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SEPTIC SYSTEM INSPECT DIAGNOSE REPAIR
SEPTIC CARE INSTRUCTIONS
SEPTIC D-BOX INSTALL REPAIR
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
WATER CONSERVATION MEASURES
WATER SOFTENERS & CONDITIONERS
WATER SUPPLY & DRAIN PIPING
WATER, WELLS, WATER TANKS: TESTING GUIDE
WASHING MACHINES & SEPTIC SYSTEMS
WASTEWATER TREATMENT BASICS
WINTERIZE A BUILDING
This document provides important safety warnings for septic systems and cesspools, and provides some safety suggestions for septic system inspectors, septic system inspections, septic pumping contractors, and home owners.
Green links show where you are. © Copyright 2014 InspectApedia.com, All Rights Reserved.
Providing inspection and diagnosis of on-site waste disposal systems is an extremely valuable public service which helps protect people from expensive unanticipated septic system repair costs and helps protect public health by assuring sanitary disposal of sewage and gray water waste from buildings.
More importantly though, septic system inspections may detect and warn about serious safety hazards at some properties.
The strong warnings issued below intend to reduce septic system safety hazards for inspectors and property owners/occupants, but it is not the author's intention to dissuade inspectors from providing this valuable service.
Watch out: 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 or expensive septic problem.
The septic hazard news video at right recounts a child falling into a septic tank and a separate septic fall-in fatality.
Citation of this article by reference to this website and brief quotation for the sole purpose of review are permitted. Use of this information at other websites, in books or pamphlets for sale is reserved to the author.
Examples & Case Reports of Fatal Hazards at Open or Insecure Septic Tank, Cesspool, Drywell Covers
Safety Warning: there is a very high risk of fatal falls into septic tanks, cesspools, or drywells: danger lurks at cesspools, open covers, tanks or tank covers in poor condition, and from high levels of methane gas CH4 or hydrogen sulfide H2S.
These septic system dangers include the risk of collapse, falling, asphyxiation, explosion, and other potentially fatal hazards as well as risks of unsanitary conditions such as bacterial or viral infections. This hazard is more than theoretical. We have personally assisted in investigation of several septic or cesspool fall-in fatalities and are aware of others.
Inspecting a mobile park housing migrant workers at a New York farm, Steven Vemilye and Daniel Friedman documented various immediate and serious safety hazards at two open or semi-open septic tanks and cesspools. Shown above is a home-made dry-laid concrete block well (unstable) surrounding an open septic tank.
The property manager left the concrete septic tank cover off and just tossed a light section of plywood over the system in order to make frequent septic tank pumping easier. This mobile home collection was occupied by many families including families with small children. An adult or child falling into an open septic tank is very likely to die quickly.
Above Mr. Vermilye, accompanied by the attorney who had asked us to perform a site inspection, was demonstrating the instability of the covers over septic facilities at this location. [As we document
Watch out: Readers trying to diagnose and deal with sudden soil subsidence or yard collapses should
also see SINKHOLES, WARNING SIGNS.
There can be other unexpected hazards when inspecting building sites and septic systems. In the photo series above, the author was inspecting the home shown from outside before looking in the crawl space to locate the main waste line exit point and thus before predicting the probable location of the septic tank.
Walking close to this house should have set off an alarm about possible unsafe conditions: poor maintenance, old home, of an age likely to have used a steel septic tank. In fact the author found the tank very quickly by stepping through its cover, avoiding serious injury or even possible fatality mostly by luck. It was throw myself sideways into the briars and garbage at the site or fall completely into the septic tank.
A Safety Guide for Septic System Inspection, Cleaning, Pumping, and Homeowner Care
Do not drive over the septic tank or septic piping
Unless special provisions have been made such as protection of sewer piping and septic tanks from damage, vehicle-rated septic tank covers, or similar steps, do not drive vehicles over the septic system.
Driving over septic tanks, septic piping, or drainfields risks costly damage to the septic system and may also be dangerous.
The bulldozer in our photo (left) was called to help remove a truck which drove over septic system components leading to a surprise collapse.
If a septic line must be run under a driveway, for example to pass from a building to the septic tank, the line must be protected by choice of materials (schedule 40), or placed in a covered and protected trench at adequate depth (such as with concrete covers over the trench) to avoid damage.
If a septic tank is to be located below a drive or parking area, it too must be properly designed and protected from collapse.
A septic drainfield cannot be located below a driveway or parking area. Doing so will prevent proper drainfield operation due to soil compaction and also due to loss of proper evaporation of moisture through the surface, as well as almost certainly leading to crushed broken piping.
Methane Gas Hazards around Septic Systems, Methane Gas Toxicity vs. Methane Explosion & Asphyxiation Risks, How to Measure Methane Gas Levels
Methane Gas Hazards are primarily of explosion or asphyxiation - see METHANE GAS HAZARDS for details.
We commented above at Septic System Safety that methane gas which maybe encountered in septic system is both explosive and an asphyxiant.
A thoughtful reader, George Fielder, previously a salesperson for GfG Instrumentation, pointed out that these are the hazards. (We had inaccurately stated that methane gas was "toxic".)
Readers who need more details about the safety concerns regarding methane gas in and around septic systems should be sure to review the septic system methane gas hazards and measurement and references cited at SEPTIC METHANE GAS (also see Septic Methane Gaslinks listed at the "More Reading" links at the bottom of this article in this article)
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.
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. 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.
Properly abandoning a septic tank, drywell, or cesspool which is no longer in use involves at least the following steps:
Continue reading at CESSPOOL SAFETY WARNINGS or select a topic from the More Reading links shown below.
Suggested citation for this web page
Green link shows where you are in this article series.
Frequently Asked Questions (FAQs)
Question: digging with backhoe broke the septic tank
i was digging in my back yard and hit the septic tank and broke it open, it spilled into a 8 foot by 12 hole prolly 6 feet deep. i buried it, is that gonna cause any problems? - Steve 9/19/2011
Of course. You destroyed the septic tank.
Watch out: when the septic tank has been damaged there is risk of a collapse or someone falling in - risking a highly likley fatality.
Question: why did my septic treatment plant cave in?
I have wlwyestion my treatment plant has cave in - Valeria 11/3/12
Watch out: for safety when there are signs of a cave-in you should rope off the area and keep people away until a professional has investigated and repaired the site as necessary.
Question: report of septic tank fatality on Fafa Island in Tonga
Watch out: My brother-in-law just died yesterday from jumping into a septic tank to clean at his workplace on Fafa Island in Tonga. He was obviously unaware of the present dangers and unfortunately OH&S laws dont exist in the country. He was only 27. Please be careful! - Lavinia 2/19/2013
Reply: List of Recent Septic Tank, Cesspool, or Drywell Fatalaties or Catastrophes
We are saddened and dismayed to read of your brother-in-law's death in a septic tank. Indeed these fatalities occur everywhere, even where there are safety regulations, though perhaps at a less frequent rate where the dangers are better known.
If you can send us added details that might help other readers and I'll add them at SEPTIC TANK ACCIDENT REPORTS in hope that we can make more people aware of the dangers involved in un-covered or inadequately-covered septic tanks, cesspools, and drywells and about the risk of fatality on entering such a tank.
Falling into a septic tank, drywell, or cesspool is quickly fatal, either from being buried by falling soils and debris, or by asphyxiation. Septic gases are highly toxic and can kill in just minutes of exposure. Even leaning over an empty (just pumped) tank has led to collapse and fatality of a septic pumper.
Septic tank, drywell, cesspool and related safety articles are listed at the top of this page.
Question: green cover marked Poison Gas
A relative is looking to buy a house that was built in 1935. On the property there is a green cover maybe 3 feet circumfrance and says on it Do Not Open--Poison Gas--Danger. What could that be? - Stephanie Kascack4/3/2013
Meanwhile, because the condition of the septic tank and components are unknown and because you don't even know what the green cover covers, much less its condition, it woudl be safe to mark off the area and keep people away until you know what's there and its condition.
Question: why is my septic tank not draining properly?
(Mar 13, 2014) Joe said:
I recently had my septic tank pumped, everything was fine for about a week or so and now I have sewage backing into my house every few days. I have snaked it and had a video inspection of the line from the house to the septic tank and everything looked fine. Is it possible that the company that pumped the tank may of ran over the distribution box or septic piping? Any other ideas on why it wouldn't be draining correctly?
Joe, with apologies that it sounds glib, sure, anything is possible - we don't know where the septic pumping company drove their truck.
Just inspecting the sewer line between house and tank, while useful to determine that that line itself is not blocked, doesn't diagnose the problem. If the septic tank outlet line or D-box were blocked, indeed that would explain constant backups into the house.
I suggest opening the septic tank access cover to inspect the sewage level. Watch what happens when you flush toilets and run water in the house. If the tank exit is blocked for any reason (including a failed drainfield or a blocked outlet) you'll see wastewater level rise over the baffles in the septic tank.
Let me know what you find
Question: how long can we live in a home with a malfunctioning septic system?
(3 days ago) sandie said:
For what period of time can you live in a home with septic system malfunctioning
For what period of time can you safely inhale septic sewer gases
Reply: making emergency use of a septic tank when the drainfield has failed
"Can" meaning physically able, and "should" are different data points.
Here's a "zero time" answer:
You should not allow methane (sewer gases) to accumulate in a building as (depending on the concentration of methane present) the building can be blown up by a spark or flame.
Details are at inspectapedia.com/septic/Methane_Gas_Hazards.htm
Human exposure limits for methane gas (figure sewer gas)
It is indeed possible to make emergency use of a septic tank when a drainfield is blocked, by pumping out the tank and severely constricting water use. However typically you gain just a week or two of use at most before the septic tank re-fills, and you may gain no time at all if groundwater is leaking back into the septic tank or if the drainfield is bakflowing into the septic tank.
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