According to Wikipedia:
Mitigation fees are similar to impact and linkage fees but they differ in their focus on the environment. These fees are charged to reimburse or compensate the community for the negative impact that development may have on the community. In some cases these fees are used to help preserve a component of the local environment and regulate pollution. There is debate about whether these types of fees are a legally acceptable form of government funding like impact and linkage fees are.
Why would the City of Beaumont's financial books show $6.9 million in mitigation fees were paid to the city's general government management services consulting firm, Urban Logic of Temecula, with the Potrero Bridge Project in the memo field? The entries show these payments were made over two years, from September 2010 to October 2012.
Don't you want to know? I do.