need some help- landscapers opinion more than welcome

[hi-revs]

Beginning of this past spring i applied for a permit to remove a small tree on my property to have a one-step deck built over it.
i got the permit and being a diy job, i just cut the tree down at its base. left the stump. (F*cked up here!)
i finished the deck by the end of june.
now i can see the stump sprouting new greens.

I know i could take the boards off and dig out the stump, but heres the catch- every board was screwed on from the bottom to have a screw-less clean finish. And the stump is located towards the end of the deck. So to get to it, id have to literally remove half the deck!!! (For anyone not familiar with this process, it means getting down on my knees and elbows to remove 20 planks of wood with 16 screws holding down each plank. This is definitely not something i want to do or have time to do again)

So you see, its not as simple as un-nailing a few planks from the top to get in there.

Luckily there is about 0.5" gap between planks which i may benefit from.

Anyone know any legal chemicals i can use to kill the stump and roots?
I just dont want a tree to shoot up from under my deck that i worked my ass off to put together.
there must be some sort of chemical "safer" to use than bleech or gasoline or anything in that nature.

**i repeat, removing each plank to get to it is not a viable option!

[bluejays]

Use this all the time in the yard

strong enough to use as a stump killer

Roundup 32 oz. Concentrate Poison Ivy Plus Tough Brush Killer-5002310 at The Home Depot

[Puck Luck]

I would also suggest Roundup. If its possible, with a long drill bit, drill into the stump and make some holes so the roundup can soak into the live parts of the stump.
Like creating an open wound then adding in the poison

[hi-revs]

Thanks guys. I'll try the Roundup.
I've read about drilling into the stump, but unfortunately I don't have enough room to do this.

[Hondaracer]

just pour a shit load of salt on the stump, done