Orange County NC Website
Browse       Search
- • : <br /> 33. <br /> AGRICULTURAL <br /> EXTENSION <br /> SERVICE . <br /> North Carolina State University <br /> College of Agriculture and Life Sciences <br /> `1E)g,661'. - 6''8 <br /> Department of Biological and 6' 1 3 <br /> Agricultural Engineering <br /> Box 7625, Raleigh, NC 27695-7625 <br /> Telephone (919) 737-2675 <br /> Mr. Mike Adair <br /> Adair Realty <br /> Chapel Hill, NC <br /> Dear Mr. Adair: <br /> Reference: Community or Cluster Wastewater Treatment Facilities. <br /> Community onsite wastewater treatment facilities have been utilized <br /> extensively for many years. Extensive research and development activities <br /> have been ongoing, both in North Carolina and at research centers in the U.S. <br /> and Canada. There are many differences in the way systems perform. These <br /> differences are related to system design and conditions encountered on the <br /> site. <br /> There are concerns regarding the ability of wastewater receiver sites to <br /> adsorb nutrients and to treat water. These concerns are evaluated in the <br /> early phases of the design process. <br /> The ability of a site to absorb liquid is based upon both the textural <br /> classification of a soil and the mineralogy of the clay materials in the soil <br /> on a site. Clayey soils are typically slowly to very slowly permeable but <br /> they have a tremendous ability to fix or adsorb nutrients - especially <br /> phosphorus. Generally the clayey soils encountered in North Carolina can hold <br /> or adsorb up to several thousand pounds of phosphorus per acre. Agricultural <br /> lands typically require addition of up to 80 lb-P/ac/yr to facilitate crop <br /> production. Phosphorus recommendations are always based on soil testing! <br /> The phosphorus loadings from the six 4-bedroom homes proposed for the <br /> Orange County Project should be based on a phosphorus content in the waste- <br /> water of between 5 and 10 mg/1 and a flow of 480 gal/D/home. Phosphorus <br /> input is calculated simply as: <br /> 365 D/yr X 480 gal/D X 6 Homes X 10 mg/1-P*8.34 — 87.67 lb-P/yr <br /> Phosphorus is present in wastewater because of household cleaning products and <br /> from plant and animal tissue which incorporates phosphorus into bio-mass. <br /> Generally phosphorus is assimilated either as plant tissue on waste receiver <br /> sites or is stored in the soil. Assume allowable phosphorus loadings of <br /> 80 lb/a/yr. The land area required to assimilate the phosphorus is: <br /> 87.67 lb/Yr .. 1.09 AC <br /> 80 lb/ac/yr . <br /> • <br /> Cooperative Extension Work in Agriculture and Home Economics A&T and N.C.State Universities,100 Counties and U.S.Department of Agriculture <br />