I grew up in Richmond CA. Probably a place you would not even stop for fuel.My hometown has often been described as rough, and some believe people are a product of their environment, I am a diamond in the rough.
That's why "flammability" was in quotesIts not really flammable though. You could keep it and use it for parts cleaning or engine degreasing i guess.
Then just strain it through a [used] P1 or P2 mask into your fuel tank.
diesel doesn't mix with gasoline too well and might cost engine hesitation. It will not damage the engine, but performance will drop.
Or don't create a contaminated piece of fabric and just dump it directly into a petrol can used for your lawn mower, or even into a petrol vehicle tank. It won't hurt anything either way. I've been running 50/1 gas oil mix from my 2 cycle outboard engine tanks in all of my small engines for decades now. My 4 cycle engines have never had any problems. The small quantity of filter diesel fuel is no problem.