Caesium-137 has a very low rate of neutron capture and cannot be feasibly disposed of in this way, but must be allowed to decay.
sˈiːsiəm wˈʌnhˈʌndɹɪd θˈɜːɾi sˈɛvən hɐz ɐ vˈɛɹi lˈoʊ ɹˈeɪt ʌv nˈuːtɹɑːn kˈæptʃɚ ænd kænˈɑːt biː fˈiːzᵻbli dɪspˈoʊzd ʌv ɪn ðɪs wˈeɪ, bˌʌt mˈʌst biː ɐlˈaʊd tə dᵻkˈeɪ.