Power plants install emissions controls

James Fenton
Nathan Tohtsoni, an Arizona Public Service employee, points to an area at the Four Corners Power Plant in Fruitland, as seen Oct., 12, where retrofitting has begun to allow the plant to meet federal haze regulations.

FARMINGTON — Both Farmington-area power plants have begun installing pollution controls to comply with federal regulations intended to reduce atmospheric haze.

The multi-million-dollar retrofitting projects underway at both coal-fired power plants is to be completed by 2018. The plants — San Juan Generating Station and Four Corners Power Plant — are located 20 miles west of Farmington.

This summer, the Environmental Protection Agency finalized additional portions of the July 1999 regional haze rule, which requires emission controls known as "best available retrofit technology," or BART, be added to industrial facilities that emit air pollutants reducing visibility by causing or contributing to regional haze.

The retrofitting work aims to reduce emissions, especially of pollutants like nitrogen oxides, sulfur dioxides and particulate matter, which impact visibility.

The federal Clean Air Act sets the goal of returning national parks and wilderness areas to “natural visibility levels” by 2064, according to an EPA press release.

The pollution controls will also help the state comply with the EPA’s Clean Power Plan, which aims to reduce carbon pollution from power plants to address climate change.

Power plants such as Four Corners Power Plant and San Juan Generating Station are the largest industrial sources of carbon dioxide, a potent greenhouse gas.

Four Corners Power Plant, Fruitland

The plant, owned and operated by Arizona Public Service Company, or APS, shut down its three older generating units in December 2013. Those units are expected to be demolished and removed from the plant by 2017.

This area near the Four Corners Power Plant's generating units 4 and 5, seen on Oct. 12, is where retrofitting will occur to allow the plant to meet federal haze regulations.

The remaining two units, Units No. 4 and No. 5, which are two separate flues housed together in one common stack, will be retrofitted with pollution controls starting this week.

The work, which began several years ago, involves the installation of pollution controls, called SCRs, or selective catalytic reduction technology. The technology and installation will cost approximately $635 million and is expected to be operational by July 2018. The work will require two 95-day outages at the plant. Those outages are slated to occur in fall 2017 and spring 2018, according to David Hansen, APS vice president of fossil generation.

“We believe at the end of that process, including the shutdown of Units 1, 2 and 3, the total (nitrogen oxide) emissions for the site, in comparison with what it was several years ago, will be reduced by about 86 percent,” Hansen said.

San Juan Generating Station, Waterflow

The San Juan Generating Station, which is owned and operated by majority owner Public Service Company of New Mexico, or PNM, is enmeshed in a case before state regulators over whether the utility’s compromise plan to shutdown two of the plant’s units and retrofit two others is acceptable.

PNM's plan includes the installation of nitrogen oxide emissions reduction technology on Units No. 1 and No. 4 by 2018 and retiring Units No. 2 and No. 3 by the end of 2017.

The plan was developed as a compromise after plant officials said meeting federal haze regulations under the federal Clean Air Act at the plant would be too expensive and result in the utility closing the station.

Both units at the plant will receive selective non-catalytic reduction, or SNCR, which reduces nitrogen oxide emissions.

The generating station has already completed retrofitting Unit No. 1 this year. The plant began “outage” work retrofitting Unit No. 4 last week.

Maureen Gannon, executive director of environment and safety at PNM, said the work will bring the coal-fired power plant into compliance with state and federal regulations.

“We're moving forward to comply with the regional haze rules,” Gannon said. “What's been provided to the PRC is the right plan, the most cost-effective plan that will reduce the plant's carbon footprint, which will be a huge step for the state.”

James Fenton is the business editor of The Daily Times. He can be reached at 505-564-4621.