South Carolina Code of Regulations
Chapter 61 - DEPARTMENT OF HEALTH AND ENVIRONMENTAL CONTROL
Subchapter 61-9 - Water Pollution Control Permits
Subchapter 61-9.503 - STANDARDS FOR THE USE OR DISPOSAL OF SEWAGE SLUDGE
Part D - PATHOGENS AND VECTOR ATTRACTION REDUCTION
Section 61-9.503.D.31 - Special definitions

(a) "Aerobic digestion" is the biochemical decomposition of organic matter in sewage sludge into carbon dioxide and water by microorganisms in the presence of air.

(b) "Anaerobic digestion" is the biochemical decomposition of organic matter in sewage sludge into methane gas and carbon dioxide by microorganisms in the absence of air.

(c) "Density of microorganisms" is the number of microorganisms per unit mass of total solids (dry weight) in the sewage sludge.

(d) "Land with a high potential for public exposure" is land that the public uses frequently. This includes, but is not limited to, a public contact site and a reclamation site located in a populated area (e.g., a construction site located in a city).

(e) "Land with a low potential for public exposure" is land that the public uses infrequently. This includes, but is not limited to, agricultural land, forest, and a reclamation site located in an unpopulated area (e.g., a strip mine located in a rural area).

(f) "Pathogenic organisms" are disease-causing organisms. These include, but are not limited to, certain bacteria, protozoa, viruses, and viable helminth ova.

(g) "pH" means the logarithm of the reciprocal of the hydrogen ion concentration measured at twenty-five degrees Centigrade or measured at another temperature and then converted to an equivalent value at twenty-five degrees Centigrade.

(h) "Specific oxygen uptake rate (SOUR)" is the mass of oxygen consumed per unit time per unit mass of total solids (dry weight basis) in the sewage sludge.

(i) "Total solids" are the materials in sewage sludge that remain as residue when the sewage sludge is dried at 103 to 105 degrees Celsius.

(j) "Unstabilized solids" are organic materials in sewage sludge that have not been treated in either an aerobic or anaerobic treatment process to include extended aeration, activated sludge or other treatment processes approved by the Department.

(k) "Vector attraction" is the characteristic of sewage sludge that attracts rodents, flies, mosquitos, or other organisms capable of transporting infectious agents.

(l) "Volatile solids" is the amount of the total solids in sewage sludge lost when the sewage sludge is combusted at 550 degrees Celsius in the presence of excess air.