REP38526

• Permit No: C1992081
• IBM Index Class Name: Report
• Doc Date: 2/15/2002
• Doc Name: 2001 AHR Letter & Report
• From: Montgomery Watson Harza
• To: DMG
• Annual Report Year: 2001
• Permit Index Doc Type: Hydrology Report
• Media Type: D
• Archive: No

February 2002 Hoyden Gulcb Terminal, Inc * 2001 Annua/ Hydrology RepoK 1 Page 4
values. The dissolved iron (0.12 mg/I) and potassium (8.9 mg/I) in the October sample were higher
than previously observed values. The only constituents in the samples collected at HGSD3 with
concentrations outside previously observed ranges were aluminum (0.09 mg/f) and total iron (0.21
mg/1). Both of these values are new minimum concentrations.
HGTI has compiled a list of water quality standards for livestock. This list is composed primarily of
Colorado Department of Public Health and Environment (CDPHE) standards, although other
regulatory agency standards were used if the}' were more stringent or if CDPHE has no standazd for a
particular constituent. Table 4, Campanron oJ2001 Surface WaterQuaGty to LJvertock S[andardr, provides a
list of the livestock standazds along with a compazison of those standards to 2001 surface water quality
data. Units of concentration are as listed in Table 4. Laboratory analytical reports generally report
constituent concentrations as mg/l. The following constituents exceeded their respective standazd:
• manganese (standard of 200 µg/l):
HGSDI on 5/21/01 (210 µg/I) and 10/21/01 (360 µg/1)
• selenium (standard of 20 µg/1):
HGSDI on 5/21/01 (33 µg/1)
HGSD2 on 5/21/01 (42 µg/I)
• total dissolved solids (2500 mg/1):
HGSD1 on 5/21/01 (2700 mg/l)
HGSD3 on 5/21/01 (3080 mg/I)
V/hile these values were greater than their respective criteria, they are all within previously reported
ranges. As seen in Appendix C, exceedances of their respective criterion by these constituents is quite
common at both monitoring locations, especially during spring mnoff conditions.
3.3 GROUNDWATER DATA
Groundwater data for 2001 is presented in Appendix D, GmundvaterQuality Data. Presently, HGTI is
only monitoring alluvial groundwater in monitoring well HGDAL3. In 1993, HGTI installed
HGDAL3 as a new downdip alluvial monitoring well in response to Colorado Division of Minerals
and Geology (CDMG) concerns that the hvo existing alluvial wells, HGDALl and HGDAL2, may
have been partially completed in the Lewis Shale. Groundwater quality data was collected from
monitoring wells HGDALl and HGDAL2 between 1987 and 1995. Groundwater monitoring ceased
for HGDALl and HGDAL2 in 1995. The location of the groundwater monitoring wells aze shown of
Figure 1, Mouitaring Site Lacatiou Map. HGTI reported in the existing, valid Mining and Reclamation
Permit (revision date of May 1998) that chemistry information obtained in HGDAL3 is similaz to the
historic chemistry depicted by monitoring wells HGDALl and HGDAL2.
In general, the 2001 groundwater quality data from HGDAL3 is similar to previously observed values.
The boron concentration in October (0.87 mg/1) is slightly higher than the previously reported
maximum value of 0.80 mg/1. The potassium value in October (13 mg/l) is also slightly higher than
the previously highest reported value (] 2 mg/I). A comparison of 2001 groundwater quality data from
monitoring well HGDAL3 against the historic data indicates that water quality parameters were within
the range of historic values reported at HGDALI and HGDAL2. Historic water quahty data for
HGDALI and HGDAL2 are also presented in Appendix D.
Montgomery Wattan * P.O. Box 7ia018 * Steamboat Springs, CO 80477 * (970) 87%2G0
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