A BREATH OF LIFE TO THE DEAD: APPLICATIONS OF THREE-DIMENSIONAL IMPULSE GROUND PENETRATING RADAR FOR THE DELINEATION OF LATE 19TH – EARLY 20TH CENTURY UNMARKED GRAVES IN MILTON, PA

Ground penetrating radar (GPR) has been successfully utilized to map stratigraphic horizons, structures and discrete objects such as utilities within the sub-surface. Increasingly, GPR studies have attempted to use GPR for the delineation of clandestine graves. However, a potentially overlooked application is the delineation of lost, misplaced or unmarked grave sites in cemeteries. In this study detailed three-dimensional GPR was utilized to evaluate its effectiveness at resolving suspected burial plots interred between 1854 -1925 at two locations in Milton, PA. Located within the valley and ridge province of central Pennsylvania, the geology consists of 0.5 - 3 m thick loamy ultisol soils overlying the Silurian age Bloomsburg Formation. The first study site is a 10 m by 33.5 m area in the southwest corner of Harmony Cemetery where deceased are believed to be reinterred from their original location due to a flood in 1889. Site two is a 13 m by 20 m area located in the south east corner of Milton Cemetery described as a "potter's field" with a relatively unknown history of burials and burial practices. GPR was utilized as a non-invasive attempt to distinguish disturbances in the soil at both sites indicative of human burial practices of the era. A GSSI SIR-2000 with a 400 MHz antenna was used to collect 96 transects at one foot intervals at both sites. Bistatic WARR (CMP) array with 100 MHz antennae were employed to calculate a dielectric constant and constrain depth estimates. Numerous control lines were also used in order to compare amplitude and signal characteristics of known burial plots and practices to survey results obtained at both sites.. Radan 6.5 was used to process data and enhance interpretation based on two dimensional transects and three dimensional modeling. Processed results suggest there may be few, if any, unmarked graves at the Harmony Cemetery site. However, the Milton Cemetery site contains numerous anomalies indicating the presence of as many as 15 unmarked human burials.