Brush off as much as possible with a wisk broom or something similar. Then launder. Here is how.
I would try to scrape off as much as possible. Then use a commercial solvent to dissolve the tar. You could first try some Crisco. Rub in well and was with VERY hot water. Good luck.
Hello Karen! My husband worked at a coal fired electrical plant for many years. He was covered in coal dust every day and his clothes were always black with coal dust. I only washed his clothes alone with Tide-sometimes twice--to try and get all of the greasy dirt out. For the heavier stains I used Shout first. Most of the time his work clothes cleaned right up but sometimes the black coal residue was permanent in his lighter colored t-shirts around the neckline. Hopefully you only have a small amount to get out.