For detailed info how to deactivate (!) your account, follow these steps: http://www.taringa.net/comunidades/taringarespuestas/4982598/Como-eliminar-mi-cuenta-de-Taringa_.html (in Spanish).
However, in the PP you can read that actually all your data will be deleted (=no deactivation) upon closure of your account: http://www.taringa.net/privacidad-de-datos/#cierre-de-una-cuenta
Conclusion: perhaps someone can clarify what will actually happen when deleting an account. We tried ourselves and after deactivation we could simply log in again. So for the real deal, try anonymising and/or sending them a request (firstname.lastname@example.org) to truly delete your data.