Are all pool returns removable?

[hulla]

Can someone confirm that my pool return is removable? I can't undo it by hand and didn't want to use a wrench until I get some reassurance that it is ok. Picture attached...

[attachment=0:2kts0qaj]IMG_20130526_172054.jpg[/attachment:2kts0qaj]

 

[frustratedpoolmom]

It should be. How old is the pool? Hard to tell from pick but the sides are they like a giant bolt? So the wrench can grab hold?