The proposed E.coli and enterococci standards of 126 CFU/10oml and 35 CFU/100ml represent a significant change to the disinfection standard.  Where is the evidence to suggest that discharge water quality requires significantly higher levels of disinfection?

I note that the rationale for this proposed change is consistency with state water quality standards pursuant to 9VAC25-260-170.  However, a review of that standard indicates that the "bacteria criteria shall apply to protect primary contact recreational uses in surface waters...". 

In my experience, most receiving waters for these discharges are NOT primary contact recreational surface waters - many tend to be ephemeral streams and low-flow unnamed tributaries.  If a significant increase in disinfection is warranted, perhaps a distinction between recreational and nonrecreational receiving waters is a more appropriate solution.