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SEPTIC SYSTEM INSPECT DIAGNOSE REPAIR
SEPTIC CARE INSTRUCTIONS
SEPTIC D-BOX INSPECTION
SEPTIC DRAINFIELD FAILURE DIAGNOSIS
SEPTIC DYE TEST PROCEDURE
SEPTIC FAILURE SIGNS
SEPTIC INSPECTION & TEST GUIDE
SEPTIC LIFE EXPECTANCY
SEPTIC SUPPLIES & PARTS
SEPTIC SYSTEM DESIGN ALTERNATIVES
SEPTIC SYSTEM DESIGN BASICS
SEPTIC SYSTEMS, HOME BUYERS GUIDE to
SEPTIC SYSTEM SAFETY WARNINGS
SEPTIC TREATMENTS & CHEMICALS
SEWAGE BACKUP PREVENTION
SEWAGE EJECTOR / GRINDER PUMPS
SEWER GAS ODORS
SEWER LINE REPLACEMENT
SINKHOLES, WARNING SIGNS
SOAKAWAY BED FAILURE DIAGNOSIS
SULPHUR & SEWER GAS SMELL SOURCES
TOILETS, INSPECT, INSTALL, REPAIR
TRAPS on PLUMBING FIXTURES
TREATMENTS & CHEMICALS, SEPTIC
VIDEO GUIDES: Septic Videos
WASHING MACHINES & SEPTIC SYSTEMS
WATER SOFTENERS & CONDITIONERS
WATER SUPPLY & DRAIN PIPING
WASTEWATER TREATMENT BASICS
WATER, WELLS, WATER TANKS: TESTING GUIDE
WINTERIZE A BUILDING
How to abandon a septic tank, cesspool, drywell: this document outlines basic procedures for finding and safely abandoning unused septic systems and cesspools, and provides some safety suggestions for septic system inspectors, septic system inspections, septic pumping contractors, and home owners. When a septic tank, drywell, or cesspool is no longer to be used, either because a building is connected to a municipal sewer or because the old tank is being left in place and a new septic installed elsewhere, there are very important safety steps that should be taken.
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Safety Concerns in Abandoning Septic Systems, Seepage Pits, Cesspools, Drywells, even dug wells
Septic tanks, cesspools, and drywells present serious hazards including septic cave-in's or collapses, methane gas explosion hazards, and asphyxiation hazards. Simple precautions which we describe here can help avoid a dangerous septic, cesspool, or drywell hazard.
In addition to having been consulted in fatalities involving humans, we have learned that falling into septic tanks and cesspools is a risk for animals as well. Readers should also see specific warnings about cesspools at Cesspool Safety.
Watch out: for unsafe septic tanks and cesspools or drywells and for systems that were not properly abandoned. In 2008 Mark Cramer shared a report from an owner that that their horse fell into a septic tank and died tragically before it could be rescued. The collapsing septic tank was not in the location which the owners thought it would be found, and clearly it had an unsafe cover. We were consulted in a Long Island death of an adult who fell into and was buried in a collapsing cesspool. And in 2012 we were contacted for comment involving the death of two boys who fell into and perished in an "abandoned" septic tank or cesspool that lacked a safe cover. See SEPTIC & CESSPOOL SAFETY.
It is important to properly abandon un-used septic tanks, cesspools, or drywells. If an old septic tank, cesspool, or drywell is simply "left alone" there may be very serious cave-in or fall-in safety hazards.
Septic tank, drywell, or cesspool abandonment or tank closure may involve complete tank removal, tank crushing (steel septic tanks), or most common with site-built tanks/cesspools/drywells, and with concrete tanks, the cover is opened and the tank is filled-in with rubble and soil. Details of septic tank, cesspool, drywell abandonment procedures are discussed in this article.
Septic Tank Abandonment Choices
When a septic tank is no longer going to be used, various factors determine what will happen to the old tank:
Example State Requirements for Septic Tank Abandonment
Frequently Asked Questions (FAQs)
Question: is it ok to fill a concrete septic tank with sand?
Can you fill a concrete septic tank in with sand? We are preparing to hook up to city sewer and need to know what the best cost-effective way to handle our septic tank will be. - 8/13/2012
Cassandra, the tank gets pumped, cleaned, and filled - sand should be acceptable to your local building department.
Question: can I convert an old septic tank into a pond?
I've got an old septic tank in the garden of the house I'm buying. Is it possible to turn it into a pond? I was wondering if I could line it with butyl liner on a cushion of sand (to be more hygienic) - Victoria 9/25/2012
Is it possible to turn an old septic tank into a pond? I was wondering whether I could line it with butyl liner on a cushion of sand. - Victoria
While the conversion you describe is technically feasible, it seems a bit deep, unsanitary, and cost-unbalanced an idea to me. To reduce the sanitation hazard you'd need to
Question: how do I abandon a septic tank that remains under the slab of an existing building addition
I have a client with a problem I can't fix YET ! She thinks that a remodel to her living room years ago was built on an abandoned septic. We have relocated all plumbing and waste lines in the area to start with . The air still feels bad , the close hanging the closet get mold on them in a short time and she is sick all the time. If there is a septic under the slab what is keeping it from just drying out and if I jack hammer the slab , how do i remove it all and fill in ? HELP - B.B. 11/15/2012
Your question is a reminder of the suggestion that it would have been best to properly abandon a septic tank before ever building over it. I had to deal with this problem at a building whose prior owner built a screened porch atop an old steel septic tank. Luckily the porch had just a wooden floor built on piers, so it was easy to cut an opening in the floor, find the septic tank opening(s), and inspect, pump, clean, and fill the tank. In my case the tank was a steel one that had a rusted-through bottom, had been out of service for decades, and was not particularly smelly. We filled in the tank with stone, rubble, and clean soil just to make sure that it did not collect water (and produce odors) in the future.
In your case, I'd proceed to locate, inspect, and abandon the under-slab septic tank as follows:
That should be sufficient to stop the odor problem and eliminate future hassles with an old septic tank that smells, collects groundwater, collapses, or is in general a possible hazard.
Questions & answers or comments about problems with the operation of aerobic septic systems
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Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.