More to discover: Geophysical study planned at Camp Security

A Revolutionary War-era prisoner of war camp might yield more information about York County's history after an upcoming geophysical study.

For the past three years, Friends of Camp Security has been looking for evidence of a stockade built on the site, located in Springettsbury Township, said Steve Warfel, an archaeologist from the historic preservation organization.

The group knows it's there, he said, based on memoirs of prisoners who helped build it and pension records from York County militia that guarded the prisoners.

Senior archaeologist Steve Warfel, left, of Friends of Camp Security, instructs volunteer Matt Oberdick, of Springettsbury Township, during an archaeological dig on the undeveloped site of the Revolutionary War prison camp in Springettsbury Township, Wednesday, June 8, 2016. Dawn J. Sagert photo

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Though artifacts that point to the stockade have been found in recent years, archaeologists are still hoping to find its structural remains — namely, the trench dug to support wooden stockade posts.

With a geophysical survey of the land, Friends of Camp Security believes it might be able to find it, Warfel said.

The organization is teaming up with students, faculty and staff from Shippensburg University's Department of Geography-Earth Science to test part of the area with ground-penetrating radar and electromagnetic and soil resistivity methods, according to a news release.

The non-invasive tests will determine if there have been disturbances in the soil created by people living in a concentrated area.

Ground-penetrating radar sends radio signals in the ground that bounce off whatever they hit and penetrate the soil 10 to 15 feet beneath the surface, Warfel explained. If the signal indicates it traveled much deeper in a certain area, it could indicate a trench.

The electromagnetic method looks for changes in magnetic characteristics, which could indicate scorched earth from a firepit or cooking hearth, and the soil resistivity monitors unusual signatures of electrical currents traveling through the soil, he said.

If the three methods align in their results, there's a good chance the Friends of Camp Security will find the trench or latrines or wells thought to be dug within the stockade.

"Once we find evidence of the trench, we can come up with an understanding of how large the stockade was," Warfel said, noting they expect it to be about 2 acres in size.

"(We) can't take all soil off of 16 acres and look at it all," he said, so this process narrows down where archaeologists will dig in their follow-up investigation.

Because the findings cannot determine when changes in the soil occurred, a dig is required to see if they are from recent years or from during the camp's operation.

Assistant archaeologist John Crawmer, of Thomasville, holds a piece of French musket flint, just one of the many artifacts found thus far during Friends of Camp Security's archaeological dig at the former site of the Revolutionary War prison camp in Springettsbury Township, Wednesday, June 8, 2016. Dawn J. Sagert photo

The site of the testing is not far from the western boundary of the camp, which will be the site of a sewer line for Springettsbury Township, which also owns Camp Security Park. 

"We certainly had tremendous concerns about it when we first heard about it," Warfel said of the sewer line, which falls within a 200 yard radius of where artifacts were discovered in 1979.

But since the Camp Security property is protected by law under the State Historic Preservation Act, archaeologists were required to do a dig in 2014 — when the township first applied for permits for the sewer project — to see if there was evidence of historical findings within the footprint of the project.

Since there were no indications of historical findings, the township was cleared to go forward with construction.

The Friends of Camp Security organization has no intention to rebuild the camp, but if they know where the stockade stood, they can mark it for future park visitors.

"This could be a very rare opportunity to understand more about the nature of these early prison camps," Warfel said. "It's a matter of understanding ... our historical past."

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The testing will be done this winter, with a final report by the end of March 2018.

The schedule of the dig is uncertain, Warfel said, because it depends on the availability of the university and the weather. Moisture on the ground gives false readings, so the group prefers four days of dry weather to allow the soil to drain before testing. 

Friends of Camp Security is looking for donations for the subsequent archaeological dig. Each dig lasts about six weeks and costs close to $20,000. The geophysical survey additionally costs about $7,000. 

Reach Lindsay C. VanAsdalan at or on Twitter at @lcvanasdalan.