Noranda Alumina said they should know in a few more weeks if its Gramercy plant is still releasing mercury into the air, and if so, how much and from where.

Last year, plant officials reported to the state Department of Environmental Quality that workers found about 2 ounces of liquid mercury during a maintenance operation and also told DEQ last spring that they believed the plant was releasing small amounts of mercury into the air.

Earlier this year, Noranda officials reported they believe the 55-year-old plant has been emitting mercury into the air for decades undetected and unpermitted.

Noranda is now in the process of sampling for airborne mercury throughout the 3,300-acre site fronting Airline Highway in an effort to get an air permit from the DEQ for emissions of the material.

“We care about the community. Our families are here; we live and work here,” said Noranda Alumina President John Habisreitinger, a Louisiana native.

On Thursday, Noranda officials spoke with residents at a meeting hosted by St. James and St. John the Baptist parishes governments.

A persistent question at the meeting was whether DEQ or Noranda had taken and tested samples of soil at the plant and in the area.

Representatives of both said soil sampling was not required in the air permitting process underway.

After the meeting, Norman Macmillan, owner of Laura Plantation in nearby Vacherie, said he was one of the people who had originally gone to the St. James Parish Council with his concerns about mercury emissions at the plant.

“I requested that soil samples be taken,” Macmillan said. “My concern is that over the years, (mercury) has accumulated in the soil.”

“We’re going to keep pushing and pushing to get the soil samples,” Macmillan said.

Mercury in high concentrations can harm the human nervous system, heart, kidney, brain and lungs.

The Noranda facility, which produces alumina, a material used to make aluminum, already has another type of air permit from the DEQ for its areas in the plant that handle the raw material used in production, a reddish soil high in aluminum oxide called bauxite, which has traces of mercury, a naturally occurring element.

Noranda also has a water permit that requires groundwater monitoring at 47 wells at the plant, said Cheryl Nolan, an administrator with the DEQ.

Sampling at Noranda has shown that concentrations of mercury are well below groundwater protection standards in the 10-foot well zone and not detected at all in the 50-foot well zone, said Nolan, one of several officials with the DEQ on hand at the meeting Thursday evening at Lutcher High School.

Noranda, which produces about 1.2 million metric tons annually of alumina, has been operating in Gramercy since 1959.

In its manufacturing process, the bauxite, which Noranda receives at its dock from mining operations in Jamaica, is mixed with caustic soda and, under high temperature and high pressure in a smelter, produces alumina.

In March 2014, Noranda reported to DEQ that 2 to 3 ounces of liquid mercury had been found during routine maintenance of an industrial heater.

A month later, Noranda determined that the bauxite at the plant was a possible primary source of mercury, and a secondary source was possibly a caustic used in the manufacturing process, Nolan said.

“The facility identified up to 36 potential mercury emission points,” Nolan said.

In June 2014, DEQ received a request from Noranda, dating from May, for a interim limit of 250 pounds per year of mercury air emissions.

This past spring, Noranda Alumina officials told DEQ they thought mercury was being released into the air from steam vents tied to plant heat exchangers.

The DEQ told Noranda it would have to demonstrate compliance with the state’s toxic air pollutant ambient air standards before that interim 250-pounds-per-year limit could be set.

This year, in February, DEQ issued to Noranda a compliance order and notice of a potential penalty that called for, among other things, submitting a mercury modeling protocol for DEQ approval and conducting air modeling exercises.

In March, Noranda changed its request for an interim limit of 250 pounds of mercury emissions per year downward to 20 pounds a year, after getting additional information from similar facilities.

After that, DEQ revised its original compliance order, asking the company to submit a written protocol for mercury measuring activities and to conduct those measurements, before applying for an air permit.

That protocol has been approved, and the plant is in the process of sampling for mercury emissions at various places in the plant over four weeks, Nolan said.

A state-accredited laboratory is performing the analysis of the samples.

“Based on results of sampling, DEQ may require stack testing,” Nolan said.

She also noted that DEQ’s mobile air monitoring lab had tested for air mercury emissions near the plant in March and in May.

The state’s air quality standard for an eight-hour average for mercury is 1.19 micrograms per cubic meter, Nolan said. The DEQ mobile lab near Noranda found an eight-hour average for mercury of 0.00051 micrograms per cubic meter.

“We are working with DEQ through a detailed, collaborative process,” said Charley Sellards, the environmental health, safety and security manager with Noranda. “We are currently collecting and analyzing material throughout the site per an established protocol approved by DEQ.”

“We expect to have the results in the next few weeks,” Sellards said.

Follow Ellyn Couvillion on Twitter, @EllynCouvillion.