Lehigh Southwest Cement Company has announced plans to install an innovative mercury reduction system at its plant in Tehachapi. The plant will begin installation of a state of the Art Activated Carbon Injection system in early 2013 with the goal of completing the project later in the year.
Mercury emissions from the manufacturing process are primarily attributable to the naturally occurring concentrations found in the local limestone the key material used to make cement, according to Plant Manager Alan Rowley.
At one time there were several mercury mines in the Tehachapi area. Traces of mercury can be found in other local components such as silica. The plant has already taken steps to replace that material with silica purchased from an outside source, he said.
The system has been installed in two other plants un the United States including its plant in Cupertino. That plant was the first cement plant in California to apply the technology. The plant has experienced a 90 percent reduction in mercury emissions. The company expects a similar reduction at the Tehachapi plant once the system is in place.
"Leigh Southwest Cement Company is serious about environmental substantiability and we are committed to working closely with the communities where we operate," Rowley said. "The planned implementation of this mercury reducing technology clearly demonstrates this commitment and reflects our focus on minimizing the environmental impact of our operations."
Lehigh Southwest Cement Company's operations are highly regulated by federal, state and local agencies which monitor the facilities frequently. In 2009, in response to a request from the East Kern Air Pollution Control District in 2009, a leading independent environmental consulting firm prepared a Health Risk Assessment for the Tehachapi plant. The publically available report, published in 2010 concluded that health risks related to mercury emissions from the plant were below notification levels established by the district, Rowley noted.
Craig Mifflin, manager of environmental and public affairs for Lehigh, also gave a presentation at the City Council meeting on Nov. 19, noting that the company is working to obtain a conditional use permit to burn trash in place of coal in its Smith kiln. Recycleable packaging, paper, cardboard, etc. is shredded and converted in to an engineered fuel, he said, a common practice in Europe (converted municipal waste into fuel).
A test of the system was conducted about a year ago and it worked exceptionally well, Mifflin said. Stack testing was done at the same time to test for pollutants that were coming out stack. Well over 20 different pollutants were tested for and there were no surprises. Nothing come up that was out of the ordinary or elevated the plant's emissions, he noted.
"This could help in extending the life of the existing land fill and reduce the cost of going to other land fills," Mifflin said. "It provides a safe alternative to land fills and additionally, instead of spending our money on bringing in coal from Utah, we can spend some of that money here locally. There are also other alternative fuels that we intend to explore including agricultural by products, which is biomass urban wood waste and shredded tire chips."
He said a Notice of Preparation for the EIR should be issued by Kern County planning soon.
"After we receive the conditional use permit we have to purchase the equipment and construct it," he said. "If all goes well we should be on line by next fall." Photo by Ed Gordon
The Lehigh Cement plant near Tehachapi is preparing for a mercury reduction project.