The chairman of the Fairfax County Board of Supervisors’ audit committee sent a curt note to a colleague who had called for an audit of the Fairfax-Falls Church Community Services Board, saying that one of the county’s watchdogs has already conducted one.

Supervisor John W. Foust (D-Dranesville) also suggested that Supervisor Pat S. Herrity (R-Springfield) refrain from asking the Auditor of the Board to take on new assignments until he has consulted other board members.

“The Auditor to the Board works for the full Board and, as has been discussed on numerous occasions, his assignments are determined based on the work program recommended by the Audit Committee and adopted by the full Board,” Foust wrote to Herrity.

In an e-mail sent Friday, Foust also notified Herrity that the Internal Audit Office conducted an audit of the Community Services Bureau’s insurance-billing procedures and issued a report in March. The audit generally found acceptable controls in place, but said the lack of a sophisticated, computerized billing system had failed to keep track of as much as $1.4 million in reimbursements.

Foust, who chairs the Audit Committee, said Wednesday in an interview that it might make sense to take another look at the Community Services Board but only if other supervisors support it.

“It needs to be discussed,” Foust said Wednesday. “We can’t operate by press release, and that’s what happens when one or two board members rush to get their name in the paper before we consider all the aspects.”

Herrity said Wednesday he would continue pushing to have the Auditor of the Board take a broader look at the Community Services Board.

An $8 million budget gap has already forced the Community Services Board to cut back or delay services for some of the county’s most vulnerable people. The budget gap is projected to widen to nearly $9.5 million in the coming fiscal year, forcing the county to pump in more money. The Community Services Board, also known as the CSB, and the Human Services Council plan to conduct a series of public hearings, beginning June 4, to discuss what services the agency should focus on and what it should reduce or eliminate. An online survey has also been set up here and a full schedule is here.

The Internal Audit Office’s review, which covered July 2009 to September 2010, found that the CSB lacked an adequate computerized accounting system to accurately track all the revenue it was due from Medicaid or insurance reimbursements.

In one 12-month period, for example, the audit found a discrepancy of $1.4 million between the amount the agency was owed and the revenues it had received. The audit also found that agency failed to obtain the proper pre-authorization from insurers for some services, collect delinquent fees from clients and refund overpayments the agency received from some third-party insurances.

Herrity said that although the Internal Auditor took a look at the detailed procedures involved in insurance billing, it did not examine the question of whether the county agency should have taken on that responsibility in the first place. Herrity said Wednesday that the Auditor of the Board should examine the circumstances that led the social services agency to take on insurance company billings about three years ago.

“We picked up the insurance processing business and we failed miserably at it,” Herrity said. “I think they started down the path, and everybody was well meaning, but nobody got to the 30,000-foot level and saw where the path was leading them.”

George E. Braunstein, executive director of the CSB, said the agency assumed responsibility for billing because it was the method preferred by the state of Virginia and because it enhanced the CSB’s mission of identifying and arranging care for people who have substance-abuse problems, mental illness or intellectual disabilities. By assuming responsibility for billing, the CSB ensured that clients who needed care would be able to see the most appropriate care provider without worrying about whether that provider was out of network. Providers also agreed to render services as if they were in an insurer’s network, Braunstein said.

On Friday, Herrity urged Michael B. Longhi, who is the Auditor of the Board, to audit the CSB for the board of supervisors. Herrity’s letter suggested that difficulties in Fairfax County obtaining reimbursement could account for as much as $400,000 to $900,000 of the budget gap reported in the Infant and Toddler Connection program.

The Auditor of the Board and the Internal Audit officer are separate entities, county spokeswoman Merni Fitzgerald said.

As Auditor of the Board, Longhi operates like an inspector general and runs the Office of Financial & Program Audit, which answers to the Board of Supervisors.

The Internal Audit office is a separate agency that reports to County Executive Edward L. Long, Jr. and performs periodic reviews in compliance with federal auditing standards, Fitzgerald said. The Internal Audit office investigates allegations of fraud or ethics violations, Fitzgerald said.