The National Endowment for the Arts yesterday unveiled a new Hispanic art exhibit to celebrate the start of National Hispanic Heritage Week and to promote the NEA within the Hispanic community.

"We're trying to better our understanding of Hispanic art and give more visibility to Hispanic artists," said NEA Chairman Livingston Biddle after a brief ceremony at the Endowment offices, where the show is located.

Joining in the celebration were the Equal Employment Opportunity Commission, the Office of Revenue Sharing and the Bureau of Mines -- each of which is planning Hispanic activities this week.

Biddle told the assembled group -- including EEOC chair Eleanor Holmes Norton, Mexican Ambassador Hugo Margain and the cultural ministers from Spain and Argentina -- that the Endowment had started a Hispanic task force in 1977 to "help emphasize Hispanic talent."

The task force met with initial criticism from some Hispanics, and "there is still some tension between the constituent parts of the Hispanic community and the Endowment," Biddle said. "Some feel the task force doesn't represent all elements of the Hispanic community. We will be meeting in the next couple of weeks so they can express their feelings."

A year ago, in a tense meeting, the task force told the National Council on the Arts -- the advisory body to the NEA -- that it wanted a permanent Hispanic task force. "The Endowment does not want to set up a permanent council on Hispanics," said Biddle. "If we did, we wouuld have to set up permanent councils for all the minority groups, and that would fragment the Endowment's approach."

Among other projects, the task force establishes networks for information between the NEA and Hispanic artists and art groups, encourages more grant applications from Hispanics and gives groups a better idea of what's required when applying.

"It takes years between getting word out in the field and [the groups] getting grants," said Joe Rodriguez, special assistant to the Office of Minoriity Concerns at NEA. Grants funding Hispanic art have risen from fewer than 75 in 1965 to 159 in 1979, he said.

"We're making advances," said Rodriguez. "But in terms of the many groups out there, support is minimal. Many groups are just now beginning to asseble, organize, develop. We're just at the beginning."