1. Heat oil in a 9- to 10-qt. pot over medium-high heat. Season beef with 1 1/2 tsp. salt and 1 tsp. pepper, then brown on all sides in two batches. Set aside.
2. Add onions, leek, parsnips, celery, and remaining 3 1/2 tsp. salt and 2 tsp. pepper. Cook, stirring often, until onions soften, about 5 minutes. Return beef to pot and add split peas, lima beans, and 4 qts. water. Increase heat to high and bring to a boil. Reduce heat to a simmer and cook, uncovered, 1 hour, stirring occasionally.
3. Add barley and simmer 45 minutes. Stir in carrots and cook 20 minutes more. Season to taste with additional salt and pepper.