PROFESSIONAL SERVICES DESCRIPTION FOR THE POSITION OF: Paulsboro Marine Terminal Phase I Underwater Archeological Survey SUBMISSION DEADLINE: July 9, 2010 at 1:00 P.M. FAIR AND OPEN PUBLIC SOLICITATION PROCESS FOR PROFESSIONAL SERVICES FOR GLOUCESTER COUNTY IMPROVEMENT AUTHORITY 109 BUDD BOULEVARD WOODBURY, NEW JERSEY 08096 1 | Page Technical Report, Obstruction Survey for Future Activites at the Port of Paulsboro Gloucester County, New Jersey SPONSOR Gloucester County Improvement Authority 254 County House Road Clarksboro, NJ 08020 DRAFT SURVEY COMPANY Aqua Survey Inc. 469 Point Breeze Rd. Flemington, NJ 08822 ASI Project Number 29-132 October 15, 2009 Technical Report, Obstruction Survey for Future Activites at the Port of Paulsboro Gloucester County, New Jersey SPONSOR Gloucester County Improvement Authority 254 County House Road Clarksboro, NJ 08020 ASI Project Number 29-132 DRAFT This report, as well as all records and raw data were audited and found to be an accurate reflection of the study. Copies of raw data will be maintained by Aqua Survey, Inc., 469 Point Breeze Road, Flemington, NJ 08822. Kenneth Hayes Date President Mark Padover Date Lead Field Scientist Table of Contents I. EXECUTIVE SUMMARY ................................................................................................ 1 II. MATERIALS, METHODS, AND RESULTS ................................................................... 4 A. Project Area ........................................................................................................................ 4 B. Horizontal Positioning ........................................................................................................ 4 C. Magnetometer Data Collection and Results in Northern Area ........................................... 6 D. Side Scan Sonar Survey Data Collection and Results ........................................................ 9 E. Sub-Bottom Profiler Survey ............................................................................................. 13 III. PROJECT CONCLUSIONS ............................................................................................. 15 Appendices Appendix A. Equipment Data Sheets List of Figures Figure 1 Map showing area surveyed in blue (NOAA chart 12312). ....................................... 5 Figure 2 Magnetometer targets in Mantua Creek and the Cove ................................................ 8 Figure 3 Overall magnetometer map and target Mag 6 ............................................................. 8 Figure 4 Side scan mosaic of the mouth of Mantua Creek. .................................................... 10 Figure 5 Side scan mosaic close-up showing large logs/trees. ................................................ 11 Figure 6 Side scan mosaic close-up showing debris off of pier. ............................................. 12 Figure 7 Sample of sub-bottom image showing subsurface reflectors. .................................. 14 List of Tables Table 1 Table of Magnetic Anomalies ……………………….………………………… 6 I. EXECUTIVE SUMMARY A geophysical remote sensing obstruction and debris survey was conducted covering the area where future activities are to be conducted in the mouth of Mantua Creek and along the eastern shoreline of the Delaware River for the Port of Paulsboro in Gloucester County, New Jersey. The area within Mantua Creek that was surveyed extended from shoreline to shoreline and 825 feet upstream from the end of the southern jetty protecting its entrance into the Delaware River. The area of the Delaware River that was surveyed included an area extending approximately 3,150 feet downstream from the end of the north jetty of Mantua Creek and extending from nearly the shoreline to a distance of approximately 625 feet into the river from the existing pier structures. The areas surveyed encompassed the entire area where future dredging activities may occur. The primary goal of the geophysical survey was to detect the presence of exposed and buried debris and submerged utilities and to identify any anomalies as accurately as possible that could be impacted by future activities. The geophysical survey conducted on October 26, 2009. Technologies and techniques employed included side scan sonar, magnetometer, sub-bottom profiler, and differential global positioning (DGPS). Survey lines spaced 50 feet apart were run parallel to the shoreline using the side scan sonar, magnetometer, and sub-bottom profiler. The survey methodology was designed to provide data indicating the position and relative size of exposed targets in the survey area, as well as archaeological data essential for complying with the National Historic Preservation Act of 1966, as amended, through 1992 (36 CFR 800, Protection of Historic Properties) and the Abandoned Shipwreck Act of 1987 (Abandoned Shipwreck Act Guidelines, National Park Service, Federal Register, Vol. 55, No. 3, December 4, 1990, pages 50116-50145). All operations were conducted using DGPS with a horizontal accuracy of less than 3 feet. During the survey, the horizontal dilution of precision (HDOP) of the DGPS data was monitored. If the HDOP exceeded 2.0, survey activities were suspended or data was not used. The DGPS antenna was mounted directly over side scan sonar and sub-bottom profiler to eliminate offset errors and ensure positions tied directly with the collected data. The magnetometer was towed at a measured fixed distance behind the vessel. Hypack 2009 was used for magnetometer data collection and very accurately models the towfish position based on tow cable length, a catenary factor, and vessel DGPS data. The magnetic survey was conducted using a Geometrics G-882 marine cesium magnetometer system. The primary objective was to detect exposed and buried debris within the survey area. During the survey, the sensor was towed behind the vessel from the nose tow point to get the sensor as close to the bottom as was safe in the shallow water. The survey area included existing pier steel structures as 1 well as shoreline debris. These features can obscure the magnetic signature of smaller debris if the small debris is in close proximity to the larger structures. The large steel pier in the Delaware River was detectable by the magnetometer from more than 400 feet away and could easily have masked smaller debris located within a 250 foot radius. Six localized targets were detected during the survey. Targets Mag 1 through Mag 5 are located in or near the cove area in the Delaware River just east of the mouth of Mantua Creek. Target Mag 6 is located in deeper water in the Delaware River near the northwestern end of the survey area. A known sewer outfall was detected. The depth of burial of the outfall is not known. Target Mag 1 is a large anomaly located just to the east of the end on the sewer outfall. Targets Mag 2 and Mag 3 are located approximately 60 to 80 feet east of the sewer outfall. Target Mag 4 is located approximately 140 feet west of the sewer outfall. The short duration of these three anomalies indicates they are likely to be located near the sediment surface. Target Mag 5 is a complex collection of magnetic anomalies which was detected on five survey lines. The nature of the material generating the anomalies which make up Mag 5 and Mag 6 could not be determined from the surveys conducted. None of the magnetic anomalies were associated with targets in the side scan sonar records, indicating that all of the material generating the anomalies lies buried below the river sediment. An Edgetech 4100-FS dual frequency 100kHz/500kHz side scan sonar system was used for this survey. Range scale was set to 50 meters, which resulted in greater than 300 percent insonification of the river bed. Following the survey, the individual records were analyzed to detect any large objects or man-made targets that might be present. The sonar records were mosaiced using Chesapeake Technologies Sonar Wiz Map 4.0 software to provide a better overall view of the survey area and to produce a single geo-referenced image of the survey area. When analyzing the side scan mosaic, areas of submerged vegetation can be seen in the shallow waters along the southern shoreline within Mantua Creek and in the shallow water of the Delaware River. The remains of what appears to be a small dock measuring approximately 100 feet by 25 feet can be seen along the southern shoreline of Mantua Creek approximately 530 feet upstream of the end of the southern jetty. Small scattered objects can be seen within the channel of Mantua Creek. What appears to be two large logs/trees can be seen in the Delaware River, one in shallow water and one in deeper water off of the eastern end of the existing pier structures. Other scattered debris can be seen in the Delaware River within approximately 40 feet of the existing pier structures. None of the side scan sonar targets have signatures which appear to be indicative of submerged cultural resources. An ODEC Stratabox sonar system was used to collect the sub-bottom profiling data during the survey. The principal objective of the survey was to collect sub- bottom images to detect the presence of utility crossings of the river that may be 2 impacted by future vibracoring operations. During the survey, the transducer was hard-mounted to the side of the survey vessel with the navigational antenna mounted directly over the transducer, eliminating offset errors. The sensor was deployed at a depth of 3 feet to minimize interference from the vessel. The navigational data was logged