Should I be concerned that the Powerhouse used to be a powerplant? I am interested in buying here but I'm not sure if there may be potential health threats due to the building's previous function.

I wouldn't be that concerned. however i would be concerned about the city's plan to erect middle income housing across the street. your potential new 'hood is going to be one huge construction zone for several years and your views will be obliterated.

make sure you know about hunters point south development

all the LIC area is known to be not safe in term of ground pollution and therefore all buildings do a clean up prior of building, like what they are doing on the tennis court area, checking the safety of the ground pollution then they will start building up.

You can request proof to the office and have it on your contract that it is safe but most likely it is as the city probably checked for all that before declaring them condos (or rento-condos i should say:)

I would agree with the others be aware that construction will take place and buildings will be obstrcuting your view so dont buy for the view.