Depending on the tech used in the 787 you could end up driving on them.
From
https://www.nationalgrid.com/stories...es-be-recycledAre the blades disposed of or reused?
Fibreglass is not totally recyclable. It’s non-biodegradable and made up of a composite of very fine strands of plastic and glass, which is extremely difficult to process at the point of recycling. Instead, it’s usually discarded as waste at landfills or incinerated.
However, while most first-generation commercial blades are being treated as waste, not all of them are destined for landfill. There are several innovative ways their raw materials are recycled to be used in other building materials or repurposed entirely in new structures.
Engineers and scientists have found a way to turn fibreglass into a key component used in the production of cement – an important material used in everyday construction. They are also finding ways to repurpose turbine blades as structural elements in their entirety – these include bike sheds in Denmark, noise barriers for highways in the US, ‘glamping pods’ across festival sites in Europe, or as parts of civil engineering projects, such as pedestrian footbridges, in Ireland.3