As far as I understand it, Disk Pools and Volume Groups are distinctly different types of storage objects within the SANtricity Array Management console. Physical drives can be grouped together into either Disk Pools or Volume Groups (or both on the same array), but can't share the same set of drives.
Looking at the "Storage & Copy Services" tab in SANtricity, there are separate drop-downs for Disk Pools and Volume Groups to show which type of objects have been configured for your array.
Here is some light reading about Disk Pools/Volume Groups:
https://library.netapp.com/ecmdocs/ECMP12404965/html/GUID-807DB3DC-DE47-4802-A87D-EA0C26DFA9B6.html
