New York (CNN) -- The mother of two would often drive back and forth between her suburban Scarsdale, New York, home and the bleak-looking, one-story brick warehouse in Queens. Sometimes, she drove the route in her Mercedes SUV. She probably thought about her girls, 3 and 13. Maybe she was thinking of the horseback riding lessons with her teenager, and the new horse they were hoping to buy.
One thing perhaps not on her mind was being arrested and accused of living a double life: as a suburban mom and also as head of a multimillion-dollar marijuana growing operation. She faces federal narcotics charges.
Federal authorities say Andrea Sanderlin, 45, ran the marijuana operation from the warehouse, where they found two rooms packed with more than 1,000 marijuana plants and large amounts of dried marijuana, along with state-of-the-art lighting, irrigation, and ventilation systems to facilitate the hydroponic growing of the plants, according to court documents.
"The warehouse was filled with over $3 million worth of hydroponic marijuana and the organization covertly produced 3,000 marijuana plants," Brian Crowell, special agent in charge at the Drug Enforcement Administration, said in a statement Tuesday. When agents raided Sanderlin's home on May 20, they found books on how to grow marijuana and how to launder money, according to the DEA.
Details of Sanderlin's involvement in the case were first reported by The Smoking Gun website.
Sanderlin was arrested the same day, after agents followed her to the warehouse and entered on a warrant, court documents say. She is charged with narcotics trafficking, a felony that carries a maximum sentence of 10 years.
Sanderlin has pleaded not guilty and remains in custody pending a bond hearing.
She is a "full-time mom," attorney Joel Winograd said of his client, and added she is "very concerned" about her girls.
Originally from Virginia, Sanderlin was living in the upscale neighborhood of Scarsdale and driving a 2010 Mercedes SUV. According to court documents, she also had a 2004 Jeep Liberty and a 2005 Chevrolet van registered in her name.
Sanderlin had recently picked up the sport of horseback riding and took lessons with her teenage daughter at Twin Lakes Farm, a riding academy and competitive show stable in Bronxville, according to owner Scott Tarter.
Tarter described Sanderlin as a "beginner adult rider" who came to the academy in January after buying a Friesian horse for recreational riding. Tarter said on Tuesday that Sanderlin seemed like a normal, caring, local mother who boarded her horse at his stables.
Tarter said he thought Sanderlin was in the interior design business.
"She was just like all the local moms here," he said. "She wasn't loud. I never saw her smoking or drinking or anything that would have made me believe this."
Sanderlin participated in small horse shows at Twin Lakes, but decided to sell her horse in April. Tarter said they had planned to start looking for a new horse for Sanderlin but he hadn't seen her or her daughter since late May.
Authorities said a confidential witness tipped them off to Sanderlin's alleged crimes. The witness, who has been charged with participating in a conspiracy to possess and distribute marijuana, told investigators in April that a person named "Andi" operated at least one marijuana grow house in Brooklyn or Queens, according to court documents.
The witness also said "Andi" lived in Scarsdale and drove a Mercedes SUV, officials said. Later, when shown a picture of Andrea Sanderlin, the witness positively identified Sanderlin as "Andi."
Law enforcement agents said they contacted Con Edison about electricity accounts under Sanderlin's name. The electricity company told them about an account connected to Sanderlin's telephone number in the name of "Fantastic Enterprises" in Queens, at a location that was using "an unusually high amount of electricity."
Con Edison also said bills for the account were paid in cash.
Officials found that Fantastic Enterprises was a registered New York corporation from 2007 to 2011 and that the address provided for the business was an address listed under Sanderlin's name in insurance claims.