Less than 24 hours after the bullet-riddled bodies of three Purolator Security Inc. guards were found sprawled near their armored truck, police arrested two unemployed couples today and recovered all of the $1.8 million in cash and valuables that was stolen.

"We were Fortunate. We were lucky," Police Lt. Tony Solamita said of the arrests in the 4 a.m. Monday robbery. But, glancing at bags of recovered cash, he added, "I'd rather give this up and have them [the guards] back."

Charged with first-degree robbery and three counts of capital murder each were Donald Courture, 26; his wife, Donna, 23; ex-convict Lawrence Pelletier Jr., 36, and the woman he lived with, Evelyn Vega, 26, also known as Evelyn Pelletier, police said.

Capital murder in Connecticut may be punished by death.

Pelletier and Vega also were charged with possession of marijuana and sawed-off shotguns. The four defendents, dressed in blue jeans, were brought into Superior Court one by one at their arraignment today and asked for and received public defenders. They stood motionless as the charges against them were read.

Bond was set for each at $750,000, plus $5,000 each for Pelletier and Vega for their additional charges. A court appearance was scheduled April 25.

Those arrested had no connection with Purolator, police and Purolator officials said.

The money and valuables were found in the cellar of the Coutures' home at Wallingford after Pelletier and Vega were arrested at their Waterbury home, police said.

In what Waterbury Police Superintendent Fred Sullivan called a "senseless slaughter," more than a dozen shots were sprayed into the Purolator here shortly after an armored car pulled in and began unloading Monday morning. The bodies were found at 7:15 a.m. by an employe arriving for work.

"These poor guards - they never had a chance," Sullivan said of the men, identified as William West, 52, of Cromwell; Leslie Clark, 36, of Plymouth, and Hartford policeman Edward Cody, 46, who was wokring part-time for Purolator.

Stolen cash, jewelry, food stamps and checks were found along with two M1 semiautomatic rifles and two handguns under a tarp in the Coutures' cellar, police said.

The money, including dozens of white canvas bags of coins and several green plastic garbage bags containing waks of bills, was wheeled into police headquarters in grocery carts.

Couture was found hiding under a bed in his house at 5 a.m. after his wife surrendered to a policemen who knocked on the door after about a dozen officers surrounded the house.

At 1:15a.m. in Waterbury, Pelletier and Vega left their home with their hands raised after police called to them with a bullhorn.

Pelletier's record includes assault, burglary and narcotics convictions, according to police Detective Lt. Valentine Bochicchio, who said Pelletier also faces an armed robbery charge in connection with a theft from a drug store in Cheshire last year. CAPTION: Picture 1, Evelyn Vega, Left, and Donna Couture arrive in Waterbury, Conn., court at left in connection with the $1.8 million robbery of Purolator Security Inc. At right, officials count the loot, all of which was recovered. UPI