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Septic System Leak?

PostPosted: Feb 14, 2009 1:24 pm
by Grandpa Caver
We recently discovered what appears to be leakage from someones septic system entering a well know cave. One of four possible sources is the landowners daughters home. When discussing the problem with the owner she asked if we could do a dye trace from the home to determine if it was indeed the source.

Our collective knowledge of dye tracing is very limited at best. We have the dye but do not have timely access to a proper trap or experience in using one. Would it be possible to use an activated charcol filter cartridge made for aquariums and if so, how do we "read" it?

We, including the landowner are anxious to see this resolved asap but the owner would prefer to know if her daughters home is the source before we turn it over to the proper authorities. Any help or advise would be greatly appreciated.

Brian Leavell

Re: Septic System Leak?

PostPosted: Feb 14, 2009 3:24 pm
by ArCaver
Is it close enough to the possible source to flush a highly concentrated scent such as peppermint through the system then wait to see if the odor comes into the cave?

Re: Septic System Leak?

PostPosted: Feb 14, 2009 3:28 pm
by boogercaver71
I believe you can use any activated charcoal. If the traps are placed in a moving stream, you must weight them down. It is also a good idea to run a trap before you add dye to get a base reading. You might contact the good people at the Karst Program at Western Kentucky University (Bowling Green). They might have the equipment to "read" any dye in the traps)

Re: Septic System Leak?

PostPosted: Feb 15, 2009 3:45 pm
by wyandottecaver

Gary Roberson and John bassett (a caver who does dye traces for a professional living) are doing a lot of work in the Binklys area. The Nature Conservancy Blue River Office also has experiance doing them. Both of these groups are well within easy access of the cave I think your speaking of and both would probably be glad to lend assistance technical or otherwise.

My experiance is that it really really pays to have someone who knows what they are doing help. Many times there are background contaminants (many detergents) that give false positives and sometimes the "catch" is so faint as to require lab work. Not like the good ole' days when you just dumped in a 55 gal drum of Florecin and looked for the green river :big grin:

Re: Septic System Leak?

PostPosted: Feb 15, 2009 10:21 pm
by reeffish1073
dye traceing works well, have seen it done for the same problem that you have encountered before. take the advice posted above and search out someone who has done the dye traceing before, they will be your best source of help. however if they are state employed, they are usually required to report isues like this, if it has a potential to get into a city water supply. but if this is so, it also helps get the problem fixed and the cave cleaned up!


Re: Septic System Leak?

PostPosted: Feb 16, 2009 7:01 pm
by Grandpa Caver
Thanks all for the advise. We are persuing the matter and will let ya'll know as soon as I have something to report.


Re: Septic System Leak? How To Run A Dye Trace

PostPosted: Feb 17, 2009 10:49 am
by Larry E. Matthews
Here in Tennessee, when we conduct dye traces for septic tank systems, we use the overkill method.

If the water entering the cave looks like sewage and smells like sewage, then it must be very concentrated and a straight line shot from the septic tank system.

Us about 1/4 pound of Fluorescein powder, or a liter (or more) of the pre-mixed solution and flush it down the toilet.

Then, go into the cave within a few hours and see if it is coming out. If not, go in every day for a week. If it hasn't shown up in a week, you probably have the wrong septic tank system.

Why do we use the overkill method? Simple. When the property owner sees the green dye coming out, he KNOWS it is his problem and he has to fix it. It stops a lot of arguments. Also, good evidence, if you take a photo, if you have to go to court.

NOTE: Here in Tennessee you must report all dye traces to a central clearing house in the Department of Environment and Conservation, to prevent erroneous testing results. See if your state has such a requirement.

If you don't have access to dye, you can do a Google search and find suppliers.

Larry E. Matthews
NSS #6792-F

Re: Septic System Leak?

PostPosted: Feb 17, 2009 6:42 pm
by wyandottecaver

the downside of the overkill method is that when folks drive by and see a bright green creek they get excited and generally create more interest than is desirable. If you are on a well downstream and your faucet water suddenly turns green without notice you also tend to get a bit upset....

Now, if it can be done in a discreet location far from prying eyes then the overkill method means you don't have to wait for the lab to start blasting..err exploring :big grin:

Re: Septic System Leak?

PostPosted: Feb 17, 2009 7:37 pm
by Larry E. Matthews
You seem to forget that this dye (I recommended 1/4 pound) is going into a septic tank system. So, you first have to color about 4,000 gallons, or more, or sewage before it even goes out the other end. That's 1,000 gallons of sewage in the septic tank and 3,000 gallons, or maybe more, in the disposal field.

I've done this for over 30 years and have never had a problem turning a creek green or coloring a nearby well.

How many years did you say you had done this for a living? How many septic tanks have you dye traced? Just curious.

By the way, if I did turn somebody's well green by flushing dye down a toilet and into somebody's septic tank system, I have done them a HUGE favor, don't you think?

Larry E. Matthews
NSS #6792-F

Re: Septic System Leak?

PostPosted: Feb 17, 2009 7:48 pm
by wyandottecaver
My experiance with dye is limited, and limited to lab-based charcoal/cotton traps using low doses. I use professionals like yourself :big grin:. You obviously have more experiance with the over-kill method.

I am confused however. If your going into the cave to "see if it comes out" I assume you mean you are coloring the water to an extent that it can be seen? In a slackwater/still pools situation or one where the exact ingress point is known I can maybe see a visual cue that would not be obvious downstream. But In the case of a cave carrying good volumes of flowing water (this one does) how do you get a visual cue without coloring a LOT of water?

Casteret colored an entire stretch of river green with Florecin :yikes:

Re: Septic System Leak?

PostPosted: Feb 17, 2009 8:06 pm
by Spike
A little bit of my background as it pertains to dye tracing.

I currently work for Missouri's Department of Natural Resources in the Geological Survey Program and have been involved with several hydrologic investigations that involved dye tracing and waste water. Last year I was the lead geologist in an investigation looking at groundwater contamination from a dairy operation. The Geologic Survey has done about 100 or so investigations of these types and there is a lot of institutional knowledge here.

That being said. A bit of advice.

Not all activated charcoal works. 10,000's of dollars have been wasted after it was learned that the charcoal used in a project was no effective. Work with a dye tracing lab that can supply you with charcoal that is known to work.

Collect background samples for at least 2 weeks. Domestic waste water contains some amount of just about every fluorescent dyes used, and is guaranteed to contain our favorite and most effective dyes. The trick is knowing how much is already moving through the system and then detecting at 3 to 10 times that amount to be fairly confident it is your dye.

Don't be afraid of having a visual detect. Turning stuff green. You are dealing with septic tank effluent. If green water shows up in someones drinking water they may stop drinking it. This is a good thing. If you have a visual detect in a surface stream your effluent is not staying in the subsurface long enough to have achieved proper treatment. This is pretty much true if you have any detection in any reasonable time period. In the case of recharge delineation we try to stay below visual to keep from alarming folks. But with potentially harmful inadequately treated waste water, alarm may be appropriate.

Dye reacts with waste water and degrades pretty quickly. You will need to use plenty of dye to make it though the treatment system and be detectable. Use charcoal packets even if you think you will have a visual detect. You may not.

Distance from source to detection matters. If the cave is 20 feet from the septic tank use less dye if 1000 feet use more.

Have a good lab analyze your packets. The folks at Bowling Green may be able to help, as may Ozark Underground Lab. Labs cost money to operate and use materials, there may be a fee.


Re: Septic System Leak?

PostPosted: Feb 17, 2009 8:41 pm
by Larry E. Matthews
Thank you Spike !!! Lots of good advice.

Yes, I remember the first time I flushed fluorescein dye down a toilet and the man's tap water turned bright green before I made it back to my office !!!

I didn't have to tell him some lab, some where, said his water had bacteria in it and that he needed to spend hundreds of dollars to treat it.

No, he could see the results for himself and he was very, very grateful to find out he had been drinking sewage. He never drank another glass from that well. The good news was that his well had "gone bad" just a few days before, so some crack or crevice had just opened up. We caught it just in time, before his whole family got sick.

Fortunately, city water ran down his street and he hooked on the next day.

Larry E. Matthews
NSS #6792-F
Professional Geologist

Re: Septic System Leak?

PostPosted: Feb 17, 2009 8:47 pm
by Larry E. Matthews
To Wyandotte Cave:

I was assuming from the original question, that the water entering the cave was so concentrated that it looked like and smelled like sewage. The point was not to color an entire cave stream, just the point where the suspect water was entering the cave. Probably from a roof drip or a small infeeder.

If it was not concentrated enough to look bad and/or small bad, then my method clearly would not work.

I have faith in activted charcoal in relatively clean water, but I do not trust it to work in sewage.

I have done dye tracing in ground water, and that is another whole ball game. Dealing with sewage requires different techniques.


Re: Septic System Leak?

PostPosted: Feb 18, 2009 7:22 am
by Grandpa Caver
Here is a bit more detail regarding this situation. When first witnessed three weeks ago the waste was indeed obvious as bits of what appeared to be toilet paper were clinging to rocks where it entered the cave. The smell was horrific! We've since had a good bit of rain and the leak is not visibly apparent but the smell, allthough lessened is still very noticeable.

The nearest possible source(s) is about 400 to 500 feet from where the leak is noted in the cave and I'm guessing maybe 60+ feet higher in elevation. Egress of the cave stream is at on old mill that has received a lot of attention as the mill was recently restored as an historic site. I'm guessing if we turned the stream and the creek it flows into green it would certainly alarm the locals!

PS: The mill, allthough renovated, is not fuctioning.


Re: Septic System Leak?

PostPosted: Feb 18, 2009 8:59 am
by Larry E. Matthews
Gee, you see bits of toilet paper? And you wonder if it "might" be sewage?

Get the dye and PROVE which septic tank is causing the problem.

Worried about alarming the locals? Are you serious?

Shouldn't they KNOW there is sewage in the stream? Don't their children play in it? Don't their pets drink from it? Maybe they fish in it and eat the fish.

This sounds like a very serious, potentially life-threatening problem that should be corrected immediately. Call your local Health Department, or whoever in your State is repsonsible for stream pollution and septic tanks and report this problem. That is what they are there for. Why run the dye test yourself? They is what they are paid to do.

Somebody could catch hepatitis or some other serious disease.

Larry E. Matthews
NSS #6792-F