chlorine for septic

[linda in se ny]

We just had our tank pumped (it was long overdue but we don't flush paper or use chlorine to speak of). Now the guy that pumped it says we should poor 5 gallons of chlorine directly into the tank before we close it to clean leach fields. This makes no sense to me but maybe theres something I'm missing?

[Cabin Fever]

A properly functioning leachfield will have a thin biological mat formed on the bottom and sides of the trench walls. This "biomat" is necessary for two reasons. One reason is that it slows the infiltration of wastewater into the soil thus causing the wastewater to flow down the trench and spread over a greater area in the trench (more area = better treatment). The other purpose of the biomat is to ensure that water infiltrates slowly into the soil so the soil below the trench does not become saturated and anaerobic.

The only reason why someone would recommend pouring bleach into the leachfield is that he may believe that the biomat is too thick and the bleach will oxidize and reduce the thickness of the biomat.

A thin biomat is good, a thick biomat is bad. It can lead to plugging of the leachfield and consequential surfacing of wastewater into the yard or backups of wasterwater into the home. A biomat can become too thick if:
[1] the septic tank is not pumped often enough (due to high wastewater strength or sludge entering the drainfield),
[2] the septic system recieves more wastewater than it was designed for, or
[3] the trenches were dug too deep (where there is less oxygen in the soil).

With all that said, I have never known of any example where chlorine or bleach did what it was suppose to do (ie, reducing the biomat thickness therby increasing wastewater infiltration). I have heard that the use of hydrogen peroxide has been effective....but it takes many, many gallons.

Question: Were you having backup or wastewater surfacing issues before you had your septic tank pumped?

[linda in se ny]

We have clay soil so sometimes the area is wet but we've never had a back up in 22 years since we put in the system. We were required to put in 500 ft of leachfields due to the poor perc. I think he felt we had let it go too long and sludge may have entered the leachfield but I'm not rushing to do it. Thanks for such a thorough explaination.

[SpaceCadet12364]

You could always use a couple of bottles of the stuff that is bacteria-related....think the company that puts out the one we have used is Roebic, we get it at Lowes. So, that way less risk of totally hosing up your septic system (which a bunch of bleach might do), but it should help break down some of the stuff that apparently the septic guy thinks you may have a problem with.

Easy stuff to use....usually is something to the effect of you pour it into the main line through the toilet, and flush once. We usually do this sort of treatment just before going to bed, so it has a chance to do its thing. They also make soap digesters and such too.

[tamsam]

It sounds to me like he wants to come pump it again real soon. Chlorine kills the bacteria in septic systems. When you shock a well with bleach you should run only enough water through the pluming in the house to get the smell at each facet then use and outside facet to pump the well out. Good luck with your septic. Sam

[countrysunshine]

Showing my ignorance here........when ya'all say leach field is that the same as a finger system? It sounds like it to me but all I know about finger systems is they never work around here and are required by law. So, most people have them installed but don't run through them.

I was just curious.

One reason we will never sell our house is because I don't want to mess with the problems I am sure would arise about our septic. We have a huge tank and put no gray water in it. It just drains where the gray water does.

[Wis Bang]

I used to send truckloads of Sulfuric Acid to a jobber on Eastern Long Island. He went thru 3 - 4 loads [@48,000 Lbs each or 3137 Gal each] every week, all year long.

He was located at the rear of a honeydippers yard and had two old tank trailers for storage along with a 6 wheel tanker for delivery.

He used to fill 30 gal carboys at jobsites where they were trying to open plugged laterals using undiluted sulfuric acid.

12,000 gal a week is almost a railroad tanker!

I imagine there are a lot of 50 yr old septic systems in Long Island but that is still a lot of acid! I used to joke w/ my wire's uncle in Northport that I was going to test his tap water w/ litmus paper b/4 I drank any...