Licensed Well Driller and Pump Installers - Colorado Division of Water Resources (DWR). If you need to find a licensed well driller, this link lists DWR licensed contractors by City, Company, Last Name and License Number.  The lists are updated quarterly.  

Well Permit Search - DWR's online tool to search for existing permits by permit number, location, owner, address and more.  

Guide to Colorado Well Permits - A 20 page brochure with a comprehensive overview on types of well permits, designated basin in formation, residential wells and wells with water rights.  DWR publication, 2012.  

Wellcare Hotline - A wealth of information for private well owners from the nonprofit Water Systems Council

The Private Well Class - Another excellent online resource for well and septic system owners.  This site offers free videos, webinars and e-mail classes and podcasts.  This is a service of the University of Illinois at Urbana-Champaign

How to Disinfect a Well - A video with step-by-step instruction to disinfect a well