Code:
ps --suitable=options | awk '$7 ~ /^[f]60/ && $5 > 8 { print $1 }' | xargs kill
The "suitable options" and the field numbers to use in the awk script depend on which platform you are on. Consider this pseudo-code.
Are you sure you understand the consequences of "kill -9"? You should use a less drastic signal if at all possible.
