Fracture stimulation technology increases well production, while reducing environmental impact, in tight-gas fields such as Wattenberg. Tight gas is found in reservoirs that do not allow gas to pass through easily. Tight-gas drilling can be compared to drilling a hole into a concrete driveway. The rock layers that hold the gas are very dense, so the gas doesn't flow easily. Frack technology is a well stimulation method in which water-based frack fluid under extremely high-pressure is pumped down a well. This fractures the reservoir rock near the well bore to create pathways for the natural gas to flow to the wellhead. Some wells are re-completed and fracked to enable production from a second geological layer. This can also prop open fractures that may have closed through time. A well may be refracked every one to two years of operation to stimulate further production.
Two websites that provide further information about fracking are the COGCC and Frac Focus websites. Frac Focus is the hydraulic fracturing chemical registry. It is a joint project of the Ground Water Protection Council and the Interstate Oil and Gas Company Commission.