Recent water testing at the Salem R-80 School District revealed lead contamination, according to a statement released on Oct. 5 by the district. Those tests revealed that 62 out of 150 sample points were contaminated with lead above the action level of five parts per billion (5 ppb). According to the statement, the district immediately began implementing signage and other measures to denote that those sources should not be used for drinking water, or to wash dishes.
Now, with a second round of testing complete, a new statement has been released. According to the statement, the hydrant near the track is the only one that tested above the action level during the second round of tests.
According to the statement, the second round of testing was done in an attempt to determine where the lead content was coming from. The test used a flush method, which involved running the water for 30 seconds prior to collecting the sample. Some water sources were not re-tested, as it was determined that those sources were not being used for drinking water or food preparation. Signage has been placed at those locations to warn against consumption.
The statement outlines a remediation plan, recommended to the district by Get the Lead Out, LLC. For test points at or above the action level of 5 ppb, the water source should be secured, and use discontinued until remediated unless testing proves that flushing (running the water for 30 seconds) will allow it to reach a level below 5 ppb. The 59 testing points listed in the statement all indicated greater than 5 ppm during the initial draw sampling phase. Using the flush test method, 27 were retested, with some test points passing. According to the statement, this indicates that the supply lines are not contributing significant amounts of lead into the water, but rather, the issue may lie with the outlets themselves.
“This can be caused by several factors,” reads the statement. “Hardness of the water, corrosion of iron pipes, high pH, high alkalinity, high temperatures (water heaters), high corrosivity, and the specific gravity of the materials used in construction of the outlets. As lime scale builds up it can cause a bottleneck that traps corrosion particulate matter that then leaches into the water supply lines. Additionally, older faucets may have been manufactured before the lead/copper rule…”
The recommendation notes that flushing as a stand-alone method is not considered adequate remediation. However, some of the outlets are allowed to be used again, assuming a 3-5 minute flush is performed daily.
Other options for remediation include permanent signage that states that the outlet is non-potable and for handwashing only, removal or replacement of the outlet unit, or the installation of point-of-use filters. Sinks with aerators should be inspected to determine if there is any scale or buildup that might trap contaminants.
