Run the repeats at half-marathon pace, or somewhat faster.
Many runners find running mile repeats on a track boring.
If that is you, use a measured mile on a road course for this workout instead of going to the track. Three miles remains a good rest-day workout. Another option would be to practice your warm-up for the race. If you want to run fast in any workout or race, you should warm-up. A good workout today might be to jog 1-2 miles, then sit down and do some stretching.