Big fire in Maryland?

Last Thursday at 10:30-11:00 am I was travelling north on Rt 113 from Chincoteague, Va. to Assateague, Maryland. In the distant northwest here was a huge plume of black smoke. I checked local news sites via Google and couldn’t find anything. Does anyone have any idea about what was burning? A controlled burn, maybe? We have those where I live but this smoke was very black, like a fuel fire or something. .

Possibly this fire in Ashburn, VA?

Or this one on Mt Airy,


The Ashburn fire fits the time and direction but, at 160 miles away, I doubt that was it. Oh, well it remains a mystery.