ʻO ka mīkini pahu pōhaku ʻekolu-lima piha i hana ʻia e kā mākou hui he mau mea maikaʻi o ka hōʻemi ʻana i ka ikaika o ka hana o nā limahana, ka hoʻomaikaʻi ʻana i ke ʻano hana, hoʻomaikaʻi ʻana i ke kūkulu ʻana, a hoʻemi i ka hilinaʻi akamai o nā mea hana.He holomua ia ma ke kahua o ka hana ʻenehana tunnel.He kūpono ia no ka ʻeli ʻana a me ke kūkulu ʻana i nā tunnels a me nā tunnels ma nā alaloa, nā kaʻaahi, ka mālama wai a me nā kahua kūkulu hydropower.Hiki iā ia ke hoʻopau maʻalahi i ka hoʻonohonoho ʻana, ka wili ʻana, ka pane ʻana, a me nā hana hoʻoponopono o nā lua puhi, nā lua bolt, a me nā lua grouting.Hiki ke hoʻohana ʻia no ka hoʻouka ʻana a me ka hoʻokomo ʻana i nā hana kiʻekiʻe e like me ka bolting, grouting, a me ka hoʻokomo ʻana i nā auwai ea.