Hey CTPPers, I received this query, I welcome your thoughts.

We are currently looking at environmental justice factors on Urban Arterials in the Denver Metro area, and I was wondering if you might have any insights into mapping low income population by census tract. The only data I have been able to find includes low and moderate income (from HUD), and I am having trouble even finding that data at the tract level. Do you know of a good data source for this? Any help or insights would be greatly appreciated.