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9. The Division believes the proposed location for MW-006 is appropriate because it is located downgradient of the second mine panel (Years 6-15) and is within close proximity of the fault which bisects the second panel. However, MW-006 is likely not appropriately located for the first panel (Years 1-5). Located within this first panel is an un-lined sedimentation basin excavated into the Codell Sandstone. The Division is concerned this in-pit sedimentation basin could act as a groundwater infiltration gallery and therefore the installation of an additional monitoring well appears warranted. The location of this additional well would be most appropriate downgradient of the in-pit sedimentation basin (near Arroyo B). Please demonstrate how the location of MW-006 is sufficient to demonstrate compliance with the requirements of Rules 3.1.5(5), (10) and (11), 3.1.6, and 3.1.7 for activities occurring in the first two mine panels(Years 1-15)or commit to installing an additional well. GCC agrees that the proposed MW-006 is likely not well suited for the first panel (Years 1-5). The sedimentation basin was excavated at the very beginning of the life of the Quarry, before the Plant was erected, and subsequently expanded in 2010. Pursuant to condition 1 of Operations mining Permit No. M-2002-004, GCC installed six (06) groundwater monitoring wells at the facility: MW- 001, MW-001A, MW-002, MW-003, MW-004 and MW-005. Monitoring well MW-001 was installed inside the first panel (Years 1-5), specifically 1,440 feet west and 200 feet north of the southeast corner of Section 13 Township 22 South, Range 65 West. The purpose of this monitoring well was to screen across the Codell Sandstone. MW-001 was plugged in April 2008 as mining of panel years 1-5 progressed. Groundwater was never found. In order to provide a monitoring point downgradient of the mine limits and an eventual replacement for MW-001, monitoring well MW-001A was installed early 2003 north of MW-001; specifically 1,000 feet west and 1,550 feet north of the southeast corner of Section 13 Township 22 South, Range 65 West (downgradient of panel years 1-5) to further evaluate whether the limestone/sandstone or sandstone/shale contacts were water-bearing units. No water was noted during drilling MW-001A and from the time of installation in 2003 until 2013, MW-001A never produced enough water to sample. Also, no saturation in the Fort Hayes Limestone or the Codell Sandstone has been noted during mining. On March 12, 2013 GCC submitted a Technical Revision application to modify the Groundwater Monitoring Plan. The application elaborated on groundwater sampling events from all Monitoring Wells present at the time,including MW-001A. In accordance with the provisions of Rule 16.2 of the State Engineer's Water Well Construction Rules, GCC requested DRMS'approval to plug and abandon wells MW-001A, MW-002, MW-003 and MW-004. The Technical Revision application was approved by DRMS on March 20, 2013. The sedimentation pond is excavated into the upper portion of the Codell Sandstone. The pond is pumped down after a maximum of 3 days of stormwater accumulation. As noted in the CCG report (2016), "given the pump setting, the water level in the basin stays below the Fort Hayes/Codell contact. The limited water that accumulates in the basin primarily evaporates. Some limited amount of water may persist at times in the basin due the impracticability of pumping it completely