The following were among actions taken at the July 20 meeting of the Fairfax County Board of Supervisors. For more information, call 691-3187.

CENTREVILLE DEVELOPMENT -- The board voted 6 to 0 to approve the $400 million, 100-acre Trinity Centre Project, capping more than a year of negotiations between the project's primary developer and Centreville citizens groups.

The project will be located west of Rt. 28 between Rt. 29 and I-66 in a largely undeveloped rural section of the county. Plans for the development call for nine office buildings, a 300-room hotel, 764 garden apartments, a movie theater, an outdoor entertainment area and a three-acre lake with surrounding pathways.

The final plans approved by the board were developed after intense negotiations with Centreville civic groups and Cadillac-Fairview Co.. As part of its attempt to get citizen approval, the company added $17.5 million in road improvements to the plans, including the designof an interchange at the intersection of Rts. 28 and 29. The developer also agreed to reserve 10 percent of the 764 apartments for low- to moderate-income families.

Cadillac-Fairview also agreed to build the project in phases so that no more than half of it is constructed over the next six years before a new interchange is constructed at Rt. 29 and I-66.

LOW-INCOME HOUSING -- The board voted 5 to 0 to approve the construction of 30 low- and moderate-income town house units as part of the Reston Town Center project.

The $2.1 million project, which will bring to 96 the number of public housing units in Reston, received strong support among Reston citizens groups and churches.

Nearly 30 people attended a two-hour public hearing on the project, many of them arguing that other areas of Fairfax County should encourage the creation of affordable housing units in their communities.

Janet Howell, former president of the Reston Community Association, said she was proud of her community for its support of affordable housing units and group homes and a homeless shelter. But Howell said she also felt "tremendous loneliness," because other communities were not so forthcoming in their support for these types of programs.

Many at the hearing argued that the 30 units were only a beginning and that the county needed to take more steps to create housing units to allow rank-and-file county workers to live in the county.

The three-bedroom town houses, to cost $71,000 each, will be built with federal funds on 2.9 acres donated by the Reston Land Corp.. The units will be located at the northeast corner of the intersection of Town Center Parkway and Bowman Towne Drive.

FAIR OAKS LIBRARY -- The board approved $56,000 for the reopening of a mini-library at Fair Oaks Mall, which was closed in January when its space was reclaimed by the county for other uses.

The library had operated at the mall since 1980.

The Taubman Corp. recently offered the county library system new space in the mall, and the county agreed to reopen the popular facility.