640.703.  Definitions. — For the purposes of sections 640.700 to 640.755, the following terms mean:

  (1)  "Animal units", shall be defined by rules of the department in effect as of January 30, 1996;

  (2)  "Animal waste wet handling facility", includes all gravity outfall lines, recycle pump stations, recycle force mains and appurtenances;

  (3)  "Class IA", any concentrated animal feeding operation with a capacity of seven thousand animal units or more;

  (4)  "Class IB", any concentrated animal feeding operation with a capacity between three thousand animal units and six thousand nine hundred and ninety-nine animal units inclusive;

  (5)  "Class IC", any concentrated animal feeding operation with a capacity between one thousand animal units and two thousand nine hundred and ninety-nine animal units inclusive;

  (6)  "Class II", any concentrated animal feeding operation with a capacity of at least three hundred animal units, but less than one thousand animal units;

  (7)  "Department", the department of natural resources;

  (8)  "Facility", any class IA concentrated animal feeding operation which uses a flush system;

  (9)  "Flush system", a system of moving or removing manure utilizing liquid as the primary agent as opposed to a primarily mechanical or automatic device;

  (10)  "Sensitive areas", areas in the watershed located within five miles upstream of any stream or river drinking water intake structure, other than those intake structures on the Missouri and Mississippi rivers.