I have tested pos for opiates 3 times in a methadone program. I only taken the methadone they gave me, how is this possible? I really haven't used

It's an opiate! Methadone (just like morphine, heroin, codeine, oxycodone, opium & hydromorphone) is an opiate. If you're CERTAIN your aren't ingesting any other opiate, then only methadone should show up on your drug tests. However, office based urine drug screens can give false positive results for other drugs. If there's any question, they should be followed up by a confirmation test.