http://dc.streetsblog.org/2009/11/16/feds-propose-to-expand-opportunities-for-biking-and-walking-to-transit/

When it comes to infrastructure improvements that encourage more people to walk or bicycle to transit stations, how long will commuters be willing to travel? The Federal Transit Administration (FTA) has officially answered that question, proposing a significant expansion of the rules governing how close bike-ped projects should be to transit in order to receive government funding.  The FTA's new rules, released for public comment on Friday, replace the previous definition of the so-called "structural envelope" surrounding a transit station.