Starting a specialist Tour operator

Hi, this is a bit more complicated than a normal tour operator, so any help would be much appreciated.
I am looking to start a tour company taking foreign metal detectorists to go metal detecting on the beaches of the east coast of Spain (Valencia to Barcelona stretch). The detecting is slightly specialist in that it involves the detectorist going into the sea and detecting up to neck high in water. We don't metal detect on the dry sand, it is wet only. I know that due to the illegal pillaging of ancient history, Spain is quite tough on metal detecting, but as this is a tour, bringing in tourism revenues and is not in any area where ancient finds could be made, and also as it appears people already go metal detecting in the area, I wanted to check on whether we would be breaking the law and have our equipment confiscated or if we would need a tour operator licence or metal detector licence. I have emailed the town hall of Salou in Spanish but have not received any response. I hope you could help me.
Already Tried:
I have emailed the town hall in Salou I have searched spanish metal detecting websites and chat rooms I know that in the past (2002) there were groups who went to salou to metal detect, but I haven't heard of any going recently.

Hello Tinobrewer,

The general use of metal detectors is not prohibited, unless it is used in a protected area for archeological and historical reasons, when the use of such items will be considered illegal.

In order to set up a tour operator business , you will need to have the required licenses and you may even be required to have a permission to use the metal detectors ( You can find this out by enquiring directly at the town hall or phoning them ) . I am unsure about the legalities of using the metal detector use as a touristic lure to attract clients into your business, so again I am afraid that you will need to make the relevant enquiries at the town hall.

If you find that the language barrier is a problem I advice you to contact a gestoria in Valencia or Barcelona that can make the relevant enquiries in your behalf as well as file the corresponding application forms.

Best Regards,