The National Memorial Arboretum at Alrewas, near Lichfield, Staffordshire, England is a national (as in UK wide) site of remembrance for members of all armed forces. It gives its purpose as – “The National Memorial Arboretum honours the fallen, recognises sacrifice and fosters pride in our country. It is a spiritually uplifting place and is emerging as a world-renowned centre for remembrance.”
However they do not allow the interring or scattering of cremation ashes at the Arboretum. In a response to the question of whether it is permissible they said: “I am afraid that as a result of a decision by our Trustees in 2006, we also do not allow this practice, as it was deemed we are not a cemetery or crematorium.”
I understand and respect their stance as to why they would choose not to allow the practice, it is perhaps subtle divide they are drawing but allowing people to scatter or bury there would give the site a slightly different meaning and purpose.