Here are some general sources of information on light pollution, radio interference, and space debris:

Light Pollution

• International Dark-Sky Association
• International Astronomical Union Commision 50: Protection of Existing and Potential Observatory Sites. At the IAU General Assembly in Beijing in August, 2013, there was a special session on protecting observatory sites. Details are available here.
• Protecting the night sky in Chile (in Spanish)

Radio Interference

• General introduction to radio interference (at NRAO)
• Spectrum management (also at NRAO)

Space Debris

• NASA's Orbital Debris Program Office
• Inter-Agency Space Debris Coordination Committee
• studies of orbital debris impacts on the Hubble Space Telescope