Welcome

   The Cedar Key Historical Society (CKHS) was awarded a Grant by the Department of State, Division of Historical Resources and the State of Florida, commencing July 1, 2021. The Cedar Key Cemetery project scope of work was contracted by Digital Heritage Interactive LLC. ( see procurement process to left) 

    The purpose of this grant project in short was;  to conduct a full mapping of marked graves, complete inventory, ground penetrating radar (GPR) survey of several areas likely associated with unmarked burials, identify marked African American burials in the cemetery, create an interactive  (GIS) Map, produce a survey report and update the Florida Master Site File. This project uses an interdisciplinary approach combining field mapping, GPR survey, and documentary research to produce an accurate map for use by the City of Cedar Key to manage the cemetery’s burials. In addition, this project equally focuses on identifying marked African American burials, locating  all unmarked graves as possible.  

The results of this project includes an interactive map based on the field mapping of approximately 1,250 marked burials and other cemetery furniture (e.g., walls, benches) in the Cedar Key Cemetery. This interactive map and the GIS that informs it also includes the results of a GPR survey to identify subsurface anomalies.This project provides new historical information through a complete inventory of all marked burials (as of June 2022) as well as GPR survey of 18 grids containing approximately 90 unmarked burials. The grant contract deliverables include an interactive GIS map of the results of the mapping and GPR survey report and updated Florida Master Site File (FMSF) form for the cemetery and archival research resulted in a final archaeological survey report conforming to Chapter 1A-46, Florida Administrative Code.

 A central goal of this project centers on identifying African American marked burials in the cemetery. As such, photogrammetry documentation of 16 grave markers and historical research related to African American burials in the site was also conducted. Results demonstrate far more African American burials that previously thought, in additional areas and many of them clearly marked, and historical documentary research revealed 2 dozen marked African American burials in the eastern areas of the cemetery, most of which were not previously thought to be African American because of their location or the illegi

    The distribution of marked African American graves in the cemetery does not conform to typically segregated cemeteries in the rural South. Typically, if Black and White burials occur in the same location, they are spatially separated in a clear way.  Deliverables were submitted and accepted by the State of Florida on August 2022. 

REPORT SUMMARY

MORE DETAILED/TECHNICAL INFORMATION BELOW.

The outputs of this work include, not limited to :

• Report on the findings of the GPR Survey Mapping
•  GIS Files of all Findings, 
• Updated Florida Master Site File forms
• An interactive Map for the CKHS to host on their website.-. 

 The survey report  and GIS Files, Mapping are  secured are on a hard drive in the Archives of the Cedar Key Historical Society.

Updated Florida Master Sight File PDF Below 

Interactive map is on this website, click button below. 

Procurement Process:

•  The Grantee shall provide maximum open competition when procuring goods and services related to the grant-assisted project. Procurement documentation supporting leading open competition must be submitted to the Division for review and approval before the execution of project contracts. 
• The Grantee shall submit survey project contracts to the Division for review and approval before execution. Procurement documentation supporting maximum open competition must be submitted to the Division for review and approval before the execution of project contracts. 

Following state procurement guidelines, the proposal submitted by Digital Heritage Interactive LLC was accepted by the Cedar Key Historical Society Board of Directors and the Division of HIstoric Preservation and the State of Florida. 

Digital Heritage Interactive LLC 

Diana González-Tennant, MA, 

RPA Project Manager 

Edward González-Tennant, PhD, 

RPA GPR Specialist 

(DHI) Digital Heritage Interactive LLC has undertaken similar survey, GIS, GPR, and interactive mapping projects in Levy County and elsewhere. This includes Dr. Edward Gonzalez-Tennant's cemetery documentation work in  Rosewood and Shiloh cemeteries, funded by a Florida Small Matching Grant, and significant work directing similar projects elsewhere in the state. This work has resulted in approved reports submitted to the same state agency funding the current project. 

Credits:

• Cedar Key City Commission and City Staff expressed their strong and unanimous backing to the cause championed by the Cedar Key Historical Society, bolstered further by a widespread show of public support from both those residing in the city and its extended community.
• The Cedar Key Historical Society Board of Directors, members, and sponsors strongly endorsed this project to preserve and promote the reminiscences of this historic city. 
• Historic Preservation Grants -  Florida Department of State Division of Historical Resources 

This investigation was conducted to comply with Section 106 of the National Historic Preservation Act (as amended) and its implementing regulation 36 CFR 800 (Protection of Historic Properties). All work performed is consistent with the FDHR recommendations for such projects as stipulated in the FDHR's Cultural Resource Management Standards & Operations Manual, Module Three: Guidelines for Use by Historic Preservation Professionals. This study complies with Chapter 267 of the Florida Statutes and Rule Chapter 1A‐46, Florida Administration Code. This project also adheres to Chapter 872 of the 2015 Florida Statutes, which protects all memorials, grave ornaments, and burial enclosures from destruction and removal. These statutes extend to unmarked burials as well. Chapter 3 includes procedures for dealing with unexpected discoveries. No graves were disturbed for this project.

The Cedar Key Historical Society Board of Directors and the Executive Director did not receive any financial compensation from this grant.

    GPR is a geophysical method offering a non‐invasive option for archaeological surveys. GPR uses electromagnetic waves generated from an antenna – pushed along the ground – from which reflective signals are collected, processed, and interpreted. The theory of operation and applications for GPR in archaeology are well-known, having been synthesized by Conyers (2004, 2006a, 2006b) and Goodman et al. (2009). In brief, a GPR unit records reflected radar energy. It uses a lapse in travel time and varying amplitude to create 2D transects, commonly referred to as radargrams or reflection profiles. Profiles can be compiled to create 2‐D and 3‐D imagery (Goodman et al. 2009). Data is collected in linear transects arranged in a grid. Typically, GPR surveys are oriented perpendicular to the objects they hope to detect. In the case of graves, which generally are oriented east-west, transects are arranged north-south, perpendicular to the potential objects. Marked burials in the Cedar Key Cemetery were roughly oriented in this manner. However, considerable variety did exist, with many graves being oriented up to 45 degrees off an accurate east-west line. A series of grids oriented north-south were created, and transects were spaced .5m apart, allowing for several hits or returns per buried anomaly/feature. As historic graves typically span 1-2 meters, they will appear in 4-6 transects.

Ground Penetrating Radar Equipment

The GPR equipment used for this project was a 500MHz antenna mounted on a four-wheel cart. Recent GPR testing in Florida suggests frequencies between 250MHz and 500MHz are ideal for locating unmarked historical burials (Schultz and Martin 2011). However, most archaeologists prefer the 400MHz - 500MHz range because it offers a superior resolution for identifying subsurface anomalies likely to be historic burials. A four-wheel cart marked distance in the data.

GPR DATA Collection and Process:

 Typically post, processed, and the transects are analyzed to identify potential anomalies that may be unmarked burials. In essence, hyperbolas in each transect are noted and tracked across neighboring hyperbolas. These features are referred to as anomalies, which are identified as potential unmarked burials if they meet several aspects. This project used four characteristics to determine if an anomaly is likely to be an unmarked burial. A four-part classification scheme was adopted for this project, and anomalies considered potential candidates to be unmarked burials if they met one or more of the following: crosses multiple transects (2-3+), roughly oriented east-west, rectangular/appearance, and other additional aspects (e.g., grave marker present). Potential graves were given confidence values of 1 - 3, with 1 being the highest confidence and meeting three or more of the above characteristics. A confidence value of 2 means at least two characteristics are met, and a value of 1 means only one was met.  

The GPR data for this project was recorded in the .dzt format, and post-processing was completed with GSSI’s Radan software, which natively works with the .dzt data format. Radan was used to filter the field data and construct horizontal slices interpolated from individual transects (aka radargrams). Transects for each grid were grouped and batch processed. Although individual settings differed, each transect was time zeroed, filtered, migrated, and varying degrees of gain applied. The Time Zero processing step aligns the subsurface data with the earth’s surface. Findings: A careful examination of 450 transects across 18 grids revealed 90 anomalies. Digital Heritage Interactive LLC. 

  For this project, FIR or IIR filters were applied, and the decision was made with each batch of files based on which set of filters best-removed noise from the transects. FIR is an older filter set meant to remove noise and horizontal banding. IIR is a newer filter type that is less resource intensive and focuses on eliminating noise. In practice, these filters remove signals above and below a specified set of frequencies. These can remove or lessen interference from subsurface metallic objects, cellular phone interference (4G uses 750-900MHz range), and so forth. In practice, most transects for this project had Low Pass set to 750MHz and High Pass between 125 and 250MHZ. If FIR filtering was used, a boxcar background removal filter was also applied, typically with a length range of 21-41. If IIR filters were used, the Radan Background Removal filter was also involved (which effectively mirrors the Noise Band Removal filter). Ranges were adjusted to equalize data vertically, making deeper anomalies more visible.

 Cemetery Mapping and Interactive Map    

    Marked burials were mapped using a combination of total station and RTK GNSS receiver. Features mapped include headstones, footstones, slabs, and areas where the shell has been deposited to mark/outline graves. In addition, features not associated with specific burials were also mapped, including walls, benches, and similar features typically placed alongside family plots. All parts were organized as a series of shapefiles in QGIS. Information from legible markers was added to the attribute table of relevant GIS features. Users of the GIS and interactive map can locate every visible part present as of mid-June 2022. Users simply choose the Identify tool and click on features to access this information. In addition, when available, a hyperlink to the grave’s Find A Grave page is also included in the attribute table. 

The Interactive Map mirrored the appearance of the GIS map document and was created using the QGIS 2 Web plugin. This freely available plugin converts a QGIS map document into a set of standalone files that can be uploaded to the most popular web hosting platforms and then intuitively accessed in a web browser. The interactive map for this project is provided as a zip archive/file that can be copied to any folder on a user’s computer and accessed by clicking the index.html file. DHI has previously provided similar interactive mapping content to the Cedar Key Historical Society. The interactive map allows the historical society, the City of Cedar Key, and members of the public to access an up-to-date map of the entire cemetery. This also includes the results of the GPR survey. 

 TIMELINE:

Fieldwork took place over eight weeks between December 2021 and June 2022. The first week in December 2021 consisted of a site visit, which included surveying possible GPR areas with CKHS staff and establishing a preliminary mapping grid. 

Two additional weeks of mapping took place in March 2022. They consisted of mapping several sections of the cemetery using the dual channel, real-time kinematic (RTK) global navigation satellite system (GNSS) receivers. The additional mapping occurred during two other visits, including one week in April and four weeks in late May through mid-June. 

The GPR survey was conducted during the final four weeks, following the clearance of areas considered to have a high likelihood of containing unmarked graves, which the city of Cedar Key facilities department completed in late May 2022. Historical research and report preparation occurred primarily in June and July 2022.