How is this turn check?

[ISF]

Villan was relatively loose, and quite passive but not a complete calling station. Like 40/8/.7 stats. Do my flush outs discount the cost of this bet enough that a semibluff is profitable on this board? I think the risk of a turn CR bluff from this opponent is very unlikely, not sure about a king he was very passive and predictable.
Party Poker 5/10 Hold'em (6 max, 5 handed) converter (http://www.selachian.com/tools/bisonconverter/hhconverter.cgi)

Preflop: Hero is Button with 8/images/graemlins/diamond.gif, 9/images/graemlins/diamond.gif.
UTG calls, <font color="#666666">1 fold</font>, <font color="#CC3333">Hero raises</font>, <font color="#666666">2 folds</font>, UTG calls.

Flop: (5.40 SB) K/images/graemlins/heart.gif, 7/images/graemlins/diamond.gif, 4/images/graemlins/diamond.gif <font color="#0000FF">(2 players)</font>
UTG checks, <font color="#CC3333">Hero bets</font>, UTG calls.

Turn: (3.70 BB) 7/images/graemlins/club.gif <font color="#0000FF">(2 players)</font>
UTG checks, Hero checks.

River: (3.70 BB) 6/images/graemlins/diamond.gif <font color="#0000FF">(2 players)</font>
<font color="#CC3333">UTG bets</font>, <font color="#CC3333">Hero raises</font>, UTG calls.

Final Pot: 7.70 BB