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Section 8 of the septic design regulations discusses the means of disposition of septic effluent using a conventional septic leach field (drainfield, absorption bed are synonyms). Distances from the leach field to other site features, design criteria based on soil percolation test results, absorption trench length requirements, and materials to be used are all discussed.

This document uses the New York State wastewater treatment standard for individual household septic systems (Appendix 75-A) to provide an example of state regulated design and installation of both conventional tank and leach field septic systems and alternative septic system designs, including raised septic systems, septic mound systems, intermittent sand filter septic systems, and evaportion-transpiration septic systems.

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Section 75-A.8 Subsurface treatment - disposal of septic effluent using a conventional septic leach field or absorption field

Effective Date: 12/01/90

(a) General Information

All effluent from septic tanks or aerobic tanks shall be discharged to a subsurface treatment system. Surface discharge of septic tank or aerobic unit effluent shall not be approved by the Department of Health or a local health department acting as its agent.

(b) Absorption Field Systems - Conventional Septic Leach Fields

[DF NOTE: This section discusses the design requirements for septic absorption fields, also called leach fields, drain fields, drainfields, or conventional soil absorption systems.]

(1) Site requirements for Septic Drainfields

(i) The minimum distances that absorption fields shall be separated from other facilities are shown in Figure 1 and Table 2.

(ii) A minimum of four feet of useable soil shall exist above bedrock and groundwater with a minimum separation of two feet to the lowest part of any trench.

(iii) Absorption fields shall not be built under driveways, parts of buildings or under above-ground swimming pools or other areas subject to heavy loading. Surface waters shall be diverted from the vicinity of the system.

(2) Design criteria for Septic Drainfields

(i) The required length of absorption trench is determined from Table 4A based upon the percolation test results and confirmed by the soil evaluation. The maximum trench width for design purposes shall be 24 inches. Only 24 inches shall be allowed for absorption area calculations. Where trenches exceed 24 inches in width, calculations of absorptive area shall be based on a width of 24 inches.

(ii) Adjacent trenches shall be separated by at least four feet of undisturbed soil. Individual trenches shall be constructed parallel to the ground contours with trench bottoms as near level as possible. They need not be perfectly straight but abrupt changes in direction shall be avoided.

(3) Materials used for Septic Drainfields

(i) Perforated distributor pipe shall be used in the trenches. Solid (non-perforated) pipe shall be used between the distribution box and the trenches. Perforated pipe shall be made of rigid or corrugated plastic and be labeled as fully meeting ASTM standards for use in septic systems. Corrugated plastic pipe delivered in coils is not to be used unless provision is made to prevent the recoiling or movement of the pipe after installation.

(ii) Aggregate shall mean washed gravel or crushed stone 3/4 - 1 1/2 inches in diameter. Larger diameter material or finer substances and run-of-bank gravel are unacceptable.

(iii) The aggregate shall be covered with a material that prevents soil from entering the aggregate after backfilling, yet must permit air and moisture to pass through. The preferred material for covering the aggregate is a permeable geotextile. Untreated building paper or a four inch layer of hay or straw is acceptable. Polyethylene and treated building paper are relatively impervious and shall not be used.

(4) Construction of Septic Drainfields

(i) Trench locations and depths should be marked by stakes before the trenches are excavated. The natural surface shall not be significantly disturbed. If the site is re graded or similarly disturbed, the soil shall be allowed to stabilize and new percolation tests conducted.

(ii) The trench depth shall be as shallow as possible, but not less than 18 inches. At least six inches of aggregate is placed below the distribution line and two inches above the line. The earth cover over the aggregate should not exceed 12 inches in order to enhance natural aeration and nitrogen uptake by plant life. Trenches shall be excavated to design depth with bottoms practically level. Heavy equipment shall be kept away from the field because the weight may permanently alter soil characteristics due to compaction, cause trench cave-ins, and/or mis-align and break pipe.

(iii) Trench bottoms are to be raked and immediately covered with at least six inches of aggregate.

(iv) Any smeared surfaces on the trench walls are to be raked. Distributor lines are carefully placed on the aggregate and covered with aggregate to a depth of at least two inches over the top of the pipe. Additional aggregate may be required to bring the top of the aggregate to within six to 12 inches of the surface.

(v) In gravity distribution systems, the pipe shall be carefully sloped at between 1/16 inch and 1/32 inch per foot. Grades shall be determined by an engineer's level, transit or carpenter's level.

(vi) After the upper aggregate is placed, the geotextile, untreated building paper, hay or straw is to be immediately installed and the trench backfilled with native soil. If the trenches cannot be immediately backfilled, they should be temporarily covered with an impervious material such as treated building paper to prevent sidewall collapse and siltation into the aggregate.

(vii) The earth backfill is to be mounded slightly above the original ground level to allow for settling and after settlement the entire area should be graded without the use of heavy equipment and seeded with grass.

(c) Gravelless Septic Absorption Systems

(1) In one type of system, a large diameter corrugated plastic pipe (eight inches or greater in diameter) surrounded by a hydrophilic geotextile is installed in an excavated trench using only the original soil as backfill. Other systems utilizing products such as galleys, flow diffusers or leaching chambers can be installed without aggregate backfill. One linear foot of these products shall be equivalent to one linear foot of conventional (24 inch wide) absorption trench.

(2) Site requirements for gravelless septic absorption systems

These systems shall be used on sites that have been classified as having a design percolation rate of one to 45 minutes per inch, and meet the vertical and horizontal separation distances in Table 2 which is shown in 75-A.4 Soil and site appraisal for Septic Systems.

(3) Design criteria for gravelless septic absorption systems

The local health department having jurisdiction shall be contacted prior to construction regarding the acceptability of specific products for use as a gravelless distribution system.

(4) Construction of gravelless septic absorption systems

Gravelless distribution systems shall be installed in conformance with the manufacturer's instructions because of the proprietary design of some products.

(d) Deep Septic Absorption Trench Systems

(1) Site Requirements for deep trench septic systems

These are used on sites where an useable layer of soil is overlaid by three to five feet of impermeable soil.

(2) Design Criteria for deep trench septic systems

(i) There shall be at least four feet of useable solid beneath the impermeable layer.

(ii) The required length of absorption trench is determined from Table 4A based upon percolation tests conducted in the underlying soil.

(3) Construction specifications for deep trench septic absorption systems

(i) Trenches are excavated at least two feet into the useable layer and backfilled with aggregate or coarse sandy material containing a low percentage of fines more permeable than the underlying material to a level 30 inches below the original ground surface.

(ii) An absorption trench system as described in Section 75-A.8(b) is constructed in the upper 30 inches of the excavation.

(e) Shallow Septic System Absorption Trenches

(1) Site Requirements for shallow septic system absorption trenches

These systems are used where there is at least two feet but less than four feet of useable soil and/or separation to boundary conditions.

(2) Design criteria for shallow septic absorption trenches

(i) A minimum two foot separation must be maintained between the bottom of each trench and all boundary conditions.

(ii) The bottom of each trench must not be above the original ground surface.

(iii) Material of the same permeability as the underlying original soil shall be used as fill material. The depth of the fill shall not be greater than 30 inches above the original ground elevation.

(iv) An absorption trench system as described in Section 75-A.8(b) is designed using the percolation of the underlying original soil.

(3) Construction of Shallow Septic Absorption Trenches

(i) Heavy equipment shall be kept out of the absorption area.

(ii) Fill material is carefully placed within the absorption area.

(iii) The edge of the fill material shall be tapered at a slope of no greater than one vertical to three horizontal. On sloped sites a diversion ditch shall be placed on the uphill side to prevent runoff from entering the fill.

(iv) The absorption trench system is constructed in the fill material, extending into the existing natural soil.

(f) Cut and Fill Septic Systems

(1) A cut and fill septic system is an absorption trench system installed on sites where impermeable soil overlays a permeable soil.

(2) Site Requirements for cut and fill septic systems

Cut and fill septic systems may be used where all the following conditions are found:

(i) A soil with a percolation rate slower than 60 minutes per inch, such as clay or clay loam, overlays a useable soil with a percolation rate faster than 60 minutes per inch;

(ii) At least three feet of useable soil is available beneath the tight soil;

(iii) All minimum vertical and horizontal separation distances can be maintained as described in Table 2.

(3) Design criteria for cut and fill septic systems

(i) It shall provide for the removal of the overlaying unusable soil and replacement by soil having a percolation rate comparable with the underlying soil;

(ii) An absorption trench system is designed as described in Section 75-A.8(b).

(iii) The required length of absorption trench is based upon the percolation of the underlying soil or the fill material, whichever has the slower percolation (lower permeability).

(4) Construction of cut and fill septic systems

(i) The area excavated and filled must provide at least a five foot buffer in each direction beyond the trenches.

(ii) The material placed above the trenches shall have a percolation rate faster than 60 minutes per inch.

(iii) Original surface material shall not be used as backfill above the trenches.

(iv) The surface area of the fill system must be mounded and graded to enhance the runoff of rainwater from the system and seeded to grass.

(g) Absorption Bed Septic Systems

(1) General

An absorption bed system operates on a principal similar to the absorption trench except that several laterals, rather than just one, are installed in a single excavation. This reduces the effective sidewall infiltration area per linear foot of lateral or leach line.

(2) Site Requirements for absorption bed septic system

(i) A bed system may be built in soils with a percolation rate between one and 30 minutes per inch. A bed shall not be built where the soil evaluation indicates silty loam, clay loam, or clay.

(ii) Slope of the site shall not exceed eight percent.

(iii) Bed systems are more practical on sites that are long and narrow with a minimal slope.

(iv) All vertical and horizontal separation distance requirements shall be met.

(3) Design Criteria for absorption bed septic systems

(i) Pressure distribution is required for the installation of an absorption bed system. The local health department having jurisdiction may allow the use of siphon dosing on specific sites.

(ii) The maximum width of the absorption bed shall be 20 feet. The maximum length of each lateral from a pressure manifold shall be 100 feet. Utilizing a center manifold system, a bed may then have a maximum length of 200 feet. Laterals for siphon dosing systems in beds are limited to 75 feet.

(iii) The depth of the leachfield bed shall be between 18 and 30 inches below original ground level.

(iv) Laterals for the drainfield shall be spaced five (5) feet apart. Two and one-half feet (2 1/2') must be provided between the laterals and the sidewalls. In the maximum width of 20 feet, only four laterals may be installed.

(v) Using pressure distribution with a center manifold, a drainfield bed system shall have maximum dimensions of 205 feet by 20 feet.

(vi) The required bed bottom area shall be calculated from the application rates shown in Table 5.

TABLE 5  ABSORPTION BED SEPTIC SYSTEMS -- REQUIRED BOTTOM AREA

PERCOLATION RATE      APPLICATION RATE
MINUTES/INCH          GALLONS/DAY/SQ. FT.
------------------    ------------------

1 - 5                      0.95
6 - 7                      0.80
8 - 10                     0.70
11 - 15                    0.60
16 - 20                    0.55
21 - 30                    0.45
  30+                  Not Acceptable

(4) Construction of absorption bed septic systems

(i) Heavy construction equipment shall be kept outside the proposed bottom area of the bed.

(ii) The required drainfield or leach field bed bottom area is excavated as level as practical. The bottom and sides of the excavation are hand raked to reduce soil smearing.

(iii) After excavation, a six inch layer of aggregate is placed across the bottom of the drainfield bed.

(iv) The drainfield laterals are laid level on the aggregate and covered with aggregate to a level two inches above the top of the pipe.

(v) The entire leachfield bed area is covered with a permeable geotextile. Untreated building paper or a four inch layer of loose hay or straw may be substituted if a permeable geotextile is unavailable.

(h) Seepage Pits used for septic system effluent disposal

(1) General notes about seepage pit septic system components

A seepage pit, sometimes called a leaching pit, leaching pool, or incorrectly a cesspool, is a covered pit with an open-jointed or perforated lining through which septic tank effluent seeps into the surrounding soil.

[DF NOTE: the term drywell might be used for a seepage pit disposing of septic effluent in this case; by contrast, a cesspool holds both solid waste and septic effluent. I use the term "seepage pit" to refer to a pit used to dispose of septic effluent which originated as blackwater, the solids having been retained in the septic tank. I use the term "drywell" to refer to a pit used to dispose of graywater (greywater) which originated in sinks, laundry facilities, or showers. While their uses and implications of their presence at a property are quite different, the actual construction details of a seepage pit or a drywell are about the same.

See Cesspools for more in-depth information about those systems.

See DRYWELL DESIGN & USES for more in-depth information about those systems.]

(2) Site Requirements for septic seepage pits

(i) If soil and site conditions are adequate for absorption trenches, seepage pits shall not be used.

(ii) A minimum three foot vertical separation must exist between the bottom of any pit and the high groundwater level, bedrock, or other impervious layer.

(3) Design Criteria for seepage pits used to dispose of septic effluent

(i) The required "effective seepage pit area" is obtained from Tables 6 and 7 which are shown below.

(ii) No allowance for infiltration area is made for the bottom area of a seepage pit or the surface area of impervious soil layers (percolation rate slower than 60 minutes/inch).

(iii) The effective diameter of a seepage pit includes the diameter of the lining plus the added diameter provided by the annular ring of aggregate. Any area surrounding the liner with rock smaller than 2 1/2 inches in size shall not be included as part of the effective diameter.

(iv) Effective depth of a seepage pit is measured from the invert of the seepage pit inlet to the floor of the pit, with the thickness of impervious layers deducted.

TABLE 6 - SEEPAGE PITS - REQUIRED ABSORPTIVE AREA (IN SQUARE FEET) FOR HOUSEHOLD SYSTEMS

TABLE 7 - SEEPAGE PITS (CYLINDRICAL) - DIMENSIONS FOR REQUIRED ABSORPTIVE AREA (IN SQUARE FEET)

(v) Seepage pit linings may be pre cast concrete, cast-in-place concrete, or built in place with un mortared hollow cinder or concrete blocks. Concrete shall have a minimum compressive strength of 2,500 psi and 3,000 psi is recommended. Material with comparable structural strength, determined in accordance with commonly accepted sewage construction standards, principles or practices, may be allowed on an individual basis to prevent unreasonable hardship, provided public health is not prejudiced.

(vi) The separation between the outside edges of seepage pits shall be three times the effective diameter of the largest pit. This separation is measured as the undisturbed soil between pit excavations.

(vii) Seepage Pits shall be designed with sufficient structural stability to withstand lateral soil forces as well as vertical loads.

(4) Construction of seepage pits for septic effluent disposal

(i) Laterals leading to each seepage pit must be at least four inches in diameter with a minimum slope of 1/8 inch per foot.

(ii) Seepage pits shall not be connected in series. A distribution box shall be required where more than one seepage pit is installed.

(iii) The seepage pit excavation is to be raked to minimize sidewall smearing that may occur and reduce infiltration capacity. If groundwater is encountered, the pit shall be backfilled with the original soil to a level at least three feet higher than maximum groundwater and adjustments made in the pit dimensions.

(iv) The seepage linings are placed upon a concrete block, poured concrete, or pre cast footing and surrounded by a six inch minimum annular ring of large aggregate (2 1/12 - 4 inches in size).

(v) The rock [used to provide improved drainage around a seepage pit] is covered to prevent soil from filling the void spaces. Building paper, a four inch thick layer of hay or straw may be used.

(vi) The seepage pit cover shall be structurally sound and capable of supporting 300 pounds per square foot at the weakest point. Covers may be precast concrete or cast-in-place and shall be reinforced. A manhole with an opening of at least 20 inches in the shortest dimension shall be provided.

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SEPTIC AUTHORITIES
  75-A.0 New York State Regulation of Private Septic Systems
  75-A.1 Introduction to Septic Systems, Definitions of Septic System Terms
  75-A.2 Regulation of Sewage Treatment Systems by other agencies
  75-A.3 Sewage flows and design flow estimates
  75-A.4 Soil and site appraisal for Septic Systems
  75-A.5 House or building sewer line specifications
  75-A.6 Septic tank capacity requirements, installation, and placement
  75-A.7 Distribution lines, distribution boxes, gravity flow, pressure distribution, dosing, siphons
  75-A.8 Subsurface treatment of effluent, absorption field requirements, leach field design criteria
  75-A.9 Alternative Septic System Designs
  75-A.10 Other systems
  75-A.11 New product/system design interim approval

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

• Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
• Inspecting Septic Systems: Online Book, Inspection, Test, Diagnosis, Repair, & Maintenance: our Online Septic Book: Septic Testing, Loading & Dye Tests, Septic Tank Pumping, Clearances, details of onsite waste disposal system inspection, testing, repair procedures.


• Advanced Onsite Wastewater Systems Technologies, Anish R. Jantrania, Mark A. Gross. Anish Jantrania, Ph.D., P.E., M.B.A., is a Consulting Engineer, in Mechanicsville VA, 804-550-0389 (2006), Advanced Onsite Wastewater Systems Technologies. Outstanding technical reference especially on alternative septic system design alternatives. Written for designers and engineers, this book is not at all easy going for homeowners but is a text we recommend for professionals--DF.
• AEROBIC SEPTIC SYSTEMS
• Builder's Guide to Wells and Septic Systems, Woodson, R. Dodge: $ 24.95; MCGRAW HILL B; TP; Quoting from Amazon's description: For the homebuilder, one mistake in estimating or installing wells and septic systems can cost thousands of dollars. This comprehensive guide filled with case studies can prevent that. Master plumber R. Dodge Woodson packs this reader-friendly guide with guidance and information, including details on new techniques and materials that can economize and expedite jobs and advice on how to avoid mistakes in both estimating and construction. Chapters cover virtually every aspect of wells and septic systems, including on-site evaluations; site limitations; bidding; soil studies, septic designs, and code-related issues; drilled and dug wells, gravel and pipe, chamber-type, and gravity septic systems; pump stations; common problems with well installation; and remedies for poor septic situations. Woodson also discusses ways to increase profits by avoiding cost overruns.
• Country Plumbing: Living with a Septic System, Hartigan, Gerry: $ 9.95; ALAN C HOOD & TP; Quoting an Amazon reviewer's comment, with which we agree--DF:This book is informative as far as it goes and might be most useful for someone with an older system. But it was written in the early 1980s. A lot has changed since then. In particular, the book doesn't cover any of the newer systems that are used more and more nowadays in some parts of the country -- sand mounds, aeration systems, lagoons, etc.

Design Manuals for Septic Systems

• US EPA Onsite Wastewater Treatment Systems Manua [online copy, free] Top Reference: US EPA's Design Manual for Onsite Wastewater Treatment and Disposal, 1980, available from the US EPA, the US GPO Superintendent of Documents (Pueblo CO), and from the National Small Flows Clearinghouse. Original source http://www.epa.gov/ORD/NRMRL/Pubs/625R00008/625R00008.htm Onsite wastewater treatment and disposal systems, Richard J Otis, published by the US EPA. Although it's more than 20 years old, this book remains a useful reference for septic system designers. U.S. Environmental Protection Agency, Office of Water Program Operations; Office of Research and Development, Municipal Environmental Research Laboratory; (1980)
• Eco John® Innovative Toilet Solutions, Global Inventive Industries, Fountain Valley CA, PDF, product brochure
• "International Private Sewage Disposal Code," 1995, BOCA-708-799-2300, ICBO-310-699-0541, SBCCI 205-591-1853, available from those code associations.
• "Manual of Policy, Procedures, and Guidelines for Onsite Sewage Systems," Ontario Reg. 374/81, Part VII of the Environmental Protection Act (Canada), ISBN 0-7743-7303-2, Ministry of the Environment,135 St. Clair Ave. West, Toronto Ontario M4V 1P5 Canada $24. CDN.
• Manual of Septic Tank Practice, US Public Health Service's 1959.
  

Onsite Wastewater Disposal Books

• Onsite Wastewater Disposal, R. J. Perkins; Quoting from Amazon: This practical book, co-published with the National Environmental Health Association, describes the step-by-step procedures needed to avoid common pitfalls in septic system technology. Valuable in matching the septic system to the site-specific conditions, this useful book will help you install a reliable system in both suitable and difficult environments. Septic tank installers, planners, state and local regulators, civil and sanitary engineers, consulting engineers, architects, homeowners, academics, and land developers will find this publication valuable.
• Onsite Wastewater Treatment Systems, Bennette D. Burks, Mary Margaret Minnis, Hogarth House 1994 - one of the best septic system books around, suffering a bit from small fonts and a weak index. (DF volunteers to serve as indexer if Burks/Minnis re-publish this very useful volume.)
  While it contains some material more technical than needed by homeowners, Burks/Minnis book on onsite wastewater treatment systems a very useful reference for both property owners and septic system designers. We refer to it often. While Minnis says the best place to buy this book is at Amazon (our link at left), you can also see this book at Minnis' website at http://web page .pace.edu/MMinnisbook
  
• Septic Tank/Soil-Absorption Systems: How to Operate & Maintain [ copy on file as /septic/Septic_Operation_USDA.pdf ] - , Equipment Tips, U.S. Department of Agriculture, 8271 1302, 7100 Engineering, 2300 Recreation, September 1982, web search 08/28/2010, original source: http://www.fs.fed.us/t-d/pubs/pdfimage/82711302.pdf
• Soil Percolation Tests soil perc testing guide and instructions
• Percolation Testing Manual, CNMI Division of Environmental Quality, PO Box 501304, Saipan, MP 96950
• Planting Over Septic System Component", Daniel Friedman (author/editor, InspectAPedia.com), The Innovator, Winter/Spring 2008, BCOSSA, British Columbia OnSite Sewage Association, 201-3542 Blansard St., Victoria BC V8X 1W3 Canada
• Save the Septic System - Do Not Flush These Items Down the Toilet, Daniel Friedman, InspectAPedia.com - PDF document, printable
• SEPTIC STANDARDS
• SEPTIC MAGAZINES
  
• Septic System Owner's Manual, Lloyd Kahn, Blair Allen, Julie Jones, Shelter Publications, 2000 $14.95 U.S. - easy to understand, well illustrated, one of the best practical references around on septic design basics including some advanced systems; a little short on safety and maintenance. Both new and used (low priced copies are available, and we think the authors are working on an updated edition--DF. Quoting from one of several Amazon reviews: The basics of septic systems, from underground systems and failures to what the owner can do to promote and maintain a healthy system, is revealed in an excellent guide essential for any who reside on a septic system. Rural residents receive a primer on not only the basics; but how to conduct period inspections and what to do when things go wrong. History also figures into the fine coverage.
• Test Pit Preparation for Onsite Sewage Evaluations, State of Oregon Department of Environmental Quality, Portland OR, 800 452-4011. PDF document. We recommend this excellent document that offers detail about soil perc tests, deep hole tests, safety, and septic design. Readers should also see Soil Percolation Tests and for testing an existing septic system, also see Dye Tests
• Grass is Always Greener Over the Septic Tank, Bombeck, Erma: $ 5.99; FAWCETT; MM; This septic system classic whose title helps avoid intimidating readers new to septic systems, is available new or used at very low prices. It's more entertainment than a serious "how to" book on septic systems design, maintenance, or repair. Not recommended -- DF.
  
• US EPA Onsite Wastewater Treatment Systems Manual Top Reference: US EPA's Design Manual for Onsite Wastewater Treatment and Disposal, 1980, available from the US EPA, the US GPO Superintendent of Documents (Pueblo CO), and from the National Small Flows Clearinghouse. Original source http://www.epa.gov/ORD/NRMRL/Pubs/625R00008/625R00008.htm
• Water Wells and Septic Systems Handbook, R. Dodge Woodson. This book is in the upper price range, but is worth the cost for serious septic installers and designers. Quoting Amazon: Each year, thousands upon thousands of Americans install water wells and septic systems on their properties. But with a maze of codes governing their use along with a host of design requirements that ensure their functionality where can someone turn for comprehensive, one-stop guidance? Enter the Water Wells and Septic Systems Handbook from McGraw-Hill.
  Written in language any property owner can understand yet detailed enough for professionals and technical students this easy-to-use volume delivers the latest techniques and code requirements for designing, building, rehabilitating, and maintaining private water wells and septic systems. Bolstered by a wealth of informative charts, tables, and illustrations, this book delivers:
  * Current construction, maintenance, and repair methods
  * New International Private Sewage Disposal Code
  * Up-to-date standards from the American Water Works Association
  
• Wells and Septic Systems, Alth, Max and Charlet, Rev. by S. Blackwell Duncan, $ 18.95; Tab Books 1992. We have found this text very useful for conventional well and septic systems design and maintenance --DF. Quoting an Amazon description:Here's all the information you need to build a well or septic system yourself - and save a lot of time, money, and frustration. S. Blackwell Duncan has thoroughly revised and updated this second edition of Wells and Septic Systems to conform to current codes and requirements. He also has expanded this national bestseller to include new material on well and septic installation, water storage and distribution, water treatment, ecological considerations, and septic systems for problem building sites.
  
• The NSFC Products List has an excellent list of design manuals/modules available from their website or by telephone 800-624-8301
• Submissions welcome. send us a suggested document link or request an exchange of website links
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