Environmental Impact Statement - radioactive monticello

Environmental Impacts of Operation
physical and chemical stresses and introduction of nonnative species. The physical and
chemical stresses include urban, industrial, and agricultural contaminants (e.g., nutrients, toxic
chemicals, sediments); stream modification; water diversions; land-use changes (e.g.,
residential, recreational, agricultural and industrial development); dredging; shoreline
modifications; wetland elimination and modification; dams and impoundments; impingement
and entrainment in water-intake structures; thermal loading from cooling water; and major
degradative incidents or catastrophes (Weitzell et al. 2003; Genet and Chirhart 2004). These in
turn can affect fish, benthic macroinvertebrates, and plankton populations; cause a loss of
habitat; cause deformities or tumors in fish and other biota; and contaminate fish, which leads
to restrictions on human consumption.
Industrial, municipal, agricultural, and power plant usage of the Mississippi River occurs
between St. Cloud and the Twin Cities (NMC 2005a). While pollution from domestic sewage
has been reduced since passage of the Federal Water Pollution Control Act of 1972 (CWA), the
Mississippi River still receives contaminants from agricultural, industrial, municipal, and
residential sources (Fremling and Drazkowski 2000). The Monticello intake area requires
dredging every six to eight years to prevent excess sand and silt from being drawn into the
plant circulating water system (Amish et al. 1978). This causes a temporary, localized stress to
aquatic biota within the immediate area near the Monticello plant.
The river water supply is adequate to meet the needs of the facility for cooling purposes under
* all conditions. The staff, while preparing this assessment, assumed that other industrial,
commercial, or public installations could be located in the general vicinity of the Monticello site
prior to the end of Monticello operations. Any discharge of water by such facilities into the
Mississippi River would be regulated by the MPCA. The discharge limits are set considering
the overall or cumulative impact of all of the other regulated activities in the area. Compliance
with the CWA and its NPDES permit minimizes Monticello's cumulative impacts on aquatic
resources. Continued operation of Monticello would require renewed discharge permits from
the MPCA, which would address changing requirements so that cumulative water quality
objectives would be served.
Future contributions to cumulative impacts to aquatic resources within the Mississippi River
would generally occur from those actions that currently cause impacts (e.g., human habitation,
urban and industrial development, agriculture, recreational fisheries, and spread of nonnative
species). The quality of the aquatic resources within the Upper Mississippi River will continue
to decline unless inputs of sediments, nutrients, and toxic substances are reduced or eliminated
(Fremling and Drazkowski 2000).
The potential exists for the expansion of nonnative species that have already begun to occur in
the Upper Mississippi River, and for additional nonnative species to become established within
the river. Four species of Asian carp are established within the Upper Mississippi River. As
mentioned, the common carp (Cyprinus carplo) is a prominent species within the Monticello
area, while the grass carp (Ctenopharyngodon idella), silver carp (Hypophthalmichthys
molotrix), and bighead carp (H. nobilis) have become established within the Upper Mississippi
.August 2006 4-45 NUREG-1 437, Supplement 26 1