Yep, it is! If you go to your calendar, you'll see the link to import calendar events just below your Post button. Note that it has to be in an iCal format. You'll upload a file to the calendar of your choice.
If you have a lot of events it may take awhile to upload.
I'm sorry, I should have thought of your notifications, and had you turn off permissions to the calendar until you were finished importing.
I'm thinking the damage has been done, now, but in order to stop that you'd have to go to Permissions in your control panel, choose the tab for Calendars, scroll to that calendar, and remove the permission for your members to view calendar events while you imported the calendar. Then, once the import is finished, you'd restore the permissions.
When you block a person, they can no longer invite you to a private message or post to your profile wall. Replies and comments they make will be collapsed/hidden by default. Finally, you'll never receive email notifications about content they create or likes they designate for your content.
Note: if you proceed, you will no longer be following .