Alternative septic systems
I’m thinking of buying some land in Virginia; however, the property, which includes a large concrete-block industrial building, is in a 100-year flood plain. I’d like to convert the building into a residence, but getting a septic permit will be difficult due to proximity to the river and the absence of a local sewer system. I’d like to know what type of septic system offers the best shot at getting approval.
M.A. Wilcoxen, Redwood City, CA
Charles McIntyre, assistant director of Penn State University’s Housing Resource Center, replies: Sewage regulations vary within Virginia. You should contact the local health department in the county where you’re considering purchasing land and ask them about the following nontraditional septic systems to see which, if any, can be installed under local regulations.
Elevated sand mounds — This type of system consists of a regular septic tank and a drainage area that serves the same purpose as a drainage field, except that it’s constructed above ground. Usually the drainage area is a rectangular mound with perforated pipe and stone contained within the top of the mound and sand below. The effluent must be pumped from the septic tank to the elevated mound. Certain counties in Virginia discourage the use of elevated sand mounds.
Stream discharge — Because your site is located near a stream (river), it may be possible to obtain a stream discharge permit. A septic tank is needed and chlorination of the waste water is required. Chlorination involves installing a chlorination device and chlorine-contact tank. Chlorine removal, or de-chlorination, may also be required. This type of system is fairly common in Virginia when used for low-volume systems, under 1,000 gallons per day.
Small package treatment plants — Typically, this type of system is installed on site as a single unit and serves the same function as a full-size waste water treatment plant. Small package treatment plants come in a variety of sizes and are quite effective, but they’re expensive. It’s also somewhat difficult to secure an application and receive approval for this type of system in certain areas of Virginia.
Remote drain field — This system involves pumping the septic-tank effluent to an adjacent site. The maximum distance to the site is governed by local regulations as well as the topography and soil characteristics of the site. The purchase price of the adjacent site is usually the controlling factor.
On-site storage and removal — It is possible to store sewage effluent on site and have it pumped into a tank truck to be hauled away to the local treatment plant for treatment and disposal. However, it’s unlikely that you’ll be able to obtain approval for such a system. The homeowner pays the county for the service (pumping and treatment), but the county health department has the immediate responsibility of cleaning up if something goes wrong with the system. So the county is seldom willing to enter into such an agreement.