James R. Cortez, his maroon Cadillac gleaming in the morning sun, arrived at the F Street Mall yesterday with a proud smile on his face and a sack of groceries at his side.

"I'm one of the fortunate ones," he said as Project Harvest volunteers unloaded the food from his car. "I've hit the number twice in two months and I feel I ought to share."

Cortez was one of hundreds of persons who responded to an appeal from radio station WHUR to donate food to Project Harvest, an organization started 11 years ago to feed the needy on Thanksgiving Day.

Contributors who included Safeway Stores, the Civil Service Employees Recreation Association, the Jack and Jill Social Club, students from Howard University and post office clerks helped Project Harvest reach its goal by noon yesterday, donating enough goods to feed more than 10,000 needy Washingtonians.

Radio station WHUR broadcast its "Morning Sound" show from the F Street Mall, between 13th and 14th streets NW, urging listeners to come down and make contributions to Project Harvest. About $6,500 was collected along with enough food to pack a 40-foot-long, 18-wheel tractor trailer furnished by Safeway. The truck already contained 30 cases of food.

"We challenged the other stores to match us," said Larry Johnson, Safeway's public relation's manager. "Hah, hah, had," he chuckled. "We started to use a smaller truck but I'm glad we chose our biggest rig. It's full.

Collected were thousands of turkeys, cans upon cans of cranberry sauce, onions stuffing mix, potatoes, and green vegetables of practically every variety.

"This is so necessary," said Lillian Green, who began Project Harvest. "The need is so great."

In 1979, in an age of welfare and food stamps, people are still going hungry in Washington, she said.

Albert P. Russo, director of the city's Department of Human Resources, watched with mixed emotions as a motorcade of delivery trucks, station wagons and sports cars rolled toward the project's food drop-off station.

"This is beautiful," Russo said. "But the dimensions of poverty in the nation's capital are profound, although it's not like Africa or Cambodia. A mother on welfare in Washington, with three children, gets $80 worth of food stamps a month."

"Hey, I know it's rough out here," said Jeff Curtis as he dropped off a check for $10. "I told my friends to come over and have Thanksgiving dinner with me. I told everybody to bring at least one thing to eat."

Ronald Jordan rolled up in a station wagon filled with goods. "Just doing what I can," said Jordan, assistant director of the Ditrict's fire safety program. "Just say this is an extension of the safety program. We want people to come alive, if only for a season."