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Difficult site septic systems design, inspection, repair: this document describes how to look for visual evidence of septic failure without or before testing a septic system and also
difficult site conditions that may require special measures to install a working septic system.
How to Inspect DIFFICULT SEPTIC SITES - Indicators of Difficult Septic Installation Sites
Our page top photo shows a fresh pile of rock and soil pushed over the edge of a steep rocky embankment near where we understood a septic tank to be located. Even before beginning our inspection we were concerned about what we might find since this was a difficult septic site.
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Looking for these conditions can give key information about the condition of the septic system before (and perhaps without) performing a septic loading and dye test
and also before (and perhaps without) invasive septic system inspection measures such as excavation.
Septic System Near a Stream exposed to flooding: at homes along Wappingers Creek in Dutchess County, NY, many septic tanks and drainfields are close to the waterway. Seasonal flooding such as shown in this photo make drainfield floods likely.
Even when flood conditions are not present, some drainfields may be too close to the creek to comply with state building and health codes, and worse, the high water table near the creek may prevent such systems from adequately treating septic effluent before it is discharged into the environment. Up-slope drainfields with effluent pumps or other special measures may be needed.
Septic Loading & Dye Tests for Properties Close to Rivers, Lakes, Streams, Ponds & Drainage Ditches
Dye tests of septic systems close to a lake or stream like this will sometimes discover that a property owner having a failing septic system succumbed to the temptation to simply run an effluent discharge line right from the end of a bad drainfield into the stream. Remember to look both above and below the water line for unexplained pipes in the area.
Steep Slope or Steep Site Septic Systems: If the building site is steep then special measures may have been needed to provide a working drainfield, or septic tank and field components may not be located near the building they serve and a pumping system may have been needed. Be on special alert for evidence of septic effluent breakout down-slope and at the bottom of steep slopes if septic components are nearby.
See STEEP SLOPE SEPTIC DESIGNS for details of how septic system need to be installed on steep or sloping sites in order to provide a working and durable drainfield.
Rocky Site Septic Systems: if there is insufficient depth of soil, proper treatment of septic effluent may be impossible using a conventional septic tank and drainfield. At some sites including the one shown in our page top photo, there may be so little topsoil over bedrock that there is not depth for a conventional septic tank to be buried. At such sites an installer may provide a "low boy" septic tank - one that obtains its volume by spreading over a larger footprint but with a shallow septic tank.
Shallow septic tanks may need special or more frequent pumping, and should be taken as an alert to inspect the D-box and drainfield carefully. A drainfield or soil absorption system needs (typically) about 2 ft. of soil below the bottom of the drainfield and the top of any nearby rock or high ground water.
So a drainfield installed in just a couple of feet of soil over bedrock is not going to perform well and may not be approved by local health officials.
Flat septic site near a lake: The land shown in this photo was a new home site which not only had standing water, but had only a few feet
of elevation between the yard top grade and the top of the nearby lake also shown in the photo.
The pipe shown was a footing drain emptying at the edge of a nearby lake. The septic tank and drainfield were buried in this area. I couldn't imagine how a conventional
septic tank and drain field would work in this location.
Here is a photo of the septic tank being installed at this property. That downspout
you see spilling by the foundation needs to be extended away from the home, but not where the roof drainage will simply enter the septic tank
and flood the leach field.
Here is a photo of the contractor's "repair" of the exposed footing drain and minimal soil depth at the property.
I can't inform readers of what the building department ultimately had to say about this installation.
Septic Site slope and runoff: Is surface runoff, sump pump drainage, storm drainage, or building roof runoff directed onto the septic tank or drain field area? (Risks flooding
Vehicle areas near Septic Tanks or Fields: Is there evidence of driving or parking on the leachfield or over a tank? (Risks damaging the system or dangerous collapse.)
At the property shown in this photo, the truck is parked over a "low boy" septic tank which was installed over bedrock.
The rock pile shown at the top of this page was behind this truck and pushed over the embankment to cover a failed seepage pit - there was no working drainfield at this site.
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Soil conditions before septic test start: What are soil and site conditions before start of the test: are there wet areas, evidence of surface
discharge of effluent or sewage, green grassy or soft, suspect areas?
Odors? It is important to be able to record
these conditions and their extent before and after testing.
Mound systems vs. original site: Has the mound system been constructed over a natural surface drainage path or stream? Are trees and stumps sticking
out of the mound (meaning it was used to bury site debris not to make a proper absorption field)?
These pages are part of our SEPTIC DYE TEST PROCEDURE for testing septic system function.
Technical review by industry experts has been performed and is ongoing - reviewers are listed at REFERENCES. Comments and suggestions for content are welcome.
Continue reading at RECENT SEPTIC WORK or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.
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Questions & answers or comments about septic systems installed on difficult, rocky, or steep sites
Use the "Click to Show or Hide FAQs" link just above to see recently-posted questions, comments, replies, try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.
Percolation Testing Manual, CNMI Division of Environmental Quality, Gualo Rai, Saipan provides an excellent English Language manual guide for soil percolation testing. Original source: www.deq.gov.mp/artdoc/Sec6art108ID255.pdf
Soil Test Pit Preparation, fact sheet, Oregon DEQ Department of Environmental Quality, original source www.deq.state.or.us/wq/pubs/factsheets/onsite/testpitprep.pdf The Oregon DEQ onsite water quality program can be contacted at 811 South Ave, Portland OR 97204, 800-452-4011 or see http://www.oregon.gov/DEQ/
Thanks to reader Michael Roth
for technical link editing 6/29/09.
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.
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. 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.
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
Mark Cramer Inspection Services Mark Cramer, Tampa Florida, Mr. Cramer is a past president of ASHI, the American Society of Home Inspectors and is a Florida home inspector and home inspection educator. Mr. Cramer serves on the ASHI Home Inspection Standards. Contact Mark Cramer at: 727-595-4211 mark@BestTampaInspector.com
John Cranor is an ASHI member and a home inspector (The House Whisperer) is located in Glen Allen, VA 23060. He is also a contributor to InspectApedia.com in several technical areas such as plumbing and appliances (dryer vents). Contact Mr. Cranor at 804-747-7747 or by Email: email@example.com
US EPA Onsite Wastewater Treatment Systems Manual [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)
"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
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.
Pennsylvania State Fact Sheets relating to domestic wastewater treatment systems include
Pennsylvania State Wastewater Treatment Fact Sheet SW-161, Septic System Failure: Diagnosis and Treatment
Pennsylvania State Wastewater Treatment Fact Sheet SW-162, The Soil Media and the Percolation Test
Pennsylvania State Wastewater Treatment Fact Sheet SW-l64, Mound Systems for Wastewater Treatment
Pennsylvania State Wastewater Treatment Fact Sheet SW-165, Septic Tank-Soil Absorption Systems
Document Sources used for this web page include but are not limited to: Agricultural Fact Sheet #SW-161 "Septic Tank Pumping," by Paul D. Robillard and
Kelli S. Martin. Penn State College of Agriculture - Cooperative Extension, edited and annotated by
Dan Friedman (Thanks: to Bob Mackey for proofreading the original source material.)
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. Tel: (416) 964-9415 1-800-268-7070 Email: firstname.lastname@example.org. The firm provides professional home inspection services & home inspection education & publications. Alan Carson is a past president of ASHI, the American Society of Home Inspectors. Thanks to Alan Carson and Bob Dunlop, for permission for InspectAPedia to use text excerpts from The Home Reference Book & illustrations from The Illustrated Home. Carson Dunlop Associates' provides extensive home inspection education and report writing material.
The Illustrated Home illustrates construction details and building components, a reference for owners & inspectors. Special Offer: For a 5% discount on any number of copies of the Illustrated Home purchased as a single order Enter INSPECTAILL in the order payment page "Promo/Redemption" space.
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The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume.
Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
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