2019-08-29_PERMIT FILE - M2019028 ‎(3)‎

• Permit No: M2019028
• IBM Index Class Name: PERMIT FILE
• Doc Date: 8/29/2019
• Doc Name: Adequacy Review Response
• From: J&T Consulting
• To: DRMS
• Email Name: AME
• Media Type: D
• Archive: No

RE: J-2 Contracting Company-DPG Pit-Permit No. M-2019-028
112(c) Permit Application
Adequacy Review No. 1 Response 8126119
-10-
41) The operator provided water level monitoring data from two sampling events (April 19,
2019 and May 8, 2019) for nine existing monitoring wells installed within and adjacent to
the proposed affected land boundary. Please commit to providing water level data
collected from these wells during five successive calendar quarters prior to commencing
with dewatering operations and/or slurry wall installation at the site.
Response: The existing monitor wells will be measured once a month to establish a
baseline for the seasonal groundwater elevations underlying the property. The
measurements are typically submitted with the annual report and renewal to the DBMS.
The current plan for the operation is to obtain a Weld County Use by Special Review
permit by April/May of 2020 and begin the slurry wall installation around the perimeter of
Phase 1. J-2 Contracting Company commits to providing data from the monitor wells for
one year prior to the slurry wall construction starting at Phase 1. The slurry wall
construction will take approximately 4 months to complete. Readings/measurements of
the monitor wells will continue on a monthly basis for the duration of the mining
operation.
42) The operator states the maximum exposed groundwater at the site during mining is
estimated at 0.38 acres. However, elsewhere in this exhibit, the operator describes a
dewatering ditch with a maximum surface area of 0.26 acres and a series of settling ponds
totaling 8.5 acres, which would give a total surface area of 8.76 acres. Please specify the
maximum amount of exposed groundwater to occur on site at any time.
Response: The maximum amount of groundwater that will be exposed based on the area
of the dewatering ditches (0.26 acres), fresh water pond (0.42 acres),process water ditch
(0.34 acres), settling ponds (1.24 acres) and recharge pond(6.51 acres) is 8.77 acres.
Exhibit H -Wildlife Information (Rule 6.4.8):
43) The Screening Report for Federal and State Listed Threatened and Endangered Species
prepared by Ecological Resource Consultants, Inc. includes the following
recommendations regarding migratory birds and raptor nest sites in the survey area:
a. Any future land use changes that occur in the survey area that remove
vegetation during the active nesting season for most migratory birds in this region
of Colorado (April 1 - August 31) should first ensure that active nests are not
disturbed.
b. In accordance with CPW guidelines, no new disturbance should occur within 1/3
mile of the active red-tailed hawk nest between February 15 and June 15, or until
the young have fledged. Once the nest becomes inactive, surface occupancy
may resume within the 1/3-mile buffer and vegetation occupied by the inactive
nest may be removed.
c. According to the USFWS Region 6 Migratory Bird Conservation Actions for
Projects to Reduce the Risk of Take during the Nesting Season, an active nest
survey should be performed "no more than 7-10 days prior to when work actually
begins on the project site" to determine the presence and activity status of nests
protected by the MBTA. If work for the project must begin prior to the nest
becoming inactive within the 1/3-mile buffer, further agency coordination would
be required.
V 305 Denver Avenue-Suite D•Fort Lupton CO 80621 •Ph: 303-857-6222•Fax:[phone]