Here is the route profile for the workout. From my front door it drops 1150feet to the turn around. I'm lucky to live in a place with this option. I can just as easily reverse this and climb to 9200ft from my door.
The loose goal was to run MAF down to the 5 mile point, then turn around and run tempo back up. I didn't look at HR once, instead I tried to hold my effort on the edge of wanting to slow down but not needing to. Ventilatory threshold is another gauge for this effort.
10 miles total in 1:09:59. Average pace 6:59 (barely). I will admit that near the end I was racing the clock and well over threshold. Average HR 162