Page 78 - Beaumont Basin Watermaster - 2015 Annual Report

secondary MCL of 200 ug/L. Aluminum above the MCL can add color to water. One well
exceeded the MCL during the FY 2004-08 reporting period.

Arsenic. There were 34 water samples collected and tested for arsenic during the reporting
period. The highest arsenic concentration was observed at SMWC’s Well No. 4; arsenic
concentration at this well has increased from 4.2 mg/L in 2009, to 4.6 mg/L in 2012, to the
highest value of 5.2 mg/L in April 2013. Latest value, recorded in April 2016, arsenic
concentration was down to 4.4 mg/L. One well exceeded the MCL during the FY 2004-08
reporting period.

Iron. A total of 33 water samples were taken during the reporting period and tested for iron. In
most cases iron concentration was below 100 ug/L., which is significantly below the current
secondary MCL of 300 ug/L. However, there are two wells that exceeded the MCL during the
2010-14 period; BCVWD Well No. 11 at 800 mg/L and BCVWD Well No. 20 at 450 mg/L in
December 2012. Iron concentration at BCVWD Well No. 11 decreased significantly to 340 mg/L in
August 2013. Iron at a concentration above the MCL can impact color, odor, and taste in water.
Five wells exceeded the MCL during the FY 2004-08 reporting period.

Lead. There were 33 water samples collected and tested for lead during the reporting period. The
highest concentration reported were 0.0065 mg/L at BCVWD Well No. 25 and 0.0058 mg/L at
Rancho Calimesa Mobile Home Park Well No. 1. Both of these concentrations are significantly
below the current primary MCL for Lead of 0.015 mg/L. Lead concentrations in water above the
MCL can have significant impacts on human health. One well exceeded the MCL during the FY
2004-08 reporting period.

Manganese. There were 33 water samples taken during the reporting period and tested for
Manganese. Manganese concentration at all wells was below 20 ug/L, significantly below the
secondary MCL of 50 ug/L. Manganese can significantly impact color and taste in water at
concentrations above the MCL. One monitoring well exceeded the MCL during the FY 2004-
08 reporting period.

Total Chromium. A total of 33 water samples were taken during the reporting period and tested
for total chromium. The highest reported concentrations of total chromium were observed in
February 2011 at Sharondale Mesa HOA Well No. 2 at 9.1 ug/L and in October 2013 at BCVWD
Well No. 3 at 11 ug/L. Both of these values are significantly below the current state primary MCL
of 50 ug/L. One well exceeded the state primary MCL during the FY 2004-08 reporting period.

Vanadium. Three water samples were tested for vanadium during the reporting period from
SMWC’s Well 4 and YVWD No. 48. Vanadium at the SMWC well increased significantly during
the reporting period from 17 ug/L in March 2010 to 84 ug/L in April 2013 and to 100 ug/L in April
2016. These two latest values exceed the state notification level of 50 ug/L. Vanadium
concentration at YVWD No. 48 was 25 ug/L, which is half the state notification level.

Copper. There were 33 water samples collected and tested for copper during the reporting
period. Over the last five years only one well has exceeded the detection limit of 50 ug/L; the
Rancho Calimesa Well No. 2 at 62 ug/L (Feb 2013). This concentration is significantly below the
state primary MCL of 1,000 ug/L. This is consistent with previous reporting periods.

Beaumont Basin Watermaster 2015 Annual Report – Final – December 2016 4-7