Question:

I read Pumper, and I could use a half dozen scholarly book titles on proper septic system construction, or good Internet sources. Could you please recommend them?

Answer:

I do not know of any current books that, in my opinion, properly explain to an onsite sewage system professional the necessary steps for “proper septic system construction.”

I have a copy of the so-called design manual titled Onsite Wastewater Treatment and Disposal Systems (dated 1980) from the U.S. Environmental Protection Agency. Unfortunately this manual was written by personnel from the agency who did not seem to have a good understanding of onsite sewage treatment systems and the information needed by an onsite professional in the field. In my opinion, this publication was mostly obsolete when it was printed.

I have some other books about onsite sewage treatment systems that have a lot of volume, but not much quality. The books also do not contain information on operation and maintenance, which are so necessary to the successful and long-term operation of an onsite sewage treatment system.

I suspect the authors have never designed an onsite sewage treatment system nor have been out in the field where the action is. They do not write the information that an onsite professional needs or wants to know. My evaluation is the authors do not adequately understand onsite sewage treatment systems.

IS THERE A BOOK?

I am answering your question about books on the subject of onsite sewage treatment in the hope that if such books are now available, information might be sent to me through Pumper at editor@pumper.com. If so, I will try to obtain a copy of those books and discuss them in future Answer Man columns.

You indicated you were a reader of Pumper, but did not indicate how long you had been doing so. I have written columns for many years about the basics of onsite sewage treatment, as well as described the design and construction of the individual parts of an onsite sewage system, such as the septic tank, design and installation of drainfield trenches, sewage treatment mound design and installation, effluent distribution by gravity in a series of trenches, cautions about the use of extra-wide seepage beds, monitoring the performance of an onsite system by using a water meter and inspection pipes in the trenches, determining the size of the onsite sewage treatment system, using and maintaining the onsite sewage treatment system, and many other related topics.

Pumper has an online service where back issues to March 2007 can be viewed from this Web page: www.pumper.com/editorial/archive. My suggestion is for you to decide on the subject you want to learn more about and check to see if you can find information from Answer Man columns in these back issues.

An example might be the sewage treatment mound. There are specific procedures for selecting the location of the mound, evaluating the natural soil, sizing the mound, and installing the mound. All of these details have been described in one or more of my Answer Man columns.

You can follow the same procedure for other parts of the onsite sewage treatment system. Good luck in your search for information and feel free to send me any other questions you have about the parts of an onsite system.

Question:

We have had massive amounts of small flies in the septic tanks in this area and they have made their way back into the homes. I have tried to get information on them but no one seems to know anything about them. How about you?

Answer:

An insect I have observed in septic tank inspection pipes, and that I had identified by an entomologist at the University of Minnesota is the dung fly. These are about the size of a large gnat, brown, and do appear in some septic tanks. According to the septic tank professional I was with when collecting the specimens, dung flies are an indication that the tank is working properly.

The dung flies were collected from a gravity system with trenches. Apparently the dung flies had no adverse effect on the system operation. I have no information on why the dung flies are in some septic tanks and not others.

I do not understand why the flies should be able to get into the home since the onsite sewage systems should be vented only through the roof vent of the house.

It may be possible that some of the P-traps in the homes are not full of water. A P-trap that often goes dry is located under the laundry tubs. Unless water is used to wash the floor, this trap receives no liquid. I suggest you advise your customers about this and have them check all their P-traps to be sure they are filled and remain filled.

If there is a County Extension Office near you, collect a sample of the flies and ask an entomologist to identify them for you. I suspect they are dung flies, which may be pesky, but I understand they do not bite.