LOWELL – An Essex County Sheriff’s Deputy was arraigned Monday after he allegedly purchased heroin from an undercover State Police Trooper, authorities said.John Bachta, 37, of 32 Glen St., Methuen, was arrested Saturday and charged with possession of a class A drug (heroin).According to a police report provided by the Middlesex District Attorney’s Office, Bachta was the subject of an undercover investigation prior to his arrest. He allegedly purchased two grams of heroin from an undercover officer in the parking lot of Home Depot on Route 38 in Tewksbury.Bachta is a 15-year veteran Deputy who reportedly gained the rank of Sergeant and is currently on unpaid administrative leave.Police said Bachta still had the bag of heroin in his hand and dropped it to the ground when officers were about to arrest him.Bachta was arraigned in Lowell District Court, where he was released on personal recognizance.Bachta is the son of retired Lawrence Deputy Police Chief Stanley Bachta, according to the Eagle Tribune newspaper.After Bachta’s arrest, police inventoried his vehicle and found numerous law enforcement-related items, including body armor, a fully loaded Sig Sauer P-229 handgun, two additional loaded pistol magazines, a black jacket that said “Lawrence P.D.” a black jacket that said “Police Gang Unit,” an orange police traffic vest, a Methuen police baseball bat and handcuffs – all of which were turned over to Gerald Mohan, Director of Internal Affairs at the Essex County House of Corrections.