Sindy M. Mejia Emily H. Majcher Ellie P. Foss Andrew W. Psoras Jason H. Chase Trevor P. Needham 20250630 tabular digital data https://doi.org/10.5066/P14RSCHZ These data were collected as part of a study that used a sediment fingerprinting model to better understand sources of PCB-contaminated suspended sediments within stormflow in the Back River watershed. This metadata record contains 4 tables of data used to model and assess the source of storm sediment collected within the Back River watershed in Maryland in 2023. Included in the dataset are analytical results from sediment samples collected from the landscape, in stream banks, during storms using passive samplers, and intact cores, and analyzed for (1) PCB, (2) elemental metals and carbon content, and (3) grain size. Also included are calculated PCB concentrations in porewater using sediment concentration from storm and core samples. These data were collected to conduct sediment fingerprinting modeling using SedSat (Gorman, Senisaca and others,2017) and to assess the bioavailability of PCB from storm-deposited sediment. 20230110 20231208 observed Complete None planned Maryland -76.6166 -76.4911 39.4172 39.2982 ISO 19115 Topic Category inlandWaters geoscientificInformation None Back River watershed Marine Realms Information Bank (MRIB) keywords sediment stormwater SedSat PCB USGS Thesaurus Geochemistry Sedimentology Water Quality USGS Metadata Identifier USGS:66e7a9d0d34e0606a9db9555 None. Please see 'Distribution Info' for details. None. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations. U.S. Geological Survey, Northeast Region Sindy M. Mejia Physical Scientist mailing and physical

5522 Research Park Drive

Baltimore Maryland 21228 US 410-925-8098 smejia@usgs.gov Data collection was made possible through funding provided by the Baltimore City Department of Public Works (DPW) and the United States Geological Survey Urban Waters Cooperative Matching Fund. The data included in this release were collected and analyzed by USGS laboratories at the Maryland-Delaware-D.C. Water Science Center (USGS MD-DE-DC WSC, Baltimore, Maryland), and the Geology, Geophysics, and Geochemistry Science Center (USGS GGGSC, Lakewood, Colorado). The Back River PCB Data table containing concentrations in sediment samples was produced using Microsoft Excel 365 v2402, in a Windows 11 Enterprise v23H2 environment. This file is 41.9 kilobytes and is in comma-delimited (.csv) format. The Back River PCB Bio-availability Data table containing concentrations in porewater from sediment concentrations using equilibrium partitioning data was produced using Microsoft Excel 365 v2402, in a Windows 11 Enterprise v23H2 environment. This file is 15.0 kilobytes and is in comma-delimited (.csv) format. The Back River Elemental Carbon and Grain size Data table containing elemental metals, carbon and grain size data was produced using Microsoft Excel 365 v2402, in a Windows 11 Enterprise v23H2 environment. This file is 24.1 kilobytes and is in comma-delimited (.csv) format. Quality assurance (QA)/quality control (QC) procedures were completed by the USGS staff and reporting laboratory and are summarized here. Quality assurance data included trip and equipment blanks, and duplicate samples. In addition, laboratory method blanks, surrogate recoveries, and calibrations all met acceptable criteria or are qualified as described in the quality assurance columns. A trip blank with PCB-free sand was prepared daily in the USGS MD-DE-DC WSC before departure and kept in the designated cooler where all other samples were stored during each field day. An equipment blank with PCB free sand was prepared once per sampling week upon arrival at the first location. The equipment blank sand was poured onto the surface of designated clean stainless-steel hand garden trowels that were used for sampling and into the sample container and stored in the designated cooler with the rest of the samples for the day. Duplicate samples of at least 20% of the total samples were collected from randomly selected locations to measure inter-sample variability, reproducibility and precision of laboratory extractions and field methods. Qualifiers for the datasets and their respective definitions are below: Data qualifying codes for all tables are found in their qualifier columns and noted with descriptions, where applicable. The data includes processes descriptions for samples collection, handling logistics and analysis for PCB, grain size, elemental metals, and carbon. A horizontal accuracy test was not performed for this dataset. A vertical accuracy test was not performed for this dataset. Sediment sample collection: Sediment grab samples were collected from randomly selected residential and commercial-industrial roadways in areas near stormwater drains. USGS staff used a PTFE-coated stainless-steel scoop to transfer material at storm drains into the respective sample containers. These included a clean 40-mL VOA glass vial for PCB analysis, a 15-mL poly-propylene conical Falcon tube for elemental metals and total carbon analysis, and a 0.7 quart plastic bag for particle size analysis. Sediment grab samples were collected from randomly selected greenspace designated areas. These samples were comprised of composites from one to three 10 meter transects. The transects were cleared of grass and the uppermost 0.5 centimeters of the soil was collected using a stainless-steel garden trowel and placed into a site-designated, 2-gallon food-grade bucket. The sample was homogenized using a clean and decontaminated PTFE-coated scoop. After homogenization, the sediment was transferred into the sample containers as detailed for the previous grab samples. Sediment samples of eroded stream banks were comprised of composite samples falling within 25 feet upstream and downstream of the target location. When feasible, both sides of the stream were sampled for the target location. Sediment was collected using a stainless-steel hand garden trowel and by scraping the face of the bank from top to bottom, (Noe and others, 2020). Composites were homogenized in a site-designated 2-gallon bucket and distributed to sample containers as previously described. Noe, Gregory & Cashman, Matthew & Skalak, Katie & Gellis, Allen & Hopkins, Kristina & Moyer, Douglas & Webber, James & Benthem, Adam & Maloney, Kelly & Brakebill, John & Sekellick, Andrew & Langland, Mike & Zhang, Qian & Shenk, Gary & Keisman, Jeni & Hupp, Cliff. (2020). Sediment dynamics and implications for management: State of the science from long‐term research in the Chesapeake Bay watershed, USA. WIREs Water. 7. 10.1002/wat2.1454. Suspended sediment was collected using passive samplers as described by Phillips and others (2000). Samplers were fixed to rocks using butterfly clamps at two locations in the Herring Run tributary to Back River. The passive samplers were deployed before anticipated storms and left to collect sediment for the duration of a storm event or multiple storm events. Samplers were retrieved and the contents were poured into a clean food-grade 5-gallon bucket. The buckets were left in a refrigerator for 7-10 days to allow the suspended sediment to settle. Afterward the water was decanted using a peristaltic pump with clean Master flex C-Flex tubing. The sediment was then transferred to a clean 125-mL wide-mouth glass jar, homogenized and distributed into the sample containers for analysis as previously described. Sediment cores were collected from the depositional mudflat area near the upper tidal zone of the Back River using a 2-inch butyrate tube. The tubes were advanced by hand to a depth of 25 centimeters. The cores were transported to the lab, frozen and later sampled in the lab following the same procedures as the storm sediment sampling described above. All field samples were transported on wet ice to the USGS MD-DE-DC WSC. PCB samples were frozen and then freeze-dried for analysis. Elemental metals and carbon samples were frozen until they were sent out for analysis. Grain size samples were kept refrigerated before analysis. All sediment samples were analyzed for the same suite of constituents including PCB, grain size, elemental metals, and carbon content. 20231208 PCB concentrations for bioavailability data were calculated using organic carbon-water partitioning coefficients(Koc) estimated by linear regression from Booij (2003) and octanol-water coefficients (Kow) from Smedes and others (2009) and Hawker and others (1988). The concentrations of sediment samples and extracts from polyethylene (PE) passive samplers were used to validate the applicability of the estimated Koc. PCB bioavailability passive samplers consisted of PE sheets cut into 2 cm x 3 cm pieces which were cleaned and dosed with reference compounds. The prepared PE sheets were skewered with stainless-steel wire to eliminate buoyancy. One PE passive sampler device was inserted into each 20 mL amber VOA vial containing wet sediment from selected sediment samples covered with Ultra High Purity (UHP) water to saturate and remove visible head space. The PE passive sampler devices within the vials were equilibrated by rolling for 60 days at 1 rpm. The extraction methods for the PE passive samplers are described in Needham and Ghosh (2019). Analysis of PCB in sediment and passive samplers was performed and reported by the USGS MD-DE-DC WSC Analytical Laboratory staff following U.S. EPA Method 8082 for extraction and gas chromatography-tandem mass spectrometry (GC-MS/MS) using an Agilent 7000A mass spectrometer in the multiple reaction monitoring (MRM) mode following a modified form of U.S. EPA Method 1628. The use of congener-level PCB calibration followed Mullin (1994) and utilized MS/MS transitions from Bako and others (2021). Laboratory analytical methods for extractions and cleanup of sediment samples were performed as described in the referenced scientific investigations report from Majcher and others (2022). Booij, K., Hoedemaker JR, Bakker, J.F. Dissolved PCBs, PAHs, and HCB in pore waters and overlying waters of contaminated harbor sediments. Environmental Science & Technology. 2003, 37 (18), 4213-4220. https://doi.org/10.1021/es034147c. Smedes, F., Geertsma, R. W., Zande, T. V. D., Booij, K. Polymer−Water Partition Coefficients of Hydrophobic Compounds for Passive Sampling: Application of Cosolvent Models for Validation. Environmental Science & Technology. 2009, 43 (18), 7047–7054. https://doi.org/10.1021/es9009376. Hawker, D. W., Connell, D. W. Octanol-Water Partition Coefficients of Polychlorinated Biphenyl Congeners. Environmental Science & Technology. 1988, 22 (4), 382–387. https://doi.org/10.1021/es00169a004. Needham, T. P., Ghosh, U. Four Decades since the Ban, Old Urban Wastewater Treatment Plant Remains a Dominant Source of PCB to the Environment. Environmental Pollution 2019, 246, 390–397. https://doi.org/10.1016/j.envpol.2018.12.016. U.S. EPA. July 1996. "Method 8082: Polychlorinated Biphenyls (PCB) by Gas Chromatography.” Washington, DC. https://archive.epa.gov/epawaste/hazard/testmethods/web/pdf/method%208082%2c%20revision%200%20-%201996.pdf U.S. EPA. July 2021. "Method 1628: Polychlorinated Biphenyls (PCB) Congeners in Water, Soil, Sediment, Biosolids, and Tissue by Lo-resolution GC/MS using Selected Ion Monitoring. Washington, DC. https://www.epa.gov/system/files/documents/2021-07/method-1628_pcb-congeners-by-low-resolution-gc-ms_july-2021.pdf Mullin, M. PCB Congener Quantification for Lake Michigan Mass Balance Study. EPA National Health and Environmental Effects Research Laboratory, Grosse Ille, MI, 1994. https://www.epa.gov/greatlakes/lake-michigan-mass-balance-results-and-publications Bako, C. M., Mattes, T. E., Marek, R. F., Hornbuckle, K. C., Schnoor, J. L. Biodegradation of PCB Congeners by Paraburkholderia Xenovorans LB400 in Presence and Absence of Sediment during Lab Bioreactor Experiments. Environmental Pollution 2021, 271, 116364. https://doi.org/10.1016/j.envpol.2020.116364. Majcher, E., Ghosh, U., Needham, T.P., Lombard, N., Foss, E.P., Bokare, M., Joshee, S., Cheung, L., Damond, J., and Lorah, M., 2022, Refining Sources of Polychlorinated Biphenyls in the Back River watershed, Baltimore, Maryland, 2018-2020: U.S. Geological Survey Scientific Investigations Report, https://pubs.usgs.gov/sir/2022/5012/sir20225012.pdf 20240108 Elemental metals, carbon, and grain size analyses: Elemental metals and total organic carbon analyses were performed and reported by the USGS Geology, Geophysics, and Geochemistry Science Center in Lakewood, Colorado. Sample Preparation for all sediment samples for both analyses as mentioned above followed Method 1 of their 40 Methods summaries accessible online. Total organic carbon analysis incorporates methods 2 for total sulfur, 3 for total carbon, and 4 for carbonate carbon (inorganic carbon). These methods were used to calculate the total organic carbon for each sample. In Methods 2 and 3, sample material is combusted and the resulting gases are measured by infrared detection on a LECO instrument. In method 4, perchlorich acid is added to the sample to release carbon dioxide which is then measured by infrared detection. Elemental metals analysis followed method 17. The material undergoes decontent by multi-acid digestion followed by Inductively Coupled Plasma-Optical Emission Spectometry-Mass Spectrometry (ICP-OES-ES) analysis. USGS (2022, September 30). Analytical Chemistry. Geology, Geophysics, and Geochemistry Science Center. Retrieved September 25, 2024, from https://www.usgs.gov/centers/gggsc/science/analytical-chemistry Grain size analysis was performed and reported by the USGS MD-DE-DC WSC Sediment Laboratory. The particle size analysis followed an internal standard operating procedure using methods outlined in the journal article by Gellis and others, (2019). Grain size methods differed from those detailed in this journal article in the following two ways: 1) Grain size analysis of fine sediment was conducted using a HORIBA Partica LA-960V2 laser scattering particle size distribution analyzer. 2) An aliquot (0.0235-0.0265 g) of each sample was transferred into a 20-mL scintillation vial. Gellis, A.C, Fuller, C.C., Van Metre, P.C., Filstrup, C.T., Cole, K. Sabitov, T. Combining sediment fingerprinting with age-dating sediment using fallout radionuclides for an agricultural stream, Walnut Creek, Iowa, USA. J Soils Sediments 19, 3374-3396 (2019). https://doi.org/10.1007/s11368-018-2168-z 20240228 Vector Entity point 62 .0197513196 .0254118316 Decimal seconds North American Datum of 1983 (NAD 83) Geodetic Reference System 1980 6378137.000000 298.257222 BackRiver_Elemental_C__GrainSz_Data.csv Comma Separated Value (CSV) file containing data for fine sediment content, organic, total and acid soluble carbon and elemental metal concentrations expressed as percentages or milligrams per kilogram of dry weight for all sediment samples collected. USGS Defined Sample_ID The sample ID is a USGS generated unique sample identifier consisting of 3 letters (BRS) for Back River sediment and a unique 6-digit number. Suffixes designate the primary (.1) or secondary/duplicate (.2) sample for that location or sample. Samples with additional suffixes such as (-10) and (-20) indicate the depth below land surface in centimeters from where that core sediment sample was collected. Quality control blank samples consist of the same naming scheme of 3 letters (BRS) with a different series (91XXXX) for equipment blanks as the unique 6-digit number. USGS Defined These are sample identifiers without scientific significance. Please refer to the attribute definition above for the naming convention details. Sample_Name The sample name indicates the origin of each sediment sample. Sample names begin with 2 letters (HR) for Herring Run and sequential numbers from 1-65 for land source samples and storm samples. Storm samples names include a descriptive suffix (PSS) indicating the use of a passive sampler and the storm event number. Core sample names begin with "Core" followed by a number for their location (1,3 or 4), and the depth below land surface in centimeters (CXX) from which the sample was acquired. Quality control blank sample names consist of the letters (EB) for equipment blank and the date they were collected in the following format -MMDDYYYY. USGS Defined These are sample identifiers indicating the origin of each sample. Please refer to the attribute definition above for the naming convention details. Sample_Date Date when the sample was collected from the site formatted as MM/DD/YYYY. USGS Defined 1/10/2023 12/13/2023 Sample_Type Sample source type USGS Defined Residential Sediment sample collected from the roadway storm drain closest to the randomly selected residential parcel. USGS defined Commercial Industrial Sediment sample collected from the roadway storm drain closets to the randomly selected commercial or industrial parcel. USGS defined Greenspace Composite sediment sample collected from vegetated or partially vegetated land. USGS defined Streambank city Composite sediment sample collected from eroded banks within Baltimore City. USGS defined Streambank county Composite sediment sample collected from eroded banks within Baltimore County. USGS defined Storm Suspended sediment sample from a storm event passive sampler. USGS defined Core Sediment collected from below land surface via advancing a tube by hand. USGS defined Equipment blank Quality control material(clean, baked sand) that should not contain any analytes processed identically to the samples. USGS defined Latitude Coordinate that specifies the north-south position of the sample point on the surface of the Earth. USGS Defined 38.335193 39.400466 Decimal degrees. Longitude Coordinate that specifies the east-west position of the sample point on the surface of the Earth. USGS Defined -76.610001 -76.498249 Decimal degrees. D50 Median diameter for fine sediment in the sample. USGS Defined 8.842 30.367 Micrometers OC_percentage Calculated percent of organic carbon in the sample provided by the reporting laboratory. The value reported is the total carbon minus the inorganic (carbonate) carbon, expressed as a percentage. USGS Defined 0.01 20.28 Percent organic carbon. TC_percentage The fraction of total carbon in each sediment sample expressed as a percentage. USGS Defined 0.017 20.29 Percent total carbon. CO2_C_percentage The fraction of acid-soluble carbon in each sediment sample expressed as a percentage. USGS Defined 0.05 24.78 Percent acid-soluble carbon. CO2_C_QA Quality assurance flag for acid-soluble carbon. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined - No qualifiers associated with the reported value. USGS defined U The measured concentration is less than the LOD. The reported concentration is equal to the LOD. USGS defined CRBNT_C_percentage The fraction of carbonate (inorganic) carbon in each sediment sample expressed as a percentage. USGS Defined 0.01 6.76 Percent carbonate carbon. Al_percentage The aluminum content in each sediment sample expressed as a percentage. USGS Defined 0.15 6.00 Percentage Al_QA Quality assurance flag for aluminum content. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Ca_percentage The calcium content in each sediment sample expressed as a percentage. USGS Defined 0.01 13.40 Percentage Ca_QA Quality assurance flag for calcium content. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Fe_percentage The iron content in each sediment sample expressed as a percentage. USGS Defined - 6.22 Percentage Fe_QA Quality assurance flag for iron content. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined K_percentage The potassium content in each sediment sample expressed as a percentage. USGS Defined - 2.80 Percentage K_QA Quality assurance flag for potassium content. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Mg_percentage The magnesium content in each sediment sample expressed as a percentage. USGS Defined - 6.09 Percentage Mg_QA Quality assurance flag for magnesium content. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Na_percentage The sodium content in each sediment sample expressed as a percentage. USGS Defined - 1.54 Percentage Na_QA Quality assurance flag for sodium content. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined S_percentage The sulfur content in each sediment sample expressed as a percentage. USGS Defined - 0.21 Percentage S_QA Quality assurance flag for sulfur content. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Ti_percentage The titanium content in each sediment sample expressed as a percentage. USGS Defined - 1.16 Percentage Ti_QA Quality assurance flag for titanium content. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Ag_mg_kg The silver concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 1.46 Milligrams per kilogram. Ag_QA Quality assurance flag for silver concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined As_mg_kg The arsenic concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 10.00 Milligrams per kilogram. As_QA Quality assurance flag for arsenic concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined U The measured concentration is less than the lower reporting limit (LRL). The reported concentration is equal to the LRL. USGS defined Ba_mg_kg The barium concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 997.00 Milligrams per kilogram. Ba_QA Quality assurance flag for barium concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Be_mg_kg The beryllium concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 651.00 Milligrams per kilogram. Be_QA Quality assurance flag for beryllium concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Bi_mg_kg The bismuth concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 2.70 Milligrams per kilogram. Bi_QA Quality assurance flag for bismuth concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined U The measured concentration is less than the LOD. The reported concentration is equal to the MDL. USGS defined Cd_mg_kg The cadmium concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 0.86 Milligrams per kilogram. Cd_QA Quality assurance flag for cadmium concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined U The measured concentration is less than the LOD. The reported concentration is equal to the MDL. USGS defined Ce_mg_kg The cerium concentration in sediment samples expressed in milligrams per kilogram of dry weight.. USGS Defined - 162.00 Milligrams per kilogram. Ce_QA Quality assurance flag for cerium concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Co_mg_kg The cobalt concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 130.00 Milligrams per kilogram. Co_QA Quality assurance flag for cobalt concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Cs_mg_kg The cesium concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 116.00 Milligrams per kilogram. Cs_QA Quality assurance flag for cesium concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined U The measured concentration is less than the LOD. The reported concentration is equal to the MDL. USGS defined Cu_mg_kg The copper concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 126.00 Milligrams per kilogram. Cu_QA Quality assurance flag for copper concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Ga_mg_kg The gallium concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 73.10 Milligrams per kilogram. Ga_QA Quality assurance flag for gallium concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined In_mg_kg Indium concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 2.91 Milligrams per kilogram. In_QA Quality assurance flag for indium concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined U The measured concentration is less than the LOD. The reported concentration is equal to the MDL. USGS defined La_mg_kg The lanthanum concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 75.31 Milligrams per kilogram. La_QA Quality assurance flag for lanthanum concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Li_mg_kg The lithium concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 62.92 Milligrams per kilogram. Li_QA Quality assurance flag for lithium concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Mn_mg_kg The manganese concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 1597.00 Milligrams per kilogram. Mn_QA Quality assurance flag for manganese concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Mo_mg_kg The molybdenum concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 1796.00 Milligrams per kilogram. Mo_QA Quality assurance flag for molybdenum concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Nb_mg_kg The niobium concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 17.60 Milligrams per kilogram. Nb_QA Quality assurance flag for niobium concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Ni_mg_kg The nickel concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 53.00 Milligrams per kilogram. Ni_QA Quality assurance flag for nickel concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined U The measured concentration is less than the LOD. The reported concentration is equal to the MDL. USGS defined P_mg_kg The phosphorous concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 3060.00 Milligrams per kilogram. P_QA Quality assurance flag for phosphorous concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Pb_mg_kg The lead concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 252.00 Milligrams per kilogram. Pb_QA Quality assurance flag for lead concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Rb_mg_kg The rubidium concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 128.00 Milligrams per kilogram. Rb_QA Quality assurance flag for rubidium concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Sb_mg_kg The antimony concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 5.78 Milligrams per kilogram. Sb_QA Quality assurance flag for antimony concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined U The measured concentration is less than the LOD. The reported concentration is equal to the MDL. USGS defined Sc_mg_kg The scandium concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 22.70 Milligrams per kilogram. Sc_QA Quality assurance flag for scandium concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Sn_mg_kg The tin concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 9.50 Milligrams per kilogram. Sn_QA Quality assurance flag for tin concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined U The measured concentration is less than the LOD. The reported concentration is equal to the MDL. USGS defined Sr_mg_kg The strontium concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 379.00 Milligrams per kilogram. Sr_QA Quality assurance flag for strontium concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Ta_mg_kg The tantalum concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 10.00 Milligrams per kilogram. Ta_QA Quality assurance flag for tantalum concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined U The measured concentration is less than the LOD. The reported concentration is equal to the MDL. USGS defined Te_mg_kg The tellurium concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 0.13 Milligrams per kilogram. Te_QA Quality assurance flag for tellurium concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined U The measured concentration is less than the LOD. The reported concentration is equal to the MDL. USGS defined - No qualifiers associated with the reported value. USGS defined Th_mg_kg The thorium concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 20.88 Milligrams per kilogram. Th_QA Quality assurance flag for thorium concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Tl_mg_kg The thallium concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 1.03 Milligrams per kilogram. Tl_QA Quality assurance flag for thallium concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined U The measured concentration is less than the LOD. The reported concentration is equal to the MDL. USGS defined U_mg_kg The uranium concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 4.04 Milligrams per kilogram. U_QA Quality assurance flag for uranium concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined V_mg_kg The vanadium concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 134.00 Milligrams per kilogram. V_QA Quality assurance flag for vanadium concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined W_mg_kg The tungsten concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 4.60 Milligrams per kilogram. W_QA Quality assurance flag for tungsten concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined Zn_mg_kg The zinc concentration in sediment samples expressed in milligrams per kilogram of dry weight. USGS Defined - 486 Milligrams per kilogram. Zn_QA Quality assurance flag for zinc concentrations. Values with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined NA The analysis was not performed due to the lack of sufficient sediment. USGS defined - No qualifiers associated with the reported value. USGS defined BackRiver_PCB_Data.csv Comma Separated Value (CSV) file containing PCB concentrations data in sediment samples for the study. USGS Defined Sample_ID The sample ID is a USGS generated unique sample identifier consisting of 3 letters (BRS) for Back River sediment and a unique 6-digit number. Suffixes designate the primary (.1) or secondary/duplicate (.2) sample of a location or sample. Additional suffixes designate field replicates as (.XR) and laboratory replicates of the sample as primary replicate (.X.1), as secondary replicate (.X.2) or as tertiary replicate (.X.3). Samples with suffixes (-10) and (-20) indicate the depth below land surface in centimeters from where that core sediment sample was collected. Quality control blank samples consist of the same naming scheme of 3 letters (BRS) with a different series (91XXXX) for equipment blanks and (93XXXX) for trip blanks as the unique 6-digit number. USGS Defined These are sample identifiers without scientific significance. Please refer to the attribute definition above for the naming convention details. Sample_Name The sample name indicates the origin of each sediment sample. Sample names begin with 2 letters (HR) for Herring Run and sequential numbers from 1-65 for land source samples and storm samples. Storm samples names include a descriptive suffix (PSS) indicating the use of a passive sampler and the storm event number. Core sample names begin with "Core" followed by a number for their location (1,3 or 4), and the depth below land surface in centimeters (CXX) from which the sample was acquired. Quality control blank sample names consist of the letters (EB) for equipment blank and (TB) for trip blank and the date they were collected in the following format -MMDDYYYY. USGS Defined These are sample identifiers indicating the origin of each sample. Please refer to the attribute definition above for the naming convention details. Sample_Date Date when the sample was collected from the site formatted as MM/DD/YYYY. USGS Defined 1/10/2023 12/13/2023 Sample_Type Sample source type USGS Defined Residential Sediment sample collected from the roadway storm drain closest to the randomly selected residential parcel. USGS defined Commercial Industrial Sediment sample collected from the roadway storm drain closets to the randomly selected commercial or industrial parcel. USGS defined Greenspace Composite sediment sample collected from vegetated or partially vegetated land. USGS defined Streambank city Composite sediment sample collected from eroded banks within Baltimore City. USGS defined Streambank county Composite sediment sample collected from eroded banks within Baltimore County. USGS defined Storm Suspended sediment sample from a storm event passive sampler. USGS defined Core Sediment collected from below land surface via advancing a tube by hand. USGS defined Equipment blank Quality control material(clean, baked sand) that should not contain any analytes processed identically to the samples. USGS defined Trip blank Quality control material(clean, baked sand) that should not contain any analytes processed identically to the samples. USGS defined Latitude Coordinate that specifies the north-south position of the sample point on the surface of the Earth. USGS Defined NA No Data USGS defined 38.335193 39.400466 Decimal degrees Longitude Coordinate that specifies the east-west position of the sample point on the surface of the Earth. USGS Defined NA No Data USGS defined -76.610001 -76.498249 Decimal degrees PCB_Conc_Units PCB concentration units are in nanograms per gram of dry weight. USGS Defined Nanogram per gram of dry weight. PCB_1_Conc PCB congener 1; 2-Chlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 1.99541 2.017145 Nanograms per gram of dry weight. PCB_1_QA Quality assurance flag for PCB congener 1; 2-Chlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_3_Conc PCB congener 3; 4-Chlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 1.164322 1.177004 Nanograms per gram of dry weight. PCB_3_QA Quality assurance flag for PCB congener 3; 4-Chlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_4_10_Conc PCB congeners 4 and 10; 2,2'-Dichlorobiphenyl and 2,6-Dichlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.565399 0.571558 Nanograms per gram of dry weight. PCB_4_10_QA Quality assurance flag for PCB congeners 4 and 10; 2,2'-Dichlorobiphenyl and 2,6-Dichlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_7_9_Conc PCB congeners 7 and 9; 2,4-Dichlorobiphenyl and 2,5-Dichlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.199541 0.201714 Nanograms per gram of dry weight. PCB_7_9_QA Quality assurance flag for PCB congeners 7 and 9; 2,4-Dichlorobiphenyl and 2,5-Dichlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_6_Conc PCB congener 6; 2,3'-Dichlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.315973 0.319415 Nanograms per gram of dry weight. PCB_6_QA Quality assurance flag for PCB congener 6; 2,3'-Dichlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_8_5_Conc PCB congeners 8 and 5; 2,4'-Dichlorobiphenyl and 2,3-Dichlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 2.327646 2.353 Nanograms per gram of dry weight. PCB_8_5_QA Quality assurance flag for PCB congeners 8 and 5; 2,4'-Dichlorobiphenyl and 2,3-Dichlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_19_Conc PCB congener 19;2,2',6-Trichlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.046562 0.04707 Nanograms per gram of dry weight. PCB_19_QA Quality assurance flag for PCB congener 19;2,2',6-Trichlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_12_13_Conc PCB congeners 12 and 13; 3,4-Dichlorobiphenyl and 3,4'-Dichlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.044397 0.044881 Nanograms per gram of dry weight. PCB_12_13_QA Quality assurance flag for PCB congeners 12 and 13; 3,4-Dichlorobiphenyl and 3,4'-Dichlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_18_Conc PCB congener 18; 2,2',5-Trichlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.615284 0.621986 Nanograms per gram of dry weight. PCB_18_QA Quality assurance flag for PCB congener 18; 2,2',5-Trichlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_17_15_Conc PCB congeners 17 and 15; 2,2',4-Trichlorobiphenyl and 4,4'-Dichlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.615284 0.621986 Nanograms per gram of dry weight. PCB_17_15_QA Quality assurance flag for PCB congeners 17 and 15; 2,2',4-Trichlorobiphenyl and 4,4'-Dichlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_24_27_Conc PCB congeners 24 and 27; 2,3,6-Trichlorobiphenyl and 2,3',6-Trichlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.04323 0.043701 Nanograms per gram of dry weight. PCB_24_27_QA Quality assurance flag for PCB congeners 24 and 27; 2,3,6-Trichlorobiphenyl and 2,3',6-Trichlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_16_32_Conc PCB congeners 16 and 32; 2,2',3-Trichlorobiphenyl and 2,4',6-Trichlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.648508 0.655572 Nanograms per gram of dry weight. PCB_16_32_QA Quality assurance flag for PCB congeners 16 and 32; 2,2',3-Trichlorobiphenyl and 2,4',6-Trichlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_26_Conc PCB congener 26; 2,3',5-Trichlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.119724 0.121028 Nanograms per gram of dry weight. PCB_26_QA Quality assurance flag for PCB congener 26; 2,3',5-Trichlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined - No qualifiers are associated with the reported concentration. USGS defined PCB_25_Conc PCB congener 25; 2,3',4-Trichlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.053207 0.102521 Nanograms per gram of dry weight. PCB_25_QA Quality assurance flag for PCB congener 25; 2,3',4-Trichlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined - No qualifiers are associated with the reported concentration. USGS defined PCB_31_Conc PCB congener 31; 2,4',5-Trichlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.864711 0.87413 Nanograms per gram of dry weight. PCB_31_QA Quality assurance flag for PCB congener 31; 2,4',5-Trichlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_28_Conc PCB congener 28; 2,4,4'-Trichlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.698393 0.706001 Nanograms per gram of dry weight. PCB_28_QA Quality assurance flag for PCB congener 28; 2,4,4'-Trichlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_21_33_53_Conc PCB congeners 21, 33 and 53; 2,3,4-Trichlorobiphenyl, 2,3',4'-Trichlorobiphenyl and 2,2',5,6'-Tetrachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.548737 0.554715 Nanograms per gram of dry weight. PCB_21_33_53_QA Quality assurance flag for PCB congeners 21, 33 and 53; 2,3,4-Trichlorobiphenyl, 2,3',4'-Trichlorobiphenyl and 2,2',5,6'-Tetrachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_51_Conc PCB congener 51; 2,2',4,6'-Tetrachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.029931 0.115023 Nanograms per gram of dry weight. PCB_51_QA Quality assurance flag for PCB congener 51; 2,2',4,6'-Tetrachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined - No qualifiers are associated with the reported concentration. USGS defined PCB_22_Conc PCB congener 22; 2,3,4'-Trichlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.48219 0.487443 Nanograms per gram of dry weight. PCB_22_QA Quality assurance flag for PCB congener 22; 2,3,4'-Trichlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_45_Conc PCB congener 45; 2,2',3,6-Tetrachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.147959 0.149571 Nanograms per gram of dry weight. PCB_45_QA Quality assurance flag for PCB congener 45; 2,2',3,6-Tetrachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_46_Conc PCB congener 46; 2,2',3,6'-Tetrachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.066517 0.076515 Nanograms per gram of dry weight. PCB_46_QA Quality assurance flag for PCB congener 46; 2,2',3,6'-Tetrachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined - No qualifiers are associated with the reported concentration. USGS defined PCB_52_43_Conc PCB congeners 52 and 43; 2,2',5,5'-Tetrachlorobiphenyl and 2,2',3,5-Tetrachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.781502 2.235852 Nanograms per gram of dry weight. PCB_52_43_QA Quality assurance flag for PCB congeners 52 and 43; 2,2',5,5'-Tetrachlorobiphenyl and 2,2',3,5-Tetrachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_49_Conc PCB congener 49; 2,2',4,5'-Tetrachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.38242 0.70204 Nanograms per gram of dry weight. PCB_49_QA Quality assurance flag for PCB congener 49; 2,2',4,5'-Tetrachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined - No qualifiers are associated with the reported concentration. USGS defined PCB_47_Conc PCB congener 47; 2,2',4,4'-Tetrachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.166317 0.541908 Nanograms per gram of dry weight. PCB_47_QA Quality assurance flag for PCB congener 47; 2,2',4,4'-Tetrachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined - No qualifiers are associated with the reported concentration. USGS defined PCB_48_Conc PCB congener 48; 2,2',4,5-Tetrachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.166317 0.168129 Nanograms per gram of dry weight. PCB_48_QA Quality assurance flag for PCB congener 48; 2,2',4,5-Tetrachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_44_Conc PCB congener 44; 2,2',3,5'-Tetrachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.715055 1.119176 Nanograms per gram of dry weight. PCB_44_QA Quality assurance flag for PCB congener 44; 2,2',3,5'-Tetrachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined - No qualifiers are associated with the reported concentration. USGS defined PCB_37_Conc PCB congener 37; 3,4,4'-Trichlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.199541 0.201714 Nanograms per gram of dry weight. PCB_37_QA Quality assurance flag for PCB congener 37; 3,4,4'-Trichlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined - No qualifiers are associated with the reported concentration. USGS defined PCB_42_Conc PCB congener 42; 2,2',3,4'-Tetrachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.232764 0.291258 Nanograms per gram of dry weight. PCB_42_QA Quality assurance flag for PCB congener 42; 2,2',3,4'-Tetrachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined - No qualifiers are associated with the reported concentration. USGS defined PCB_41_71_Conc PCB congeners 41 and 71; 2,2',3,4-Tetrachlorobiphenyl and 2,3',4',6-Tetrachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.38242 0.555911 Nanograms per gram of dry weight. PCB_41_71_QA Quality assurance flag for PCB congeners 41 and 71; 2,2',3,4-Tetrachlorobiphenyl and 2,3',4',6-Tetrachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined - No qualifiers are associated with the reported concentration. USGS defined PCB_64_Conc PCB congener 64; 2,3,4',6-Tetrachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.299311 0.396337 Nanograms per gram of dry weight. PCB_64_QA Quality assurance flag for PCB congener 64; 2,3,4',6-Tetrachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined - No qualifiers are associated with the reported concentration. USGS defined PCB_40_Conc PCB congener 40; 2,2',3,3'-Tetrachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.15634 0.158043 Nanograms per gram of dry weight. PCB_40_QA Quality assurance flag for PCB congener 40; 2,2',3,3'-Tetrachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_100_Conc PCB congener 100; 2,2',4,4',6-Pentachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.036585 0.754322 Nanograms per gram of dry weight. PCB_100_QA Quality assurance flag for PCB congener 100; 2,2',4,4',6-Pentachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_63_Conc PCB congener 63; 2,3,4',5-Tetrachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.034919 0.043708 Nanograms per gram of dry weight. PCB_63_QA Quality assurance flag for PCB congener 63; 2,3,4',5-Tetrachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined - No qualifiers are associated with the reported concentration. USGS defined PCB_74_Conc PCB congener 74; 2,4,4',5-Tetrachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.315973 0.422015 Nanograms per gram of dry weight. PCB_74_QA Quality assurance flag for PCB congener 74; 2,4,4',5-Tetrachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined - No qualifiers are associated with the reported concentration. USGS defined PCB_70_76_Conc PCB congeners 70 and 76; 2,3',4',5-Tetrachlorobiphenyl and 2,3',4',5'-Tetrachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.565399 1.850329 Nanograms per gram of dry weight. PCB_70_76_QA Quality assurance flag for PCB congeners 70 and 76; 2,3',4',5-Tetrachlorobiphenyl and 2,3',4',5'-Tetrachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_66_95_Conc PCB congeners 66 and 95; 2,3',4,4'-Tetrachlorobiphenyl and 2,2',3,5',6-Pentachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 1.197246 1.528005 Nanograms per gram of dry weight. PCB_66_95_QA Quality assurance flag for PCB congeners 66 and 95; 2,3',4,4'-Tetrachlorobiphenyl and 2,2',3,5',6-Pentachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined - No qualifiers are associated with the reported concentration. USGS defined PCB_91_Conc PCB congener 91; 2,2',3,4',6-Pentachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.084804 1.34523 Nanograms per gram of dry weight. PCB_91_QA Quality assurance flag for PCB congener 91; 2,2',3,4',6-Pentachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_56_60_Conc PCB congeners 56 and 60; 2,3,3',4'-Tetrachlorobiphenyl and 2,3,4,4'-Tetrachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.581961 0.61797 Nanograms per gram of dry weight. PCB_56_60_QA Quality assurance flag for PCB congeners 56 and 60; 2,3,3',4'-Tetrachlorobiphenyl and 2,3,4,4'-Tetrachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined - No qualifiers are associated with the reported concentration. USGS defined PCB_101_92_84_89_Conc PCB congeners 101, 92, 84 and 89;2,2',4,5,5'-Pentachlorobiphenyl, 2,2',3,5,5'-Pentachlorobiphenyl, 2,2',3,3',6-Pentachlorobiphenyl and 2,2',3,4,6'-Pentachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.615284 19.800939 Nanograms per gram of dry weight. PCB_101_92_84_89_QA Quality assurance flag for PCB congeners 101, 92, 84 and 89;2,2',4,5,5'-Pentachlorobiphenyl, 2,2',3,5,5'-Pentachlorobiphenyl, 2,2',3,3',6-Pentachlorobiphenyl and 2,2',3,4,6'-Pentachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_99_Conc PCB congener 99; 2,2',4,4',5-Pentachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.123017 3.29884 Nanograms per gram of dry weight. PCB_99_QA Quality assurance flag for PCB congener 99; 2,2',4,4',5-Pentachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_83_Conc PCB congener 83; 2,2',3,3',5-Pentachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.024942 0.664367 Nanograms per gram of dry weight. PCB_83_QA Quality assurance flag for PCB congener 83; 2,2',3,3',5-Pentachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_97_Conc PCB congener 97; 2,2',3,4',5'-Pentachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.093115 2.863127 Nanograms per gram of dry weight. PCB_97_QA Quality assurance flag for PCB congener 97; 2,2',3,4',5'-Pentachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_81_87_Conc PCB congeners 81 and 87; 3,4,4',5-Tetrachlorobiphenyl and 2,2',3,4,5'-Pentachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.192856 7.357828 Nanograms per gram of dry weight. PCB_81_87_QA Quality assurance flag for PCB congeners 81 and 87; 3,4,4',5-Tetrachlorobiphenyl and 2,2',3,4,5'-Pentachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined - No qualifiers are associated with the reported concentration. USGS defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_85_Conc PCB congener 85; 2,2',3,4,4'-Pentachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.116432 2.380323 Nanograms per gram of dry weight. PCB_85_QA Quality assurance flag for PCB congener 85; 2,2',3,4,4'-Pentachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined - No qualifiers are associated with the reported concentration. USGS defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_136_Conc PCB congener 136; 2,2',3,3',6,6'-Hexachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.124713 1.369626 Nanograms per gram of dry weight. PCB_136_QA Quality assurance flag for PCB congener 136; 2,2',3,3',6,6'-Hexachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_110_77_Conc PCB congeners 110 and 77; 2,3,3',4',6-Pentachlorobiphenyl and 3,3',4,4'-Tetrachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.349196 17.874525 Nanograms per gram of dry weight. PCB_110_77_QA Quality assurance flag for PCB congeners 110 and 77; 2,3,3',4',6-Pentachlorobiphenyl and 3,3',4,4'-Tetrachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined - No qualifiers are associated with the reported concentration. USGS defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_82_151_Conc PCB congeners 82 and 151; 2,2',3,3',4-Pentachlorobiphenyl and 2,2',3,5,5',6-Hexachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.349196 2.740151 Nanograms per gram of dry weight. PCB_82_151_QA Quality assurance flag for PCB congeners 82 and 151; 2,2',3,3',4-Pentachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_135_144_Conc PCB congeners 135 and 144; 2,2',3,3',5,6'-Hexachlorobiphenyl and 2,2',3,4,5',6-Hexachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.147959 2.111277 Nanograms per gram of dry weight. PCB_135_144_QA Quality assurance flag for PCB congeners 135 and 144; 2,2',3,3',5,6'-Hexachlorobiphenyl and 2,2',3,4,5',6-Hexachlorobipheny. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_107_Conc PCB congener 107; 2,3,3',4',5-Pentachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.02162 0.924615 Nanograms per gram of dry weight. PCB_107_QA Quality assurance flag for PCB congener 107; 2,3,3',4',5-Pentachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined - No qualifiers are associated with the reported concentration. USGS defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_149_123_Conc PCB congeners 149 and 123; 2,2',3,4',5',6-Hexachlorobiphenyl and 2,3',4,4',5'-Pentachlorobiphenyl combined concentrations expressed in nanograms per gram of dry weight. USGS Defined 0.465629 6.04829 Nanograms per gram of dry weight. PCB_149_123_QA Quality assurance flag for PCB congener 149 and 123; 2,2',3,4',5',6-Hexachlorobiphenyl and 2,3',4,4',5'-Pentachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_118_Conc PCB congener 118; 2,3',4,4',5-Pentachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.199541 11.194161 Nanograms per gram of dry weight. PCB_118_QA Quality assurance flag for PCB congener 118; 2,3',4,4',5-Pentachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined - No qualifiers are associated with the reported concentration. USGS defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_134_Conc PCB congener 134; 2,2',3,3',5,6-Hexachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.011972 0.660267 Nanograms per gram of dry weight. PCB_134_QA Quality assurance flag for PCB congener 134; 2,2',3,3',5,6-Hexachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_114_131_Conc PCB congeners 114 and 131; 2,3,4,4',5-Pentachlorobiphenyl and 2,2',3,3',4,6-Hexachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.046562 1.901219 Nanograms per gram of dry weight. PCB_114_131_QA Quality assurance flag for PCB congeners 114 and 131; 2,3,4,4',5-Pentachlorobiphenyl and 2,2',3,3',4,6-Hexachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_146_Conc PCB congener 146; 2,2',3,4',5,5'-Hexachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.06485 1.652969 Nanograms per gram of dry weight. PCB_146_QA Quality assurance flag for PCB congener 146; 2,2',3,4',5,5'-Hexachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined - No qualifiers are associated with the reported concentration. USGS defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_153_Conc PCB congener 153; 2,2',4,4',5,5'-Hexachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.448967 6.377324 Nanograms per gram of dry weight. PCB_153_QA Quality assurance flag for PCB congener 153; 2,2',4,4',5,5'-Hexachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_132_Conc PCB congener 132; 2,2',3,3',4,6'-Hexachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.103062 5.151569 Nanograms per gram of dry weight. PCB_132_QA Quality assurance flag for PCB congener 132; 2,2',3,3',4,6'-Hexachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_105_Conc PCB congener 105; 2,3,3',4,4'-Pentachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.018287 0.728954 Nanograms per gram of dry weight. PCB_105_QA Quality assurance flag for PCB congener 105; 2,3,3',4,4'-Pentachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined - No qualifiers are associated with the reported concentration. USGS defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_141_Conc PCB congener 141; 2,2',3,4,5,5'-Hexachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.282649 3.984503 Nanograms per gram of dry weight. PCB_141_QA Quality assurance flag for PCB congener 141; 2,2',3,4,5,5'-Hexachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined - No qualifiers are associated with the reported concentration. USGS defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_176_130_137_Conc PCB congeners 176,130 and 137; 2,2',3,3',4,6,6'-Heptachlorobiphenyl, 2,2',3,3',4,5'-Hexachlorobiphenyl and 2,2',3,4,4',5-Hexachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.055871 0.636772 Nanograms per gram of dry weight. PCB_176_130_137_QA Quality assurance flag for PCB congener 176,130 and 137; 2,2',3,3',4,6,6'-Heptachlorobiphenyl, 2,2',3,3',4,5'-Hexachlorobiphenyl and 2,2',3,4,4',5-Hexachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_163_138_Conc PCB congeners 163 and 138; 2,3,3',4',5,6-Hexachlorobiphenyl and 2,2',3,4,4',5'-Hexachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.448967 18.020595 Nanograms per gram of dry weight. PCB_163_138_QA Quality assurance flag for PCB congeners 163 and 138; 2,3,3',4',5,6-Hexachlorobiphenyl and 2,2',3,4,4',5'-Hexachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined - No qualifiers are associated with the reported concentration. USGS defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_158_Conc PCB congener 158; 2,3,3',4,4',6-Hexachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.041574 2.600879 Nanograms per gram of dry weight. PCB_158_QA Quality assurance flag for PCB congener 158; 2,3,3',4,4',6-Hexachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined - No qualifiers are associated with the reported concentration. USGS defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_178_129_Conc PCB congener 178 and 129; 2,2',3,3',5,5',6-Heptachlorobiphenyl and 2,2',3,3',4,5-Hexachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.182879 1.794641 Nanograms per gram of dry weight. PCB_178_129_QA Quality assurance flag for PCB congeners 178 and 129; 2,2',3,3',5,5',6-Heptachlorobiphenyl and 2,2',3,3',4,5-Hexachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_175_Conc PCB congener 175; 2,2',3,3'4,5',6-Heptachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.033253 0.187318 Nanograms per gram of dry weight. PCB_175_QA Quality assurance flag for PCB congener 175; 2,2',3,3'4,5',6-Heptachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_187_182_Conc PCB congeners 187 and 182; 2,2',3,4',5,5',6-Heptachlorobiphenyl and 2,2',3,4,4',5,6'-Heptachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.598623 2.410041 Nanograms per gram of dry weight. PCB_187_182_QA Quality assurance flag for PCB congeners 187 and 182; 2,2',3,4',5,5',6-Heptachlorobiphenyl and 2,2',3,4,4',5,6'-Heptachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_183_Conc PCB congener 183; 2,2',3,4,4',5',6-Heptachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.282649 1.575057 Nanograms per gram of dry weight. PCB_183_QA Quality assurance flag for PCB congener 183; 2,2',3,4,4',5',6-Heptachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_128_Conc PCB congener 128; 2,2',3,3',4,4'-Hexachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.016631 3.105578 Nanograms per gram of dry weight. PCB_128_QA Quality assurance flag for PCB congener 128; 2,2',3,3',4,4'-Hexachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined - No qualifiers are associated with the reported concentration. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined PCB_185_Conc PCB congener 185; 2,2',3,4,5,5',6-Heptachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.07815 0.296329 Nanograms per gram of dry weight. PCB_185_QA Quality assurance flag for PCB congener 185; 2,2',3,4,5,5',6-Heptachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_174_Conc PCB congener 174; 2,2',3,3',4,5,6'-Heptachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.532076 2.717471 Nanograms per gram of dry weight. PCB_174_QA Quality assurance flag for PCB congener 174; 2,2',3,3',4,5,6'-Heptachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_177_Conc PCB congener 177; 2,2',3,3',4,5',6'-Heptachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.282649 1.828782 Nanograms per gram of dry weight. PCB_177_QA Quality assurance flag for PCB congener 177; 2,2',3,3',4,5',6'-Heptachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_202_171_156_Conc PCB congeners 202, 171 and 156; 2,2',3,3',5,5',6,6'-Octachlorobiphenyl, 2,2',3,3',4,4',6-Heptachlorobiphenyl and 2,3,3',4,4',5-Hexachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.141374 0.692838 Nanograms per gram of dry weight. PCB_202_171_156_QA Quality assurance flag for PCB congeners 202, 171 and 156; 2,2',3,3',5,5',6,6'-Octachlorobiphenyl, 2,2',3,3',4,4',6-Heptachlorobiphenyl and 2,3,3',4,4',5-Hexachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_157_200_Conc PCB congeners 157 and 200; 2,3,3',4,4',5'-Hexachlorobiphenyl and 2,2',3,3',4,5,6,6'-Octachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.129701 0.632273 Nanograms per gram of dry weight. PCB_157_200_QA Quality assurance flag for PCB congeners 157 and 200; 2,3,3',4,4',5'-Hexachlorobiphenyl and 2,2',3,3',4,5,6,6'-Octachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_172_197_Conc PCB congeners 172 and 197; 2,2',3,3',4,5,5'-Heptachlorobiphenyl and 2,2',3,3',4,4',6,6'-Octachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.111443 0.993598 Nanograms per gram of dry weight. PCB_172_197_QA Quality assurance flag for PCB congeners 172 and 197; 2,2',3,3',4,5,5'-Heptachlorobiphenyl and 2,2',3,3',4,4',6,6'-Octachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_180_Conc PCB congener 180; 2,2',3,4,4',5,5'-Heptachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 1.014666 6.484848 Nanograms per gram of dry weight. PCB_180_QA Quality assurance flag for PCB congener 180; 2,2',3,4,4',5,5'-Heptachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_193_Conc PCB congener 193; 2,3,3',4',5,5',6-Heptachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.069839 0.470447 Nanograms per gram of dry weight. PCB_193_QA Quality assurance flag for PCB congener 193; 2,3,3',4',5,5',6-Heptachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined - No qualifiers are associated with the reported concentration. USGS defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_191_Conc PCB congener 191; 2,3,3',4,4',5',6-Heptachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.019954 0.20662 Nanograms per gram of dry weight. PCB_191_QA Quality assurance flag for PCB congener 191; 2,3,3',4,4',5',6-Heptachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_199_Conc PCB congener 199; 2,2',3,3',4,5,5',6'-Octachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.071505 0.221344 Nanograms per gram of dry weight. PCB_199_QA Quality assurance flag for PCB congener 199; 2,2',3,3',4,5,5',6'-Octachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined - No qualifiers are associated with the reported concentration. USGS defined PCB_170_190_Conc PCB congeners 170 and 190; 2,2',3,3',4,4',5-Heptachlorobiphenyl and 2,3,3',4,4',5,6-Heptachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.282649 3.064806 Nanograms per gram of dry weight. PCB_170_190_QA Quality assurance flag for PCB congeners 170 and 190; 2,2',3,3',4,4',5-Heptachlorobiphenyl and 2,3,3',4,4',5,6-Heptachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_198_Conc PCB congener 198; 2,2',3,3',4,5,5',6-Octachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.019954 0.081816 Nanograms per gram of dry weight. PCB_198_QA Quality assurance flag for PCB congener 198; 2,2',3,3',4,5,5',6-Octachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_201_Conc PCB congener 201; 2,2',3,3',4,5',6,6'-Octachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.698393 3.280656 Nanograms per gram of dry weight. PCB_201_QA Quality assurance flag for PCB congener 201; 2,2',3,3',4,5',6,6'-Octachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_203_196_Conc PCB congeners 203 and 196; 2,2',3,4,4',5,5',6-Octachlorobiphenyl and 2,2',3,3',4,4',5,6'-Octachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.715055 3.198839 Nanograms per gram of dry weight. PCB_203_196_QA Quality assurance flag for PCB congeners 203 and 196; 2,2',3,4,4',5,5',6-Octachlorobiphenyl and 2,2',3,3',4,4',5,6'-Octachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_208_195_Conc PCB congeners 208 and 195; 2,2',3,3',4,5,5',6,6'-Nonachlorobiphenyl and 2,2',3,3',4,4',5,6-Octachlorobiphenyl combined concentration expressed in nanograms per gram of dry weight. USGS Defined 0.132994 2.215674 Nanograms per gram of dry weight. PCB_208_195_QA Quality assurance flag for PCB congeners 208 and 195; 2,2',3,3',4,5,5',6,6'-Nonachlorobiphenyl and 2,2',3,3',4,4',5,6-Octachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_207_Conc PCB congener 207; 2,2',3,3',4,4',5,6,6'-Nonachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.014965 0.237221 Nanograms per gram of dry weight. PCB_207_QA Quality assurance flag for PCB congener 207; 2,2',3,3',4,4',5,6,6'-Nonachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_194_Conc PCB congener 194; 2,2',3,3',4,4',5,5'-Octachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.299311 1.337067 Nanograms per gram of dry weight. PCB_194_QA Quality assurance flag for PCB congener 194; 2,2',3,3',4,4',5,5'-Octachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_205_Conc PCB congener 205; 2,3,3',4,4',5,5',6-Octachlorobipheny concentration expressed in nanograms per gram of dry weight. USGS Defined 0.018287 0.10262 Nanograms per gram of dry weight. PCB_205_QA Quality assurance flag for PCB congener 205; 2,3,3',4,4',5,5',6-Octachlorobipheny. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_206_Conc PCB congener 206; 2,2',3,3',4,4',5,5',6-Nonachlorobiphenyl oncentration expressed in nanograms per gram of dry weight. USGS Defined 0.11304 3.657747 Nanograms per gram of dry weight. PCB_206_QA Quality assurance flag for PCB congener 206; 2,2',3,3',4,4',5,5',6-Nonachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined - No qualifiers are associated with the reported concentration. USGS defined US U:The measured value is below the calibration limit and the reported value is the LOQ for the sample. S : The surrogate recovery is < 70% and the value may be biased low. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined PCB_209_Conc PCB congener 209; Decachlorobiphenyl concentration expressed in nanograms per gram of dry weight. USGS Defined 0.001995 8.642914 Nanograms per gram of dry weight. PCB_209_QA Quality assurance flag for PCB congener 209; Decachlorobiphenyl. Concentrations associated with a qualifier will have one or more letter codes in this field. The absence of qualifiers is also noted. USGS Defined - No qualifiers are associated with the reported concentration. USGS defined U The measured value is below the calibration limit and the reported value is the LOQ for the sample. USGS defined S The surrogate recovery is < 70% and the value may be biased low. USGS defined E The measured value is above calibration limit and the reported value is estimated. USGS defined BackRiver_PCB_Bioavailability_Data.csv Comma Separated Value (CSV) file containing data for PCB calculated concentrations in porewater from sediment concentrations using equilibrium partitioning (Booij, 2003)for select storm and core sediment samples collected in the study. USGS Defined Sample_ID USGS generated unique sample identifier consisting of 3 letters (BRS) for Back River sediment and a unique 6-digit number. Suffixes designate the primary (.1) or secondary/duplicate (.2) sample of a location or sample. Additional suffixes designate field replicates as (.XR) and laboratory replicates of the sample as primary replicate (.X.1), or as secondary replicate (.X.2). Samples with suffixes (-10) and (-20) indicate the depth below land surface in centimeters from where that core sediment sample was collected. USGS Defined These are sample identifiers without scientific significance. Please refer to the attribute definition above for the naming convention details. Sample_Name The sample name indicates the origin of each sediment sample. Sample names begin with 2 letters (HR) for Herring Run and sequential numbers from 1-65 for land source samples and storm samples. Storm samples names include a descriptive suffix (PSS) indicating the use of a passive sampler and the storm event number. Core sample names begin with "Core" followed by a number for their location (1,3 or 4), and the depth below land surface in centimeters (CXX) from which the sample was acquired. USGS Defined These are sample identifiers indicating the origin of each sample. Please refer to the attribute definition above for the naming convention details. Sample_Date Date when the sample was collected from the site formatted as MM/DD/YYYY. USGS Defined 10/23/2023 7/5/2023 Sample_Type Sample source type USGS Defined Storm Suspended sediment sample from a storm event passive sampler. USGS defined Core Sediment collected from below land surface via advancing a tube by hand. USGS defined Latitude Coordinate that specifies the north-south position of the sample point on the surface of the Earth. USGS Defined 39.302959 39.318061 Decimal Degrees Longitude Coordinate that specifies the east-west position of the sample point on the surface of the Earth. USGS Defined -76.555271 -76.498249 Decimal Degrees Calc_Conc_Units PCB calculated concentration units are in nanograms per liter. USGS Defined PCB calculated concentration units are in nanograms per liter. Foc Fraction of organic carbon USGS Defined 0.00807 0.13047 Fraction of organic carbon PCB_1_CalcConc PCB congener 1; 2-Chlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.213089 3.443018 Nanograms per liter PCB_3_CalcConc PCB congener 3; 4-Chlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.07518 1.214731 Nanograms per liter PCB_4_10_CalcConc PCB congeners 4 and 10; 2,2'-Dichlorobiphenyl and 2,6-Dichlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.039846 0.643817 Nanograms per liter PCB_7_9_CalcConc PCB congeners 7 and 9; 2,4-Dichlorobiphenyl and 2,5-Dichlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.005611 0.090664 Nanograms per liter PCB_6_CalcConc PCB congener 6; 2,3'-Dichlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.009081 0.146743 Nanograms per liter PCB_8_5_CalcConc PCB congeners 8 and 5; 2,4'-Dichlorobiphenyl and 2,3-Dichlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.065455 1.057606 Nanograms per liter PCB_19_CalcConc PCB congener 19;2,2',6-Trichlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.00146 0.023601 Nanograms per liter PCB_12_13_CalcConc PCB congeners 12 and 13; 3,4-Dichlorobiphenyl and 3,4'-Dichlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.000899 0.01453 Nanograms per liter PCB_18_CalcConc PCB congener 18; 2,2',5-Trichlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.011929 0.192745 Nanograms per liter PCB_17_15_CalcConc PCB congeners 17 and 15; 2,2',4-Trichlorobiphenyl and 4,4'-Dichlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.010461 0.169037 Nanograms per liter PCB_24_27_CalcConc PCB congeners 24 and 27; 2,3,6-Trichlorobiphenyl and 2,3',6-Trichlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.000658 0.010646 Nanograms per liter PCB_16_32_CalcConc PCB congeners 16 and 32; 2,2',3-Trichlorobiphenyl and 2,4',6-Trichlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.014977 0.242004 Nanograms per liter PCB_26_CalcConc PCB congener 26; 2,3',5-Trichlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000926 0.014965 Nanograms per liter PCB_25_CalcConc PCB congener 25; 2,3',4-Trichlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000402 0.006507 Nanograms per liter PCB_31_CalcConc PCB congener 31; 2,4',5-Trichlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.006544 0.105749 Nanograms per liter PCB_28_CalcConc PCB congener 28; 2,4,4'-Trichlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.005286 0.085409 Nanograms per liter PCB_21_33_53_CalcConc PCB congeners 21, 33 and 53; 2,3,4-Trichlorobiphenyl, 2,3',4'-Trichlorobiphenyl and 2,2',5,6'-Tetrachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.005893 0.095229 Nanograms per liter PCB_51_CalcConc PCB congener 51; 2,2',4,6'-Tetrachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000247 0.006312 Nanograms per liter PCB_22_CalcConc PCB congener 22; 2,3,4'-Trichlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.004443 0.0718 Nanograms per liter PCB_45_CalcConc PCB congener 45; 2,2',3,6-Tetrachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.001521 0.024578 Nanograms per liter PCB_46_CalcConc PCB congener 46; 2,2',3,6'-Tetrachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000683 0.011049 Nanograms per liter PCB_52_43_CalcConc PCB congeners 52 and 43; 2,2',5,5'-Tetrachlorobiphenyl and 2,2',3,5-Tetrachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.004078 0.065892 Nanograms per liter PCB_49_CalcConc PCB congener 49; 2,2',4,5'-Tetrachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.001952 0.031546 Nanograms per liter PCB_47_CalcConc PCB congener 47; 2,2',4,4'-Tetrachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000849 0.016904 Nanograms per liter PCB_48_CalcConc PCB congener 48; 2,2',4,5-Tetrachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000989 0.015989 Nanograms per liter PCB_44_CalcConc PCB congener 44; 2,2',3,5'-Tetrachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.004543 0.073408 Nanograms per liter PCB_37_CalcConc PCB congener 37; 3,4,4'-Trichlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.001064 0.017196 Nanograms per liter PCB_42_CalcConc PCB congener 42; 2,2',3,4'-Tetrachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.001446 0.023378 Nanograms per liter PCB_41_71_CalcConc PCB congeners 41 and 71; 2,2',3,4-Tetrachlorobiphenyl and 2,3',4',6-Tetrachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.00277 0.044765 Nanograms per liter PCB_64_CalcConc PCB congener 64; 2,3,4',6-Tetrachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.001227 0.019839 Nanograms per liter PCB_40_CalcConc PCB congener 40; 2,2',3,3'-Tetrachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.001209 0.019542 Nanograms per liter PCB_100_CalcConc PCB congener 100; 2,2',4,4',6-Pentachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000128 0.027051 Nanograms per liter PCB_63_CalcConc PCB congener 63; 2,3,4',5-Tetrachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 8.8e-05 0.00143 Nanograms per liter PCB_74_CalcConc PCB congener 74; 2,4,4',5-Tetrachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.00075 0.012121 Nanograms per liter PCB_70_76_CalcConc PCB congeners 70 and 76; 2,3',4',5-Tetrachlorobiphenyl and 2,3',4',5'-Tetrachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.001342 0.02169 Nanograms per liter PCB_66_95_CalcConc PCB congeners 66 and 95; 2,3',4,4'-Tetrachlorobiphenyl and 2,2',3,5',6-Pentachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.002842 0.045929 Nanograms per liter PCB_91_CalcConc PCB congener 91; 2,2',3,4',6-Pentachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000613 0.010161 Nanograms per liter PCB_56_60_CalcConc PCB congeners 56 and 60; 2,3,3',4'-Tetrachlorobiphenyl and 2,3,4,4'-Tetrachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.001682 0.027183 Nanograms per liter PCB_101_92_84_89_CalcConc PCB congeners 101, 92, 84 and 89;2,2',4,5,5'-Pentachlorobiphenyl, 2,2',3,5,5'-Pentachlorobiphenyl, 2,2',3,3',6-Pentachlorobiphenyl and 2,2',3,4,6'-Pentachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.00398 0.062963 Nanograms per liter PCB_99_CalcConc PCB congener 99; 2,2',4,4',5-Pentachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000767 0.009931 Nanograms per liter PCB_83_CalcConc PCB congener 83; 2,2',3,3',5-Pentachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000165 0.002658 Nanograms per liter PCB_97_CalcConc PCB congener 97; 2,2',3,4',5'-Pentachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000586 0.010727 Nanograms per liter PCB_81_87_CalcConc PCB congeners 81 and 87; 3,4,4',5-Tetrachlorobiphenyl and 2,2',3,4,5'-Pentachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.001327 0.023653 Nanograms per liter PCB_85_CalcConc PCB congener 85; 2,2',3,4,4'-Pentachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000661 0.008725 Nanograms per liter PCB_136_CalcConc PCB congener 136; 2,2',3,3',6,6'-Hexachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000571 0.006704 Nanograms per liter PCB_110_77_CalcConc PCB congeners 110 and 77; 2,3,3',4',6-Pentachlorobiphenyl and 3,3',4,4'-Tetrachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.003607 0.057463 Nanograms per liter PCB_82_151_CalcConc PCB congeners 82 and 151; 2,2',3,3',4-Pentachlorobiphenyl and 2,2',3,5,5',6-Hexachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.001182 0.013396 Nanograms per liter PCB_135_144_CalcConc PCB congeners 135 and 144; 2,2',3,3',5,6'-Hexachlorobiphenyl and 2,2',3,4,5',6-Hexachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.000378 0.003904 Nanograms per liter PCB_107_CalcConc PCB congener 107; 2,3,3',4',5-Pentachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.0001 0.001382 Nanograms per liter PCB_149_123_CalcConc PCB congeners 149 and 123; 2,2',3,4',5',6-Hexachlorobiphenyl and 2,3',4,4',5'-Pentachlorobiphenyl combined concentrations expressed in nanograms per liter. USGS Defined 0.000864 0.00889 Nanograms per liter PCB_118_CalcConc PCB congener 118; 2,3',4,4',5-Pentachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000898 0.015672 Nanograms per liter PCB_134_CalcConc PCB congener 134; 2,2',3,3',5,6-Hexachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000118 0.001562 Nanograms per liter PCB_114_131_CalcConc PCB congeners 114 and 131; 2,3,4,4',5-Pentachlorobiphenyl and 2,2',3,3',4,6-Hexachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.000222 0.003241 Nanograms per liter PCB_146_CalcConc PCB congener 146; 2,2',3,4',5,5'-Hexachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.00021 0.001989 Nanograms per liter PCB_153_CalcConc PCB congener 153; 2,2',4,4',5,5'-Hexachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000727 0.006022 Nanograms per liter PCB_132_CalcConc PCB congener 132; 2,2',3,3',4,6'-Hexachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000746 0.010235 Nanograms per liter PCB_105_CalcConc PCB congener 105; 2,3,3',4,4'-Pentachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 6.6e-05 0.001242 Nanograms per liter PCB_141_CalcConc PCB congener 141; 2,2',3,4,5,5'-Hexachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000453 0.004683 Nanograms per liter PCB_176_130_137_CalcConc PCB congeners 176,130 and 137; 2,2',3,3',4,6,6'-Heptachlorobiphenyl, 2,2',3,3',4,5'-Hexachlorobiphenyl and 2,2',3,4,4',5-Hexachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 8.2e-05 0.000814 Nanograms per liter PCB_163_138_CalcConc PCB congeners 163 and 138; 2,3,3',4',5,6-Hexachlorobiphenyl and 2,2',3,4,4',5'-Hexachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.001422 0.014602 Nanograms per liter PCB_158_CalcConc PCB congener 158; 2,3,3',4,4',6-Hexachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000161 0.001973 Nanograms per liter PCB_178_129_CalcConc PCB congeners 178 and 129; 2,2',3,3',5,5',6-Heptachlorobiphenyl and 2,2',3,3',4,5-Hexachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.00011 0.001083 Nanograms per liter PCB_175_CalcConc PCB congener 175; 2,2',3,3'4,5',6-Heptachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 1e-05 0.000152 Nanograms per liter PCB_187_182_CalcConc PCB congeners 187 and 182; 2,2',3,4',5,5',6-Heptachlorobiphenyl and 2,2',3,4,4',5,6'-Heptachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.00017 0.002751 Nanograms per liter PCB_183_CalcConc PCB congener 183; 2,2',3,4,4',5',6-Heptachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 7.6e-05 0.001216 Nanograms per liter PCB_128_CalcConc PCB congener 128; 2,2',3,3',4,4'-Hexachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000354 0.004348 Nanograms per liter PCB_185_CalcConc PCB congener 185; 2,2',3,4,5,5',6-Heptachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 2.5e-05 0.000409 Nanograms per liter PCB_174_CalcConc PCB congener 174; 2,2',3,3',4,5,6'-Heptachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000172 0.002788 Nanograms per liter PCB_177_CalcConc PCB congener 177; 2,2',3,3',4,5',6'-Heptachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000112 0.001581 Nanograms per liter PCB_202_171_156_CalcConc PCB congeners 202, 171 and 156; 2,2',3,3',5,5',6,6'-Octachlorobiphenyl, 2,2',3,3',4,4',6-Heptachlorobiphenyl and 2,3,3',4,4',5-Hexachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 3.4e-05 0.000557 Nanograms per liter PCB_157_200_CalcConc PCB congeners 157 and 200; 2,3,3',4,4',5'-Hexachlorobiphenyl and 2,2',3,3',4,5,6,6'-Octachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 3.6e-05 0.000583 Nanograms per liter PCB_172_197_CalcConc PCB congeners 172 and 197; 2,2',3,3',4,5,5'-Heptachlorobiphenyl and 2,2',3,3',4,4',6,6'-Octachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 3.9e-05 0.00089 Nanograms per liter PCB_180_CalcConc PCB congener 180; 2,2',3,4,4',5,5'-Heptachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 0.000228 0.003077 Nanograms per liter PCB_193_CalcConc PCB congener 193; 2,3,3',4',5,5',6-Heptachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 1.2e-05 0.000149 Nanograms per liter PCB_191_CalcConc PCB congener 191; 2,3,3',4,4',5',6-Heptachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 1.1e-05 7.601973 Nanograms per liter PCB_199_CalcConc PCB congener 199; 2,2',3,3',4,5,5',6'-Octachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 3e-06 4.4e-05 Nanograms per liter PCB_170_190_CalcConc PCB congeners 170 and 190; 2,2',3,3',4,4',5-Heptachlorobiphenyl and 2,3,3',4,4',5,6-Heptachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 0.000139 0.001104 Nanograms per liter PCB_198_CalcConc PCB congener 198; 2,2',3,3',4,5,5',6-Octachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 2e-06 3.4e-05 Nanograms per liter PCB_201_CalcConc PCB congener 201; 2,2',3,3',4,5',6,6'-Octachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 7.4e-05 0.001199 Nanograms per liter PCB_203_196_CalcConc PCB congeners 203 and 196; 2,2',3,4,4',5,5',6-Octachlorobiphenyl and 2,2',3,3',4,4',5,6'-Octachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 7.1e-05 0.00115 Nanograms per liter PCB_208_195_CalcConc PCB congeners 208 and 195; 2,2',3,3',4,5,5',6,6'-Nonachlorobiphenyl and 2,2',3,3',4,4',5,6-Octachlorobiphenyl combined concentration expressed in nanograms per liter. USGS Defined 2.2e-05 0.000187 Nanograms per liter PCB_207_CalcConc PCB congener 207;2,2',3,3',4,4',5,6,6'-Nonachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 2e-06 1.9e-05 Nanograms per liter PCB_194_CalcConc PCB congener 194; 2,2',3,3',4,4',5,5'-Octachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 2.1e-05 0.000346 Nanograms per liter PCB_205_CalcConc PCB congener 205; 2,3,3',4,4',5,5',6-Octachlorobipheny concentration expressed in nanograms per liter. USGS Defined 1e-06 1.3e-05 Nanograms per liter PCB_206_CalcConc PCB congener 206; 2,2',3,3',4,4',5,5',6-Nonachlorobiphenyl oncentration expressed in nanograms per liter. USGS Defined 1.1e-05 8.5e-05 Nanograms per liter PCB_209_CalcConc PCB congener 209; Decachlorobiphenyl concentration expressed in nanograms per liter. USGS Defined 8e-06 9.162791 Nanograms per liter GS ScienceBase U.S. Geological Survey mailing address

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