PCE concentration levels at the North Railroad Avenue Plume in Espanola.

BY MAIRE O’NEILL
maire@losalamosreporter.com

Updates on two groundwater plumes of chlorinated solvent contamination in Española were recently presented by New Mexico Environment Department Deputy Cabinet Sec. Rebecca Roose to the Legislature’s Radioactive & Hazardous Materials Committee.

The two sites are the North Railroad Avenue Plume Superfund Site (NRAP), which has been in active cleanup for more than 10 years, and the Calle Chavez Plume which is more recent. Both sites are overseen by NMED’s Groundwater Quality Bureau.

Roose said there has been a lot of activity on the NRAP site for quite some time. In 2019, there was a transition from EPA funding the majority of the cleanup to the state funding the majority of the cleanup.

“Whenever NMED takes on more financial responsibility for a Superfund cleanup in the state of New Mexico, we will come to the legislature and seek funding for that and we are fully funded for the next few years for cleanup costs at this site and any other Superfund site in the state that we’re actively engaging in the cleanup and there’s not a responsible party available to be paying for those costs. So this is a site where first EPA and now the state are covering the cost for lack of a responsible party with the ability to pay for that,” Roose said.

She said the cleanup goals for the plume are to restore the groundwater.

“This is right in the center of Espanola underneath the Plaza area and our goal is to clean up the groundwater to less than drinking water maximum contaminant levels. Espanola is a community that is extremely limited in their drinking water source supply and the fact that there’s a contaminated plume right underneath the city is major factor for them in thinking about their water supply,” she said. “Also  it’s important to know that this falls within the exterior boundaries of the Santa Clara Pueblo and achieving the cleanup to maximum contaminant levels under the drinking water standards would meet Santa Clara Pueblo’s water quality standards as well. They have been involved from the time that the Superfund process got initially underway.”

Roose noted that there has been a significant amount of progress on the plume from 2009 to 2020 with implementation of the remedy that was selected to clean up the contamination.

“The pollutants that we’re cleaning up are tetrachloroethylene which is commonly referred to as PCE, a chemical that has been commonly used in a number of industries including laundry and dry cleaning. Since 2020, we have seen a lot of improvement in the source area and concentrations of the PCE have decreased from as high as 4,900 micrograms per liter down to 51 micrograms per liter. There’s still work to do but we’re very encouraged by the progress we’re seeing and are generally on track for the overall timeline for the site,” she said.

Roose said it’s important that NMED also look at the surface area above the plume because of the possibility of harmful vapors coming out through the top of the rock surface into dwellings and businesses where it is trapped in an indoor area. She said NMED regularly monitors indoor air in buildings and businesses in the area of the site and that the indoor concentrations remain protected at this time.

Roose showed maps indicating the changes in size and shape of the plume which she said are an indication of the progress being made in cleaning up those deeper zones.

“There’s been some stubborn spots and we are since 2020 using some additional pilot techniques to try and accelerate cleanup in some of the spots that have been harder. We hadn’t  seen the level of progress and results that we want to see and so far are seeing some real improvement there and will have more study results coming out this fall-winter and will be providing updates to the community as we go forward,” she said.

Roose noted that the next round of injections for the treatment remedy is coming next year.

“This is an ongoing process. We are still years out from total cleanup, which was understood when we selected the remedy in the 2000s but we are going to keep at it and keep communicating with community each step of the way,” she said.

The second plume in Espanola, the Calle Chavez Plume, also has some of the same contaminants – PCE and TCE from what NMED believes to be a different dry cleaner that’s still in operation right along  Paseo del Norte.

“This is the business that NMED believes is the source from studies done so far. This plume was discovered by NMED and EPA scientists who were actually working on the NRAP Superfund site and found contamination underground where they weren’t quite expecting it based on where they understood the Superfund site contamination to be,” she said. “We did several years of additional research and review including new wells so that we could figure out where things were coming from, levels of contamination, etc. We ultimately identified in late 2019 that this was a separate plume from a separate source and we at NMED have been working under our authority through the Water Quality Act and regulations to require this dry cleaning company on Paseo del Norte to clean up the site through our state abatement program. It’s a state regulatory approach similar to Resource Conservation Recovery Act. And currently the dry cleaner is working at that process.”

Roose said the Calle Chavez Plume has been a very active project for NMED this year and that there has been lots of progress with NMED approving a Stage 1 Abatement Plan.

“It means the company is involved in working towards abating the pollution – mapping it out, investigating the contamination, where is it, how much is it, what are the boundaries, how deep is it,” she said. “It’s a very data driven process. When we’re dealing with cleaning up these types of sites, it may seem like it’s taking a really long time, but we can’t rush the science. We need to make sure we’re getting the right amount of data from the right locations in this community and really ensuring that we have reliable information on which to base the decisions to shift into cleanup in Stage 2 of the process. The facility will propose a cleanup strategy and NMED will review that proposal and ultimately when we approve a Stage 1 Abatement Plan after public comment, then we are essentially In the position of knowing what’s going to happen next to clean it up.”

Roose said NMED is going to be working very closely with community members.

“We have lots of good dialogue open now with local officials and concerned citizens and very regular dialogue with Governor Chavarria of the Santa Clara Pueblo and his team to ensure that they are actively informed and engaged in the cleanup process as we move forward,” Roose said.