Good Morning Elizabeth, 

Thank you for contacting the U of M Extension Service. 

We are volunteer Master Gardeners who answer yard and garden questions. I am not familar with all the soil/composting rules for the local municipalities. I did some online research and agree, Washington County does not accept soil. These rules are probably to avoid jumping worms: https://extension.umn.edu/identify-invasive-species/jumping-worms

I asked the question to our Master Gardener forum. One of the Master Gardeners suggested this: I also wonder if a local community garden would take it since it is potting soil and not a likely jumping worm issue. They could add it to their compost piles. Check with Washington County Master Gardeners. They can direct you to a nearby community garden.<personal data hidden>)

Another gardener suggested: 

No Washington County food scrap program does not take soil, rocks.<personal data hidden>).I wonder why she doesn’t reuse it. I mix half used potting soil with half new potting soil every year and my pots do really well. Just add some fertilizer and you are all set. The only reason I would not reuse it is if there is a disease concern.

Here is a link to possibly serilizing the soil to reuse: https://www.almanac.com/should-you-sterilize-your-soil#:~:text=Researchers%20at%20Colorado%20State%20University,%C2%B0F

If you find a compost facility that heats their compost to a temperature that will kill jumping worms, they will probably take the soil. 

Good Luck!