Prevent Objects Deletion from _SYS_BIC by Users only having SELECT privilege on _SYS_BIC

Hi Friends,

I know whenever we create a model in a Package and activate it, the runtime Column views are created and stored under Column Views section of _SYS_BIC schema.

By giving the SELECT Privilege on  _SYS_BIC to my USER(say Usr1), he is able see the all the Column Views created under _SYS_BIC,

for which he is able to see the definition as well as the corresponding Data Preview.

Now I have 2 requirements which are listed below:

1. Even though Usr1 has only Select Permission on _SYS_BIC but still he is able to Right Click and Delete any object from _SYS_BIC how to restrict this.
2. Also how do I prevent Usr1 from being able to Right Click and see the definition of Views using View Definition.

Thanks & Regards

Nagarjuna