MUSCATINE — The use of slag on Muscatine County gravel roads has been suspended indefinitely.
"There was some indication from some of that information presented that there may indeed be a health hazard," Supervisor Nathan Mather said at Monday's board of supervisors meeting. "We're still awaiting more results. That said, I've asked to put on the agenda a motion to or a possibility of indefinitely suspending the use of slag pending the results of this further testing so that we know what we're dealing with."
Mather said according to the county engineer, the by-product of the steelmaking process has not been used on the roads since June. The board is waiting for more information about the material before deciding its next steps.
Attempts to reach members of the residents' slag committee before deadline were unsuccessful.
Statements Harsco, the county's slag supplier, issued to the board were released Tuesday to the public.
Glenn Hundertmark, North American environmental manager at Harsco, said in his statement, “My request is that, due to the availability of additional information that is very relevant to the health analysis, that additional time be allowed to provide the board with more accurate, factual information prior to you making any decision because I fear that at this time, you have only heard part of the story.”
He went on to say, “We are urgently working to provide relevant, factual, scientific data to the county and to IDNR/IDPH (Iowa Department of Natural Resources/Iowa Department of Public Health) to assure you and the community that there are no health or environmental risks associated with this road material. We believe that any claims otherwise are completely meritless and based on mischaracterized, misinterpreted data.”
Hundertmark said joint samples were taken last week with the Iowa DNR of the slag aggregate used on county roads and results of the testing would be shared with Iowa DNR “shortly.” When results are available from Iowa DNR, Hundertmark said, a presentation would be made before the board, and he expects analytical results from testing “by the end of the week.”
“Most importantly, as far as this latest testing is concerned, we expect manganese levels to be well within acceptable health and environmental ranges,” he said.
According to a report sent to Edward Askew, a resident who has been unofficially advising the board on slag testing, the concentration of manganese in the slag may be harmful to children.
"After reviewing the information that you provided on the slag that is being deposited on roads in Muscatine County," wrote Stuart Schmitz, state toxicologist, in an email to Askew, "I would conclude that children living and playing in areas where the slag was deposited could experience adverse health impacts from the manganese within the slag." He said the health impacts could potentially be more severe for children displaying pica behavior, or eating the slag.
In his statement, North American sales manager for Harsco Peter Mazzarella said, “We have over 100 years of experience developing and manufacturing construction aggregates from steelmaking slags. Our slag products are used all over the world — in more than 30 countries — in numerous applications.”
He continued, “We market approximately six million tons of slag per year worldwide, and there has not been a single instance where it made anyone sick or was considered a health or environmental hazard.”
He said the company continually assesses the environmental impact of its operating facilities and products and “we take actions to eliminate unacceptable risks to the communities in which we operate — to our neighbors, our employees and our customers.”
Mazzarella also made a request for more time to gather information for the board before it voted on using slag including the analysis of the samples of the aggregate taken with the Iowa DNR, other results from samples taken in recent years that show manganese levels are “in acceptable ranges for people’s health and safety and also as far as the impact on the environment is concerned.”
He said the company would also provide an assessment of a health analysis provided to supervisors and have experts from the National Slag Association share an independent risk assessment report.
“For all these reasons,” he wrote, “we are requesting that you provide us with more time and delay any vote on this until all information is available. We are not asking you not to vote, we are just asking you for a little more time before you vote.”
The motion to suspend the use of slag was made by Supervisor Jeff Sorensen and was seconded by Supervisor Scott Sauer. The motion passed with all ayes.
"Simply put, we suspended the use of slag out of an abundance of caution while more information is gathered," Mather said.