good and bad in reclamation

Is there any good and bad effects to the environment in reclamation in HK?
Spelling is"reclamation" with no "i".
An example of the HK International Airport runway must be given;better than the Victoria Harbour's examples..
The good points in building the 3rd airport runway are:-
(1)There is land reclamation which means recycle earth,soil,sand from nearby mountains to reclaim land for buildings+runway.
(2)A piece of land is reclaimed by land,turns back into land etc. therefore more land gained by HK
(3)The site for the airport will be reclaimed from the sea to make land from the second nearby runway.hence promote more jobs for workmen.and family.
(4)To get back business after it has been lost to Canton Airport New Runway recently built.
The bad points to the environment are:-
(1)Kill a school of devil chinese white dolphines only.
(2)Damage and destroy the marine ecosystem only.
Hence we are not damaging the marine environment,but protecting the environment from the impact of climate change.