what does it mean by this sentence
Here is the sentence:
"A lot of people are smart and skeptical, but not everyone wants to devote his or her life to uncovering graft at the public buildings authority."
I don't really get the meaning of "AT the public buildings authority".
Does it mean they don't want to uncover some people's graft to the public buildings authority, or they don't want to uncover the public buildings authority's graft?

Question

what does it mean by this sentence
Here is the sentence:
"A lot of people are smart and skeptical, but not everyone wants to devote his or her life to uncovering graft at the public buildings authority."
I don't really get the meaning of "AT the public buildings authority".
Does it mean they don't want to uncover some people's graft to the public buildings authority, or they don't want to uncover the public buildings authority's graft?

Answer

the public buildings authority is a government department - either a town planning office or in charge of funding and building government offices and buildings like libraries and museums. 
Graft is corrupt payments made by developers to someone in the authority to get special treatment. Obviously there is someone employed to find out if graft and corruption is occurring and catch the offenders. He is saying not many people would want to take on that job.