Do I need isolation for op-amp stages in a current pump circuit like this?
Your circuit, as shown, will not work. U1 appears to be connected as a malformed Howland current pump. As shown, the output will swing from rail to rail. A Howland pump configuration looks like







simulate this circuit &ndash; Schematic created using CircuitLab

and it should be clear that, for 30 volt supplies and the resistors you've shown, especially R4, there is no way you'll get more than about 3 mA out.

So show us what you really have.