A 3:1 ratio is an indication that someone had been manipulating her T:E ratio to be within the allowable but 3 times the normal ratio (1:1).
Also found this:
The Tribunal noted that the IAAF had established that both of Slaney's specimens had been analyzed as having T/E ratios significantly higher than 6:1. The tribunal also observed that Slaney's longitudinal study revealed a previous T/E ratio high of 3:1; meaning that her present ratio, by the most modest of calculations, was more than three times greater than she had ever previously tested.
It's significant that Alberto had been sending his urine to Victor Conte in the 80s, but for what? Conte wasn't a doctor, nor was he a scientist. He was a drug dealer.
It's also notable that Marion Jones, like Alberto, also a BALCO client, was sending her urine/blood samples to Conte to be evaluated at Quest Diagnostics for T:E ratios. There is no known medical purpose for T:E ratio testing. There is a known purpose for testing T:E ratios if you are a dpoer planning on compteting in track and field.