Run up to 4 x 2km laps, increasing the pace on each lap.
The 'lap' is an out-and-back course from the Pillars (bins, to be precise) to Government House Drive.

Use the 'bottom of the tan', starting clockwise from the Pillars. Run two reps out then two reps back and regroup at the Pillars before the next set of four. Although the reps are quite short so is the recovery, making this is a tough session.

This session starts at the 400m start (near the goal posts closest to the river) and finishes 7m before the next 100m line (measure before you start the session). After each rep, walk back to the start. 
Options: reduce or increase number of reps, e.g. 6 x 600m. For a quicker tempo run 2 x 3 x 600m skipping a rep or two in the middle of the session.

Run from the Pillars to the 750m mark, then 500m back towards the Pillars and then 250m to return. The tempo of each set picks up as the distance of the rep decreases. Complete three sets in total. Recovery: start on 4.30, 7.45 and 11.00.  
[Alternate session: skip the last set or scale it back e.g. finish with 2 x 500m or 2 x 250m.]

Recoveries are 4 mins after the 2km then do the 750s 'on 4.15'.
For the 2km: Start at the bins and head up the tan towards Government House.  Turn around at Govt House Drive and head back to the Pillars. 
The 750m reps are run out and back along the bottom of tan.