NC0001422_Table 6-2 GW Remedial Alternative Effectiveness_20160201

TABLE 6-2
GROUNDWATER REMEDIAL ALTERNATIVE SCREENING - EFFECTIVENESS
L.V. SUTTON ENERGY COMPLEX
DUKE ENERGY PROGRESS, LLC, WILMINGTON, NC
Alternative 3
Alternative 1
Alternative 2
Hydraulic Containment &
Effectiveness
Monitored Natural Attenuation
Hydraulic Containment
Source Extraction
(MNA)
Wells/MNA
Wells/MNA
Eastern
North/
Eastern
North/
Eastern
North/
Site Area
FADA
Down-
FADA
Down-
FADA
Down -
gradient
West
gradient
West
gradient
West
Will remedial alternative be protective of human
TBD
Least
TBD
TBD
Moderate
TBD
TBD
Most
TBD
health?
When will remedial alternative be protective of human
Current
health?
TBD
Conditions
TBD
TBD
0-5 Years
TBD
TBD
0-5 Years
TBD
When will remedial alternative be protective of the
Current
Current
Current
environment?
TBD
Conditions
TBD
TBD
Conditions
TBD
TBD
Conditions
TBD
Has the potential remedial alternative been
demonstrated effective at any similar sites?
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Will remedial alternative permanently remove
contaminant from site?
TBD
Yes
TBD
TBD
Yes
TBD
TBD
Yes
TBD
Will remedial alternative reduce the toxicity of
contaminants?
TBD
No
TBD
TBD
Yes
TBD
TBD
Yes
TBD
Will remedial alternative reduce the mobility of
contaminants?
TBD
Yes
TBD
TBD
Yes
TBD
TBD
Yes
TBD
Can the effectiveness of a potential remedial
alternative be monitored, measured, and validated?
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Prepared By: PBW Checked By: KW
All options assume source removal and onsite landfill
TBD — To be determined by modeling with source removal. Risk assessment indicates unacceptable risk in fish tissue for arsenic, thallium, vanadium and
selenium in Lake Sutton. Additional data needed to determine if ash basins are contributors or will continue to be contributors following source removal.
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