I recently removed a Pine tree from my yard because the roots ruined my driveway and sidewalks, I want to plant and install irrigation but the roots are huge and I and having a hard time romoving them. I tried a small chainsaw and it kept getting dull I used a sawsill which worked on the smaller diameter roots but the big ones next to the stump seem impossible to get out. Is there a chemical I can us or another type of cutter I can use.

A stump grinder is the best answer,takes your stump and roots down to a workable depth. we mainly deal with cherry trees for grinding roots, normally you have a "main" cherry root running away from the stump.i dont know how much it would be to hire a stump grinder and operator where you are but here in yorkshire, england prices would start at around 40-50 pounds sterling-in usa i reckon you could get it done for $100 or so!?
i hear that in china they used to have a chain that they would put on an old bent guide bar and bore into the ground to cut roots!
The cheapest way is the oldest way......get a good spade and an axe n hack em out.
ive found that chemicals dont really speed up natural decay that much.
At least if its a pine tree it wont grow back!
good luck-if you go for the cheap option then its a good job for a cold winters day, will keep you warm.