Denton’s official gas drilling task force made scant progress this week with new recommendations to reduce noise created by natural gas drilling and production facilities.
A 3-2 vote defeated a measure to limit the amount of noise such facilities could make at night and in neighborhoods.
Another 3-2 vote encouraged the city to evaluate whether low-frequency noise should be included in the city’s present noise limits. But shortly after that vote, task force member John Siegmund backpedaled, saying he was only in favor of evaluating the idea, not putting forth any additional regulation that would bring a cost to doing business.
“The problem about sound — it’s all subjective,” Siegmund said. “There’s not a scientific answer.”
The noise items were brought forth by Vicki Oppenheim, an environmental planner, but fellow task force member Tom La Point, an environmental researcher at the University of North Texas, did the talking.
Because operators are looking to drill and install gas production facilities in all areas of the city no matter the zoning, reducing noise makes sense, La Point said.
“The idea has a lot of value because of zoning — it’s a value to have lower noise,” La Point said, calling the city’s ability to scientifically measure sound a “bright light” for such regulations.
Denton planning director Mark Cunningham and Darren Groth, head of the city’s new gas inspection program, described some of the current enforcement problems, or those they could have, with noise regulations, depending on how they are drafted.
At first, Ken Banks, director of environmental services, said the city’s current noise limits were well vetted. But later, when questioned by the task force about noise exceptions granted to other businesses, Cunningham told the group that the current noise limit — 75 decibels at 300 feet from a production site — was selected through compromises.
The intensity of sound waves are measured in decibels, or db.
Later, the city staff calculated that 75 db at 300 feet diminishes to a little less than 65 db at 1,000 feet — the city’s new setback distance between a gas well site and a home or other protected use.
“That was by mere luck that it worked out,” Cunningham said.
No other entity — with the exception of a music festival under certain circumstances — is allowed to exceed the 65 db limit beyond a property line, city staff said.
Instead, the city staff told the task force that it might be better to require operators to conduct an ambient noise study for a neighborhood as part of a permit application, the way many other cities require, and hold operators to certain levels at or slightly above ambient.
But the task force declined to make the recommendation.
The split votes highlight a division between the citizen and industry-related members of the task force.
Siegmund, a retired petroleum engineer, voted with Ed Ireland, executive director of the industry-funded Barnett Shale Energy Education Council, and Don Butler, a project manager with New Tech Global, an oil and gas consulting and engineering firm.
In evaluating low-frequency noise, similar to the way Fort Worth now considers such noise not only from drilling pad sites but also from compressor engines, Groth said the city may have to consider the kind of device used to measure sound, since equipment capable of measuring sound waves outside the range of human hearing can be more expensive.
Most adults cannot hear below a frequency of 20 hertz, or above 20,000 hertz. Sounds below 20 hertz are considered low-frequency noise.
Fort Worth does not permit low-frequency noise to exceed 65 db either, Groth said.
Beyond certain levels, noise can cause hearing loss, a common and well-known health effect. People who are exposed to constant or high levels of noise can also suffer other adverse health effects. Research has found effects similar to other stress-related illnesses, such as loss of productivity, sleep disturbances, speech problems and high blood pressure, according to the Environmental Protection Agency.
Gilbert Horton, spokesman for Devon Energy, said Denton should not adopt rules that leave too much discretion to the city employees.
“They can be enforced unreasonably,” Horton said. “We’ve seen it in other municipalities.”
Denton resident Bruce Walker reminded the task force that its charge, as part of a second phase of review of the city’s ordinances, was to recommend improvements and not consider the noise and setback rules from the first phase as the final word on the matter.
“It is to protect the citizens’ health and welfare,” Walker said.
His wife, Elma Walker, told the task force that noise regulation was important to the community, pointing to her own experience when wells were drilled close to their home in Robson Ranch.
“It was a ridiculous amount of noise for a year and a half,” Elma Walker said.
The task force agreed 5-0 to recommend that the city evaluate whether its security requirements for well and production sites are sufficient. They tabled discussion over surface reclamation and maintenance items to next week.
The committee is scheduled to meet through March and advance its recommendations to the City Council, which has the final authority on the adoption of any new rules.
On Feb. 7, the City Council enacted a four-month moratorium on new drilling permits while the city revises its drilling and production ordinance.
PEGGY HEINKEL-WOLFE can be reached at 940-566-6881. Her e-mail address is pheinkel-wolfe@dentonrc.com .
