Good job on making it through the interview and getting your road test. I had a call back the next day to come back in, during that meeting I was made a job offer which was contingent upon me passing the DOT physical and drug screen. After they make you an offer you will fill out more paperwork for a back round check then head down to the clinic for your DOT physical and drug screen if that goes well you should hear back within a couple of days depending on how fast Bentonville is processing paperwork. Let me give you a little advice on filling out your background paperwork, you must be honest and make sure everything is in order. We had one guy that was eliminated right before orientation because of false statements somewhere in his application that were picked up during his background check. If your dirty or plan on falsifying any part of the background paperwork don't bother because they will find out. Remember the word integrity it goes a long way here and one or two minor "issues" will not necessarily mean your done. You have made it this far because the like you and think your a good fit so just be honest and you will be fine.
I drove down to CA had my interview on Monday a call back on Tuesday and was headed back to WA with my offer on Friday. I received a call on Wednesday of the next week letting me know I was cleared to start orientation. Be patient, your DC may be a little slower at getting things done but you are very close and you should hear something soon. I can tell you that a there were several people out of the twenty that interviewed with me that did not pass the road test so if you passed I would think its only a matter of time once again be patient.