1 - paducah environmental information center

Annual Site Environmental Report for 1999
groundwater contamination from the site. These
residents' out-of-service wells are being utilized
by DOE for sampling as a result of written
agreements. Residential wells that are no longer
sampled have been capped and locked.
Groundwater Monitoring
Program
The primary objectives of groundwater
monitoring at the PaducBh Site are to detect as
early as possible . any contamination resulting
from past and present land disposal of wastes
and to provide the basis for developing
groundwater quality assessments if contamination
is detected. Additional objectives outlined in
DOE Order 5400.1, General Environmental
Protection Program, require that groundwater
monitoring at all DOE facilities "". determine
and document the effects of operations on
groundwater quality and quantity." The Order
specifically requires groundwater monitoring to
be conducted on-site and in the vicinity of DOE
facilities to accomplish the following:
• obtain data to determine baseline
conditions of groundwater quality and
quantity;
• demonstrate compliance with, and
implementation of, all applicable
regulations and DOE orders;
• provide dati to permit early detection
of groundwater pollution or
contamination;
..
provide· a .. reporting. mechanism for
detected groundwater pollution or
contamInation;
• ". . identify ... existing and potential
'. groundwater contamination sources and
" maintain' surveillance of these sources;
and
• provide data for making decisions
about land disposal practices and the
management and protection of
groundwater resources.
These objectives are outlined in three
documents relating to groundwater monitoring:
Paducah Gaseous Diffusion Plant Groundwater
Protection Program Management Plan (Miller
1997), Groundwater Protection Plan (Miller
1998), and the Paducah Site Environmental
Monitoring Plan (BJC 1998). Scheduled
sampling continues for more than 150
monitoring wells and residentiru wells in
accordance with DOE orders and federal, state,
and local requirements. Well sampling is
included in several different monitoring
programs, which are described below.,",
RCRA Permit Monitoring Programs
At present, the only hazardous waste
facility at the Paducah Site that requires
groundwater monitoring is the C-404 Landfill
(Figure 9.8). The C-404 Low-Level Radioactive
Waste Burial Ground was used until 1986 for the
disposal of uranium~contaminate4 solid wastes
when it was determined that of. the wastes
disposed there, gqld dissolver precipitate was
considered a hazardous waste under RCRA. The
landfill was covered· with a RCRA-compliant
clay. cap and was certified closed as a hazardous
waste landfill in 1987. The landfill is now
monitored under post-closure monitoring
requirements~ According to EPA Hazardous
Waste . Permit· KY8-890~008-982, .
14 wells
(MWs 84-95, 226, and 227) monitor groundwater
qUaIity -of.the VCRS (four wells) and the
underlying RGA (ten: wells) during.the required
posi-closurecare on a semiannual basis.
During 1999, MWs at the. C-404Landfill
were sampled and analyzed for total and
dissolved arsenic, cadmium, chromium, lead,
mercury, and selenium and TCE. Evaluation of
the groundwater monitoring data collected at the
Groundwater
9-9