The Bradley-Arlington Office Center was completed last week, six months behind schedule. The delay in finishing the 109,000-square-foot structure occurred because it took more time than anticipated to blast through solid rock at the site, according to Joel Fernebach, president of Harvey Cos., the developer.

The rock deposit was approximately 20 feet deep, and the blasting cost about $500,000, he said.

The building is 93 percent leased and 40 percent occupied, he said. A number of the tenants are relocating from other sites in the Bethesda-Chevy Chase area, including Kaufman, Rosenbloom & Shapiro, an accounting firm, and the National Association of Surety Bond Producers. Other tenants are Massachusetts Mutual Life Insurance Co., Technassociates, architects, attorneys and doctors.

The $12 million, five-story building is connected to a 250,000-square-foot garage.

Other recent developments in commercial realty in the Washington metropolitan area:

Strategic Planning Associates Inc., a management consulting firm, leased 48,000 square feet at 2300 N St. NW. The 10-year lease has an aggregate value of $15 million.

Mutual of Omaha, an insurance company, has leased an additional 25,000 square feet at 2094 Gaither Rd., Gaithersburg. It now occupies all 56,000 square feet of the leasing space at that location.

Ellerbe Associates, an architectural firm, leased 18,400 square feet of space at the National Press Building, 529 14th St. NW. The 10-year lease has an aggregate value of $2.3 million.

Sysorex Information Systems Inc. leased 16,172 square feet at 3 Skyline Place, Skyline City.

Cincom Systems, a software manufacturer, leased 14,000 square feet at Oakton Corporate Center III, 10467 White Granite Dr., Oakton.

American Systems Engineering leased 10,159 square feet at Two Crystal Park, Crystal City.

Verlan Ltd., an insurance company for the paint and coatings industry, leaed 6,764 square feet of space for 10 years at 1615 L St. NW.

Wagner & Barody, a public relations firm, leased 5,744 square feet at 1615 L St. NW for six years.

The National Prison Project, a part of the American Civil Liberties Union, leased 5,000 square feet at 1616 P St. NW.

Cities in Schools, a nonprofit brokerage of private and public partnerships related to the school drop-out problem, leased 4,463 square feet at 1023 15th St. NW.

The National Alliance for the Mentally Ill subleased 4,000 square feet from Informatees Inc. at 1901 N. Fort Myer Dr., Arlington. The aggregate value of the lease exceeded $300,000. The length of the lease was not disclosed.

Beard Warwick Cornell Associates, an architectural firm, leased 3,845 square feet at 1615 L St. NW for four years.

Art Konopka leased 3,700 square feet at 1 Thomas Circle.

CBN News, a subsidiary of the Christian Broadcast Network, leased 3,700 square feet at 1301 Pennsylvania Ave. NW. The aggregate value of the lease is $400,000. The length of the lease was not disclosed.

The Inlingual School of Languages leased 3,200 square feet at 1030 L St. NW

Wilcoxon Research Inc. leased 3,000 square feet at 2096 Gaither Rd., Gaithersburg, bringing its total of leased space at that location to 12,000 square feet.

Tandy Corp. leased 2,500 square feet at 2096 Gaither Rd., Gaithersburg, to house regional offices.