2015-07-30_REPORT - M2008006

• Permit No: M2008006
• IBM Index Class Name: REPORT
• Doc Date: 7/30/2015
• Doc Name: Annual Fee, Report & Map
• From: Connell Resources
• To: DRMS
• Email Name: MAC
• Media Type: D
• Archive: No

Ms. Ioana Comanidu
RE: SerFer Pit Lining
May 20, 2015
Page 2 of 3
40.45°, Lon: W 104.96°, and Elevation: 4,975 ft. The Highpointe Estates weather station is
located at Lat: N 40.46°, Lon: W 104.95°, and Elevation: 4,955 ft. The source for this data is
http://www.wunderground.com/weatherstation/WXDailyHistory.asp?ID=KCOWINDS9 and
http: //www.wunderground. com/weatherstation/WXDailyHistory. asp?ID=KCOWINDS3,
respectively. The on-site rain gage data was used in calculating precipitation during this time; the
weather stations allowed verification of the rain gage data. During the 91 -day period a total of
4.64 -in of precipitation was measured onsite. Rain was measured directly in the rain gage. Snow
was melted with a known volume of hot water, which was subtracted from the total volume of
melted snow plus added water in the rain gage, and the water content of the snow was recorded
as precipitation in inches. A contributing area of 32.8 acres was used to calculate the volume of
runoff into the test area, assuming a runoff ratio of 30%, the volume of water entering the test
area was calculated to be 4.85 acre -ft.
Evaporation was calculated based on the guidance provided in the Colorado Department of
Natural Resources, Division of Water Resources "General Guidelines for Substitute Water
Supply Plans for Sand and Gravel Pits" (Guidelines). Map 3 in NOAA TR33 was used to
estimate a total of 40 inches of annual evaporation for the project site. That annual evaporation
was reduced for each month by the relative distribution recommended in section 11 of the
Guidelines, and then reduced to a daily value.
The seepage for the first phase of the testing was calculated to be 9.23 acre-feet. The seepage for
the second phase of the testing was calculated to be -1.19 acre-feet. The negative number is
indication that less water ran off into the test area than was allowed for in our calculations, and
should be considered as zero rather than negative for the purposes of this study. The total
infiltration for the 91 -day period was 9.37 acre-feet.
The allowable seepage for the reservoir was determined using the following procedure: The total
wall area was multiplied by the allowable wall seepage ((0.03 ft3/day/ft2) /43560 ft3/acre)
multiplied by the number of days of the test (91). This number is added to the result of the
reservoir floor surface area, within the repair area multiplied by the number of days of the test
(91) multiplied by the allowable floor seepage ((0.0015 ft3/day/ft2)/43560 ft3/acre). The
performance standard is three times the design standard. The allowable seepage for the design
and performance standard was calculated and compared to the seepage calculated through the
mass balance equation. The surface area of the floor was 576,657 ft-. The allowable seepage
volume through the floor is calculated to be 1.81 acre -ft. The 3-D surface area of the reservoir
walls was 206,205 ft2. The allowable seepage volume through the wall is calculated to be 12.92
acre -ft. The calculated total allowable seepage for the design standard is 14.73 acre -ft, and the
calculated total allowable seepage for the performance standard is 44.19 acre -ft. The allowable
seepage for the 66 -day first phase of the study was calculated to be 10.68 acre -ft for the design
standard and 32.05 acre -ft for the performance standard. The reservoir performed within the
design standard for seepage into a reservoir for each individual phase of the study as well as the
entire study. A copy of the calculations is included as an attachment to this letter.