PERMFILE139661

• Permit No: M2005080
• IBM Index Class Name: Permit File
• Doc Date: 6/19/2006
• Doc Name: Motions for Conditions
• From: Harvey W. Cutris and Assoc
• To: DMG
• Media Type: D
• Archive: No

EXHIBIT C
MEMORANDUM
To: Harvey W. Curtis
FROM: Jon R. Ford, P.E.
FILE: 1237BWH01
DATE: June 14, 2006
RE~ Allen Pit, File No. M-2005-080
As you requested, we have reviewed the above-referenced application and other publicly
available data as discussed below. Based upon this review, we conclude the following:
1) The average annual depth to ground water will likely be approximately 10 to 14 feet
at the north end of the site, and approximately 8 to 9 feet at the south end and average
about 9 feet. Limited evidence suggests that the seasonal fluctuation on the depth to
water is on the order of 4 feet. Therefore, the average depth to ground water on the
site could be less than 7 to 9 feet during the spring and summer.
2) The depths to ground water reported by the Applicant (16-21 feet) for three
monitoring wells (located approximately as shown on Objectors' Exhibit 10) are
probably in error.
3) The single depth to ground water measurement made in the three monitoring wells on
the site by the Applicant do not assess the seasonal fluctuations in the water table that
occur at the site. A series of monthly measurements over at least two high ground
water seasons would be necessary to determine the magnitude of the seasonal
variation.
4) The depths to ground water from the off-site water wells and as reported by the
Applicant, as shown on Objectors' Exhibit 9, are not relevant because these wells are
completed in bedrock aquifers, not the outwash alluvium that the Applicant proposes
to mine.
CONCERN ABOUT APPLICANT'S REPORTED DEPTH TO GROUND WATER
The Applicant drilled three monitoring wells, located as shown on Objectors' Exhibit 10.
However, the Applicant did not report how and when the single measurement was made of depth
to ground water in each well, nor did he report how the monitoring wells were cleaned up prior
to making the measurements. Without this information, we cannot conclude that the
measurements are valid. Typically, monitoring wells are bailed until the water pulled from the
well is clear to remove the low permeability layer that develops on the borehole face as a
consequence of the drilling process. If this is not done properly, it may take many days before a
monitoring well fills to the true water level below the ground. There is no evidence that the
wells were cleared prior to making the water level measurement.
If the Applicant measured the depth to water immediately after the monitoring wells were
drilled, the depth to water level would be incorrect because the water level inside the well did not
have time to rise to the true depth to water. This problem is avoided by making a series of
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