The Hague Chronicle
In the February issue, I wrote about the inner workings of a typical septic tank. Not much to talk about since, in its simplest form, it?s merely an empty, watertight tank. Watertight is the key thing to remember. Many tanks that are installed around the lake are more than 30 years old and, more than likely, suffer from typical issues such as rust in metal tanks or pitting/cracking in concrete tanks, both of which cause leaks. Some estimates are that 60-75 percent of the septic systems in the Lake George basin would not pass inspection. Many would also not pass current building codes, which have setback requirements for distances between the tank system and the lake, tributaries, and drinking water wells.
This is where advanced treatment technology is a perfect fit. One unit that is being used extensively worldwide (over 10 million installed) and in the Lake George basin (about 40 installed) is the Clarus “Fusion” system. As shown in the diagram, the system combines the normal sedimentation and flotation of solid waste found in a typical septic tank, with removal of dissolved pollutants through anaerobic and aerobic treatment chambers. Biochemical oxygen demand (an overall measure of pollution) can be reduced from a 200-mg/l level in the effluent of a standard septic tank, down to 10-20-mg/l, a level typically found in a well-operated municipal secondary treatment plant. It basically eliminates the need for an extensive drain field. The effluent, after UV sterilization, can be discharged into a dry well. This works well for lakeside properties where ledge and poor soil create challenging situations.
Such is the case in Dunham's Bay, where many of these systems have been installed. Studies by The FUND for Lake George have shown improvement in near-shore waters where these units are being used. If you think this is new technology that is not tried and proven, think again.
First developed over 50 years ago, the design and operating simplicity have been tweaked through continuous improvements since then. It will fit into the space of your current septic tank. If you are thinking of upgrading your current system or are building a new home in a tight situation, you might want to consider this or similar technology for your application. Keep in mind that these units require an annual service contract to ensure efficient operation.
Eric Murdock, P.E., has been involved with installations in our area and has also taught the procedures for septic tank inspections in the Town of Lake George and in Queensbury.
Further information can be obtained from Eric at eric [at] onsite-engineering.us or by visiting his company website at onsite-engineering.com. Information on the Clarus Fusion system can be found at clarusenvironmental.com.
Visit the Hague Water Quality Awareness Committee on Facebook or contact one of our Steering Committee members: Al Rider (Chairman), Jim Beaty, Lance Clark, Ginger Kuenzel, Josh Patchett, Steve Ramant or me.