OPR-K356-KR-23 Approaches to Calcasieu, Louisiana Calcasieu, LA Leidos H13818 3 13 NM South of Mud Lake Louisiana United States 20000 2023 Dorena S. Vogel Navigable Area 2023-07-13 2023-08-21 2023-12-07 Multibeam Echo Sounder Side Scan Sonar Multibeam Echo Sounder Backscatter meters UTC Atlantic Hydrographic Branch Contract: 1305M220DNCNJ0056/TO-04. Contractor: Leidos, 221 Third Street, Newport, RI 02840 USA. Subcontractors: OARS, 8705 Shoal Creek Blvd, Suite 109, Austin, TX 78757. Leidos Doc. 24-TR-006. All times were recorded in UTC. Final data are corrected to 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. CC0-1.0 (NOAA Contractors) CC0-1.0 https://creativecommons.org/publicdomain/zero/1.0/ https://creativecommons.org/publicdomain/zero/1.0/legalcode These data were produced under contract with NOAA and any potential copyright was assigned to NOAA. NOAA waives any potential copyright and related rights in these data worldwide through the Creative Commons Zero 1.0 Universal Public Domain Dedication (CC0). Contractor Leidos conducted hydrographic survey H13818, within the assigned area 13 NM South of Mud Lake, Louisiana (Figure 1). The survey was conducted in accordance with coverage requirements listed in the Project Instructions (PI) OPR-K356-KR-23 and the Statement of Work. Additionally, the survey data were acquired in accordance with Hydrographic Survey Specifications and Deliverables (HSSD), March 2022. 29.627388888888888 93.65353888888889 29.50934722222222 93.36653888888888 H13818 Survey Bounds file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_01.jpg Survey limits were acquired in accordance with the requirements in the PI and the HSSD. The resulting survey limit is shown in Figure 1. The Survey Purpose as defined in the PI: “The area offshore of Calcasieu Lake and Port Charles, Louisiana have been identified as an area in critical need of updated hydrographic data by NOAA's Hydrographic Health models and the Lake Charles Pilot's Association. The Port of Lake Charles is ranked fourteenth by tonnage for U.S. Ports (1), and the region is expected to see an expansion in marine commerce due in part to an increase in LNG distribution, as well as offshore wind-energy development. Since 2020, the Louisiana Coast has been hit by six hurricanes and two named tropical storms, several of which caused serious damage to the Ports of Lake Charles and Calcasieu. Many parts of the coverage area have not been charted since the 1930s. This survey will provide contemporary data to update National Ocean Service (NOS) nautical charting products and services, improving the safety of maritime traffic and services available to the Port of Lake Charles by reducing the current risk that is present due to outdated bathymetry. Survey data from this project is intended to supersede all prior survey data in the common area.” 1: Bureau of Transportation Statistics, 2023. https://www.bts.gov/content/tonnage-top-50-us-water-ports-ranked-total-tons 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 1305M220DNCNJ0056 reflects the state of the sea floor in existence on the day and at the time the survey was conducted. H13818 was surveyed in accordance with the following documents: 1. 1305M223FNCNJ0326 signed.pdf, received 13 July 2023 2. Hydrographic Survey Specifications and Deliverables (HSSD), March 2022 3. NOAA provided Project Reference File (PRF) OPR-K356-KR-23_PRF_FINAL.000, received 13 July 2023 4. NOAA provided Composite Source File (CSF) OPR-K356-KR-23_CSF_FINAL.000, received 13 July 2023 5. OPR-K356-KR-23 Project Brief, held 26 July 2023 All waters in survey area Complete Coverage (Refer All waters in survey area to HSSD Section 5.2.2.3) All waters in survey area where 75-meter range scale is utilized on the side scan sonar. Side scan may be acquired at an altitude of 6-20% of the range scale. Leidos chose to achieve the coverage requirement using Complete Coverage, Option B (100% side scan sonar coverage with concurrent multibeam) over the entire survey area. Multibeam Backscatter was logged continuously during data acquisition. Feature disprovals were conducted in accordance with defined disproval radii from the NOAA provided PRF, HSSD, and PI. Per HSSD Section 5.2.2.3, H13818 depth data fell within one resolution surface (1-meter). Refer to the Data Processing and Acquisition Report (DAPR) for additional information; the DAPR was previously delivered with H13817. Survey coverage achieved was in accordance with the requirements in the PI and the HSSD (Figure 2). Final Bathymetry Coverage for H13818 file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_02.jpg R/V Sea Innovator I 0.0 0.0 0.0 0.0 0.0 2078.46 0.0 94.17 0.0 0.0 0.0 0.0 0.0 0.0 2078.46 0.0 94.17 0.0 4.53 4 0 0 0 78.18 2023-08-21 2023-08-23 2023-08-24 2023-08-25 2023-08-26 2023-08-27 2023-08-28 2023-08-31 2023-09-01 2023-09-02 2023-09-03 2023-09-04 2023-09-05 2023-09-06 2023-09-07 2023-09-08 2023-09-09 2023-09-10 2023-09-11 2023-12-06 2023-12-07 A detailed description of the systems and vessel used to acquire and process these data is included in the DAPR. There were no variations from the vessel or equipment configuration described in the DAPR. The Leidos owned and operated R/V Sea Innovator I was utilized as the survey platform. The R/V Sea Innovator I was used to collect multibeam echo sounder (MBES) (RESON SeaBat T50), side scan sonar (SSS) (Klein 4000), and sound speed data during twenty-four hours per day survey operations. As detailed in the DAPR the data acquisition was logged through Leidos ISS-2000 software and Klein SonarPro; side scan sonar (SSS) only. Post processing and review of MBES and SSS data were conducted in Leidos’ SABER software. R/V Sea Innovator I 135.0 9.0 R/V Sea Innovator I file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_03.jpg MBES Teledyne RESON SeaBat T50-R MBES Backscatter Teledyne RESON SeaBat T50-R SSS Klein Marine Systems System 4000 Positioning and Attitude System Applanix POS MV 320 v5 Conductivity, Temperature, and Depth Sensor AML Oceanographic MVP30 Sound Speed System AML Oceanographic BaseX A detailed description of the equipment installed is included in the DAPR. MBES crosslines acquired 4.53% of H13818 and were distributed spatially and temporally across the sheet and survey duration per HSSD. The resulting crossline to mainscheme percentage met the requirement to achieve approximately four percent of mainscheme mileage for a complete coverage multibeam survey (Section 5.2.4.2 of the HSSD). H13818 requirements were for Complete Coverage, Option B, based on the classifications defined in Section 5.2.2.3 of the HSSD. Refer to the DAPR, Section D.1.5 for details for Leidos conducting the repeatability analysis of mainscheme and crossline data. Crossline analysis was conducted within SABER, utilizing a 1-meter difference grid between the CUBE depth of mainscheme data and CUBE depth of near nadir cross line data. The SABER Frequency Distribution Tool was used to statistically analyze the difference grid created from the mainscheme and crossline PFM grids; results are summarized in Figure 4. Section 5.2.4.2 of the HSSD states that the depth difference values are to be within the maximum allowable Total Vertical Uncertainty [TVU]. For H13818, 100% of the comparisons were within TVU for crossing analysis as summarized in Figure 5 and Figure 6. Summary of Crossing Analysis file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_04.jpg Tabular Results Crossing Analysis, Crosslines vs. Mainscheme Lines file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_05.png Plot of Crossing Analysis Crosslines vs. Mainscheme Lines file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_06.png ERS via VDATUM 0.012 0.2 R/V Sea Innovator I N/A 1.0 N/A 1.0 For 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 Interval (CI). 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 6th Edition, Order 1a were flagged as invalid during the uncertainty attribution. As referenced in the DAPR, Leidos analyses the grid surface several ways to verify that the data meet IHO S-44 6th Edition, Order 1a. The first is to analyze the range of derived uncertainty across the sheet and second is to compare each CUBE depth’s allowable uncertainty. The second method utilizes a statistical tool within SABER which outputs a designation if the allowable uncertainty exceeded IHO 6th Ed. Order 1a. For H13818, none of the nodes in the final surface had final vertical uncertainties that exceeded IHO Order 1a allowable vertical uncertainty. The final uncertainty surface contained vertical uncertainties from 0.280 meters to 0.500 meters. The IHO Order 1a maximum allowable vertical uncertainty was calculated to range between 0.517 to 0.529 meters, based on the minimum CUBE depth (10.039 meters) and maximum CUBE depth (13.185 meters). Further analysis was conducted to compute statistical analysis on the vertical uncertainty surface using SABER’s Frequency Distribution Tool; results showed that 100.00% of all nodes had final uncertainties less than or equal 0.500 meters, within the maximum allowable. Per the Project Instructions, junction analysis was performed between H13818, and the surveys listed in the Table 9 below and illustrated in Figure 7; results are discussed below. General Locality of H13818 with Junctioning Surveys file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_07.jpg H12727 40000 2015 Leidos S Repeatability analysis was conducted by comparing the H12727 1-meter BAG depth surface to the H13818 1-meter BAG depth surface. The overlapping area was approximately 23,200 by 300 meters. Within the common area, observed depths were 9.688 to 12.514 meters which resulted in a calculated allowable TVU range of 0.516 to 0.526 meters. Results, show in Figure 8 indicate that 99.93% of the comparisons were 0.500 meters or less, within the calculated allowable TVU range. The distribution is skewed positive of zero as presented in Figure 9. Tabular Results Junction Analysis H13818 vs. H12727 file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_08.png Plot of Junction Analysis H13818 vs. H12727 file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_09.png H13644 10000 2022 DEA E Repeatability analysis was conducted by comparing the H13644 50-centimeter BAG depth surface to the H13818 1-meter BAG depth surface. The overlapping area was approximately 3,240 by 225 meters. Within the common area, observed depths were 10.822 to 12.158 meters which resulted in a calculated allowable TVU range of 0.519 to 0.524 meters. Results, show in Figure 10 indicate that 100.00% of the comparisons were 0.298 meters or less, within the calculated allowable TVU range. The distribution is skewed positive of zero as presented in Figure 11. Tabular Results Junction Analysis H13818 vs. H13644 file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_10.png Plot of Junction Analysis H13818 vs. H13644 file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_11.png H13645 10000 2022 DEA E The H13645 1-meter BAG file (2of2) had coincident data with H13818. Leidos conducted repeatability analysis by comparing the H13645 1-meter BAG depth surface to the H13818 1-meter BAG depth surface. The overlapping area was approximately 3,000 by 260 meters. Within the common area, observed depths were 11.770 to 12.437 meters which resulted in a calculated allowable TVU range of 0.523 to 0.525 meters. Results, show in Figure 12 indicate that 100.00% of the comparisons were 0.383 meters or less, within the calculated allowable TVU range. The distribution is skewed positive of zero as presented in Figure 13. Tabular Results Junction Analysis H13818 vs. H13645 file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_12.png Plot of Junction Analysis H13818 vs. H13645 file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_13.png H13648 10000 2022 DEA N Repeatability analysis was conducted by comparing the H13648 1-meter BAG depth surface to the H13818 1-meter BAG depth surface. The overlapping area was approximately 22,030 by 300 meters. Within the common area, observed depths were 10.445 to 11.591 meters which resulted in a calculated allowable TVU range of 0.518 to 0.522 meters. Results, shown in Figure 14 indicate that 99.99% of the comparisons were 0.360 meters or less, within the calculated allowable TVU range. The distribution is skewed positive of zero as presented in Figure 15. Tabular Results Junction Analysis H13818 vs. H13648 file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_14.png Plot of Junction Analysis H13818 vs. H13648 file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_15.png H13816 10000 2023 Leidos W Repeatability analysis was conducted by comparing the H13816 1-meter BAG depth surface to the H13818 1-meter BAG depth surface. The overlapping area was approximately 4,000 by 150 meters. Within the common area, observed depths were 12.147 to 12.587 meters which resulted in a calculated allowable TVU range of 0.524 to 0.526 meters. Results, show in Figure 16 indicate that 100.00% of the comparisons were 0.270 meters or less, within the calculated allowable TVU range. The distribution is skewed negative of zero as presented in Figure 17. Tabular Results Junction Analysis H13818 vs. H13816 file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_16.png Plot of Junction Analysis H13818 vs. H13816 file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_17.png H13817 10000 2023 Leidos SE Repeatability analysis was conducted by comparing the H13817 1-meter BAG depth surface to the H13818 1-meter BAG depth surface. The overlapping area was approximately 13,000 by 180 meters. Within the common area, observed depths were 10.223 to 11.834 meters which resulted in a calculated allowable TVU range of 0.517 to 0.523 meters. Results, show in Figure 18 indicate that 100.00% of the comparisons were 0.360 meters or less, within the calculated allowable TVU range. The distribution is centered on zero as presented in Figure 19. Tabular Results Junction Analysis H13818 vs. H13817 file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_18.png Plot of Junction Analysis H13818 vs. H13817 file:///B:/OPR-K356-KR-23/Surveys/H13818/01_HDR/Reports/Descriptive_Report/SupportFiles/H13818_Figure_19.png Sonar system quality control checks were conducted as detailed in the DAPR. RESON SeaBat T50-R As discussed in the DAPR the RESON SeaBat T50-R exhibited degradation during OPR-K356-KR-23 and was replaced. Data acquisition was able to continue until the unit was swapped as data quality was not impacted and data acquired were validated. Refer to the DAPR for when the RESON SeaBat T50-R transducer was replaced. None Exist There were no other factors that affected corrections to soundings. On the R/V Sea Innovator I, the MVP30 was the primary system 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. 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. All individual SSP files are delivered with the H13818 data and are broken out into sub-folders, which correspond to the purpose of each cast. Also, all individual SSP files for H13818 have been concatenated into two separate files based on the purpose of the cast, provided in CARIS format files (.svp), and delivered under (H13818/Processed/SVP/CARIS_SSP) on the delivery drive. In accordance with HSSD Section 8.3.6, SSP files were also converted to NCEI format, as detailed in the DAPR, and will be provided as a separate delivery to NCEI. All equipment and survey methods are detailed in the DAPR. For H13818, Leidos chose to achieve the complete coverage requirement using Complete Coverage, Option B (100% side scan sonar coverage with concurrent multibeam). To achieve this coverage and to continue to conduct survey during periods of weather; the SSS was set to either 75-meter or 50-meter range scale. Per the PI if an OFSPLF was not present during data acquisition a formal disproval did not need to be conducted. Leidos utilized SABER’s Gapchecker program to flag MBES data gaps within the final CUBE surface as well as within the SSS mosaics. Surfaces also visually scanned for holidays throughout the data processing effort. During data acquisition, additional lines were run to fill holidays that were detected. Bathymetric data and side scan sonar imagery were reviewed and bathymetric splits were acquired if deemed necessary per Hydrographer’s discretion, as noted in Section 5.2.2.1 of the HSSD. A final review of the CUBE depth surface showed that there were no holidays as defined for Complete Coverage surveys in HSSD Section 5.2.2.3. Any remaining three by three unpopulated nodes in the final MBES surfaces were along the outer swath data, beyond the side scan nadir coverage gap, and fully covered with 100% SSS coverage. For all details regarding SSS data processing, see the DAPR. Leidos generated SSS coverage mosaic at 1-meter cell size resolution as specified in HSSD Section 8.2.1, note that 200% SSS disproval mosaic was not required or obtained for H13818. The SSS 100% coverage mosaic was reviewed using tools in SABER to verify data quality and swath coverage. The SABER Gapchecker routine was used to flag data gaps within this mosaic. Additionally, the entirety of the 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. The coverage mosaic is determined to be complete and sufficient to meet the requirements contained within the PI and HSSD. The SSS coverage mosaic is delivered as a single georeferenced raster file (datum of NAD-83) in floating point GeoTIFF format, as specified in Sections 8.2.1 and 8.3.3 in the HSSD. Multibeam Sounding Density The Frequency Distribution Tool was used to analyze the number of soundings which contributed to the chosen CUBE hypothesis; to verify HSSD Section 5.2.2.3 for 95% of nodes to be populated with at least 5 soundings. Within the final 1-meter CUBE surface 99.46% of all nodes contained five or more soundings. All data reduction procedures conform to those detailed in the DAPR. All sounding systems were calibrated as detailed in the DAPR. For all details regarding MBES backscatter acquisition and processing see the DAPR. 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 under the Processed/Sonar_Data/H13818_MB directory. Leidos followed previous guidance from NOAA to deliver the data in a single directory only as the data files are identical; therefore the raw directory is not populated. Final MBES backscatter were mosaicked at 2-meter cell resolution. The MBES backscatter mosaics were reviewed for data quality and coverage. There were minor artifacts present in the MBES backscatter coverage; as discussed in the DAPR MBES settings were not adjusted in real-time to reduce impact to the MBES backscatter. Leidos verified that in these areas there are no CUBE artifacts. The MBES backscatter artifacts do not impact resulting coverage. All MBES backscatter mosaics are determined to be complete and sufficient to meet the requirements contained within the PI and HSSD. The coverage mosaics are delivered as a georeferenced raster file(s) (datum of NAD-83) in floating point GeoTIFF format, as specified in HSSD Section 6.2.4.2. Leidos SABER 6.0.3.2.2 Leidos SABER 6.0.3.2.2 QPS FMGT 7.10.3 NOAA Profile Version 2023 The primary data processing software used for both bathymetry and imagery was SABER. H13818_MB_1m_MLLW_Final BAG 10.039 13.185 N/A Complete MBES H13818_SSSAB_1m_400kHz_1of1 SSS Mosaic 0.0 0.0 N/A 100% SSS H13818_MBAB_2m_SeaInnovatorI_350kHZ_1of3 MB Backscatter Mosaic 0.0 0.0 N/A Complete MBES H13818_MBAB_2m_SeaInnovatorI_350kHZ_2of3 MB Backscatter Mosaic 0.0 0.0 N/A Complete MBES H13818_MBAB_2m_SeaInnovatorI_350kHZ_3of3 MB Backscatter Mosaic 0.0 0.0 N/A Complete MBES Complete Coverage HSSD Section 5.2.2.3 requires 1-meter grid resolution for depths ranging from 0 meters to 20 meters. Leidos generated the CUBE PFM grids for H13818 at 1-meter resolution. The final gridded MBES data are delivered in Bathymetric Attributed Grid (BAG) format as detailed in the DAPR. In accordance with HSSD Section 2.2, the horizontal datum for this project is NAD83. HSSD Section 2.2 states that the “only exception for the NAD83 datum requirement is that the S-57 Final Feature File (Section 7.3) will be in the WGS84 datum to comply with international S-57 specifications.” As discussed in the DAPR Section C.7, for every feature flag in a MBES GSF file, SABER converts the position from the NAD83 datum to the WGS84 datum to generate the S-57 file and comply with HSSD and IHO requirements. Feature positions meet the precision stated in HSSD Section 7.4 for each respective datum. Depending on geographic reference there may be approximately a 1-meter difference comparing positions between NAD83 and WGS84 datums. Therefore, if the feature overrides from the BAG surface (NAD83) are compared to the Final Feature File S-57 positions (WGS84) it is anticipated that there could be positional differences exceeding those listed in Section 7.4 of the HSSD. Additional information discussing the vertical and horizontal control for this survey can be found in the DAPR. Mean Lower Low Water ERS via VDATUM OPR-K356-KR-23_NAD83_VDatum_MLLW.cov Final MBES data are reduced to MLLW through VDatum; refer to the DAPR for additional information. No final tide note was provided nor was it required from NOAA Center for Operational Oceanographic Products and Services (CO-OPS). North American Datum 1983 Projected UTM 15 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 MBES 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 6th Edition Order 1a specifications were flagged as invalid and therefore do not contribute the CUBE depth calculations. Chart comparisons were conducted using a combination of SABER and CARIS’ HIPS and SIPS. H13818 data met data accuracy standards and bottom coverage requirements. Charting recommendations for new features and updates to charted features, are documented in the H13818 FFF. Additional charted objects are discussed in later sections within this DR. United States Coast Guard (USCG) District 8 Local Notice to Mariners (LNM) publications were reviewed for changes subsequent to the date of the Project Instructions and through final processing. The LNM reviewed were from week 30/23 (26 July 2023) until week 02/24 (10 January 2024). Leidos noted that an offshore platform (OFSPLF) which was coincident to H13818, was documented within the LNM; refer to Section D.2.6 and the H13818 FFF for final charting recommendations. Platform located at 29° 33’ 34.926”N 093° 25’ 27.778”W was listed in LNM 30/23 through LNM 02/24 as ‘LT EXT/SS INOP’. During survey operations, the 4 flashing lights on the OFSPLF corners and the whistle were confirmed to be operational. Review showed that the H13818 CUBE data were generally in agreement with charted depths. Compared to the ENC’s listed in Section D.1.1. CUBE depths generally agreed with the charted depths within ±0.3-1.0 meters and were generally found to be deeper than charted. Leidos recommends updating the common areas of all charts using data from this survey. US4LA10M 80000 23 2024-02-09 2024-02-09 US4TX71M 80000 43 2023-10-03 2023-11-20 US5LCCHEA 20000 1 2023-06-13 2023-12-20 US5LCHFA 20000 1 2023-06-13 2023-12-20 US5POABE 20000 1 2023-05-02 2023-07-25 US5POACE 20000 1 2023-05-02 2023-05-02 Refer to Section D.1.4 for significant shoals or hazardous features within the area covered by this survey. Refer to the H13818 FFF (H13818_FFF.000). There were numerous assigned charted features in the final CSF within the SOW of H13818. Per HSSD Section 8.1.4, these charted features are not addressed in this section, refer to the H13818 FFF (H13818_FFF.000) for all the details and recommendations regarding these features. Assigned features from the NOAA provided CSF were addressed within H13818 and are included in the H13818 FFF. Any charted features that were disproven are also included within the H13818 FFF with assignment flag of Delete. See the H13818 FFF for details and recommendations regarding new uncharted features investigated during this survey. There were no assigned channels within the H13818 SOW from the final CSF. During the transit to and from port throughout OPR-K356-KR-23 Leidos observed shoaling within the Cameron Loop. This was submitted as a DTON to NOAA and is not directly associated with any sheet within this Project; refer to Project Correspondence. There were no assigned Aids to Navigation (ATON) within the SOW of H13818 from the final CSF. There were no ATONs within the surveyed area. No Maritime Boundary Points were assigned for this survey. In accordance with both the PI and Section 7.2.3 of the HSSD, bottom characteristics were obtained for H13818. Bottom characteristics were acquired as assigned from the PRF; Leidos did not modify the bottom sample locations from the location proposed by NOAA in the PRF. Bottom characteristics are included in the H13818 FFF. In addition, images of the sediment obtained for each bottom sample are referenced in the FFF and are included on the delivery drive under the folder H13818/Processed/Multimedia. There were no overhead features within this survey area. Within the final CSF, there was several assigned submarine features for investigation. All assigned and new submarine features are detailed within the H13818 FFF. Non-dangerous, unburied sections of pipelines were observed within the H13818 MBES and SSS data. As these fell outside the bounds of the State of Louisiana CZMA, they were submitted to BSEE and NOAA following HSSD Section 1.7.3; refer to Appendix II and Project Correspondence. All exposed pipelines were approximately within 0.5m of the surrounding depth area and determined to be non-dangerous. SSS contacts were retained on the non-dangerous pipelines and are included in the Side Scan Sonar Contact S-57 File. Platforms are addressed within the H13818 FFF. As noted in Section D.1, one platform coincident to H13818 was documented within the LNM. No ferry routes or terminals exist for this survey. No other abnormal seafloor or environmental conditions, as defined in HSSD Section 8.1.4, exist within this survey area. No construction or dredging exists within this survey area. No new surveys or further investigations are recommended for this area. No new ENC scales are recommended for this area. 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. This Descriptive Report and all accompanying records and data are approved. All records are forwarded for final review and processing to the Processing Branch. The survey data meets or exceeds requirements as set forth in the Hydrographic Survey 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-K356-KR-23 are provided in the table below. Dorena S. Vogel Lead Hydrographer 2024-03-08 OPR-K356-KR-23 Final Project Summary Report.pdf 2024-01-05 OPR-K356-KR-23_Coast Pilot Review Report.pdf 2024-01-09 OPR-K356-KR-23_ Marine_Species_Awareness_ Training_Record.pdf 2024-01-30 OPR-K356-KR-23_DAPR.pdf 2024-03-05 H13817_DR.pdf 2024-03-05 H13816_DR.pdf 2024-03-07