The Quantico Town Council has received a second application for the job of town sergeant. But the council has taken no action to fill the position that has been vacant for most of the past 15 months.

Quantico Police Officer Leo Rodriguez submitted an application for the $ 12,750-a-year job, which involves heading Quantico's six-member police force. Rodriguez, a former Dumfries policeman, moved to Quantico this month so he would be eligible for the sergeant's job, which legally must go to a town resident, according to Mayor T. A. (Phil) Giannopoulos.

Rodriguez, who left the Dumfries police force last december, has worked as a Quantico patrolman since April.

The only other candidate for the job is former sergeant Richard A. Gabriel, who was dismissed in August 1980. Gabriel reapplied for the job, but the council has refused to reappoint him. In September, more than half the town's registered voters signed a petition asking the council to reappoint Gabriel.

Although the matter has been on the council's agenda for the past three months, the members have not discussed it. Councilman Herbert J. Saunders said he didn't want to act on the issue until more applicants are found for the job.

Giannopoulos said he expects the council to fill the position at its Dec. 10 meeting.