Gas leak calls explode in Los Alamos
New Mexico Gas Company has shut down the main gas pipeline that supplies Los Alamos and many of the communities between Albuquerque to Taos for maintenance and inspection, which under federal law is mandated to take place every twenty years. This shutdown, however, has unfortunately resulted in an explosion in the number of “gas leak” calls to the county’s utilities department.
In order to supply customers during the outage, contractors for NMGC have routed natural gas to the county via a “virtual pipeline”, where liquified natural gas (LNG) is delivered by truck to a temporary pumping station at NM 502 and Camino Entrada. The LNG is then vaporized back into a gaseous state and pumped into the county’s gas distribution network.
Natural gas consists primarily of odorless methane, and since a major gas explosion in 1937, federal law has required that an odorant — typically a noxious sulfur-based compound in the “thiol” or “mercaptan” family — be added to alert customers to the presence of natural gas well below the level required to sustain an explosion. (Thiols are also the active ingredient behind natural odors such as skunk spray, rotting food, and morning breath, and the human olfactory system has evolved to detect them at vanishingly low concentrations.)
Local gas customers were not supposed to notice any changes in service; however, the virtual pipeline has had some very real hiccups.
On June 29 around 11 am, the entire Pajarito Cliffs Site at Camino Entrada, along with several surrounding businesses and LANL offices, were evacuated because of the “strong smell of gas” throughout the complex.
The Los Alamos Fire Department and the Los Alamos County Department of Public Utilities eventually determined that there was no actual gas hazard, and that the smell permeating the neighborhood was due to the unexpected atmospheric release of concentrated odorant from the pumping station across the street.
County first responders have also been dealing with a dramatic rise in the number of customers reporting a “smell of gas” at local residences and businesses.
It’s not uncommon for gas distribution systems to have tiny leaks below the limit of human detection. These can result from loose appliance connections, faulty meters, pressure relief valves, or even corroded underground pipes. But humans’ extreme aversion to thiol compounds means that a tiny fluctuation in the on-site odorant mixing process can result in an undetectable leak smelling larger than it actually is.
The county expects that the NMGC pipeline shutdown will last through the summer. Until then, customers will likely be at the mercy of fluctuations in the “virtual pipeline” process, at least until all the leaks have been sniffed out.
If you smell gas:
If it’s a faint and occasional whiff of gas, call the Los Alamos County Utilities customer service line at 505-662-8333, during normal business hours to arrange for county utilities to perform an on-site survey.
However, if the smell of gas is strong and unwavering, and/or there are other indications like the hiss of escaping gas or dead vegetation around a gas meter or underground pipe, then immediately evacuate the area and call 911.
More information about natural gas in Los Alamos can be found on the county’s website.