REP08380

• Permit No: C1980005
• IBM Index Class Name: Report
• Doc Date: 4/17/1995
• Doc Name: SENECA II MINE C-80-005 1994 ANNUAL HYDROLOGY REPORT
• From: DMG
• To: WALLY ERICKSON
• Permit Index Doc Type: HYDROLOGY REPORT
• Media Type: D
• Archive: No

III IIIIIIIIIIIII III
999
STATE OF COLORADO
DIVISION OF MINERALS AND GEOLOGY
Depanmenl o(Nalural Resources
1313 Sherman 51 ,Room ? I S
Denver, Colorado 80203
Phone: [phone]~356i
FAX: [phone]
DATE: April 17, 1995
TO: Wally Erickson ~
FROM: Susan Burgmaier ~7"
RE: Seneca II Mine (C-80-005)
1994 Annual Hydrology Report
~I~
DEPARTMENT OF
NATURAL
RESOURCES
Roy Romer
Governor
lames S. Lochhead
E><ecWive Director
Mirhael B. Long
Division Director
I have reviewed the surface water portion of the above mentioned hydrology report, and have
the following comments:
1. For the 1994 water year, 13.23 inches of precipitation was measured at the site. This
value is 3.61 inches below the 1961-1990 average. Snowpack runoff 5.89 inches) was 2.52
inches below the 1961-1990 average, and was the lowest since 198 .
2. Low precipitation at the site for 1994 appears to have had a significant impact on surface
water quality at all monitoring sites. Total Dissolved Solids (TDS) reached record highs
at a number of sites (SW-S2-6, SW-S2-10, NPDES 002, NPDES 603, and Spoil Springs
#1, #2, #5, and #9). All other sites exhibited elevated TDS values, but the values were
within their respective historic ranges.
3. CDOH stream standards for Segment 13B of the Yampa River (applies to the Fish Creek
Basin sites) were exceeded on a few occasions at various surface water monitoring sites.
Though some of the deviations were attributed to laboratory or sampling error high
values of cadmium, copper, chromium, fluoride, and nickel), the majority o the
deviations (sulfate and sulfides) can be attributed to low flow conditions.
4. Although surface water quality in 1994 was, for the most part, worse than that observed
in prior years, data indicate c)ualLry is still within predictions made in the Probable
Hydrologic Consequences section of the approved permit application package.
5. Based on this and previous years'.data, it would appear that the sharp decrease in quality
at the surface water monitoring sites is indicative of low flow conditions, and is not likely
a result of mining operations.
6. The narrative of the report indicates that the map of monitoring sites should be removed
form the 1993 AHR, and placed in the 1994 report. The map is the same as the 1993
map but if it is removed from the 1993 report, a person reviewing only the 1993 report
wou~d not have access to the map, nor would the 1993 report include a reference for the
location of the map. In the interest of facilitating public review of these reports, we
should request that Seneca Coal Company provide two additional maps for placement
in the 1994 reports.
I did not review monitoring frequency or adequacy, per Larry's request that the lead specialist
do that portion of the review. Barbara will be reviewing the groundwater information, as
indicated in our February 14, 1995 memo to the team. If you or the operator have questions
or need additional information regarding my comments, please let me know.
c: Larry Routten
si.n~oai~vs.wr
• •