Marfell was arrested on November 12, 2020.
Between October 2019 and November 2020 she was involved in supplying 540 grams of P.
She supplied 40 millilitres of liquid ecstasy over five occasions and offered to supply as much as 2000ml.
Overall Marfell had officially supplied 664g of P.
A search of her home uncovered nine 1-litre bottles of GBL as well as two 5-litre plastic fuel cans that had GBL residue.
Appearing before Justice Graham Lang via audio-visual link in the High Court at Hamilton today, Marfell admitted possession of P for supply and supplying P, participating in an organised criminal group, conspiring to deal methamphetamine and possessing and supplying GBL.
Justice Lang convicted Marfell - who choked back tears as she pleaded guilty to the 12 charges - and remanded her in custody for sentencing in September.
It's not the first time Marfell has faced drug-related charges in court.
In 2012 she was sentenced to 80 hours' community work for possession of class C drugs after an incident in November 2011 in which seven Fairfield College pupils were admitted to Waikato Hospital after they took the banned drug BZP and other controlled substances.
The party pills were found in Marfell's bag by her then 14-year-old daughter who took them to school and handed them out as ecstasy.
In 2009 she was fired from Affco after a random search found drugs in her car at work.
Marfell took a case for unfair dismissal to the Employment Relations Authority which found against her.
Additional reporting Belinda Feek.