This feature in Pumper reports noteworthy conversations that take place at the Pumper Discussion Forum, an online forum for industry professionals found at www.pumper.com. Pumper Discussion enables exchange of information and ideas on septic and drainfield installation and maintenance, trucks and equipment, portable sanitation, chemical and additives and much more. Information and advice in “Overheard Online” is offered in good faith by industry professionals. However, readers should consult in depth with appropriate industry sources before applying such advice to a specific business situation.
QUESTION:
Has anyone dug into older drainfield lines to repair or add new lines only to find chambers filled halfway with silt or sand? Is this a problem only in sandy soils? How does it get there? Will fabric cover help?
ANSWERS:
Are you sure it’s sand and not carryover/sludge from the tank that has dried out? If it is sand, I would assume that not enough hay or no fabric was used over the trenches. How old is the system? What state is it installed in? Just wondering if freeze/thaw is causing a problem.
◆ ◆ ◆
I’ve run into several systems that have filled with sand. I’m in Florida where the soil is very sandy. When the chambers are installed without cloth, the sand flows through the louvers on the sides.
◆ ◆ ◆
We are in northeast Kansas. We sell a lot of chambers to our installers. We also offer filter fabric, which is required in some of the counties around us. I am also seeing washed river rock used on top of chambers and I have also seen straw used. In sandy soils, you definitely need something to block off the fine silt or sand.
◆ ◆ ◆
Central Virginia has a lot of residual soils with high clay content, and we have witnessed not only mounds of fine sediments in the trenches but have often seen the louvers sealed up by fine clay sediments from backfill.
As far as I’ve seen, the companies have not altered their installation guidance to address leaching fines in anything but sandy soils. I’m dealing with two failures with reduced footprint systems. Both are about 10 years old.
