2014-05-30_REPORT - C1994082

• Permit No: C1994082
• IBM Index Class Name: Report
• Doc Date: 5/30/2014
• From: DRMS
• To: Seneca Coal Company
• Annual Report Year: 2013
• Permit Index Doc Type: Hydrology Report
• Email Name: JHB
• Email Name: DIH
• Media Type: D
• Archive: No

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soils, as found throughout the Youast and Seneca II W region,
the EPA standard would be 10 mg /1. The maximum
manganese value observed at any surface site was .891 mg /1.
NPDES Outfall 013 exceeded the potential dissolved chronic
standard on April 19th (8.5 ug /1) and May 2nd (17.2 ug /1).
The exceedance for selenium is discussed under number 9
below.
9. Instream Numeric
CWQCC regulation 33.0
Ten monitoring sites exist within the Sage and Grassy Creek
Standards
Basins: YSSF3, NPDES 12, NPDES 13, NPDES 14, and YSS2 are
on Sage Creek. NPDES 10, NPDES 11, YSGFS, and YSG5 are on
Grassy Creek. In addition, Spoil Springs YSSPG3, YSSPG4, and
YSSPGS are found within the Sage Creek Basin and Spoil
Springs YSSPGI and YSSPG2 are found within the Grassy
Creek /Annand Draw Basin. The receiving stream standards
for both Sage Creek and Grassy Creek is on Segment 13e of
the Yampa River basin. The stream standards for Sage Creek
and Grassy Creek are based on aquatic life standards. Table
13 of the 2013 AHR provides a comparision of the standards
to water quality collectedfrom NPDES points and stream sites
in the Sage and Grassy Creek Basins. The total recoverable
iron standard (1.0 mg /1) was exceeded six times at five sites,
with one NPDES exceedance for iron occurring during the
2013 water year at Outfall 011.
The pH standard of 6.5 -9.0 was exceeded in May at NPDES13
(9.53 pH).
A high level mercury test with a method detection limit of 0.2
ug /I for streams and a low level mercury test with a method
detection limit of 0.0002 ug /I for NPDES sites was run. All
high level test values were less than the detection limit and
NPDES 011 exceeded the 0.01 ug /I mecury aquatic life stream
standard with a value of 0.013 ug /1. No previous exceedances
were reported for mercury for site NPDES 011.
Lower Grassy Creek Site YSG5 exceeded the potentially
dissolved chronic standard, 4.6 ug /I on April 29th of 2013 with
a value of 4.9 ug /1. NPDES Outfall 013 exceeded the potential
dissolved chronic standard on April 19th (8.5 ug /1) and May
2nd (17.2 ug /1). The selenium lab test were in three forms in
2013 in order to conduct an investigation on the difference in
three methods, dissolved, potentially dissolved, and total
recoverable. It is noted that the selenium value at Sage Creek
Site YSS2 immediately downstream of Outfalls 012, 013, and
014 was 1.5 ug /I on May 2nd.
The two exceedances of the selenium stream standard were