From The Ground Up
APPALACHIA/June 15, 1988*
* not full-text
Septic Systems
Our efforts to deal with septic systems have begun again with a national search for appropriate technologies. A volunteer and Old Hutman, engineer Hank Parker, has been the mainstay of an attempt to find usable remote-location systems that can be adapted to our facilities or purchased off the shelf. Few backcountry operations have the low ambient temperatures, moisture and volume of use that our facilities endure. So far, our research indicates that those operations that do have similar variables have similar problems.
In our own back yard, the state of New Hampshire is dealing with septic issues on the summit of Mount Washington, and the Forest Service struggles with the Tuckerman toilet operation. With flush systems, current operations require that leach beds be replaced every 7 to 10 years, and since our locations are perched high on ridgetops with little subsoil, all fill must be flown in, a yard at a time, by helicopter. This means a pile of sand purchased in the valley for $200 costs $8000 delivered.
Holding tanks that collect solids are prone to crack because of the freeze-thaw cycle, a cycle that sometimes keeps the solids in the bottom of the tank iced until mid-July. Every two years, each flush system requires pumping to remove solids that have collected. Last year we flew in 80 55-gallon drums and our "Mudsucker" pump to Lakes in early June, filled 'em up and removed them by helicopter two at a time. At $575 per hour for helicopter time, even a short run with these barrels to the homestretch of the Auto Road adds up to thousands of dollars. We still must pump these barrels out and run the contents through a treatment facility at additional cost. Finally, our water supplies in the flush huts have occasionally suffered from low-water periods, which (as many can attest last summer when drought forced us to ration water at four huts) can practically shut down the system.
Bruce Sloat, Huts Manager in the late '60s and early '70s, designed a haul-out toilet that is now in use at Zealand, Galehead and Greenleaf. A 55-gallon drum is placed beneath a USFS forest toilet seat, and the barrel collects solids and liquids. Once filled, the crew caps the barrel, and with ample elbow grease, they winch the barrel out of its vault, set it on casters and roll it out. Crews then use a "crapper snapper" to lift and carry the barrel to the helicopter pad. The problem with this system is that, in general, it's unpleasant. In hot weather and still winds, when ventilation fans stall, it can be odoriferous. By collecting solids and liquids, total weight increases tenfold, compared to a flush system that leaches off most liquids. Finally, each full barrel weighs nearly 500 pounds, a heavy load indeed. Still, as Bruce said at a meeting in January, no one has devised a better method.
What are the solutions? Ideally, any new system would handle a large volume of waste, separate solids from liquids, require a low level of maintenance with simple mechanics, reduce handling and helicopter time, lengthen the life of the leach beds, reduce the amount of waste pumped from tanks, and lower operating costs. Easier described than done.
So far, the best two alternatives, which still need study, are the Shasta system and the "strainer in a barrel." The Shasta system consists of a large box in which a large strainer is placed. Fecal matter is plumbed so that the strainer traps the solids while allowing the liquids to continue to the holding tank and leach bed. Solids are then removed--(after being given time to shed water weight)--into barrels or, if 100 percent pathogen kill is reached, the material could be distributed. We suspect that a properly working system would meet all requirements with the exception of the handling problem. Trapping and drying waste before it reaches the tank will reduce helicopter time,lengthen the life of the leach beds (it's the dissolved solids clogging the pores of a leach bed that hasten its death), reduce the pumping of tanks and lower operating costs.
The strainer in a barrel concept mirrors Shasta, on a smaller scale. We would fabricate barrels to fit existing vaults with a basket to collect solids and an outlet for liquids in the bottom of the barrel. This outlet would be plumbed into a leach bed (we already have them in place for grey water treatment). Once the basket is filled, crews will still have to remove it, only this time it should be a third the weight of the previous barrel. The solid can either be flown out or allowed to "cook" in the sun with hopes of distributing the material on site. Testing of both systems may begin soon.