All data reduction procedures conform to those detailed in the DAPR.All sounding systems were calibrated as detailed in the DAPR.Side Scan Sonar (SSS) Coverage Analysis: For all details regarding SSS data processing, see the DAPR. Leidos chose to adhere to the coverage requirements in the Project Instructions using Complete Coverage, Option B (100% side scan sonar coverage with concurrent multibeam). The HSSD stated that 100% SSS coverage was insufficient to disprove a charted feature. Therefore, 100% SSS coverage was collected and verified for the entire survey area, and an additional 100% SSS coverage was collected over CSF assigned objects and charted objects that were not found, to verify disproval. Leidos generated two separate coverage mosaics at one-meter cell size resolution as specified in Section 8.2.1 of the HSSD. The first 100% and second 100% disproval coverage mosaics were independently reviewed using tools in SABER to verify data quality and swath coverage. The SABER Gapchecker routine was used to flag data gaps within each of the 100% SSS coverage mosaics. Additionally, the entirety of each SSS surface was visually scanned for holidays at various points during the data processing effort. Additional survey lines were run to fill any holidays that were detected. Both coverage mosaics are determined to be complete and sufficient to meet the requirements contained within the Project Instructions and HSSD. The mosaics are delivered as single georeferenced raster files for each 100 percent coverage, as floating point GeoTIFF format as specified in Sections 8.2.1 and 8.3.3 in the HSSD. Multibeam Echo Sounder Seafloor Backscatter: In accordance with the HSSD Section 6.2, Leidos collected MBES backscatter with all GSF data acquired. The MBES settings used were checked to ensure acceptable quality standards were met and to mitigate acoustic saturation of the backscatter data. The MBES backscatter data acquired were written to the GSF in real-time by ISS-2000 and are delivered in the final GSF files for this sheet. Per HSSD Section 6.2.1, as the Project Instructions did not state to evaluate the backscatter data; backscatter data were not processed by Leidos and no additional products were produced.file:///Q:/Survey/H13213_K371_KR_19/AHB_H13213/01_SAR/Reports/Survey/Descriptive_Report/Report/Office/SupportFiles/H13213_Figure_6.jpgSummary of Crossing AnalysisRefer to Separates II for details about how the crossing analyses were performed and a complete discussion of each analysis and tabular results. Figure 6 summarizes the crossline comparison results.Sonar system quality control checks were conducted as detailed in the DAPR.file:///Q:/Survey/H13213_K371_KR_19/AHB_H13213/01_SAR/Reports/Survey/Descriptive_Report/Report/Office/SupportFiles/H13213_Figure_8.jpgSuspended Sediment Water Transition to “Clean” Water in Side Scan Sonar RecordTurbidity ImpactsH13213 survey area was located just west of the Sabine Pass entrance. As a result, H13213 survey occasionally experienced zones of increased suspended sediments in discrete water masses during local weather events. Interactions could be seen in the side scan sonar record as an increase in the signal returns. At the interface boundaries of suspended sediments and “clear” water, the transition was seen in the side scan record as a discrete tide line (Figure 8) and was noted within the Side Scan Review Log (Separates I). In all cases, if the increased signal return of the side scan sonar inhibited the ability to discern a 1x1x1-meter object, the data were reacquired.All equipment and survey methods are detailed in the DAPR.Multibeam Coverage AnalysisLeidos chose to achieve the coverage requirement using 100% side scan sonar coverage with concurrent multibeam bathymetry. To achieve this coverage, the M/V Atlantic Surveyor used a towed Klein 3000 SSS set to 25-meter or 50-meter range scales. Mainscheme line spacing was 40 meters and 80 meters respectively, which ensured 100% SSS coverage. The HSSD stated that 100% SSS coverage was insufficient to disprove a charted feature. Therefore, Leidos reviewed the Composite Source File (CSF), BSB charts, and ENC charts and completed an additional 100% SSS coverage, and resulting MBES coverage over charted and assigned objects not found during survey in order to verify disproval in accordance with Section 7.3.4 in the HSSD. A disproval search radius was developed as specified in the Project Reference File (PRF), Final_OPR-K371-KR-19_PRF.000 provided on 18 March 2019 or following best practices if not specified and is documented within the H13213 S-57 FFF. For all charted objects within the assigned H13213 Statement of Work (SOW), each object’s disproval data covered an area of at least the assigned disproval search radius. The SABER Gapchecker program was used to flag MBES data gaps within the CUBE surface. Additionally, the entire surface was visually scanned for holidays at various points during the data processing effort. Additional survey lines were run to fill any holidays that were detected. A final review of the CUBE Depth surface of the H13213 one-meter PFM showed that there were no holidays as defined for complete coverage surveys in Section 5.2.2.3 of the HSSD. The final H13213 CUBE PFM was examined for the number of soundings contributing to the chosen CUBE hypotheses for each node by running SABER’s Frequency Distribution Tool on the Hypothesis Number of Soundings (Hyp. # Soundings) surface. The Hyp. # Soundings surface reports the number of soundings that were used to compute the chosen hypothesis. Analysis of the H13213 Hyp. # Soundings surface of the final H13213 one-meter PFM, revealed that 99.40% of all nodes contained five or more soundings; satisfying the requirements for complete coverage surveys, Option B, as specified in Section 5.2.2.3 of the HSSD.file:///Q:/Survey/H13213_K371_KR_19/AHB_H13213/01_SAR/Reports/Survey/Descriptive_Report/Report/Office/SupportFiles/H13213_Figure_9.jpgResidual Ten Centimeter Artifact Resulting From Suspended Sediments Shown at 50 Times Exaggeration for Illustration PurposesTurbidity ImpactsH13213 survey area was located just west of the Sabine Pass entrance. As a result, H13213 survey occasionally experienced zones of increased suspended sediments in discrete water masses during local weather events. As discussed these zones were seen in the side scan record and additionally was seen within the multibeam sonar data as a slight scattering of the bottom returns at the sediment water interface. When present, it resulted in a residual depth variation of approximately 10 centimeters, which was within the vertical uncertainty for the water depths (Figure 9).H1183210000EC&C2008H11832 junctions with H13213 to the east; 100.00% of the comparisons agreed within ±0.511 meters, within the calculated maximum allowable TVU of 0.52 meters.H1083620000SFugro Pelagos, Inc.1998H10836 junctions with H13213 to the south; 93.72% of the comparisons agreed within ±0.53 meters, the calculated maximum allowable TVU.H1085120000EC&C1998H10851 junctions with H13213 to the east; 86.55% of the comparisons agreed within ±0.53 meters, the calculated maximum allowable TVU.file:///Q:/Survey/H13213_K371_KR_19/AHB_H13213/01_SAR/Reports/Survey/Descriptive_Report/Report/Office/SupportFiles/H13213_Figure_7.jpgGeneral Locality of H13213 with Junctioning SurveysAs requested in the Project Instructions, analyses of the H13213 junctions with adjacent surveys were performed. There were three assigned prior surveys provided by NOAA under OPR-K371-KR-19 that junction H13213. Figure 7 shows the general locality of H13213 as it relates to the sheets to which junctions were performed. Details for each survey are listed in Table 7. Note that analysis of the junctions with sheet H13214 was not conducted, as processing efforts for that sheet were still ongoing. Refer to Separates II for details about how the junction analyses were performed and a complete discussion of each analysis and tabular results.On the M/V Atlantic Surveyor, the MVP30 was used to collect sound speed profile (SSP) data, refer to the DAPR for additional details. SSP data were obtained at intervals frequent enough to meet depth accuracy requirements. Section 5.2.3.3 of the HSSD requires that if the sound speed measured at the sonar head differs by more than two meters/second from the commensurate profile data, then another cast shall be acquired. There were times when the sound speed values exceeded the two meters/second threshold due to the local temporal and tidal variability. During these times, several profiles were acquired and reapplied in an effort to reduce these effects. The product of this effort resulted in the final data bearing no significant artifacts due to sound speed differences. All sound speed profiles applied for online bathymetry data collection were acquired within 500 meters of the bounds of the survey area as specified in Section 5.2.3.3 of the HSSD. Confidence checks of the sound speed profile casts were conducted by comparing at least two consecutive casts taken with different SSP sensors. Six sound speed confidence checks were conducted during H13213 and the results can be found in Separates II within the “Comparison Cast Log” section. All individual SSP files are delivered with the H13213 data and are broken out into sub-folders, which correspond to the purpose of each cast. Also, all individual SSP files for H13213 have been concatenated into four separate files based on the purpose of the cast, provided in CARIS format files (.svp), and delivered under (H13213/Processed/SVP/CARIS_SSP) on the delivery drive. In addition, sound speed data for the entire OPR-K371-KR-19 project will be submitted to NCEI following the NetCDF template format as specified in Section 8.3.6 of the HSSD.0.00ERS via VDATUM0.122N/A1.01.0N/AM/V Atlantic SurveyorFor specific details on the use and application of the SABER Total Propagated Uncertainty (TPU) model, refer to the DAPR. Once the TPU model was applied to the GSF bathymetry data, each beam was attributed with the horizontal uncertainty and the vertical uncertainty at the 95% confidence level. The vertical and horizontal uncertainty values, estimated by the TPU model for individual multibeam soundings, varied little across the dataset, tending to be most affected by beam angle. Individual soundings that had vertical and horizontal uncertainty values above IHO S-44 5th Edition, Order 1a were flagged as invalid during the uncertainty attribution. As discussed in the DAPR, SABER generates two vertical uncertainty surfaces; the Hypothesis Standard Deviation (Hyp. StdDev) and the Hypothesis Average Total Propagated Uncertainty (Hyp. AvgTPU). A third vertical uncertainty surface is generated from the larger value of these two uncertainties at each node and is referred to as the Hypothesis Final Uncertainty (Hyp. Final Uncertainty). The final H13213 one-meter PFM CUBE surface contained final vertical uncertainties that ranged from 0.260 meters to 0.586 meters. The IHO Order 1a maximum allowable vertical uncertainty was calculated to range between 0.504 to 0.527 meters, based on the minimum CUBE depth (4.961 meters) and maximum CUBE depth (12.902 meters). Results from the SABER Check PFM Uncertainty function identified that there was one node in the final H13213 one-meter PFM CUBE surface with final vertical uncertainties that exceeded IHO Order 1a allowable vertical uncertainty. This node was associated with a discrete object. The SABER Frequency Distribution Tool was also used to review the Hyp. Final Uncertainty surface within the final H13213 one-meter PFM grid, and the results showed that in the final one-meter PFM grid, 99.99% of all nodes had final uncertainties less than or equal to 0.510 meters. There was one node that exceeded 0.510 meters; which was associated with a discrete object.9110M/V Atlantic Surveyorfile:///Q:/Survey/H13213_K371_KR_19/AHB_H13213/01_SAR/Reports/Survey/Descriptive_Report/Report/Office/SupportFiles/H13213_Figure_5.jpgM/V Atlantic SurveyorThe M/V Atlantic Surveyor (Figure 5) was used to collect multibeam echo sounder (MBES) (RESON SeaBat T50), side scan sonar (SSS) (Klein 3000), and sound speed data during twenty-four hours per day survey operations. A detailed description of the vessel used is included in the DAPR.Leidos used their ISS-2000 software on a Windows 7 platform to acquire these survey data. Survey planning and data analysis were conducted using the Leidos SABER software on Red Hat Enterprise 6 Linux platforms. Klein 3000 side scan sonar (SSS) data were collected on a Windows 7 platform using Klein’s SonarPro software. Subsequent processing and review of the SSS data, including the generation of coverage mosaics, were accomplished using SABER. A detailed description of the systems and vessel used to acquire and process these data is included in the Data Acquisition and Processing Report (DAPR) for OPR-K371-KR-19, delivered concurrently with the Descriptive Report for H13213. There were no variations from the equipment configuration described in the DAPR.MBESTeledyne RESONSeaBat T50-RSSSKlein Marine SystemsEM 3000Positioning and Attitude SystemApplanixPOS MV 320 v5Sound Speed SystemAML OceanographicMVP30Sound Speed SystemAML OceanographicMicroX SVA detailed description of the equipment installed is included in the DAPR.NOAA Extended Attribute File V5-45.4.0.22.3SABERLeidos5.4.0.22.3SABERLeidosThe primary data processing software used for both bathymetry and imagery was SABER. There were no software configuration changes after the DAPR was submitted.1Complete Coverage, Option B (100% side scan sonar coverage with concurrent multibeam)BAG8.01412.902H13213_MB_1m_MLLW_Final_1_of_2N/A1Complete Coverage, Option B (100% side scan sonar coverage with concurrent multibeam)BAG4.9619.914H13213_MB_1m_MLLW_Final_2_of_2N/A1100% SSSSSS Mosaic (.tif)0.000.00H13213_SSSAB_1m_100kHz_1of2N/A1Second 100% SSS For Object DisprovalSSS Mosaic (.tif)0.000.00H13213_SSSAB_1m_100kHz_2of2N/AFor the purposes of grid management, the Branch has created a single H13213_MB_1m_MLLW_1of1.bag that replaces the H13213_MB_1m_MLLW_Final-X_of_2 multibeam bathymetry grids submitted by the field unit. The H13213_MB_1m_MLLW_1of1.bag is the final deliverable to be used in charting products and for archive.Complete Coverage Section 5.2.2.3 of the HSSD requires one-meter node resolution for depths ranging from zero meters to 20 meters. Leidos generated CUBE PFM grids for H13213 at one-meter resolution. The CUBE Depth surface of the final H13213 one-meter PFM (containing all valid depth data) was used to assess and document multibeam survey coverage. SABER populates the CUBE depth with either the node’s chosen hypothesis or the depth of a feature or designated sounding set by the hydrographer, which overrides the chosen hypothesis. The range of CUBE depths of the H13213 one-meter PFM was from 4.961 meters (16.276 feet; 0.260 meters Total Vertical Uncertainty [TVU]) to 12.902 meters (42.329 feet; 0.260 meters TVU). The final gridded bathymetry data are delivered as a Bathymetric Attributed Grid (BAG). The BAG files were exported from the CUBE PFM grid as detailed in the DAPR.20000H132139 NM WSW of Texas PointTexas1United StatesBasic Hydrographic Survey2019-02-21meters2019Contract: EA-133C-14-CQ-0033/TO-0005. Contractor: Leidos, 221 Third Street, Newport, RI 02840 USA. Subcontractors: Divemasters, Inc., 15 Pumpshire Road, Toms River, NJ 08753; OARS, 8705 Shoal Creek Blvd, Suite 109, Austin, TX 78757. Leidos Doc. 19-TR-040. All times were recorded in UTC. Data were collected in North American Datum of 1983 (NAD83) 2011 realization 2010 (NAD83(2011)2010.0), UTM Zone 15N.Any revisions to the Descriptive Report (DR) applied during office processing are shown in red italic text. The DR is maintained as a field unit product, therefore all information and recommendations within this report are considered preliminary unless otherwise noted. The final disposition of survey data is represented in the NOAA nautical chart products. All pertinent records for this survey are archived at the National Centers for Environmental Information (NCEI) and can be retrieved via https://www.ncei.noaa.gov/. Products created during office processing were generated in NAD83 UTM 15N, MLLW. All references to other horizontal or vertical datums in this report are applicable to the processed hydrographic data provided by the field unit.Side Scan SonarMultibeam Echo Sounder BackscatterMultibeam Echo SounderPaul L. Donaldson2019-09-252019-04-24Atlantic Hydrographic BranchUTCOPR-K371-KR-19Port Arthur Traffic LanesPort Arthur, TexasSAICContractorfile:///Q:/Survey/H13213_K371_KR_19/AHB_H13213/01_SAR/Reports/Survey/Descriptive_Report/Report/Office/SupportFiles/H13213_Figure_1.jpgH13213 Survey Bounds93.952929.64523193.7988529.521693The area surveyed was a section of the Gulf of Mexico west southwest of Texas Point, TX (Figure 1).Complete Coverage (Refer to HSSD Section 5.2.2.3). Complete 6443 LNMs. Transit mileage and data which do not meet HSSD specifications shall not count towards the completion of the LNM. Notify the Project Manager/COR upon nearing completion. The final survey area shall be squared off and ensure the full investigation of any features within the surveyed extent. Project Manager/COR may adjust survey prioritization based on observed shoaling. Additional or fewer sheets may be assigned based on survey area achieved.All waters in survey areaLeidos chose to achieve the coverage requirement using Complete Coverage, Option B (100% side scan sonar coverage with concurrent multibeam). Survey coverage achieved was in accordance with the requirements in the Project Instructions and the HSSD (Figure 2 through Figure 4).The entire survey is adequate to supersede previous data.Leidos warrants only that the survey data acquired by Leidos and delivered to NOAA under Contract EA-133C-14-CQ-0033 reflects the state of the sea floor in existence on the day and at the time the survey was conducted. H13213 was surveyed in accordance with the following documents: 1. Project Instructions, OPR-K371-KR-19, dated 21 February 2019 2. Hydrographic Surveys Specifications and Deliverables (HSSD), March 2019 3. Waiver_2019 HSSD_signed.pdf, dated 05 November 2019 4. OPR-K371-KR-19 Statement of Work, dated 21 February 20192019-04-242019-04-252019-04-262019-04-272019-04-282019-04-292019-05-142019-08-012019-08-022019-08-032019-08-062019-08-072019-09-232019-09-242019-09-25330300037.560889.3600000M/V Atlantic Surveyor04.2237.560889.3600000file:///Q:/Survey/H13213_K371_KR_19/AHB_H13213/01_SAR/Reports/Survey/Descriptive_Report/Report/Office/SupportFiles/H13213_Figure_2.jpgFinal Bathymetry Coverage for H13213file:///Q:/Survey/H13213_K371_KR_19/AHB_H13213/01_SAR/Reports/Survey/Descriptive_Report/Report/Office/SupportFiles/H13213_Figure_3.jpgFinal Side Scan Coverage for H13213 (100% coverage)file:///Q:/Survey/H13213_K371_KR_19/AHB_H13213/01_SAR/Reports/Survey/Descriptive_Report/Report/Office/SupportFiles/H13213_Figure_4.jpgFinal Side Scan Coverage for H13213 (disproval coverage)Survey limits were acquired in accordance with the requirements in the Project Instructions and the Hydrographic Surveys Specifications and Deliverables (HSSD).The purpose of this survey is to provide contemporary surveys to update National Ocean Service (NOS) nautical charting products. Port Arthur, located on the Gulf of Mexico Intra-costal Waterway in Texas, is home to a large refinery network (1). The Port of Port Arthur hosts the Motiva refinery, the largest oil refinery in the United States (2). Traffic flow through the Port is heavy and in 2010, an oil spill occurred from an oil tanker and barge collision spilling 450,000 gallons of oil into the Sabine/Neches waterway (3). This busy seaport has also been hit by several hurricanes. On August 29, 2017, Hurricane Harvey hit Port Arthur bringing upwards of 40 inches of rainfall and widespread flooding to the area (4). This Hurricane had the potential to change the seafloor of the Port which sees over 35 million tons of vessel traffic (5). To continue to promote safe passage of traffic through the Port, this project will survey 286 square nautical miles (SNM) of seafloor in Port Arthur. The survey will address concerns of migrating shoals and exposed hazard by updating bathymetry and positions of hazards and reducing the risk to navigation. Survey data from this project is intended to supersede all prior survey data in the common area and will provide contemporary data to update National Ocean Service (NOS) nautical charting products. Citations 1.https://www.portarthurtx.gov/236/About-Us 2."Tropical Storm Harvey Closes America's Biggest Refinery". Maritime Executive. 30 August 2017. Retrieved 31 August 2017. 3. Gonzalez, Angel (24 January 2010). "Oil Spill Hits Texas Port". The Wall Street Journal. Retrieved 24 January 2010. 4. Harrington, Rebecca. "Flash floods send Texans into 'survival mode' as Harvey hits Port Arthur with 26 inches of rain in one day". BusinessInsider.com. Business Insider. Retrieved 30 August 2017. 5. The U.S. Waterway System, 2016 Transportation Facts & Information. Navigation and Civil Works Decision Support Center, U.S. Army Corps of Engineers.40000US5TX72M442019-11-04false2019-10-04file:///Q:/Survey/H13213_K371_KR_19/AHB_H13213/01_SAR/Reports/Survey/Descriptive_Report/Report/Office/SupportFiles/H13213_Figure_10.jpgENC US5TX72M Charted Soundings (red) with H13213 CUBE Depth Selected Soundings (black)file:///Q:/Survey/H13213_K371_KR_19/AHB_H13213/01_SAR/Reports/Survey/Descriptive_Report/Report/Office/SupportFiles/H13213_Figure_11.jpgENC US5TX72M Charted 3.6-Meter and 5.4-Meter Contours (red) with H13213 CUBE Depth Selected Soundings (black)ENC US5TX72M covers the H13213 survey area from 29° 36’ 00.77”N northward. CUBE depths within H13213 were generally deeper than charted depths across the survey area, with observed depths generally 1.5m to 2.0m deeper than the charted depths (Figure 10). Within the H13213 survey area, the observed 5.4-meter depths have migrated north beyond the currently charted 3.6-meter contour, as observed in Figure 11 which shows the charted 3.6-meter and 5.4-meter contours from ENC US5TX72M as compared to the final CUBE Depth selected soundings observed from the H13213 survey.80000US4TX71M372019-11-08false2019-11-08file:///Q:/Survey/H13213_K371_KR_19/AHB_H13213/01_SAR/Reports/Survey/Descriptive_Report/Report/Office/SupportFiles/H13213_Figure_12.jpgENC US4TX71M Charted Soundings (red) with H13213 CUBE Depth Selected Soundings (black)file:///Q:/Survey/H13213_K371_KR_19/AHB_H13213/01_SAR/Reports/Survey/Descriptive_Report/Report/Office/SupportFiles/H13213_Figure_13.jpgENC US4TX71M Charted 5.4-Meter and 9.1-Meter Contours (red) with H13213 CUBE Depth Selected Soundings (black)ENC US4TX71M covers the H13213 survey area from 29° 36’ 00.77”N southward. CUBE depths within H13213 were generally deeper than charted depths in the northern areas but agreed in the southern portion of the survey area (Figure 12). Within the H13213 survey area, the observed 5.4-meter depths have migrated north beyond the currently charted 5.4-meter contour, however, the charted 9.1-meter depth contour is generally in good agreement with observed depths except in the eastern edge of the survey coverage (Figure 13).file:///Q:/Survey/H13213_K371_KR_19/AHB_H13213/01_SAR/Reports/Survey/Descriptive_Report/Report/Office/SupportFiles/H13213_Figure_14.jpgSabine Pass Entrance Illustrating the East Jetty (Background) and the West Jetty (Foreground)file:///Q:/Survey/H13213_K371_KR_19/AHB_H13213/01_SAR/Reports/Survey/Descriptive_Report/Report/Office/SupportFiles/H13213_Figure_15.jpgSabine Pass West Jetty (Black Line) Charted as Always Dry on ENC US5TX72MThere were four charted features which were assigned in the final CSF, Final_OPR-K371-KR-19_CSF.000, within the SOW of H13213. See the H13213 S-57 FFF for all the details and recommendations regarding these features. There was one charted pile and one charted wreck on ENC US5TX72M. Search area with radii of at least 80 meters and 470 meters respectively was covered with 200% SSS and MBES. No features were found within the data covering the extents of either search radius. The two remaining assigned features were charted on ENC US4TX71M. These two wrecks, charted as dangerous always under water/submerged, were covered with 200% SSS and 100% MBES over an area with a radius of at least 470 meters. No features were found within the data covering the extents of either search radius. During survey operations, Leidos observed that the western jetty of the Sabine Pass entrance was submerged or mostly submerged for much of its length while the eastern jetty of the Sabine Pass entrance was observed above the water line (Figure 14). Observations were made near a high tide on JD 267. These jetties both fall outside the assigned H13213 SOW and due to safety concerns were not investigated further by Leidos. The Sabine Pass west jetty is charted on ENC US5TX72M as a shoreline construction object, category of pier as jetty, and attributed water level of always dry (Figure 15).No Maritime Boundary Points were assigned for this survey.In accordance with both the Project Instructions and Section 7.2.3 of the HSSD, bottom characteristics were obtained for H13213. Bottom characteristics were acquired at the three locations assigned in the PRF by NOAA. Leidos did not modify the bottom sample locations from the location proposed by NOAA in the PRF. Bottom characteristics collected during H13213 are included in the H13213 S-57 FFF, named H13213_FFF.000, within the Seabed Area (SBDARE) object, and are classified according to the requirements set forth in the HSSD. In addition, images of the sediment obtained for each bottom sample are referenced in the H13213_FFF.000 and are included on the delivery drive under the folder H13213/Processed/Multimedia.There were no channels within the area covered by this survey.The chart comparisons were conducted using a combination of SABER and CARIS’ HIPS and SIPS. United States Coast Guard (USCG) District 8 Local Notice to Mariners publications were reviewed for changes subsequent to the date of the Project Instructions and before the end of survey (as specified in Section 8.1.4 of the HSSD). The Notice to Mariners reviewed were from week 19/19 (27 March 2019) until week 48/19 (27 November 2019). H13213 data met data accuracy standards and bottom coverage requirements. Recommend updating the common areas of all charts using data from this survey. Charting recommendations for new features, and updates to charted features, are documented in the H13213 S-57 FFF. Additional charted objects such as submarine pipelines and platforms are discussed in later sections.See the H13213 S-57 FFF for all the details and recommendations regarding new uncharted features investigated.file:///Q:/Survey/H13213_K371_KR_19/AHB_H13213/01_SAR/Reports/Survey/Descriptive_Report/Report/Office/SupportFiles/H13213_Figure_16.jpgDTON ReportThere were no significant shoals or hazardous features within the area covered by this survey the Danger to Navigation (DTON) described below. Leidos submitted one DTON for H13213 consisting of an uncharted wreck in S-57 format to the Atlantic Hydrographic Branch (AHB) on 02 May 2019 which was subsequently submitted to the Nautical Data Brach (NDB) and Marine Chart Division (MCD) on 06 May 2019. Per Section 1.6.1 of the 2019 HSSD, the DTON submission package for this uncharted wreck was submitted with the DTON attributed as an obstruction to ensure that a potentially sensitive feature was not added to the chart without undergoing review by the State Historic Preservation Officer. A copy of the email correspondence for Leidos’ submission of H13213 DTON Report is included within Appendix II of this Descriptive Report. Figure 16 details the submitted DTON and the associated Feature number and object class in the S-57 FFF.No construction or dredging exists for this survey area.No abnormal seafloor or environmental conditions, as defined in Section 8.1.4 of the HSSD, exist within this survey area except as previously discussed in sections B.2.5 and B.2.6 of this report.One charted exposed pipeline and one seep were found within the bounds of H13213. In accordance with HSSD Section 1.7, the exposed pipeline and seep found within H13213 were submitted as a Seep and Pipeline Report. The email correspondence for Leidos’ submission of the H13213 Seep and Pipeline Report is included within Appendix II of this Descriptive Report. The identified exposed pipeline is included in the S-57 FFF. Assigned PIPSOL objects from the CSF, Final_OPR-K371-KR-19_CSF.000, are captured in the S-57 FFF. The one seep identified within the SSS and MBES data of H13213 was found at 29° 35’ 38.99” N 093° 54’ 19.13” W, and identified within the MBES and SSS data to have a form and morphology typical of ascending gas or bubble plumes, but was not found associated with any charted or observed uncharted pipelines or wellheads. The MBES data associated with the seep have been flagged as invalid and therefore were not used in the CUBE depth calculations. SSS contacts were retained on the seep location and are included in the Side Scan Sonar Contact S-57 File, H13213_SSCon.000.There were no overhead features within this survey area.No new survey recommendations are made for the area surrounding this survey area.All features in the CSF within the assigned Survey Limits of H13213 were resolved. There were no assigned features inshore of the NALL.No inset recommendations are made for the area covered by this surveyThere were no aids to navigation that fell within this survey area.Designated SoundingsSeparate flags exist in the Generic Sensor Format (GSF) for a designated sounding and feature. During data analysis, designated soundings or feature flags are used to help better preserve the shallowest sounding relative to the computed depth surface. All depths flagged as features and designated soundings override the CUBE best estimate of the depth in the final BAG files. Both the designated sounding and feature flags, as defined within GSF, are mapped to the same HDCS flag when ingested into CARIS (PD_DEPTH_DESIGNATED_MASK).Final Feature S-57 FileIncluded with H13213 delivery is the S-57 FFF, H13213_FFF.000. Details on how this file was generated and quality controlled can be found in the DAPR. The S-57 FFF delivered for H13213 contains millimeter precision for the value of sounding (VALSOU) attribute. As specified in Section 2.2 of the HSSD, the S-57 FFF is in the WGS84 datum and is unprojected with all depth units in meters. All significant, and recommended for charting, features found in H13213 are included within the S-57 FFF. In accordance with the HSSD, Leidos addressed all assigned objects within the bounds of H13213 from the provided CSF S-57 file in the S-57 FFF. For each feature contained in the FFF (S-57), the Feature Correlator Sheet was exported as an image file (.jpg) and is included in the S-57 FFF under the NOAA Extended Attribute field “images”.Side Scan Sonar Contacts S-57 FileIncluded with the H13213 delivery is the Side Scan Sonar Contact S-57 File, H13213_SSCon.000. Details on how this file was generated and quality controlled can be found in the DAPR. As specified in Section 2.2 of the HSSD, the S-57 file is in the WGS84 datum and is unprojected with all depth units in meters. Side scan sonar contacts were investigated and confirmed using SABER Contact Review. All side scan contacts are retained within the Side Scan Sonar Contact S-57 File. For each contact included in this S-57 file, a JPEG image of the side scan contact is included under the NOAA Extended Attribute field “images”.Coast Pilot Review ReportIn accordance with the Project Instructions and HSSD Section 8.1.3, a Coast Pilot Review was performed for OPR-K371-KR-19. Within the Coast Pilot Field Report (OPR-K371-KR-18CoastPilotReport.pdf) provided by NOAA to Leidos on 18 March 2019, it indicated that paragraphs 15 through 127 were relevant to the survey area of OPR-K371-KR-19 and there were no assigned investigation items . During survey, Leidos reviewed and updated the assigned and additional Coast Pilot paragraphs as possible for the survey area, port of call, and areas frequently transited. Leidos downloaded Coast Pilot 5 Chapter 10 from the Coast Pilot website, 47th Edition of Coast Pilot 5, dated 17 November 2019. Recommendations were documented using the text from the 47th Edition and are marked following the HSSD Section 8.1.3. Leidos followed NOAA’s strategy for designating omitted paragraphs as provided in the delivered Coast Pilot Field Report (OPR-K371-KR-18CoastPilotReport.pdf). Leidos submitted the Coast Pilot Field Report on 22 November 2019. The email correspondence for Leidos’ submission of the Coast Pilot Review Report is included within Appendix II of this Descriptive Report.No ferry routes or terminals exist within this survey area.There were no offshore platform objects assigned in the CSF, Final_OPR-K371-KR-19_CSF.000, provided on 18 March 2019, which fell within the SOW for H13213.The vessel kinematic data (POS/MV files) were post-processed in Applanix POSPac software using the Applanix PP-RTX solution to generate the Smoothed Best Estimate of Trajectory (SBET) solutions which were applied through SABER to the multibeam data. Refer to the DAPR for additional information and for details regarding all antenna and transducer offsets. Any soundings with total horizontal uncertainties exceeding the maximum allowable IHO S-44 5th Edition Order 1a specifications were flagged as invalid and therefore were not used in the CUBE depth calculations.Projected UTM 15North American Datum 1983Mean Lower Low WaterERS via VDATUMRefer to the DAPR for details regarding the application of VDatum to the MBES data files. No final tide note was provided from NOAA Center for Operational Oceanographic Products and Services (CO-OPS). While a final tide note was not required, a final tide note has been provided by Leidos in Appendix I.OPR-K371-KR-19_NAD83_VDatum_MLLW.covAdditional information discussing the vertical and horizontal control for this survey can be found in the OPR-K371-KR-19 DAPR.As Chief of Party, field operations for this hydrographic survey were conducted under my direct supervision, with frequent personal checks of progress and adequacy. I have reviewed the attached survey data and reports.The survey data meets or exceeds requirements as set forth in the Hydrographic Surveys Specifications and Deliverables, Project Instructions, and Statement of Work. These data are adequate to supersede charted data in their common areas. This survey is complete and no additional work is required. Previously, or concurrently, submitted deliverables for OPR-K371-KR-19 are provided in the table below.This Descriptive Report, all BAG files, and all accompanying records and data are approved. All records are forwarded for final review and processing to the Processing Branch.Paul L. DonaldsonChief Hydrographer2019-12-062019-11-22OPR-K371-KR-19_Coast Pilot Review Report.pdf 2019-11-22OPR-K371-KR-19_Marine_Species_Awareness_Training_Record.pdf2019-12-04OPR-K371-KR-19_DAPR.pdf