A Thai petrochemical and refining company is considering Belmont County as a possible site to build a refinery that would make ethylene and other plastics from shale gas.

PTT Global Chemical, Thailand's largest integrated petrochemical and refining company and the Marubeni Corp., a Japanese investment adviser, have discussed the project for the last two years with JobsOhio and its regional arm, the Appalachian Partnership for Economic Growth.

If built, such a refinery, often called a "cracker," could cost several billion dollars, create thousands of construction jobs and hundreds of permanent jobs.

Before choosing Belmont County, the developers looked at sites in the entire region where gas producers have been drilling wells in Ohio, West Virginia and Pennsylvania. The prolific production of these wells has led to steep declines in the price of regional gas, and for now, a slowdown in further drilling.

A final decision will take the next 12 to 16 months, said JobsOhio, as PTT and Marubeni complete engineering designs and obtain state and local permits.

Shale gas includes a mixture of methane and other gases such as ethane, propane and butane. While methane is used as a fuel, the other gases, particularly ethane are broken down, or "cracked" in refineries to produce ethylene and similar hydrocarbons that are the "building blocks" of the polymer and plastics industries, which produce everything from plastic parts to consumer packaging, textiles and pharmaceuticals.

An Ohio cracker -- or one in West Virginia or Pennsylvania -- is considered crucial to accelerating growth of the region's plastics industry. As many as three other companies, including Shell Chemical, have been considering building crackers here.

Gov. John Kasich made the announcement Wednesday that Belmont County has been tentatively chosen.

"We are one step closer to landing a new, multi-billion-dollar investment in eastern Ohio, and that's exciting news for our state, the region and Belmont County," said Kasich. "There is more work ahead before final decisions on this project are made, but I know our Ohio team will do everything we can to bring it fruition."

Dr. Kongkrapan Intarajang, executive vice president of International Business Relations for PTT Global Chemical, said working with Ohio has been a positive experience.

"While we have not yet made final decisions on this investment, we will continue to work with Gov. Kasich, JobsOhio and all of the local partners in an effort to make our vision a reality. We look forward to moving this project into the next phase."