I would use a sod cutter to remove the turf. I have a property that has a dog run like you have described. They described before I was hired in that the previous company came in with a sod cutter and took out the grass and applied a vegatation killer, they then put down weed block felt and then installed pea gravel. I kinda wondered about the weed felt due to keeping the smell of urine, but they say there is no issues.
K&A Lawn Care & General Services
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