A massive new weapon has now deployed in the battle to clean up the Kirtland Air Force Base fuel leak: forty thousand pounds of granular activated carbon that is stripping aviation fuel constituents out of the contaminated water.

At a cost of $14.2 million, the U.S. Air Force has built a system of three extraction wells, pipes and a 4,000-square-foot, full-scale treatment plant, complete with two metal vessels that each have 20,000 pounds of carbon, that has now cleaned 52 million gallons of water contaminated with ethylene dibromide.

The full-scale treatment system became operational on December 31, 2015, and is now pumping and cleaning 400 gallons of water a minute, or 576,000 gallons a day. It has the capacity to treat 800 gallons a minute. The Air Force and the New Mexico Environment Department gave area residents a glimpse of the treatment system during a field trip to Kirtland on April 23.

The system consists of three extraction wells near the northern edge of the underground plume of EDB-contaminated water in a Southeast Heights neighborhood that’s outside the base’s boundaries. The pumped water flows through underground pipes through the neighborhood, onto the base and into the treatment facility, where it is filtered and then sent to the first carbon-filled vessel.

The water enters the plant with an average EDB concentration of 100 parts per trillion, which is twice the allowable limit, said Adria Bodour, the Air Force’s lead scientist in the effort to clean up the mess that was first detected in 1999.

It takes 12 to 13 minutes for a gallon of water to make its way through the 20,000 pounds of carbon, and when it is through, it has no detectable EDB, Bodour said. From there it goes into the second carbon vessel for another cleaning, or polishing, and then to one of two places: KAFB’s 18-hole golf course, where it is used to water turf, or an old drinking water well on base where it is basically poured down the well shaft and allowed to leak back into the aquifer.

The water coming out of the first carbon vessel is tested once a month, and if that water ever tests positive for EDB, the entire system will be shut down and a new carbon vessel installed. So far, the system has removed 20 grams of EDB. There are 1,000 grams in a kilogram, which is 2.2 pounds.

A fourth extraction well is expected to be operational by the end of the year, and up to four more will be installed if needed, said Dennis McQuillan, the NMED’s lead scientist on the project.

The leak

No one knows exactly how much aviation fuel leaded into the aquifer from Kirtland’s Bulk Fuels Facility, which opened in 1953. That’s because no one knew until November 1999 that two 16-inch diameter fuel pipes buried 10 feet underground had sprung leaks. On November 16, 17 and 18 of that year, crews were unloading fuel from a tanker truck. The fuel was supposed to be vacuumed through the pipes into two above-ground storage tanks, but something else happened. The fuel started bubbling up out of the ground — it was gushing out of the holes in the pipes — and KAFB officials knew they had a big problem. Only 51 percent of the fuel made it into the tanks those days; the rest leaked out, Bodour said.

It wasn’t until 2010, when the underground pipes were dug up, that officials knew why they had leaked. Each underground segment of the two pipelines had two holes on their bottoms. Afterwards, officials surmised that the holes were caused by years of vibrations and soil compaction that resulted when tanker trucks or rail cars pulled up to the loading station. The trucks and rail cars were directly above the buried pipes. The vibrations caused rocks underneath the pipes to dig into them and eventually puncture them.

So, no one knows when the leaks actually started.

Further complications

Here’s another complication that has prevented officials from being able to estimate how much fuel leaked. It’s believed that, at first, the fuel leaked only after the unloading process had been completed. That’s because the gas was vacuumed, or sucked from the trucks and rail cars through the pipes and into the storage tanks. When a vacuum was applied to the pipes — at least at first — it caused the rocks underneath the holes to get sucked up into them and effectively plug them. After the unloading was complete and the vacuums turned off, the rocks fell out of the holes and any residual fuel left in the pipes then leaked out through the holes.

Remaining challenges

Getting the EDB out of the aquifer is the easy part for the clean-up team. EDB is a component of aviation gas and it has (and continues) to dissolve out of the actual fuel plume into the water. The fuel plume itself is 44 acres and, at one time, was easy to reach because it was floating on top of the groundwater. But, since the water table began rising in 2009 — thanks to water conservation efforts and the use by the Albuquerque Bernalillo County Water Utility Authority of its San Juan-Chama water — the gas plume no longer floats on top of the groundwater; it has smeared into a 10-foot-tall vertical zone underneath the water table. And getting it out will be difficult.

The million-dollar question is how we get that oil out of there,” McQuillan said.