Editor's note: This story has been update to fix broken art on this article.

HARRISBURG -- In May 1966, Columbia Gas and the federal Atomic Energy Commission presented an audacious plan to a representative of the Governor's Science Advisory Committee: A proposal to detonate a nuclear bomb more powerful than the one dropped on Hiroshima 3,500 feet below north-central Pennsylvania.

"At the present stage, this proposal involves a detonation of a 'shot' of perhaps 20,000 tons TNT equivalent at a location on the boundary between Centre and Clinton counties," wrote Louis Roddis Jr., the governor's representative in his report.

The goal was to use the nuclear blast to create a chamber that could then be filled with pressurized natural gas. Named Project Ketch, the proposal was an offshoot of another nuclear explosive-powered idea, Project Gasbuggy, which called on increasing natural gas production by detonating nuclear bombs underground to fracture rock deposits -- nuclear fracking.

From the get-go, however, Roddis noted there would be challenges to the proposal. Safety considerations, he wrote, fell under three categories: seismic problems, immediate radioactivity problems, and long-term radioactivity problems.

And then there were questions regarding the public's willingness to allow the detonation of nuclear weapons (even underground) near populated areas.

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In his report, Roddis noted that "there is a distinct public relations problem since the northeastern United States is not as accustomed to either earthquake shocks or nuclear test shots as is the southwestern United States."

The public relations "problem" would ultimately scuttle Project Ketch (and later, nuclear bomb fracking) but not before the state, Columbia and the AEC spent a year studying the project. And interestingly, many of the concerns and opportunities raised by those studies would come to fruition -- albeit not through the agency of the atom bomb.

Project Ketch was a 50-year-old proposal to use a nuclear blast to create a chamber which could then be filled with pressurized natural gas.

Toward the end of the 1950s the federal government had proposed a new series of projects to harness the power of the atom bomb for peaceful purposes -- Project Plowshare. Proposals for Plowshare included detonating bombs to widen the Panama Canal, connect underground water supplies in the Southwest and create an artificial harbor in Alaska.

Few of the proposals ever got off the ground. But one of the few that did was a project put forward by the El Paso Natural Gas Company to detonate nuclear weapons in shale rock formations to see if it would subsequently allow for natural gas extraction. Blasting shale rock formations with nukes would theoretically allow the company to extract more natural gas, potentially revolutionizing the energy industry.

But if gas production were to increase, companies would need a place to store it -- hence Columbia's interest in using a nuclear device to create a natural gas storage facility. Columbia was proposing a single test blast between the towns of State College and Renovo in Sproul State Forest. Theoretically the blast would create a hollow chamber under the ground, capable of holding pressurized natural gas.

If the two tests were deemed successful, and if the use of nuclear weapons for natural gas production purposes were approved, proponents envisioned a future of cheap (possibly even free) natural gas for heating and electrical generation purposes created, according to an article in the New York Times, by "hundreds of underground [nuclear] blasts."

***

As 1967 dawned, Columbia, the federal government, and the state continued to quietly work on Project Ketch behind the scenes. In May, representatives of the various groups met in Harrisburg. Project Gasbuggy had been given a green light and was scheduled to test later that year.

Project Ketch had yet to be officially authorized, but according to a memo from the Department of Commerce to the governor it was proposed that Columbia Gas and associated scientists move forward with geological and safety evaluations for the project.

A cross-section of earth and the location of the Project Ketch project.

The entire project was estimated to cost around $6 million and take nearly three years by the time planning, detonation and cleanup operations were complete and gas could be pumped into the reservoir.

Various state agencies moved to approve Columbia's request to undertake the feasibility study -- and signaled that if the results were positive, they would look favorably upon the detonation of the device.

A letter written that year by state Secretary of the Department of Forests and Waters Maurice Goddard to state Secretary of Commerce Clifford Jones listed the benefits that underground nuclear blasting could bring to the commonwealth. They included economic growth, jobs, state budget revenue through ground leases and allowing the state to "achieve an industrial first and remain in the forefront in the harnessing of nuclear energy for peaceful purposes."

Few state agencies noted reservations with the plan. A letter from the state's Game Commission approved phase one of the project, but asked that "news releases should include information to quell the fears of sportsmen that this project, if carried to completion, would have damaging effects to hunting or fishing in the immediate area or nearby areas."

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One agency that did question the project was the Pennsylvania Fish Commission, where staff members who reviewed the proposal lodged questions about the unfavorable effects the detonation could have to subsurface water conditions and contamination from radioactive materials.

In August, Gov. Raymond Shafer approved the use of the site for the phase one study. Phase two, according to government memos, was detonation.

"Permitting Columbia Gas and the Atomic Energy Commission to proceed with phase one does not grant permission to detonate the nuclear device," state officials wrote. "Without the approval by the Commonwealth, the shot will never take place."

***

News that Project Ketch was on the drawing board leaked in early 1967. The public's reaction -- especially in nearby Renovo, 12 miles from the proposed blast site, was not favorable.

Opponents launched letter writing campaigns and formed advocacy groups.

An example of an anti-Ketch letter from the Pennsylvania State Archive collection. Public sentiment against the project was citied by news reports of one of the main reasons it was stopped.

In response, the parties involved in the proposed test noted that "the importance of the public relations problem implied that a definite public relations program should be established as soon as possible" and proposed focusing on the safety and technical portions of the project as opposed to the economic implications.

Even as public opposition grew, Gasbuggy was being scheduled for mid-November of 1967. A memo to John Tabor, state Secretary of Interior, discussed sending a delegation to be present at the detonation or "shot" in 1960s nuclear parlance.

"The major benefit to shot visitors will be to feel the nature of the shock at a distance of five miles," the memo stated. Those visitors, it was suggested, might include the mayors of Renovo and Lock Haven, area legislators, county commissioners and others.

As scientists and communities debated safety, and corporate developers considered optics, there were other concerns among state leaders. In echoes of the future there was a substantial debate occurring as to whether or not a successful Project Ketch execution (and possible further usage of nuclear devices for fracking and the creation of gas holding tanks) would put the state's coal industry at a competitive disadvantage.

At the time however, the largest threat to the coal industry was not believed to be natural gas but rather the burgeoning nuclear power industry (the Three Mile Island incident would not occur for another 12 years).

Somewhat ironically, 50 years later the nuclear power industry itself is looking for a lifeline while the coal industry has been hammered by cheap natural gas produced in Pennsylvania through the non-nuclear fracking of the Marcellus Shale.

***

On Dec. 10, 1967, a 29-kiloton nuclear device was detonated underground in rural northern New Mexico. It was, the New York Times reported, "the world's first government-industry detonation of a thermonuclear device for peaceful purposes."

Scientists from the Atomic Energy Commission said it would take a few years to discover if the test had indeed been successful -- and to measure how much radioactivity would linger in the natural gas being produced at the site.

Back in Pennsylvania, work on the safety and geological study for Project Ketch was moving forward -- although it would be dead in less than a year. In July, Columbia Gas sent a letter to Gov. Shafer withdrawing the project.

In a story July 6, 1968, in the New York Times, a company spokesman said the proposal was withdrawn following public criticism.

"However, the company said it had not dropped the venture, called Project Ketch, and would look for a proper site on private land in or outside of Pennsylvania," the newspaper reported, although Columbia appears to have shelved the proposal entirely after Ketch failed.

The following January, Howard Boyrd, Chairman of the El Paso Natural Gas Company, said the initial results from Gasbuggy had been so encouraging that El Paso was seeking a second test in the Rocky Mountain area "to provide additional data on the extent of fracturing and on radioactivity levels."

Two more nuclear fracking blasts, Project Rulison (1969) and Project Rio Blanco (1973), followed. However, the radioactive contamination that resulted from the blasts was deemed to be too extensive for the project to be truly feasible. Scientists at the Atomic Energy Commission reported that after studying the results from Gasbuggy and Rulison that using nuclear bombs to stimulate gas production would result in increased radiation levels among residents heating their homes using gas produced through nuclear fracking.

The idea was shelved and the Plowshares Project itself was wound down shortly after the Rio Blanco blast. Natural gas extraction would continue to develop in a less spectacular manner.

However, in a final echo of things past, a recent study by Duke University researchers found radioactive materials in Pennsylvania waterways downstream from waste water treatment plants that accept conventional oil and gas drilling waste water.

The radioactivity is not tied to fracking, nuclear or otherwise, but rather to trace amounts of naturally occurring radium contained in well waste water.