UNIVERSITY PARK, Pa. — In 2013, Penn State launched the Pennsylvania Mine Map Atlas, an interactive online database of Pennsylvania’s underground mines. Managed by Pennsylvania Spatial Data Access (PASDA), which is a part of the Institutes of Energy and the Environment, in partnership with the Pennsylvania Department of Environmental Protection (PA DEP), the Pennsylvania Mine Map Atlas houses over 100,000 high-resolution scans of original mine maps, which are overlaid onto a modern map of the state. For 10 years, the atlas has continued to be a crucial tool for those involved in mining as well as individuals involved with mining accidents or the potential resulting mine subsidence, where the ground surface shifts.

The incident that spurred the creation of the Pennsylvania Mine Map Atlas took place 11 years beforehand. In July 2002, in the Quecreek Mine in Somerset County, miners accidentally breached the wall of an adjacent abandoned, flooded mine. This caused an estimated 150 million gallons of water to burst into Quecreek Mine, trapping nine miners 250 feet underground for 77 hours. Rescuers worked for days to determine where the miners were located and to drill into the mine to extract all nine miners safely, which they ultimately did on July 28.

According to the investigation conducted by the Mine Safety and Health Administration, the primary cause of the accident was the use of an undated and uncertified mine map. The lack of accurate map information also challenged rescuers who struggled to identify exactly how deep underground the miners were and what location above ground corresponded with where the miners were located underground.  

David Hess, the secretary of the Pennsylvania Department of Environmental Protection in 2002, said in an interview in The New York Times that it was a ''one in a million shot'' that the rescuers successfully sunk an air pipe to the trapped miners. He said that “the placement of the pipe was a matter of informed guesswork by mining engineers poring over maps.”  

Soon after the accident at Quecreek, PASDA was approached by the PA DEP.    

“We met with a number of PA DEP staff to discuss what the possibilities were for providing access to underground mine maps,” said Maurie Kelly, PASDA director. “The primary driver behind the effort at the time was to make sure that if there was another accident, information would be quickly and widely available to everyone involved in dealing with it.”  

The other key driver in creating the Pennsylvania Mine Map Atlas was to address the issue of mine subsidence and its impact on property owners throughout the state, according to Kelly.  

“Mine subsidence is when a mine collapses and whatever sits on top of it falls into the hole that the mine created or the area starts to subside and you start to experience structural damages,” Kelly said.  

Pennsylvania is criss-crossed with underground mines, most of which are in the western part of the state. In 2020, the PA DEP reported that there were over 40 active underground coal mines and 5,000 or more abandoned underground mines in Pennsylvania. The PA DEP also estimates that millions of structures in Pennsylvania are located over old, abandoned underground coal and clay mines. 

Until the Pennsylvania Mine Map Atlas, maps were not formally cataloged. They were a disorderly and dispersed anthology of mine history scattered among private and public parties.  

“Some maps were kept at PA DEP as well as mining companies, some at local government offices, some at academic institutions and even some in people's attics,” Kelly said. “Remember, the underground mines in Pennsylvania go back into the 1800s, so, in some cases, the actual physical maps themselves were older.”  

The effort to gather the maps was a challenging task for the PA DEP, according to Kelly, and it involved multiple stakeholders, colleges and non-profits.   

“We did a lot of brainstorming and came up with ideas about how it would work,” she said. “The technology was not quite where it needed to be to develop what we wanted at that time. But the real first step was getting the actual mine maps.”  

According to Kelly, PA DEP staff put in countless hours over multiple years to develop a plan for the mine atlas and the PA DEP database known as the Pennsylvania Historic Underground Mine Map Inventory System (PHUMMIS).  

“The Pennsylvania Mine Map Atlas is directly linked to information in PHUMMIS and vice versa,” Kelly said. “Together these two resources provide an enormous amount of information on Pennsylvania’s underground mines.”  

Today, PASDA, which is a part of the Institutes of Energy and the Environment, works directly with the staff at PA DEP Bureau of Mining Programs, specifically with the staff at the PA DEP California District Mining Office to acquire and provide access to the data as well as respond to inquiries.  

“The individuals at the Bureau of Mining and the California District Mining Office are amazing,” Kelly said. “Their knowledge of mining and mining history is incredible. They are always there to help our users and to find new ways for PA DEP to utilize the data. It is really an incredibly dedicated group of people.”  

Kelly said the use of the atlas has grown over the years.   

“Property owners, surveyors, developers, researchers and government agencies all use the atlas,” Kelly said. “In 2022, there were about 6 million uses of the atlas. We also are serving out streaming data services that can be pulled into software on users' desktops, laptops or phones without having to download data. That allows individuals in the field to pull in the mine maps to their devices quickly and easily. Many mining engineering programs use the atlas for teaching and student projects, including Penn State’s mining program.”