The Defense Department gave in yesterday to pressures from the media and agreed to add a daily newspaper correspondent to its proposed "pool" of 11 journalists who would accompany U.S. military forces on future "contingency operations" similar to last October's invasion of Grenada.

At the same time, it was learned that the Pentagon has proposed ground rules that would expose the pool to an extraordinary degree of battlefield censorship. This would be akin to the censorship exercised over the press in World War II and the Korean war. No censorship was imposed on coverage of the war in Vietnam.

The decision to expand the pool was taken after protests from the American Society of Newspaper Editors, the American Newspaper Publishers Association, individual newspapers and the president of CBS News, Edward M. Joyce.

Under the Pentagon's original plan for future coverage of small wars, the 11-member pool was to consist of six television representatives, one magazine correspondent, two wire-service reporters, one radio broadcaster and one photographer. The theory was that the wire services -- the Associated Press and United Press International -- would serve the needs of their newspaper subscribers.

The revised plan would require the publishers association to designate eight newspapers eligible for inclusion in the pool. The newspapers would then set up a rotational system to determine which would have a correspondent in the pool at a given time.

The ANPA chairman and president, Richard J.V. Johnson of the Houston Chronicle, responded cautiously to the Pentagon's revised plan. He was pleased, he said, at the "decision to recognize the vital role newspapers play in covering our nation's armed forces." But he said he would not respond to the specific pool proposal until he could "consult with U.S. newspapers and with other newspaper organizations . . . . "

The question of who should be included in any pool is one issue facing news organizations. Other issues, however, are raised by the "ground rules" the Pentagon proposes to impose on battlefield coverage.

As currently drafted, they confer on the military commander broad censorship powers. Correspondents accredited to the battlefield are prohibited from transmitting any military information "unless officially released by U.S. or Friendly Forces commanders or their representatives."

The "senior on-scene U.S. military commander" is designated as "the sole releasing authority for all military information material contained in any medium" within his area of operation.

A number of specific prohibitions are listed under the heading "Information not releasable under any circumstances."

These prohibitions include references to future military plans or operations; information on any "vulnerabilities, weaknesses or shortfalls" in American units; information on "in-progress operations against hostile targets," and information on the effectiveness or ineffectiveness of enemy tactics or operations.

American casualties are to be described only as "light," "moderate" or "heavy" as "applied to the size of the force" engaged. There will be no "body counts" of the enemy: " . . . There is no way of determining an exact number of enemy killed. Duplication and other errors in counting may raise estimates, and there is no way to account for the number removed from the battlefield, buried by enemy forces or those who later die of wounds. The popular term 'body count' implies a precision that never has, and never can, exist."

The penalty for violation of the proposed ground rules could be loss of accreditation by the correspondent and his news organization.

The proposed ground rules represent an effort by the military to control battlefield reporting. No such rules were imposed during the Vietnam war, although previous wars were covered under a formal system of censorship.

The accreditation system being proposed by the Pentagon, like the censorship rules, would apply not just to the original pool but to any journalists subsequently allowed in the battle zone. The system would weed out the aspiring free-lance journalists -- and thrill seekers -- who appeared in great numbers in Vietnam.

No one would be eligible for accreditation who did not earn "at least 50 percent of their income from journalism and who did not have a firm commitment for the purchase of their product."

"While accreditation does not provide the news media any special privileges," the proposed directive states, "it does facilitate their access to releasable information. It does not, however, guarantee access. This, along with use of facilities, remains the commander's prerogative."

The directive also suggests that the mere creation of a "national press pool" does not ensure that it will be allowed to accompany U.S. forces into action. Two conditions must be met. First, the "host country," in which the action takes place, must approve " 'in principle' the presence of news media accompanying U.S. forces . . . but no approval of specified news media representatives is intended." However, a related document says "all news media representatives participating in a contingency press pool must be acceptable to the host nation involved."

Secondly, use of the pool must be approved by the secretary of defense, the chairman of the Joint Chiefs of Staff and the commander of the operation, each of whom presumably has a veto power.

All pool members would be required to sign "documentation agreeing to the ground rules for conduct of the press pool and indemnifying the U.S. government in cases of injury or death."

The authority of the field commander over the correspondents is spelled out in this way: "The on-scene commander is the ultimate authority during the operation and is empowered to take those actions he deems necessary to ensure mission accomplishment. This includes removal of any news media representative from the area of operations if the commander determinessuch action must be taken . . .