1996 Toyota Corolla HC failed in smog test

My 96 corolla failed for 15 mph test; HC max is 64 and measure is 69. Other readings are fine.

15 mph
HC (MAX-64, AVE-9, MEAS-69)
CO (MAX-0.55, AVE-0.02, MEAS-0.17)
NO (MAX-477, AVE-57, MEAS-190)

25 mph
HC (MAX-47, AVE-7, MEAS-39)
CO (MAX-0.54, AVE-0.03, MEAS-0.11)
NO (MAX-764, AVE-50, MEAS-130)

With 150K, the car is running as good as day 1. What could cause the high HC measure?

Any input will be appreciated