Being a Washington State Trooper/Cop if i smoked weed before ;(?

Hey, I'm 26 and i live in Puyallup Washington. I have smoked weed 20-30 times and I went to college and played football, which ment a lot of drinking too. I dont drink neer as often as I did in college. Smoking weed was out of the wuestion, or so I thought. Recently i went to the UW vs USC football game and did some tailgating with some old friends. I had about 10 beers and I did smoke weed. I know it was a bad choice and pretty sure the beer didnt help. I really want to get involved in helping the community and being a officer would be a goal I would like to achieve, Puyallup PD, Tacoma PD or Seattle PD ect. I have a buddy thats a State Trooper and he said as long as I'm honest it doesnt matter. But i checked out the website and it says you cant become a cop if you've smoked in the last 3 years? Anybody have any good info for me?