Neighbors of a natural-gas pipeline south of Dolores are upset about noise levels coming from a pumping station.
The Mid American Pipeline transports natural gas through Montezuma County along an energy corridor from U.S. 160 to Colorado 184 to U.S. 491 and beyond. It is operated by Williams Northwest Pipeline, and includes the Dolores pump station on the corner of Road P.2 and Road 33.
In 2013, owner Mid-American Pipeline obtained a high-impact permit from the county as part of a redesign of the pumping station. Last fall, it replaced two gas-fired engines with electric motors as a way to reduce noise and emissions, and to improve efficiency.
But neighbors say the higher frequency of the electric pumps is louder and more annoying than the old pumps.
"When it's on, it is really quite loud, and they said it would be quieter," said neighbor Jan Wright.
After a group of neighbors reported their concerns to the county, the commissioners ordered an independent sound test. A preliminary report released in July by JK Inc. indicated that at three fenceline locations, noise levels from the control station exceeded county nuisance standards in the evening.
But whether those standards apply is a point of disagreement.
Under the county land-use code, volume levels must be less than 70 decibels at the property boundary. In a residential area, county regulations state that noise levels are not to exceed 55 decibels any point on the property boundary between 7 p.m. and 6:59 a.m.
Volume levels from the JK Inc. test on May 7 recorded 58 decibels, 61 decibels, and 67 decibels at 7 p.m., above the 55 decibels threshold allowed for that time.
According to planning documents, the pump station "does exceed this standard at certain places along the fenceline."
"The results are preliminary, and we are still waiting for the final conclusions," said county planning director LeeAnn Milligan.
But in an e-mail, Mid-America Pipeline asserts they are in compliance with noise requirements of its operating permit based on their own noise survey. The company believes they are exempt from the current county noise standards because the pump station was operating before those rules were implemented.
Despite the conflicting reports, Rick Rainey, vice president of public relations for MAPCO, says the company is working to reduce the noise level at the plant.
"MAPL is in the process of insulating piping and equipment, as well as installing insulated covers over the pumps to further reduce noise," Rainey wrote in an email. He said the plan is to install the mitigation system this winter.
Neighbors are eager for a solution.
"I can hear the high-pitched squeal inside my house with all my windows closed," said Jeff Kennedy, a close neighbor of the station. "It has changed my quality of life. There are fabricated modular enclosures that could be built around the pumps to silence them, and they can be removed for maintenance."