We're definitely optimistic' 



(Continued from page 3) 



— The recirculating sand filter has gotten 

 considerable attention in Illinois. This system 

 uses a conventional setup plus an extra tank 

 with a sand filter. The effluent moves from the 

 first tank to the second tank, going through the 

 sand filter and is circulated over and over, with 

 fresh effluent being mixed with the semi-treated 

 material. The final discharged material is sup- 

 posed to be fully treated. 



The sand filter system is an estimated two to 

 three times more costly than a conventional sys- 

 tem. There have also been problems with polluted 

 discharges. 



— Aerobic systems are like small sewage treat- 

 ment plants. Treatment takes place in the air 

 instead of underground in a tank. But the effluent 

 must still be discharged underground. This sys- 

 tem can be two to three times as expensive as a 

 conventional system and requires more mainte- 

 nance. It may have applications for systems that 

 have occasional failures, according to Carlile. 



— Composting toilets are already manu- 

 factured and sold. They separate commode "black 

 water" from the "grey water" of sinks, dish- 

 washers, showers, washing machines and other 

 water-using appliances. The composting toilet 

 reduces the amount of water going into a septic 

 system by an estimated 45 per cent, reducing the 

 problem. Toilet wastes are treated separately in 

 a self-contained unit. 



— Evapotransporation beds are another al- 

 ternative — one best suited for dry climates. A 

 very large sand bed is built, covered with topsoil 

 and vegetated. Sewage is then introduced and, 

 according to the theory, dissipated by evapotrans- 

 poration. A test bed is now operating in Wake 



County, North Carolina, but it's experiencing 

 problems, according to Carlile. 



"We're not really enthused with this system 

 for this area (North Carolina)," Carlile adds. 

 "It's got some tremendous problems where rain- 

 fall exceeds the amount of evapotransporation." 



— The case system which uses a cinder block 

 distribution system is being tested at Plymouth 

 but doesn't look good for areas with a high water 

 table, Carlile says. 



"I don't think we're ready to take the alterna- 

 tive systems and start putting them in every- 

 where there's a failing system," Carlile concluded. 

 "But we feel confident enough to put them in 

 with control conditions. And we can go to any 

 site and make recommendations on modifications 

 that can be made to improve the site. 



"We're a long way from an optimum system, 

 but I think we're definitely optimistic," Carlile 

 continued, adding that North Carolina is the only 

 place he knows where people are actively working 

 toward solutions to the coast's unique septic 

 tank problems. "We've made improvements. We 

 know our alternatives will work better than con- 

 ventional systems. Now it's just a matter of 

 making more improvements." 



Want to know more about your present 

 septic system? Sea Grant has produced a 

 booklet "Your Home Septic System, Suc- 

 cess or Failure?" that tells how to recog- 

 nize and avoid problems. For your copy, 

 write: UNC Sea Grant College, Box 5001, 

 Raleigh, North Carolina 27607. 



University of North Carolina 

 Sea Grant College Program 

 1235 Burlington Laboratories 

 North Carolina State University 

 Raleigh, N.C. 27607 



