Jeremy Hefner and Jordany Valdespin would have been due Major League minimum contracts worth $500,000.
In sum, then, the Mets saved roughly $4 million off of the 2014 payroll by non-tendering these five players. None of the moves should have been the slightest bit surprising. Justin Turner was worth 0.5 fWAR last year. No quantity of clubhouse smiles makes him a key part of a winning baseball team. Quintanilla (-0.3 fWAR) and Valdespin (-0.4 fWAR) were both replacement level players.
Atchison was a low strikeout reliever (5.56 K/9) who was similarly below replacement level (-0.1 fWAR).
Hefner had his moments, but in an ERA where offense is declining, his 4.34 ERA over 23 starts only produced a 0.3 fWAR in 2013. Baseball Reference's accounting suggests that he was below replacement level in 2012 (-0.3 WAR) and 2013 (-0.8 WAR). Given that he will miss all of the 2014 season with Tommy John surgery, he was just wasting a roster spot and half a million bucks to the 2014 Mets. Ideally, by 2015, the Mets will have less use for sub-replacement level pitchers.
My updated 2014 Mets payroll projection (Mets Payroll 12-2) now puts the Mets hard and soft commitments at $70.66 million. Again, that's by evenly distributing Jason Bay's $15 million between 2014 and 2015. If the team is really planning on exceeding last year's $87 million salary number, they now must spend $17 million to do so.