John J. O'Grady, the Fairfax County man accused of extorting $50,000 from a Northern Virginia banker in a kidnaping plot, was indicted by an Arlington County grand jury yesterday on additional charges of abducting and robbing the businessman's 19-year-old daughter and another woman last month.

O'Grady, 33, was named in the new indictments shortly after he appeared in a U.S. magistrate's office in Alexandria to answer charges that he extorted the funds from Milton Lee Drewer, president of First American Bank of Virginia in return for a promise to release the banker's daughter unharmed.

At the end of the one-hour hearing, magistrate Harris S. Grimsely directed that the unemployed O'Grady should remain in jail under $1 million bail for action by a federal grand jury.

The Arlington charges handed up yesterday allege that O'Grady forced Carol Lynn Drewer to cash four checks on her account at four local banks during her abduction Sept 23. FBI officials have alleged that during the course of her 14-hour abduction her kidnaper was negotiating with her father for a $50,000 ransom, which the banker paid.

In addition to the charges involving the banker's daughter, O'Grady was charged yesterday with the abduction of a second woman, whom federal investigators have said that O'Grady assulted previously during an earlier, unsuccessful attempt to abduct Carol Drewer.

O'Grady could be sentenced to 20 years to life on the Drewer abduction charge, five years to life on each of the four robbery charges, and four more years in Virginia prisons on charges of using a firearm in the commission of a felony, according to Arlington prosecutor Henry Hudson.

O'Grady also could receive 20 years to life for the alleged abduction of the second woman, Hudson said. Federal investigators have said that the 26-year old woman, a student nurse, was sexually assaulted and then forced to feign illness before she was released during O'Grady's first attempt to capture Drewer.

O'Grady, a curly-haired man who told a magistrate in San Francisco after his arrest that he was heavily in debt, did not testify yesterday. He wore a blue windbreaker, black pants, and tan cowboy boots to the hearing. Afterwards he was led away in handcuffs clutching a paperback book.

O'Grady allegedly kidnaped Drewer as she left her car at the bank's parking lot the morning of Sept. 23. The FBI has stated in court papers that he then demanded $50,000 from her father in exchange for her release. The money, mostly in $50 and $100 bills, was paid by her father that same day in exchange for her release, according to court papers.

As Milton Drewer drove from point to point at O'Grady's instructions before delivering the money, Drewer kept FBI agents informed of his actions by using a telephone in his car, an FBI agent testified yesterday. O'Grady was arrested four days after the abduction in a $90-a-day room at the Fairmont Hotel in San Francisco.