Temporarily Close Email
Step 1: Tap Settings on the home screen, and then tap the Mail, Contacts, Calendars option. Tap the desired email account to close temporarily.
Step 2: Slide the Mail menu to Off, which disables your email account so that it no longer displays in the Mail app or syncs information.
Step 3: Tap the Done button to save the settings.
Permanently Close Email
Step 1: Tap Settings > Mail, Contacts, Calendars and then tap your email account.
Step 2: Tap the Delete Account button to permanently remove email as well as other features, such as contacts and reminders, that are associated with the account.
Step 3: Tap the Delete button to confirm your request.
Information in this article applies to iPad 4 with iOS 6. It may vary slightly or significantly with other products or versions.