What do you have near you? Do you have a congested street that could do with a study of options to try and make the traffic flow smoother? Apartment building? Rezoning? New train station? Impact of a new (blank eg. Road, station, apartment block, freeway, traffic light?) on the local community? It doesn't always have to concern the natural environment, unless you're really against talking to people, human geography can sometimes be easier- surveys, interviews are much easier to do, and you'll quickly gain knowledge about different stakeholders in your chosen issue.