2008-02-20_REPORT - C1980001

• Permit No: C1980001
• IBM Index Class Name: REPORT
• Doc Date: 2/20/2008
• Doc Name: 2007 Annual Hydrology Report
• From: WWC Engineering
• To: DRMS
• Annual Report Year: 2007
• Permit Index Doc Type: Hydrology Report
• Media Type: D
• Archive: No

' lowest sulfate bicarbonate ratio in 2007 was recorded at monitoring site TR-A in July with a
value of 0.09 SO4 (meq)/HCO3 (meq) and the high was recorded at monitoring site TR-C in
' April with a value of 5.25 SO4 (meq)/HCO3 (meq).
3.3.8 Surface Water Manganese
Chart 13 shows manganese concentrations for monitoring sites TR-A, TR-B, TR-C
and TR-D for the period of record. Manganese shows fairly consistent values since 1989.
Most of the manganese values observed are consistent with baseline values. Manganese
values appear to be developing a trend, which may be directly related to flow in Trout Creek
as are the TDS concentrations. Sampling in October of 2005, at site TR-D, produced an
inconsistent spike of manganese up to 0.248 mg/L. Manganese remained within historical
levels at all other sites along Trout Creek in October 2005. The October water quality data
was re-analyzed and the original values were confirmed. There is no apparent reason for this
sudden rise in value.
' Site TR-D normalized over the last few years, regarding the October 2005 spike, and
concentrations on average for all sites are low in comparison with the past decade. The
concentration trend seemed to have reversed during 2006 with higher concentrations resulting
' during low flow in Trout Creek, however the 2007 values fall back to the expected trend of
decreasing concentrations according to flow. The lowest manganese concentration in 2007
was recorded at monitoring site TR-A in April with a value of <0.01 mg/L and the high was
' recorded at monitoring site TR-D in April and July with a value of 0.06 mg/L.
3.3.9 Surface Water Aluminum
Chart 14 shows aluminum concentrations for monitoring sites TR-A, TR-B, TR-C and
TR-D for the period of record. Aluminum concentrations have been low with most being
below detection limits throughout the duration of monitoring. The apparent elevated
aluminum levels shown in 1995 were due to the laboratory lower detection limit being set at
0.2 ppm instead of 0.05 ppm. Aluminum was elevated at TR-C during the April 2002
sampling period. However, concentrations downstream of TR-C are consistent with previous
sampling results. Therefore, either 'sample contamination or laboratory error is suspected.
Aluminum was slightly elevated during the 2004 and 2005 sampling periods. The 2006 and
2007 sampling periods show consistent sampling results with the past decade. The lowest
aluminum concentration in 2007 was' the lower detection limit of <0.03 mg/L at all sites for
' numerous months and the high was recorded at monitoring site TR-D in April with a value of
0.06 mg/L.
' 3.3.10 Surface Water Unionized Ammonia
Chart 15 shows unionized ammonia concentrations for monitoring sites TR-A, TR-B,
TR-C and TR-D for the period of record. Unionized ammonia concentrations have been
consistently below detection limits. The unionized ammonia concentration appeared to drop
for the 1997 through 1999 monitoring periods due to the laboratory lowering the detection
i