Parts of metro Phoenix are sinking due groundwater pumping before 1980.
Mine spill will dilute to safe levels before reaching Grand Canyon.
CAP is closely monitoring the situation and stepping up monitoring as a precautionary measure.
Many experts believe there is a 90 percent chance El Nino will stick around through next winter.
An El Nino winter might not end the ongoing drought, but it could supply water to the area.
Unlike central Arizona, most of the rural areas of the state do not have limits on pumping.
While predictions for this year's El Nino are big, it won't solve the drought.
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