NC0063096_201 Facilities Plan_20060502

State of North Carolina
Department of Environment
and Natural Resources
Division of Water Quality
Michael F. Easley, Governor
William G. Ross, Jr., Secretary
Alan W. Klimek, Director
To:
From:
Date:
Subject:
Hannah Stallings
Teresa Rodriguez
EAST NPDES Program
May 2, 2006
NCDENR
MEMORANDUM
EIS - Western Wake Regional Wastewater Management Facilities
The NPDES Program has reviewed the April 2006 Draft EIS for the Western Wake Wastewater
Management Facility and offers the following comments:
• The 80 gpcpd used for the Holly Springs for flow projections has not been justified by Holly
Springs and is an outstanding comment in the Holly Spring's Engineering Report which was
revised on March 15, 2006.
• The Division acknowledges that the evaluation of the final discharge configuration will take
place upon the final design phase and will be reviewed at a latter time. Although a dye study
was suggested for a bank discharge, mixing characteristics for a bank discharge can also be
predicted and evaluated using modeling. The document predicts that a diffuser may be exposed
above the water level under low flow conditions. Under such conditions a diffuser will not
provide any more dilution than a single pipe discharge and it may be perceived as an obstruction
in the river and disturb recreational activities and fish passage.