How many calories can a person weighing 170 pounds burn running at a slow pace?

Using the American College of Sports Medicine's metabolic equations, running at 5mph would result in a 170lb person burning ~12 calories/min. 4mph would be about 10cals/min. So if you're following the current physical activity guidelines, you'd burn about 300-360 calories in one 30 minute session at 4 or 5mph (which would be a slow pace)