limit standards fall into two categories, technology based (or
effluent discharge standards) and water quality based limits (or instream
standards) (Hammer and Hammer, 2001). A technology
based standard is a minimum level of technology and pollution
control performance that must be achieved by municipal wastewater
treatment (Freeman, 1980). Water quality based standards,
which are more stringent, are based on the water quality standards
applicable to the receiving water; these are employed to protect a
specific water body and they are based on the assimilative capacity
of the stream (Hammer and Hammer, 2001). These are a derivative
of the self-purification capacity of the stream