that's right, but
I used about two gallons of Kleen strip instead, a Tyvek suit and long gloves, and used a pull down carbide scraper. As long as the area around your boat is covered "well" with tarp, the mess is gathered and disposed of correctly. I believe the law is on my side.
You can't leave the chemical on very long because it eats gelcoat, but on multiple layers the strippers only can melt about 3 layer at a cycle. I have done the keel area only the hull was previously barrier coated. I used the Inteprtect , about 1 gallon. This little project took about 20 hours, and the antifouling paint is not on the keel yet.
Note:The stripper dries very fast, you may have to recoat frequently to make it work. It will burn the skin, so you need fresh water to rinse yourself if you splash.