The Fairfax County School Board last night approved its second elementary school closing in less than a month and voted to begin procedures for shutting down a third school because of declining school enrollment.

The board voted to consolidate Virginia Hills Elementary School into Rose Hill Elementary at the request of neighborhood parents.

School staff recommendations to begin a consolidation study involving Camelot, Mantua and Pine Ridge elementary schools then encountered vehement protests from parents.

The board voted 6 to 1 to begin that study, with board member Tony M. Carney casting the only dissenting vote and pressing for a one-year delay in consolidating the schools.

"A vote for this consolidation study is a direct vote to close Pine Ridge Elementary," charged Philip Schneider, a parent of children at the school. "And it is a vote for overcrowding in the other two schools." Parents argued that Pine Ridge would be closed because it could not handle the additional load of students from another school.

The school board has shut down 16 elementary schools in the past nine years, including two closings this school year. Last month the board voted to consolidate Lewinsville Elementary into Kent Gardens Elementary in McLean, also a voluntary merger at the request of parents.

Although Fairfax County, with 123,780 students, has the largest school system in the Washington area, officials estimate that enrollment will drop by about 2,350 over the next two years, forcing the system to consider even more closings. School staff figures indicate that at least 26 of the county's 120 elementary schools are overstaffed and operating with too few students.