Concerns are increasing that asbestos from the derelict Grade II-listed Colwyn Bay pier could contaminate the beach.
Asbestos sheeting was used in the construction of the main pavilion in the 1930s.
A report by Conwy council said the sheeting could break up if the pier was hit by bad weather and wants to dismantle it as soon as possible.
But it needs Welsh Government approval before work can start.
The pier, which has been closed since 2008, started to collapse in February.
A storm caused further damage and sections of it had to be demolished as an emergency measure.
Plans to dismantle it were approved by the council - which owns the pier - in July but the final decision rests with the Welsh Government.
The council also needs a marine licence from environment body Natural Resources Wales (NRW) and is concerned it may not get permission until after the bad winter weather has begun.
An internal council report, released to BBC Wales under the Freedom of Information Act, said: "The strong impression remains of a rapidly deteriorating structure.
"The external walls of the pavilion were in a very poor condition when the deck was accessed some three to four years ago. It is surprising that they have not yet failed under wind load.
"If the walls fail, then a dominant opening would form, significantly increasing the wind pressure within the pavilion, leading to a high risk of the asbestos cement sheets being lost from the structure."
The asbestos sheeting was identified in a 2012 survey of the pier.
When materials containing asbestos are disturbed, fibres are released which, if inhaled, can cause serious diseases.
The report also said the council had been considering how to clean the beach if the pavilion was to collapse.
The Welsh Government confirmed it was considering an application to dismantle the pier.
NRW said it had received a marine licence application in relation to Colwyn Bay pier, which was currently out to consultation.
"We would consider any request to fast track a permit on a case by case basis," a spokesman added.