While it certainly sounds like the foliage may have been damaged by direct exposure, the roots will hopefully be less vulnerable and the compound can be leached from the soil (or at least diluted) before too much damage has occurred; this time of year, root and crown (the main growing points) health is more important than foliage health. Natural precipitation may be sufficient (especially given recent weather patterns), but if you are able, physically remove what you can from the surface of the pavement or mulch/soil with sweeping, leaf-blowing, and/or raking as needed. This will not only lessen exposure of the soil but also reduce how much runs-off as groundwater pollution. Packera aurea is fortunately a quite vigorous native species and should re-colonize any salt-killed areas fairly quickly.

Here is our page on salt damage in the landscape. Fertilizer, while not applicable to your situation here, is included on this page because fertilizer minerals are a type of "salt." https://extension.umd.edu/hgic/topics/saltfertilizer-damage (Note: the mention of gypsum for rock salt is as a mitigation for sodium specifically, which isn't what the county used and so may not be useful.) There is a link at the bottom of that page that will take you to our soil testing page, which contains a list of some area labs. It's probably best to wait a while (maybe a couple of months) before sending a sample out for testing so dilution, leaching, and natural biochemical soil processes have a chance to lower the salt levels.

Miri

Dear Miri,

You're welcome!