still considered experimental, regula- 

 tions issued under the state's Ground 

 Absorption Act now recognize the right 

 of property owners and developers to 

 use these systems on problem sites as 

 long as they can be proved effective. 

 Similar regulations are in effect in 

 other states. 



State of the art 



For Carlile these rulings have been 

 an important boost to his work. Ac- 

 cording to Steve Steinbeck with the 

 North Carolina Department of Human 

 Resources' Division of Health Services, 

 they open the way for more and more 

 breakthroughs in the area of alter- 

 native on-site waste disposal. "Systems 

 such as low pressure distribution are 

 fast becoming the state of the art in- 

 stead of experimental," he says. 



Studies probe the basics of septic waste disposal 



Beyond the issue of disposal system 

 design and maintenance there are still 

 many questions that need to be 

 answered about on-site waste disposal 

 in general. In addition to the Sea Grant 

 project, several other studies are being 

 conducted in North Carolina. A special 

 state task force has been formed to ad- 

 dress the issue of alternative sewage 

 disposal. 



One important area of research con- 

 cerns the effectiveness of alternative 

 systems in filtering contaminants. As 

 part of the Sea Grant study, 

 microbiologist Mark Sobsey of the 

 University of North Carolina at 

 Chapel Hill is studying the effec- 

 tiveness of the low pressure and mound 

 systems in removing bacteria and 

 viruses in wastewater. Viruses are par- 

 ticularly difficult to filter out because 

 they are so small and can rapidly 

 migrate through pores in the soil. At 

 several study sites, Sobsey is assaying 

 waters from special observation wells 

 and surface waters adjacent to the 

 alternative systems. 



In addition, a network of 168 

 monitoring wells has been set up along 

 the coast in 11 counties to determine 

 the extent of water table fluctuations 

 both tidally and seasonally. This infor- 

 mation is important for designing the 

 disposal systems and in refining septic 

 tank regulations. 



One of the biggest concerns along the 

 coast has been the impact of pollution 

 from poorly treated wastewater on 

 shellfishing waters. Last year more 

 than 400,000 acres of clam and oyster 

 waters were closed to harvesting in 

 North Carolina. While Bob Benton of 

 the state's Shellfish Sanitation Divi- 

 sion believes that "septic tanks play a 

 significant role in the closure of these 

 areas," he is unable to quantify 

 "significant." 



Bridging the gap 



"There are so many other factors," 

 emphasizes Charlie Jackson with the 

 Shellfish Division, "that we can't make 

 a blanket statement." Runoff from in- 

 dustry, farming operations and even 

 the natural decay of plant and animal 

 material contribute to the closure of 

 shellfishing waters. 



According to Steve Steinbeck with 

 the Division of Health Services the 

 connection between septic tank pollu- 

 tion and shellfish contamination has 

 never been clearly demonstrated. 

 "There's been a lot of innuendo, but 

 the data is not conclusive. We'd like to 

 have some good hard evidence," he ex- 

 plains. 



In an effort to answer some of the 

 more basic questions about wastewater 

 contamination, the Coastal Plains Re- 

 gional Commission recently awarded 



an $80,000 research grant to the 

 North Carolina Department of Human 

 Resources' Division of Health Services. 

 According to Steinbeck, who is the pro- 

 ject director, the focus of the research 

 will be on determining the fate of con- 

 taminants and nutrients typically 

 found in wastewater as they move 

 through the soil. Both Carlile and Sob- 

 sey are participating in the study. 



The research project will involve 

 detailed monitoring of conventional 

 and modified septic systems in Hyde, 

 Craven and New Hanover counties. 

 These counties, Steinbeck explains, 

 were selected because they represent a 

 range of soil problems, "from very well 

 drained soils to muck soils, from 

 organic soils to hard pans." 



Steinbeck believes that the results of 

 the study will be important in shaping 

 future septic disposal regulations and 

 in providing researchers with an oppor- 

 tunity to quantify the role of soil and 

 ground water characteristics in 

 wastewater treatment. 



Beyond the coast 



The problem of on-site waste dis- 

 posal isn't limited to coastal North 

 Carolina. Problem soils and high water 

 tables extend across state borders and 

 beyond the coastal plain into Pied- 

 mont and mountain regions. 



