2017-06-26_HYDROLOGY - M1999120

• Permit No: M1999120
• IBM Index Class Name: HYDROLOGY
• Doc Date: 6/26/2017
• Doc Name: Water Monitoring - Groundwater
• From: L. G. Everist, Inc.
• To: DRMS
• Email Name: ECS
• Media Type: D
• Archive: No

DRMS ANNUAL REPORT - GROUNDWATER MONITORING REPORT
SITE: L.G. Everist, Inc. - Fort Lupton Sand and Gravel, M-1999-120
DATE: June-2017 Page 1 of 2
Fort Lupton monitoring well data from January-2016 through March-2017 is attached. Prior data
has been submitted in prior reports and permit amendments. A map of the monitoring well
locations is also attached. (MW= monitoring well)
All wells that are listed in the data file are also shown on the map. Some of the wells have been
abandoned for various reasons (usually they have been mined through). The abandoned wells
are shown in the data file and map for consistency.
The majority of the monitoring wells have maintained groundwater levels within the baseline
ranges established in L.G. Everist's (LGE) final adequacy response for the DRMS permit
amendment in October-2012. This includes wells in areas where we are not yet mining, and
also wells along the perimeters of slurry walls - showing that the water is still flowing around the
slurry walls in natural patterns.
Some monitoring wells at Fort Lupton have hit groundwater level trigger points (as per the
groundwater monitoring program agreed on in the Oct-2012 DRMS amendment), and then the
groundwater has balanced out and the levels have come back to be within baseline ranges. No
outside parties were affected, so no mitigation for outside parties has been required.
Following is a listing of wells which have exceeded baseline ranges at some point within the last
year and a half, or have had other notable changes. There is an explanation of the raw data
and any contributing external (or internal) factors. Any investigation and mitigation are also
noted. There have been no adverse effects on neighbors with any of these wells.
MW6 -This well is considered internal to LGE operations. It is located within the permitted
area, to the west side of the Swingle-South slurry wall. The entire Sandstead cell is located to
the west. MW6 has fluctuated with the dewatering the south end of the Sandstead cell, and is
outside baseline ranges, but because the well is internal to LGE and fluctuating water levels
would only affect the operator, no mitigation is necessary. Note that the nearest external well,
MW20 (located on the west side of Sandstead) has stayed within baseline ranges.
MW8 -This well is located on the south side of CR18, outside of the Swingle-North slurry wall,
and directly across from a neighboring mining operation, which is unlined. The neighboring
mine's dewatering efforts are having an effect on the nearby groundwater levels, because MW8
was within baseline ranges for the first few years. The well has generally been below the low
threshold number since January 2007 - soon after mining and dewatering began in the
neighboring mine. There are no residential neighbors nearby to be affected.
MW9 -This well is quite far north of any LGE operations, but is located directly across CR25
from the adjoining mine's (see MW8) main entrance. Again, their dewatering efforts are causing
the local groundwater to decrease. There are no residential neighbors nearby to be affected.
The same conditions exist as noted under MW 8.
MW10 -This well is even farther away from LGE operations - it is north of MW9, and adjacent to
an irrigation ditch. This well is so far from LGE operations, it really makes no sense to be on
LGE's well list. It is closer to another mine (see MW8 and MW9), than to any LGE permitted
areas. There are no residential neighbors nearby to be affected. The levels in this well just
recently dipped below baseline data -within the last 3 months. We will continue to monitor.
FL-DRMS-AnnRpt&GrWtrMon-2017.docx