PHILADELPHIA — Both former President Donald Trump and Vice President Kamala Harris emphasized their positions on fracking during Tuesday’s debate on ABC News.

The term is an abbreviation for hydraulic fracturing, a process of extracting gas or oil from deep underground using a mixture of water, sand and chemicals under high pressure to break up rock.

Pennsylvania is the second largest producer of natural gas in the country.

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Both candidates say they will not ban fracking.

Harris was asked about her 2019 presidential bid, when she came out strongly in favor of a ban.

“I will not ban fracking,” Harris clarified during the debate. “My position is that we need to invest in diverse energy sources so that we reduce our dependence on foreign oil.”

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“Fracking. She’s been against it for 12 years. She’ll never allow fracking in Pennsylvania. If she wins the election, it’s the end of day one,” Trump refuted.

Federal energy statistics show that U.S. production of natural gas and crude oil reached record highs last year.