A Republican senator from Iowa is questioning Google's use of Moffett Field following an NBC Bay Area investigative story last week.
Sen. Charles Grassley of Iowa said in a letter to NASA Administrator Charles Bolden that his office had received "troubling allegations" regarding Google's use of the NASA-run Moffett Field in Mountain View for private use.
To read the whole letter, click here.
NASA has a policy of allowing private companies or citizens to use Moffett Field for scientific purposes.
The contents of Grassley's letter were first reported by Dow Jones.
Google pays NASA $113,365.74 a month to house planes for the use of its executives at Moffett Field, which is just minutes away from the airfield.
In his letter, Grassley asked for details about the agreement that allows Google to use the air base and clarification of a report that Google is allowed to construct more than one-million-square-feet of office space and research and development facilities on the property.
NBC Bay Area has requested a statement from both Google and NASA about the letter.