Quote Originally Posted by Burnt Toast
It means that the results were reported to your employer.

Give the employer a call and ask for your "start date". The employers response oughta shed some light on whether youre good to go, or if the employer had moved on to the next applicant for hire.

Never inquire about the test results! A person who is truly drug-free would never do this because, being drug-free, theres no reason to do so. Inquiring about the results would only serve to raise suspicious eyebrows.
Youd want to assume the "I dont use drugs, therefore my drug test is a non-issue" mindset. You would be notified one way or another if there was a problem with the urine sample.

My employer already knows the day I plan on starting (assuming I pass the drug test of course) so I can't call and ask that. What would be the next best thing to say to them?

I was thinking of just emailing her (since that is the way 90% of the communication between us has been) and saying:

"Good afternoon,
I took my pre-placement drug test last Friday, so I should be all set to start working on May 20th. Is there any paperwork I need to fill out prior to the start date?"