nl400 tptk 3b pot vs fish

Pacific, $2/$4 No Limit Hold'em Cash, 5 Players
Poker Tools Powered By Holdem Manager - The Ultimate Poker Software Suite.

MP: $399.50 (99.9 bb)
Hero (CO): $407.10 (101.8 bb)
BTN: $400 (100 bb)
SB: $402 (100.5 bb)
BB: $400 (100 bb)

Preflop: Hero is CO with K A
MP raises to $8, Hero raises to $30, 3 folds, MP calls $22

Flop: ($66) J K 6 (2 players)
MP checks, Hero bets $33, MP calls $33

Turn: ($132) 8 (2 players)
MP checks, Hero bets $70, MP raises to $140, Hero folds

Results:

opponent fish, sometimes tilty
read: chminr 3rd pair single raised pot , turn continues

I am not sure how to play this hand because, chcall chminr is way too strong line. So what can I do on the turn if I am not sure whether I can call river if he bets?