(AP) - California officials are spending $1 million to protect a 99-year-old dam in Northern California that could collapse if a big rainstorm hits this winter.
KCRA-TV reports that the concrete dam in Jackson was built in 1916 and holds back large quantities of arsenic-contaminated tailings left over from gold mining.
In June, the U.S. Army Corps of Engineers found that the dam was structurally unsound.
The California Department of Toxic Substance Control has begun a $1 million emergency operation to build a system for diverting storm water around the dam. It should be completed this month.
The city of Jackson says the National Weather Service will issue a warning if rainfall amounts reach certain levels that could exacerbate the dam's structural problems.