Tank Issues

Hi All. Am after a bit of advice about my Sprint Tank. Its been laid up for a while. Dug her out over xmas and have noticed some bubbling on various parts of the tank (see images).
Just wondering what could be causing them. What remedies are required. is it a new tank jobby.

mnay thansk kris

 

Yeah, plastic tank. Can i get the tank rbubbed down and repainted or is it a new tank. Is there any urgency or can it wait. Sorry for all teh questions but never experienced this before.

 

Thanks for the advice. I will live with if for now and look at getting it sorted soon.
Many thanks kris

 

Following with interest. what causes the blisters in the first place? is just the fuel vaping off through the plastic??