1 - paducah environmental information center

Paducah Site
MW93 ---MW95
MW94
MW90
MW91
MW9
o
from compliance (quarterly) monitoring
back to detection (semiannual)
monitoring. At this time, permit
requirements for the sampling and
analysis of 99'fc and Uranium were
inadvertently omitted from the Paducah
Site sampling program. The omission
was discovered in 2000 and the
analytes have been added back to the
program. An NOV was issued to DOE
by the state of Kentucky in 2000 for the
omission.
State Solid Waste Disposal
Regulations
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I I'
I.
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.,/C-404
PGDP
---...
- - MW226
MW227
\
Post-closure groundwater
monitoring continues for the C-746-S
Residential Landfill. The landfill
50 0 50100 Feet stopped receiving solid waste before
I""""Wii I July I, 1995, and was certified closed
o
MN- Monitoring Well Location
on October 31, 1995, by an independent
engineering firm. The groundwater
monitoring system for the C-746-S
Residential Landfill also encompasses
Figure 9.8 C-404 Landfill Monitoring wells.
C-404 Landfill includes immediate reporting to
KDWM of results in RGA wells exceeding
Kentucky maximum contaminant levels (401
KAR 47:030 Section 6) and statistical analysis of
the RGA monitoring results .. During 1999, TeE
exceeded maximum contaminant levels in four
upgradient RGAwells arid one downgradient
RGA well. Chromium also exceeded contaminant
levels in one upgradient RGA well. KDWM was
notified of the exceedences, as required by the
permit. Results were reported to KDWM on a
semi-annual basis, A summary of the maximum
resl;llts for each of the wells is provided in Table
9.1,
In accordance with permit· condition
llJ.7.3.i, the Director of KDWM was notified
May 10, 1996, in writing of a statistically
significant increase of 99Tc in MW 84. In 1998,
statistical analyses of downgradient test well
results compared with upgradient well results
showed no significant increases for any
analytes; therefore, KDWM removed the landfill
. • . . . !
the C-746-T Inert Landfill which was certified
closed in November 1992. The C-746-T Inert
Landfill has fulfilled its two yefITs of post-closure
environmental monitoring and maintenance
requirements and is awaiting final closure
approval from KDWM.
The groundwater monitoring system for C-
746-S and C-746-T consists of three upgradient
and nine downgradient wells (Figure 9.9). The
monitoring system is designed to monitor both
the upper portions of the RGA (URGA) and
lower portions of the RGA (LRGA). Upgradient
wells are recognized as MW 181, MW 220, and
MW 267 while downgradient wells are
recognized as MW 179, MW 221 thrU MW 225,
and MW 263 thru MW 266. An additional well,
MW 225, is monitored for static water level only.
During 1999, MW 353 was installed as a new
upgradient well because the proximity of MW
181, MW 220, and MW 267 to the landfill and
apparent groundwater mounding within the
aquifer created question of the true upgradient
nature of the wells. MW 353 will be added to the
9-10
Groundwater