Northern Virginia Rep. Stanford E. Parris provoked an angry reaction from some Fairfax County officials yesterday by sending letters questioning a proposed public housing project to about 40,000 residents of the Mount Vernon area.

Parris, who has intervened before to block unpopular housing projects in his district, this time questioned a project in the predominantly black community of Gum Springs, which has been supported by the immediate community but opposed by some surrounding, predominantly white neighborhoods. The letter stated that Parris, a Republican running for reelection, has not taken a stand on the 105-unit West Ford project, but it included mostly negative information about it.

Fairfax Supervisor Sandra L. Duckworth, a Democrat whose district includes Gum Springs, said the letter also contained inaccurate information. She said Parris overstated the project's costs and misstated the history of public hearings that have been held on the proposal.

"We're getting calls from people saying: 'We're going to have slums,' " Duckworth said. "This letter does not give enough information for innocent citizens who don't know the issue to make a judgment. It's very biased."

Duckworth and Supervisor James M. Scott, another Democrat and a strong public housing supporter, also accused Parris of using congressional franking privileges to send campaign literature.

"I have been representing the residents of Northern Virginia in county, state and federal government for over 18 years; and in that time, I have always believed that it was my duty as an elected official to represent with my voice and my vote not my own views, but the views of my constituents," the Parris letter stated in seeking constituent opinion. "I am proud to be your Representative in Congress."

An aide to Parris said the letter was approved by the House Franking Commission as a legitimate constituent service. The aide said Parris had received 300 letters opposing the project, which was approved by the Board of Supervisors last month, and about 40 or 50 supporting it. He said Parris wanted to find out whether the opposition was widespread.

The congressman's letter cites the project cost as $8.5 million, or an average of $81,000 for each two-to-four-bedroom town house. Walter Webdale, Fairfax housing director, said the actual cost has been cut to about $58,000 per town house. "We took the latest information HUD the federal Department of Housing and Urban Development had provided us," the Parris aide said. "If the figures have since been decreased, we will be delighted."

Fairfax officials have said the West Ford project will allow current residents to move out of dilapidated housing in Gum Springs, which began as the slave quarters for George Washington's plantation. Critics of the project have said it will encourage poor people to move to the area, rather than serving families who already live there.