porches, decks and steps, whether covered or uncovered, breezeways, roofed patios, carports, covered walks, covered driveways, swimming pools, and similar structures and appurtenances.
2
The setback requirement is 5 feet (1.5 m) unless the property is not served by a central system for the distribution of water and:
(a) There is no existing or proposed individual well on adjoining private property, in which case the setback is 50 feet (15.2m); or
(b) A 100 foot (30.5m) separation distance cannot be maintained from an existing or proposed individual well, in which case the setback is the distance necessary to maintain the 100 foot (30.5m) separation; or
(c) The applicable setback requirement in (a) or (b) may be reduced to a minimum of 5 feet (1.5m) with a variance from the Administrative Authority.
3
For unaltered lots in a subdivision approved before October 1, 1986.
4
Measured from the nearest boundary of peak streamflow from a 10 year 24 hour precipitation event.
5
Measured from the elevation of high water line from a peak flow from a 10 year, 24 hour precipitation event at the spillway.
6
50 foot (15.2 m) setback is measured from the edge of the defined natural channel bank of a drainage area of more than five acres or a drainage easement whichever is less. Setback may be reduced to 25 feet (7.6 m) up gradient from the system, if channel erosion protection is provided (naturally or man-made) and approved by the Administrative Authority.
7
Water pipes crossing or adjacent to sewer or drainage piping constructed of clay or materials that are not approved for use within a building shall be laid a minimum of 12 inches (30.5 cm) from the sewer or drain pipe.
8
Measure the setback from the outside of the private sewage disposal system component to the top of the cut bank or ditch, or to the nearest sidewall of a culvert.
9
Measured from the edge of the driveway to the nearest edge of septic tank excavation. A properly reinforced septic tank and cover may be placed at any location relative to a driveway if access openings, risers, and covers carry the design load and are protected from inflow.
10
Setback may be increased due to soil loading and stability concerns.
11
5 feet (1.5 m) minimum unless other setback requirements govern.
Table I-2. Design liquid capacity (size) of septic tanks
|
No. of
Bedrooms
|
No. of
Occupants
|
No. of
Baths
|
Maximum
Fixture Count
|
Recommended
Septic Tank Size
in Gallons (L)
|
Minimum Septic
Tank Size in Gallons
(L) (+ or - 5%)
|
|
2
|
4
|
1
|
12
|
1000 (3785)
|
1000 (3785)
|
|
2
|
4
|
2
|
18
|
1000 (3785)
|
1000 (3785)
|
|
3
|
6
|
1
|
18
|
1250 (4731)
|
1000 (3785)
|
|
3
|
6
|
2
|
18
|
1250 (4731)
|
1000 (3785)
|
|
4
|
8
|
2
|
24
|
1500 (5678)
|
1250 (4731)
|
|
4
|
8
|
3
|
25
|
1500 (5678)
|
1250 (4731)
|
|
5
|
10
|
2
|
30
|
2000 (7570)
|
1500 (5678)
|
|
5
|
10
|
3
|
30
|
2000 (7570)
|
1500 (5678)
|
|
5
|
10
|
4
|
32
|
2000 (7570)
|
1500 (5678)
|
|
6
|
12
|
3
|
36
|
2500 (9463)
|
2000 (7570)
|
|
6
|
12
|
4
|
36
|
2500 (9463)
|
2000 (7570)
|
|
6
|
12
|
5
|
39
|
2500 (9463)
|
2000 (7570)
|
|
7
|
14
|
3
|
42
|
2500 (9463)
|
2000 (7570)
|
|
7
|
14
|
4
|
42
|
2500 (9463)
|
2000 (7570)
|
|
7
|
14
|
5
|
42
|
2500 (9463)
|
2000 (7570)
|
Table I-3. Estimated Waste/Sewage Flow Rates
Because of the many variables encountered, it is not possible to set absolute values for waste/sewage flow rates for all situations. The designer should evaluate each situation and, if figures in this table need modification, they should be made with the concurrence of the Administrative Authority.
|
Type of Occupancy
|
Gallons (Liters) Per Day
|
|
1. Airports
|
15 (56.7) per employee
5 (18.9) per passenger
|
|
2. Auto Washers
|
Per manufacturer's specification
|
|
3. Bowling Alleys (snack bar only)
|
75 (283.9) per lane
|
|
4. Camps
Campground with central comfort station
With flush toilets, no showers
Day camps (no meals served)
Summer and seasonal
|
35 (132.4) per person
25 (94.6) per person
15 (56.7) per person
50 (189.2) per person
|
|
5. Churches (Sanctuary)
With kitchen waste
|
5 (18.9) per seat
7 (26.4) per seat
|
|
6. Dance halls
|
5 (18.9) per person
|
|
7. Factories
No showers
With showers
Cafeteria, add
|
25 (94.6) per employee
35 (132.4) per employee
5 (18.9) per employee
|
|
8. Hospitals
Kitchen waste only
Laundry waste only
|
250 (946.3) per bed
25 (94.6) per bed
40 (151.4) per bed
|
|
9. Hotels
With kitchen
Without kitchen
|
60 (227.1) per bed (2 person)
50 (189.2) per bed (2 person)
|
|
10. Institutions (Resident)
|
75 (283.9) per person
|
|
Nursing home
Rest home
|
125 (473.1) per person
125 (473.1) per person
|
|
11. Laundries, self service (minimum 10 hours per day)
Commercial
|
50 (189.2) per wash cycle
Per manufacturer's specification
|
|
12. Motel
With kitchen
Without kitchen
|
60 (227.1) per bed (2 person)
50 (189.2) per bed (2 person)
|
|
13. Offices
|
20 (75.7) per employee
|
|
14. Parks
Mobile homes
Picnic parks (toilets only)
Recreational vehicles -
Without water or sewer hook-up
With water and sewer hook-up
|
250 (946.3) per parking space
20 (75.7) per parking space
75 (283.9) per parking space
100 (378.5) per parking space
|
|
15. Restaurants - cafeterias
Toilet
Kitchen waste
Garbage disposal
Cocktail lounge
Kitchen waste -
Disposal service
|
20 (75.7) per employee
7 (26.4) per customer
6 (22.7) per meal
1 (3.7) per meal
2 (7.5) per customer
2 (7.5) per meal
|
|
16. Schools - Staff and office
Elementary
Middle and high
With gym and showers, add
With cafeteria, add
Boarding, total waste
|
20 (75.7) per person
15 (56.7) per student
20 (75.7) per student
5 (18.9) per student
3 (11.3) per student
100 (378.5) per person
|
|
17. Service station, toilets
|
1000 (3785.4) for first bay
500 (1892.7) for each additional bay
|
|
18. Stores
Public restrooms, add
|
20 (75.7) per employee
1 per 10 sq. ft. of floor space
(3.79 per 9290.3 sq. cm of floor space)
|
|
19. Swimming pools, public
|
10 (37.8) per person
|
|
20. Theaters, auditoriums
Indoor
Drive-in
|
5 (18.9) per seat
10 (37.8) per space
|
|
21. Single Family Residential Dwellings
|
150 (567.7)
per bedroom or
25 (94.6)
per fixture unit whichever is greater
|
|
22. For structures and facilities not specifically addressed in the above table, flow rates available from other
standard books and literature may be approved.
|
(a) Recommended Design Criteria. The size of the sewage disposal system components, for uses other than a single family residential dwelling, is calculated as follows:
For waste/sewage flow, up to 3000 gallons/day (11,355 liters/day)
Design Flow = The total of the estimated flow rates from Table I-3
Septic tank size = design flow x 2.1.
(b) Also see Section I 3 of this appendix.
(c) Additional treatment of sewage is required if sewage quality exceeds 430 milligrams/liter for total suspended solids, 380 milligrams/liter for the five-day biochemical oxygen demand, 75 milligrams/liter for fats, oils, and greases, or the sewage includes wastes other than those originating from domestic toilet flushing, food preparation, non-occupational laundry, or personal hygiene, or wastes originating from an operation using any hazardous substance or creating a hazardous waste as defined in the statutes or rules of the Arizona Department of Environmental Quality.
Table I-4 (A). Soil Absorption Rate and Minimum Vertical Separation for Shallow Disposal Field Systems by Soil Evaluation Method
1
Instructions: Read questions in the following table beginning with row A. The first "yes" response from columns a or b determines the maximum soil absorption rate.
|
|
A
Soil Absorption Rate
in gallons per day (gpd)
per sq. ft.
liters per day
(lpd) sq. m
|
B
Soil Absorption Rate
in sq. ft. per 100 gallons
per day (gpd)
sq. m. per 100 liters per
day (lpd)
|
|
A. Is the horizon gravelly coarse sand or coarser?
|
0 (0)
|
0 (0)
|
|
B. Is the structure of the horizon moderate or
strongly platy?
|
0 (0)
|
0 (0)
|
|
C. Is the texture of the horizon sandy clay loam,
clay loam, silty clay loam, or finer and
structure weak platy?
|
0 (0)
|
0 (0)
|
|
D. Is the moist consistence stronger than firm or
any cemented class?
|
0 (0)
|
0 (0)
|
|
E. Is texture sandy clay, clay, or silty clay of high
clay content and structure massive or weak?
|
0 (0)
|
0 (0)
|
|
F. Is texture sandy clay loam, clay loam, silty clay
loam, or silty loam and structure massive?
|
0 (0)
|
0 (0)
|
|
G. Is the texture of the horizon loam or sandy
loam and the soil structure massive?
|
.20 (8.15)
|
500 (12.3)
|
|
H. Is texture sandy clay, clay, or silty clay of low
clay content and the structure moderate or strong?
|
.20 (8.15)
|
500 (12.3)
|
|
I. Is texture sandy clay loam, clay loam, or silty
clay loam and structure weak?
|
.20 (8.15)
|
500 (12.3)
|
|
J. Is texture sandy clay loam, clay loam, or silty
clay loam and structure moderate or strong?
|
.40 (16.30)
|
250 (6.1)
|
|
K. Is texture sandy loam, loam, or silty loam and
structure weak?
|
.40 (16.30)
|
250 (6.1)
|
|
L. Is texture sandy loam, loam, silt loam and
structure moderate or strong?
|
.60 (24.45)
|
166.7 (4.1)
|
|
M. Is texture fine sand, very fine sand, loamy fine
sand, or loamy very fine sand?
|
.40 (16.30)
|
250 (6.1)
|
|
N. Is texture loamy sand or sand?
|
.80 (32.59)
|
125 (3.1)
|
|
O. Is texture coarse sand?
2
|
1.20 (48.89)
|
83.3 (2.0)
|
Notes:
1
Shallow trench and bed systems are less than 5 feet (1.52 m) deep and shall have a minimum vertical separation of 4 feet (1.22 m) to rock, fractured rock, soils with greater than 50% rock fragments and a 5 foot (1.52 m) zone of unsaturated soil to groundwater.
2
Shallow trench and bed systems are less than 5 feet (1.52 m) deep and shall have a minimum vertical separation of 10 feet (3.04 m) to rock, fractured rock, soils with greater than 50% rock fragments and a 10 foot (3.04 m) zone of unsaturated soil to groundwater.
Example:
Three-bedroom dwelling, wastewater flow rate = 450 gpd (1,703 lpd), soil texture is loamy sand (N).
Using Column A - Effective Area = Divide the flow rate (450 gpd) (1,703 lpd) by the soil application rate of 0.8 gpd/sq. ft. (32.6 lpd/sq. m.)
Effective Area = 450/0.8 = 562.5 sq. ft. (1,703/32.6 = 52.3 sq. m.).
Using Column B - Effective Area = Multiply the flow rate (450 gpd) (1,703 lpd) by the soil application rate of 125 sq. ft./100 gpd (3.1 sq. m./100 lpd)
Effective Area = 450x125/100 = 562.5 sq. ft. (3.1 x 1,703/100 = 52.3 sq. m.).
Table I-4 (B). Soil Absorption Rate and Minimum Vertical Separation for Deep Disposal Field Systems by Soil Evaluation Method
1
Instructions: Read questions in the following table beginning with row A. The first "yes" response from columns A or B determines the maximum soil absorption rate.
|
|
A
Soil Absorption Rate
in gallons per day (gpd)
per sq. ft.
liters per day
(lpd) sq. m
|
B
Soil Absorption Rate
in sq. ft. per 100 gallons
per day (gpd)
sq. m. per 100 liters per
day (lpd)
|
|
A. Is the horizon gravelly coarse sand or coarser?
|
0 (0)
|
0 (0)
|
|
B. Is the structure of the horizon moderate or
strongly platy?
|
0 (0)
|
0 (0)
|
|
C. Is the texture of the horizon sandy clay loam, clay
loam, silty clay loam, or finer and structure weak
platy?
|
0 (0)
|
0 (0)
|
|
D. Is the moist consistence stronger than firm or any
cemented class?
|
0 (0)
|
0 (0)
|
|
E. Is texture sandy clay, clay, or silty clay of high clay
content and structure massive or weak?
|
0 (0)
|
0 (0)
|
|
F. Is texture sandy clay loam, clay loam, silty clay loam,
or silty loam and structure massive?
|
0 (0)
|
0 (0)
|
|
G. Is the texture of the horizon loam or sandy loam and
the soil structure massive?
|
.13 (5.3)
|
769 (18.9)
|
|
H. Is texture sandy clay, clay, or silty clay of low clay
content and the structure moderate or strong?
|
.13 (5.3)
|
769 (18.9)
|
|
I. Is texture sandy clay loam, clay loam, or silty clay
loam and structure weak?
|
.13 (5.3)
|
769 (18.9)
|
|
J. Is texture sandy clay loam, clay loam, or silty clay
loam and structure moderate or strong?
|
.27 (11.0)
|
370.4 (9.1)
|
|
K. Is texture sandy loam, loam, or silty loam and structure
weak?
|
.27 (11.0)
|
370.4 (9.1)
|
|
L. Is texture sandy loam, loam, silt loam and structure
moderate or strong?
|
.40 (16.3)
|
250 (6.1)
|
|
M. Is texture fine sand, very fine sand, loamy fine sand, or
loamy very fine sand?
|
.27 (11.0)
|
370.4 (9.1)
|
|
N. Is texture loamy sand or sand?
|
.53 (21.6)
|
188.7 (4.6)
|
|
O. Is texture coarse sand?
|
0 (0)
|
0 (0)
|
Notes:
1
Deep trench systems are greater than or equal to 5 feet (1.52 m) and less than 10 feet (3.0 m) deep and shall have a minimum vertical separation of 5 feet (1.52 m) to rock, fractured rock, soils with greater than 50% rock fragments and a 5 foot (1.52 m) zone of unsaturated soil to groundwater.
Example:
Three-bedroom dwelling, wastewater flow rate = 450 gpd (1,703 lpd), soil texture is loamy sand (N).
Using Column A - Effective Area = Divide the flow rate (450 gpd) (1,703 lpd) by the soil application rate of 0.53 gpd/sq. ft(21.6 lpd)
Effective Area = 450/0.53 = 849 sq. ft. (1,703/21.6 = 78.8 sq. m.).
Using Column B - Effective Area = Multiply the flow rate (450 gpd) (1,703 lpd) by the soil application rate of 188.7 sq. ft./100 gpd(4.6 sq. m./100 lpd)
Effective Area = 450x188.7/100 = 849 sq. ft. (4.6 x1,703/100) = 78.3 sq. m.).
Table I-5. Soil Absorption Rate and Minimum Vertical Separation for Seepage Pits
|
Soil
Characteristics
|
Percolation
Test Rate Range
|
Maximum Soil
Absorption Rate
|
Minimum Vertical Separation to
Groundwater
|
|
|
|
|
Gravel
Seepage Pit
|
Lined
Seepage Pit
|
|
|
minutes per inch
(minutes per cm)
|
gpd/sq. ft. (lpd/sq. m.)
|
ft (m)
|
ft (m)
|
|
Gravelly Coarse
Sands
|
less than
1.00 (0.39)
|
greater than 1.20 (48.9)
NOT PERMITTED
|
-
|
-
|
|
Coarse to Medium
to Fine Sands
|
1.00 to less than
2.00
(0.39 to less than
0.78)
|
1.20 (48.9)
|
60 (18.3)
|
60 (18.3)
|
|
Medium to Fine Sands
and Silty Sands
|
2.00 to less than
3.00 (0.78 to less
than 1.18)
3.00 to less than
4.00 (1.18 to less
than 1.57)
4.00 to less than
5.00 (1.57 to less
than 1.96)
5.00 to less than
6.00 (1.96 to less
than 2.75)
|
1.10 (44.8)
1.00 (40.7)
0.90 (36.7)
0.75 (30.6)
|
60 (18.3)
60 (18.3)
60 (18.3)
60 (18.3)
|
60 (18.3)
60 (18.3)
60 (18.3)
60 (18.3)
|
|
Fine to Very Fine
sands and Loamy Sands
|
7.00 to less than
10.00 (2.75 to less
than 3.93)
|
0.63 (25.7)
|
25 (7.6)
|
25 (7.6)
|
|
Sandy to Silty Loams,
loam
|
10.00 to less than
15.00 (25.4 to less
than 38.1)
15.00 to less than
20.00 (38.1 to less
than 50.8)
20.00 to less than
25.00 (50.8 to less
than 63.5)
25.00 to less than
30.00 (63.5 to less
than 76.2)
|
0.50 (20.4)
0.44 (17.9)
0.40 (16.3)
0.36 (14.7)
|
25 (7.6)
25 (7.6)
25 (7.6)
25 (7.6)
|
25 (7.6)
25 (7.6)
25 (7.6)
25 (7.6)
|
|
Strongly Structured Loams and Clayey Soils
|
greater than
30.00 (76.2)
|
less than .36
NOT PERMITTED
|
-
|
-
|
(a) Seepage pits shall be bored 5 feet (1.5 m) deeper than the proposed pit depth to verify underlying soil characteristics, unless water table evidence or bedrock is encountered sooner. The 5 feet (1.5 m) of overdrill shall then be backfilled with low permeability drill cuttings or other suitable material.
(b) Seepage pits that terminate in gravelly, coarse sand stratas shall be backfilled 5 feet (1.5 m) above the beginning of such strata with low permeability drill cuttings or other suitable material.
Table I-6. Seepage Pit Effective Absorption Area
|
Effective Strata Depth Below
Flow Line
|
Seepage Pit Effective
Absorption Area, sq. ft. (sq. m.)
|
|
|
Diameter of Seepage Pit
|
|
ft (m)
|
4 ft (1.2 m)
|
5 ft (1.5 m)
|
6 ft (1.8 m)
|
|
1 (0.3)
|
13 (1.2)
|
16 (1.5)
|
19 (1.8)
|
|
2 (0.6)
|
25 (2.3)
|
31 (2.9)
|
38 (3.5)
|
|
3 (0.9)
|
38 (3.5)
|
47 (4.4)
|
57 (5.3)
|
|
4 (1.2)
|
50 (4.6)
|
63 (5.9)
|
75 (7.0)
|
|
5 (1.5)
|
63 (5.9)
|
79 (7.3)
|
94 (8.7)
|
|
6 (1.8)
|
75 (7.0)
|
94 (8.7)
|
113 (10.5)
|
|
7 (2.1)
|
88 (8.2)
|
110 (10.2)
|
132 (12.3)
|
|
8 (2.4)
|
100 (9.3)
|
126 (11.7)
|
151 (14.0)
|
|
9 (2.7)
|
113 (10.5)
|
141 (13.1)
|
170 (15.8)
|
|
10 (3.0)
|
126 (11.7)
|
157 (14.6)
|
189 (17.6)
|
|
20 (6.l)
|
251 (23.3)
|
314 (29.2)
|
377 (35.0)
|
|
30 (9.1)
|
377 (35.0)
|
471 (43.8)
|
566 (52.6)
|
|
40 (12.2)
|
502 (46.6)
|
628 (58.3)
|
754 (70.0)
|
|
50 (15.2)
|
628 (58.3)
|
785 (72.9)
|
943 (87.6)
|
(a) Minimum Effective Depth of Pit = 10 ft. (3.0 m).
(b) Sufficient area shall be provided for at least two bedrooms.
(c) Effective absorption surface for seepage pits includes sidewall areas only.
Table I-7. Soil Absorption Rate and Minimum Vertical Separation for Disposal Field Systems by Percolation Test Results
|
Percolation Rate from
Percolation Test
minutes per in (minutes
per cm.)
|
Shallow Disposal Field
System
2
Soil Absorption
Rate
gpd/sq. ft. (lpd/sq. m.)
|
Deep Disposal Field System
3
Soil Absorption Rate
gpd/sq. ft. (lpd/sq. m.)
|
Minimum Vertical
Separation
4
ft (m)
|
|
less than 1.00
|
Note
1
|
Note
1
|
Note
1
|
|
l.00 to less than 3.00 (1.18)
|
1.20 (48.9)
|
0.93 (37.9)
|
40.0 (12.2)
|
|
3.00 (1.18)
|
1.10 (44.8)
|
0.73 (29.7)
|
10.0 (3.0)
|
|
4.00 (1.57)
|
1.00 (40.7)
|
0.67 (27.3)
|
10.0 (3.0)
|
|
5.00 (1.97)
|
0.90 (36.7)
|
0.60 (24.4)
|
10.0 (3.0)
|
|
7.00 (2.76)
|
0.75 (30.6)
|
0.50 (20.4)
|
10.0 (3.0)
|
|
10.0 (3.94)
|
0.63 (25.7)
|
0.42 (17.1)
|
10.0 (3.0)
|
|
15.0 (5.91)
|
0.50 (20.4)
|
0.33 (13.4)
|
5.0 (1.5)
|
|
20.0 (7.87)
|
0.44 (17.9)
|
0.29 (11.8)
|
5.0 (1.5)
|
|
25.0 (9.84)
|
0.40 (16.3)
|
0.27 (11.0)
|
5.0 (1.5)
|
|
30.0 (11.81)
|
0.36 (14.7)
|
0.24 (9.8)
|
5.0 (1.5)
|
|
35.0 (13.78)
|
0.33 (13.4)
|
0.22 (9.0)
|
5.0 (1.5)
|
|
40.0 (15.75)
|
0.31 (12.6)
|
0.21 (8.6)
|
5.0 (1.5)
|
|
45.0 (17.72)
|
0.29 (11.8)
|
0.20 (8.1)
|
5.0 (1.5)
|
|
50.0 (19.68)
|
0.28 (11.4)
|
0.19 (7.7)
|
5.0 (1.5)
|
|
55.0 (21.65)
|
0.27 (11.0)
|
0.18 (7.3)
|
5.0 (1.5)
|
|
more than 55.0 to 60.0 (21.65 to 23.62)
|
0.25 (10.2)
|
0.17 (6.9)
|
5.0 (1.5)
|
|
more than 60.0 to 120 (23.62 to 47.24)
|
0.20 (8.1)
|
0.13 (5.3)
|
5.0 (1.5)
|
Notes:
1
Not permitted for septic tank effluent.
2
Depth of bottom of disposal field below finished grade of soil is less than 5.00 feet (1.5 m).
3
Depth of bottom of disposal field below finished grade of soil is 5.00 feet (1.5 m) or greater.
4
Minimum vertical distance required for achieving unsaturated flow is measured from the bottom of a constructed disposal field to the nearest restrictive soil condition including, but not limited to, the seasonal high water table capillary fringe, impermeable layer, rock, fractured rock, soils with greater than 50% rock fragments, and unacceptable soil.
Historical Note
New Section made by final rulemaking at 9 A.A.R. 1189, effective May 18, 2003 (Supp. 03-1).
R4-48-147. Installation Standard for PEX-AL-PEX and PE-AL-PE
The Uniform Plumbing Code incorporated in R4-48-102(A) is modified as follows:
Add a new installation standard for PEX-AL-PEX and PE-AL-PE:
COMPOSITE PEX-AL-PEX HOT AND PE-AL-PE COLD
WATER-DISTRIBUTION SYSTEMS
This Standard shall govern the installation of composite piping in potable hot and cold water distribution systems within and under buildings and shall apply only to PEX-AL-PEX and PE-AL-PE piping meeting the requirements of ASTM F 1281-02e1 and ASTM F 1282-02e1. Installation, materials, and inspection shall comply with the 1994 edition of the Uniform Plumbing Code as modified by this Chapter, published by the International Association of Plumbing and Mechanical Officials, and shall also comply with this standard and manufacturer's installation recommendations.
NOTE: The following sections of the Uniform Plumbing Code shall apply to composite PEX-AL-PEX and PE-AL-PE piping.
301.0 Materials - Standards and Alternates
310.0 Workmanship
313.0 Protection of Piping, Materials, and Structures
314.0 Hangers and Supports
316.1.4 Flexible Compression Factory Fabricated Joints
316.2.3 Plastic Pipe to Other Materials
606.0 Joints and Connections
608.0 Water Pressure, Pressure Regulators, and Pressure Relief Valves
609.0 Installation, Unions, and Location
610.0 Size of Potable Water Piping
Note: The following clauses are the Installation Standard. Note that the Section numbers 301, 313, 314, 316, 606, 608, 609, and 610 relate to the sections of the UPC but the specific clause numbers of this Installation Standard are not intended to match the UPC.
Chapter 2 DEFINITIONS
ASTM American Society for Testing and Materials
IAPMO International Association of Plumbing and Mechanical Officials
PEX-AL-PEX Crosslinked Polyethylene-Aluminum-Crosslinked Polyethylene
PE-AL-PE Polyethylene-Aluminum-Polyethylene
UPC Uniform Plumbing Code as published by IAPMO
301.0 Materials - Standards and Alternates
301.1 Minimum Standards
301.1.1 Materials - Materials shall comply with the following requirements:
Materials ASTM Standard
Crosslinked Polyethylene-
Aluminum-Crosslinked
Polyethylene (PEX-AL-PEX) F 1281-02e1
Polyethylene-Aluminum-
Polyethylene (PE-AL-PE) F 1282-02e1
Metal Insert Fittings for
PEX-AL-PEX and PE-AL-PE
composite pipe F 1974-01e1
301.1.1.1 Piping - PEX-AL-PEX composite pipe shall comply with ASTM F 1281-02el.
PE-AL-PE composite pipe shall comply with ASTM F 1282-02e1.
301.1.1.2 Fittings - Fittings shall be metal insert type and shall comply with ASTM F 1974-01e1.
Manufacturers of fittings shall recommend assembly procedures. Fittings are limited to the following types:
(a) Insert fittings or compression type fittings,
(b) Special listed fittings of other types - Connections to galvanized pipe or fittings shall be specifically designed for that purpose.
301.1.2 Markings
301.1.2.1 Piping - Composite piping shall be legibly marked at intervals of not more than 5' (1.5m) with at least the following:
(a) Manufacturer's name or trademark;
(b) ASTM F 1281-02e1(PEX-AL-PEX) or F 1282-02e1(PE-AL-PE);
(c) Piping size;
(d) Material type - PEX-AL-PEX or PE-AL-PE;
(e) Pressure ratings at 125 psi (862 kPa) at 180° F (82° C) (PEX-AL-PEX)* or, 200psi (1380 kPa) at 73° F (23° C) (PE-AL-PE)*
(f) Mark of an acceptable certification agency;
(g) Manufacturer's date and material code
* The elevated temperature and pressure ratings for PEX-AL-PEX and PE-AL-PE in accordance with ASTM F1281-02e1 and ASTM F1282-02e1 are:
|
PEX-AL-PEX
(orange colored)
|
200 psi at
73° F
|
125 psi at 180° F
|
|
PE-AL-PE
(blue colored)
|
200 psi at
73° F
|
160 psi at 140° F
|
301.1.2.2 Fittings - Fittings shall be marked with at least the following:
(a) Manufacturer's name or trademark or other acceptable markings; and
(b) Fittings shall be labeled with the mark of an acceptable certification agency.
(c) If size permits, ASTM F1974-01e1.
301.1.2.3 Position of Markings - When practical, markings shall be visible for inspection. Markings shall be visible prior to installation.
313.0 Protection of Piping, Materials, and Structures
313.1 Abrasion - Piping passing through metallic studs, joists, or hollow masonry walls shall be protected from abrasion or sharp edges by elastomeric or plastic sleeves, grommets, conical shaped punch holes or other approved means.
313.2 Puncture - Steel plate protection, minimum 18 gauge, shall be installed when the piping is within 1" (25 mm) of the nailing surface.
313.3 Exposed Piping
313.3.1 General - Where exposed piping may be subjected to mechanical damage it shall be protected.
313.4 Freezing - In areas where the system must be drained to protect the system from freezing, horizontal lines shall be graded to drain.
313.5 Storage - Piping shall be stored in a way to protect the system from mechanical damage (slitting, puncturing, etc.). Piping should be stored undercover to keep it clean and avoid long term exposure to sunlight. Consult piping manufacturer for recommended limits for outside storage.
313.6 Thermal Expansion
313.6.1 General - The linear expansion rate for PEX-AL-PEX and PE-AL-PE is 1.56" (39.6 mm) per 100' (30m) of tube per 100° F (55° C) change in temperature. No accommodation for thermal expansion is required.
313.6.2 Clearance - Bored holes and sleeves shall provide adequate clearance between the piping and structure to allow for free longitudinal movement.
314.0 Hangers and Supports
314.1 Vertical Piping - Vertical piping shall be supported at every floor. Piping shall have a mid-story guide.
314.2 Horizontal Piping - Horizontal piping shall be supported according to the following Table A.
Table A. Support Spacing
|
Nominal Diameter
|
Spacing
|
|
1/2", 3/4", and 1"
|
8' 2" (2489 mm)
|
314.3 Hangers and Anchors - Piping shall not be anchored rigidly to a support; but shall be secured with hangers or straps that provide for a degree of movement and that prevent damage to the piping. Do not use hangers or straps with sharp or abrasive edges. Do not use hangers that pinch the piping.
314.4 Inspection and Testing
A. Inspection - All piping shall be properly seated on to the fitting per the manufacturer instructions. Buckled, gouged or obviously damaged pipe shall not be used. Consult manufacturer recommendations for repair procedures.
B. Testing - Upon completion of a section or of the entire hot and cold water supply system it shall be tested and proved tight under a water pressure or air test not less than the working pressure under which it is to be used. The water used for tests shall be obtained from a potable source. The system shall withstand the test without leaking for a period of not less than 15 minutes.
316.0 Joints and Connections
316.1 Joints and Connections
316.1.1 Procedure - Piping shall be cut with a pipe cutter designed specifically for composite pipe. Piping shall be cut square, i.e. perpendicular to the length. If other cutting methods are used, care shall be taken to remove any excess material, flashing, or burrs.
316.1.2 Tools - The manufacturer's recommend fitting tool shall be used with the composite insert fitting systems. For specific procedures, follow the manufacturer's recommendations.
316.2 Special Joints
316.2.1 Fittings - Transitions for composite piping to metal piping or valves shall be made only with transition fittings intended for that purpose.
606.0 Joints and Connections
606.1 Joints - Joints shall not be allowed in piping installed in or under a concrete slab resting on grade unless for repair within a building structure. All repair joints shall be properly protected with a heat shrink sleeve. All slab penetrations shall be sleeved.
608.0 Water Pressure, Pressure Regulators, and Pressure Relief Valves
608.1 PEX-AL-PEX Piping - PEX-AL-PEX piping used for temperature or pressure relief valve drain lines shall be graded to the outlet end and shall be supported at a maximum of 8' 2" (2489 mm) interval horizontally. Vertical piping shall be supported at every floor. Vertical piping shall have a mid-story guide.
609.0 Installation, Unions, and Location
609.1 Bends - Piping shall be installed by bending the composite pipe by hand to a minimum radius of five times the nominal pipe diameter. External bend supports or sleeves are not required as the composite piping is rigid after bending.
609.2 Damage - Kinked, buckled, gouged, or other obviously damaged piping shall not be used.
609.3 Finish Nipples - Finish nipples shall be connected to drop ear fittings to prevent rotation. Finish nipples shall not be PEX.
609.4 Hose Bibs - The piping directly connected to any hose bib shall be so anchored that the load on the hose bib will not strain the composite piping.
609.5 Heated Joints - An open flame shall not be applied to PEX-AL-PEX or PE-AL-PE piping when brazing, soldering, or welding joints.
609.6 Working Pressure and Temperature - Long-term working pressures for the PEX-AL-PEX shall not exceed a maximum of 115 psi (793 kPa) and the long-term working temperature shall not exceed 210° F (99° C). Long-term working pressures for the PE-AL-PE shall not exceed a maximum of 160 psi (1103.2 kPa) and the long-term working temperature shall not exceed 140° F (60° C).
609.7 Exposure to Sunlight - Only UV stabilized composite piping shall be subjected to direct sunlight after installation and shall be installed on the surface of the building. Kitec pipe contains an ultraviolet (UV) inhibitor to withstand limited exposure to UV light. Manufacturer recommends placing the unused portion of a Kitec coil back in the product's box rather than storing in the sunlight while not in use.
609.8 Water Heater Connections - PEX-AL-PEX or PE-AL-PE piping shall not be installed within the first 18" (457 mm) of piping connected to a water heater.
609.10 Water Hammer Arrestors - A composite hot water system shall withstand repeated pressure surges, well in excess of its rated pressure. The Arizona Uniform Plumbing Code requires a means of attenuating water hammer. Consequently water hammer arrestors may be advisable when solenoid valves or other quick closing devices are used in the system. In designing for these situations, it is advisable to consult the pipe or fittings manufacturer for recommended surge pressure limits. Water hammer and surge pressure calculations are reviewed in Chapter 7, AWWA Manual M-11.
610.1 Size of Potable Water Piping
610.1.1 Method - Piping shall be sized in accordance with a Arizona Uniform Plumbing Code Section 610.0.
When a Arizona Uniform Plumbing Code Appendix A is applicable, use Table B.
Add equivalent lengths from Table C when determining developed length.
Maximum velocities through PEX-AL-PEX and PE-AL-PE copper alloy fittings shall be limited to 8' per second (fps) (2.4 mps) in cold water and 5' per second (fps) (1.52 mps) in hot water.
Table B. Head Loss vs. Flow Rate
|
Flow Rate U.S. GPM
|
1/2"
|
3/4"
|
1"
|
|
|
Head Loss
Psi/c.ft.
|
Velocity
Ft./s
|
Head Loss
Psi/c.ft.
|
Velocity
Ft./s
|
Head Loss
Psi/c.ft.
|
Velocity
Ft./s
|
|
0.1
|
0.02
|
0.2
|
0.002
|
0.07
|
0.001
|
0.04
|
|
0.2
|
0.1
|
0.4
|
0.01
|
0.1
|
0.002
|
0.08
|
|
0.3
|
0.2
|
0.6
|
0.02
|
0.2
|
0.005
|
0.1
|
|
0.4
|
0.3
|
0.7
|
0.03
|
0.3
|
0.009
|
0.2
|
|
0.5
|
0.5
|
0.9
|
0.04
|
0.3
|
0.01
|
0.2
|
|
0.6
|
0.6
|
1.1
|
0.05
|
0.4
|
0.02
|
0.3
|
|
0.7
|
0.9
|
1.3
|
0.07
|
0.5
|
0.02
|
0.3
|
|
0.8
|
1.1
|
1.5
|
0.09
|
0.5
|
0.03
|
0.3
|
|
0.9
|
1.4
|
1.7
|
0.1
|
0.6
|
0.04
|
0.4
|
|
1.0
|
1.6
|
1.8
|
0.1
|
0.7
|
0.05
|
0.4
|
|
2.0
|
5.9
|
3.7
|
0.5
|
1.3
|
0.2
|
0.9
|
|
3.0
|
12.5
|
5.5
|
1.0
|
2.0
|
0.4
|
1.3
|
|
4.0
|
21.3
|
7.3
|
1.8
|
2.6
|
0.6
|
1.7
|
|
5.0
|
|
|
2.7
|
3.3
|
0.9
|
2.1
|
|
6.0
|
|
|
3.8
|
4.0
|
1.3
|
2.5
|
|
7.0
|
|
|
5.0
|
4.6
|
1.7
|
3.0
|
|
8.0
|
|
|
6.4
|
5.3
|
2.2
|
3.4
|
|
9.0
|
|
|
8.0
|
5.9
|
2.7
|
3.8
|
|
10.0
|
|
|
9.7
|
6.6
|
3.3
|
4.2
|
|
11.0
|
|
|
11.6
|
7.2
|
3.9
|
4.6
|
|
12.0
|
|
|
13.6
|
7.9
|
4.6
|
5.0
|
|
13.0
|
|
|
|
|
5.3
|
5.5
|
|
14.0
|
|
|
|
|
6.1
|
5.9
|
|
15.0
|
|
|
|
|
6.9
|
6.3
|
|
16.0
|
|
|
|
|
7.8
|
6.3
|
|
17.0
|
|
|
|
|
8.7
|
6.7
|
|
18.0
|
|
|
|
|
9.7
|
7.1
|
|
19.0
|
|
|
|
|
10.7
|
7.6
|
|
20.0
|
|
|
|
|
11.8
|
8.0
|
Table C. Developed Length
|
Sizes, Inches
|
Type of Fittings
|
Equivalent Length of
Pipe (Feet)
|
|
1/2
|
Couplings
Adapters
Elbows
Tees (Branch Flow)
Tees (On the Run)
|
2
2
7.5
8
2.5
|
|
3/4
|
Couplings
Adapters
Elbows
Tees (Branch Flow)
Tees (On the Run)
|
2
2
8.5
10.5
2.5
|
|
1
|
Couplings
Adapters
Elbows
Tees (Branch Flow)
Tees (On the Run)
|
2
2
9
11
2.5
|
