A group of Catholic nuns in Pennsylvania is resisting plans to build a $3bn pipeline for gas obtained by fracking through its land by building a makeshift chapel along the proposed route and, citing religious freedom, launching a legal challenge.

The Adorers of the Blood of Christ order has filed a complaint against the Federal Energy Regulatory Commission (FERC) in an attempt to keep the pipeline off their land.

The nuns' lawyers argue in court papers that a decision by the FERC to force them to accept the pipeline is 'antithetical to the deeply held religious beliefs and convictions of the Adorers'.

For the Adorers, an order of 2,000 nuns across the world which was founded in 1834, protection of the environment is central to their mission. The plan for the pipeline 'goes against everything we believe in – we believe in the sustenance of all creation', Sister Linda Fischer, 74, told the Washington Post.

The website for the 183-mile Atlantic Sunrise pipeline says it is 'designed to supply enough natural gas to meet the daily needs of more than 7 million American homes by connecting producing regions in northeastern Pennsylvania to markets in the Mid-Atlantic and southeastern states'.

An extension of the Transco pipeline, which runs more than 10,000 miles from from Texas to New York, it will carry gas extracted from the Marcellus shale region since fracking was permitted by the state.

The company building the pipeline, Williams, wants to pay farm owners to allow it to dig up land, install the line, and return the land to farm use. The company has offered compensation for lost crops and regular inspections to establish whether the pipeline affects agricultural output.

Around 30 landowners who refused to do a deal with Williams now face being forced to comply by a FERC order.

There is a plan for a section of the pipeline to run underneath a strip of land owned by the Adorers in West Hempfield Township, Lancaster County, and leased to a local farmer.

Earlier this month, with 300 people in attendance, the nuns dedicated an outdoor chapel at the site, consisting of some wooden benches and an arbour surrounded by corn.

'We just wanted to symbolise, really, what is already there. This is holy ground,' said Sister Janet McCann.

Lancaster Against Pipelines, a local activist group, has pledged to mount a round-the-clock vigil at the chapel if the court rules against the nuns.

In 2005, the nuns adopted a 'land ethic' upholding the sacredness of creation, which says the earth is a 'sanctuary where all life is protected' and which must continue to be protected for future generations.

Their lawyers have told the court that the nuns' religious beliefs include 'educating and addressing important issues of social and environmental justice, such as poverty, war, racism and global warming that separates humans in a way that the Adorers do not believe mirrors their hope for the Kingdom of God'.

The nuns' conviction that the earth is part of God's creation 'compels the Adorers to exercise their religious beliefs by, inter alia, caring for and protecting the land they own as well as actively educating and engaging on issues relating to the environment, including the current and future impact on the earth caused by global warming as the result of the use of fossil fuels'.