It wasn't the one in Amposta was it as I've been badly treated there. ?  There's a problem that the BASE office sends out bills for the properties (land and house or whaterver) that they are told by the Cadastral belong to you.  The problem comes in when as part of the computerisation of their records, many errors have occurred.  I for example own a pig farm about 3Km up the road according to them.  Of course if you're not fluent in Catalan or Castellano, it can be very difficult to sort out.  Although this might be getting off topic, a lot of patience (and tenacity) is required.