Kent Gammon, who heads the independent three-member panel, told Reuters that the 29-year-old Livermore had returned the positive result in an out-of-competition test on Dec. 16.
Livermore, who could face a four-year ban, declined to comment on Gammon's statement when contacted by Reuters.
Gammon would not name the alleged banned substance but said Livermore had violated Article 2.1 of the Jamaica Anti-Doping Commission's (JADCO's) rules, which refer to the "Presence of a prohibited substance or its metabolites or markers in an athlete's sample".
Livermore, who also won gold at the 2014 Commonwealth Games in the 4x100m with Usain Bolt, Kemar Bailey-Cole and Nickel Ashmeade, had a preliminary hearing on Friday in front of the disciplinary panel at the Jamaica Conference Centre.
He will start the fight to clear his name at a full hearing on Sept. 11 to be attended by JADCO and his representatives.
Sources close to the case told Reuters Livermore had not asked for his 'B' sample to be tested. Livermore declined to comment when asked by Reuters if he had requested such a test.
Livermore, a 200m semi-finalist at the 2013 world championships in Moscow, did not compete at Jamaica's senior trials last month and will not be part of the national team at the worlds being held in London next month.
Livermore, who has a personal best of 10.03 seconds in the 100m and 20.13 in the 200m, was also a member of Jamaica's gold-medal winning 4x200m team at the World Relays in 2015.
(The story makes clear the anti-doping panel is not part of JADCO)
(Editing by Ken Ferris)
