The District of Columbia is planning to hire 20 temporary revenue officers in an effort to track down thousands of individuals and businesses that owe the city more than $23 million in overdue and delinquent taxes, a city official revealed yesterday.

The enforcement drive could yield $6 million in additional revenue during the rest of this fiscal year, D.C. Finance Director Carolyn L. Smith told the City Council during a public hearing. She said the city also plans to use private bill collection firms to locate the most elusive tax scofflaws.

According to Smith, as of last Sept. 30 there were 26,340 delinquent accounts that owed $16 million, a figure that has since reached $23 million. Of these, she said, some 7,800 owed individual income taxes while about 6,700 were businesses that owed sales taxes collected from customers.

The remaining delinquents included businesses that owed taxes on equipment or income taxes and employers who owed income taxes withheld from employes' paychecks, she said.

Smith testified at a hearing held by the council's Finance and Revenue Committee on part of Mayor Marion Barry's request for a $62 million supplemental appropriation from Congress.

Smith's Finance and Revenue Department is seeking an additional $497,000, including $350,000 for its stepped-up program to collect back taxes.

Barry recently ordered $26 million in citywide program cutbacks that include the elimination of 1,223 jobs in an effort to help eliminate a threatened $172.4 million municipal deficit. In so doing, he authorized Smith to hire five more revenue collectors to go after tax evaders. She said yesterday that she has been granted further permission to hire a total of 20 temporary employes for that purpose.

After they are trained in bill-collecting techniques, Smith said, her tax enforcement office hours will be extended to 9:30 p.m. from the present closing time of 4:45 p.m.

During the added hours, the revenue officers will telephone taxpayers who cannot be located during the daytime to push for payments. Other revenue officers now assigned to desk jobs in the tax office will pay personal visits to businesses that have lagged in payments.

By using these techniques, Smith said, she expects to collect at least $6 million in revenue during the rest of this fiscal year that otherwise would not flow into the city treasury.

Responding to a question by council member Betty Ann Kane (D-At Large), Smith said her department will compare this year's D.C. personal income tax returns with tapes of U.S. income tax returns from District taxpayers in 1977 and 1978 to learn the identities of those who failed to file city returns.

Kane suggested that Smith also check lists of automobile owners who obtained residential neighborhood parking permits to uncover possible evaders. On Capitol Hill, where Kane lives, the council member said numerous car owners who formerly kept their vehicles licensed in other states have shifted to local licensing in order to obtain parking permits. She speculated that many may still claim residency in other states for tax purposes, illegally evading D.C. income taxes.

Hearings by various council committees on the supplemental appropriations will continue through next week, after which the council will decide whether to approve it.