BY STEWART M. POWELL
 Hearst Newspapers

 WASHINGTON -- With White House approval expected for limited target practice
 to resume on the Puerto Rico island of Vieques, a Navy-Marine Corps battle
 group sets sail beginning today for combat preparations on the island before
 heading to the Persian Gulf.

 Eight of 16 warships in the armada prepared to leave Norfolk, Va., and
 Charleston, S.C., today, followed by the aircraft carrier USS Dwight D.
 Eisenhower on Thursday and the remainder of the fleet on Friday to begin final
 combat rehearsals.

 The Navy is being forced to break up the components of the training to make up
 for the loss of live-fire rehearsals at Vieques. Instead, the Marines plan to stage
 an amphibious landing at Camp Lejeune, N.C., while carrier-based airplanes will
 practice bombing at two military ranges in Florida.

 Surface warships will fire their five-inch guns using nonexplosive rounds at the
 target range in Vieques under an agreement in the final stages of negotiation by
 the Clinton administration and Puerto Rico officials.

 Navy Rear Adm. Craig Quigley told a briefing at the Pentagon on Tuesday that the
 armada will conduct 18 days of ``complex war-fighting scenarios,'' including
 air-to-air combat, undersea warfare, coordinated targeting, planning for Tomahawk
 cruise missile launches and the Marine amphibious landing.

 The force includes about 15,000 sailors, aviators and Marines aboard the aircraft
 carrier, two missile-firing cruisers, four destroyers, two fast frigates, two attack
 submarines, three Marine amphibious attack ships, an ammunition supply ship
 and an fleet oiler.

 READINESS QUESTIONED

 Amid questions on Capitol Hill over the adequacy of pre-deployment training with
 the Vieques range closed, Quigley insisted: ``We will deploy the carrier battle
 group and the amphibious ready group with the training they need.''

 But privately, Navy officials said that the seven-month stalemate with Puerto Rico
 over resuming use of the embattled Vieques target range prohibits any chance of
 rehearsing the round-the-clock, integrated land, sea and air attacks that
 traditionally test the readiness of a departing aircraft carrier battle group for
 potential combat in the Mediterranean or Persian Gulf.

 Navy Vice Adm. William Fallon, the Atlantic fleet commander, and Marine Lt.
 Gen. Peter Pace, commander of Atlantic-based Marines, have told Congress and
 a Pentagon review panel that realistic live-fire combat training on Vieques is
 needed to help GIs get over their initial jitters in order to save lives in the early
 stages of combat.

 The range has been closed since April 19 when a Marine pilot mistakenly bombed
 a range observation post, killing Navy contract security guard David Sanes
 Rodriguez, 35, and injuring four civilian range workers.

 President Clinton and Puerto Rico Gov. Pedro Rossello are near agreement on
 temporary, limited resumption of Navy-Marine Corps training on an 899-acre live
 fire impact area and adjacent 11,000-acre maneuver and buffer zone, senior
 Clinton administration officials reported on Monday.

 ``All parties are working very hard to find a solution as quickly as they can,''
 Quigley said, adding that some naval forces ``may utilize portions of the Puerto
 Rican operating area, depending upon the outcome of current discussions.''

 SAND-FILLED BOMBS

 Typically, a warship armed with a 5-inch gun and a magazine of up to 500 rounds
 needs to fire about 100 rounds to qualify for the naval gunfire support mission,
 such as supporting Marines landing ashore or staging attacks against land or sea
 targets. The 5-inch gun can fire up to 20 rounds a minute over a range of up to 15
 miles.

 Nonexplosive inert rounds, known in Navy parlance as ``blind, loaded and
 plugged,'' are filled with either sand or concrete to simulate the weight of
 high-explosive fragmentation shells and fired with the same 50-pound charge of
 powder used to fire explosive shells. The concussion from the cannon firing can
 be heard for miles.

 Over the 16-year period ending in 1998, an average of 77 warships fired on
 Vieques an average of 91 days each year. Ships fired an annual average of 6,114
 rounds from 5-inch guns during that period.