Carbon dioxide emissions from large facilities in Bartholomew County released about 113,000 metric tons into the air in 2014, according to an Environmental Protection Agency database. That volume ranks Bartholomew near the midpoint among Indiana’s 92 counties, with 43 generating more industrial carbon dioxide pollution and 48 generating less.

The two biggest individual sources of carbon emissions in Bartholomew County are its landfills. The Walesboro landfill emits 59,386 metric tons of carbon dioxide emissions per year, followed by the Petersville landfill at 28,452 metric tons per year, which is full and no longer accepting material.

The only local industry to exceed 25,000 tons of carbon dioxide per year, the benchmark emissions level set to make the Environmental Protection Agency’s greenhouse gas watch list, is Enkei America, which produces wheels for popular car brands such as Honda and Nissan.

All are operating within acceptable emissions ranges with no penalties from either Indiana or the federal government.

Enkei, the first Japanese-based company to open in Bartholomew County in 1985, has significantly decreased its carbon footprint since then, said Ron Thompson, environmental health and safety manager at the company’s Walesboro plant.

In the early 2000s, all of the company’s oil-burning furnaces were replaced with much cleaner natural gas devices. More recently, solvent-based paints have been removed from the production process, replaced by sturdier, cleaner powder coat, Thompson said.

Not only have these changes lowered carbon dioxide emissions, they have also impacted other forms of carbon pollution.

In 1996, the company was permitted to release about 98,000 tons of volatile organic compounds into the air, Thompson said. By 2014, the company had managed to reduce this amount to less than 35,000 tons per year.

Volatile organic compounds are a group of chemicals derived from partially burned organic matter, including fossil fuels. According to the EPA, exposure to these pollutants may cause respiratory problems and increased risk of cancer.

Melting large quantities of metal — as Enkei does — requires extreme heat, and extreme heat involves burning fuel, Thompson said.

Enkei tries to work as efficiently and cleanly as possible, and in recent years enclosed all of its holding vats so less energy escapes during the melting process. But the laws of thermodynamics and technology limit what is possible, Thompson said.

“We certainly want to reduce our emissions more. But unless technology changes, I don’t see that happening,” he said.

Lower emissions means less money spent on fuel, which means higher profits, Thompson said.

Until a newer, more efficient natural gas furnace is invented or some alternative foundry process is designed which uses no fuel, there is little the company can do to decrease its carbon production, he said.

Enkei is currently just above the EPA reporting limit as a major industrial emitter of carbon dioxide. The facility released about 26,000 metric tons of carbon dioxide in 2014, primarily from natural gas furnaces used to melt aluminum ingots for casting into wheels. Under its Title V air quality permit, the company is legally allowed to emit up to 38,600 metric tons of carbon dioxide per year.

The Enkei facility has hovered in that range for the past five years, occasionally dropping below the reporting limit and occasionally increasing slightly.

This fluctuation is directly tied to the number of wheels produced by the company, Thompson said.

The more wheels sold, the greater the pollution. When fewer wheels are cast, pollution decreases.

While he does not yet have specific numbers for 2015, Thompson said he suspects strong sales may have driven carbon dioxide levels a little higher.

Currently, 60 percent of Hondas and 55 percent of all Nissans in the United States carry Enkei wheels, Thompson said.

As sales of these cars have grown, so has demand for Enkei wheels. The company now ships about 230,000 individual wheels per month from its Bartholomew County facility.

Efforts at Cummins

In comparison, Columbus diesel engine maker Cummins Inc. — the county’s largest employer — emits a total of 200,000 metric tons of carbon dioxide across its 22 facilities in Bartholomew County — an average of about 10,000 tons per facility.However, the EPA only tracks facilities emitting more than 25,000 tons of carbon dioxide per year, so no individual Cummins facility in Columbus appears on the EPA’s greenhouse gas watch list.Laurie Counsel, environmental and compliance director for Cummins, said each company’s specific product type probably accounts for the difference in emissions. Most of the major Cummins operations in Bartholomew County focus on assembly, testing or design. The company no longer does large-scale foundry work within the county.

Most of the fuel consumed by Cummins is used to power air compressors, water chillers and steam boilers which drive other devices. This gives Cummins flexibility in looking for areas of efficiency, Counsel said.

With complex machines, small adjustments and innovations make a significant difference, she said.

For example, by replacing two outdated boilers in the company’s Fuel Systems plant, Cummins was able to reduce its emission by 543 metric tons per year. One new chiller at the company’s test center resulted in a carbon dioxide reduction of 2,285-metric tons per year.

These are just a few of the company’s ongoing green initiatives, Counsel said. About 99 percent of carbon dioxide emissions attributable to the company come from its products, not its manufacturing techniques, Counsel said.

Consequently, many of the global manufacturer’s greenhouse gas initiatives focus on building cleaner, more efficient diesel engines, Counsel said.

Such efforts support one of the company’s five missions: “Demanding that everything we do leads to a cleaner, healthier, safer environment.”

Landfill emissions

At landfills, natural gas and carbon dioxide are natural byproducts of decomposition.The result is release of nearly 87,000 metric tons of carbon dioxide per year between both Bartholomew County landfills, EPA records said.At the moment, there is little the county can do to reduce these numbers, said Heather Siesel, director of the Bartholomew County Solid Waste District.

In the long term, county officials are considering a network of tubes running through the landfill which would collect gases such as carbon dioxide, Siesel said. These would be piped to a central location, where they could be sold as usable products.

But it is too early in the Walesboro landfill’s life cycle to install such a system, she said. The current landfill opened in 1998, with most of the waste deposited within the past 15 years. The trash simply hasn’t decomposed enough to produce usable levels of gas.

The young landfill also needs to absorb a lot more trash before it is ready for a gas-collection system, Siesel said.

Placed too early and the county will find itself ripping out and moving the pipes every few years. As the topography changes, so does ideal placement of gas collection tubes.

But wait a decade or two and the landscape will have settled, Siesel said. The deeper layers of garbage will be stable and installation will be more permanent.

Greenhouse gas sources

The Environmental Protection Agency’s greenhouse gas watch list includes large facilities that emit at least 25,000 tons of carbon dioxide per year.  Three Bartholomew County entities exceeded that amount in 2014, the most recent year available.

Walesboro landfill: 59,386 metric tons per year

Petersville landfill: 28,452 metric tons per year

Enkei America: 26,149 metric tons per year

Source: EPA Greenhouse Gas Reporting Program