Brooke A. Kline Andrew J. Sekellick Emily H. Majcher 20251209 tabular digital data Reston, VA U.S.Geological Survey https://doi.org/10.5066/P13IVMXG This metadata record contains two tables with reported and calculated amounts of biosolids applied to agricultural land within Virginia in 2024 at different scales. Included in the dataset are (1) mass of land-applied biosolids calculated for NHDPlus Version 2.1 (NHDPlusV2) reach catchments in 2024 as a CSV and (2) reported amount of biosolids applied to land by county in 2024 as a CSV, reported by Virginia Department of Environmental Quality. Reported amounts of field applied biosolids were downscaled to assess the mass of land-applied biosolids within the Chesapeake Bay watershed at the NHDPlusV2 catchment and county scales Appropriate use of the data includes statistical analysis, model parameterization, and map creation or display. 2024 observed Complete None planned Virginia -83.6700 -75.2400 39.4500 36.5400 ISO 19115 Topic Category environment None Biosolids Chesapeake Bay National Hydrography Dataset (NHD) USGS Thesaurus Hydrology USGS Metadata Identifier USGS:686ec84ad4be020e5c0a6bcf Common geographic areas Virginia None Chesapeake Bay No access constraints. Please see 'Distribution Information' for details. These data are marked with a Creative Common CC0 1.0 Universal License. These data are in the public domain and do not have any use constraints. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations. USGS - Northeast Region Emily H Majcher Hydrologist mailing and physical

MD/DE/DC WSC UMBC Campus, UMBC Research Park

Catonsville MD 21228 443-498-5520 emajcher@usgs.gov Data provided by Virginia Department of Environmental Quality. Data aggregation work was funded by the United States Geological Survey Ecosystems Mission Area, Chesapeake Bay Studies and performed by USGS. Environment as of Metadata Creation: Microsoft Windows 11 Enterprise, Version 23H2, build 22631.5335; Esri ArcGIS Pro 3.4.3; RStudio version 2025.05.0 (Build 467); R version 4.5.0 (2025-05-22). Virginia Department of Environmental Quality 20250206 spreadsheet Richmond, VA Virginia Department of Environmental Quality Biosolid land application permitted sites are available here (https://apps.deq.virginia.gov/EDM/). Field application of biosolids applied in 2024 was provided through written communication (Bryan Cauthorn, 02/06/2025). Calculated NHDPlus catchment level data were assessed for obvious errors and compared to county-level data as provided. All attributes were checked for outliers and whether the data were within the feasible range for the data represented. Data set is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details. No formal positional accuracy tests were conducted. No formal positional accuracy tests were conducted. R Core Team 20241031 publication Vienna, Austria R Foundation for statistical computing https://www.R-project.org/ Digital and/or Hardcopy 2024 version 4.4.2 release date R Software Documentation for R software Virginia Department of Environmental Quality 20250206 spreadsheet Richmond, VA Virginia Department of Environmental Quality Biosolid land application permitted sites are available here (https://apps.deq.virginia.gov/EDM/). Field application of biosolids applied in 2024 was provided through written communication (Bryan Cauthorn, 02/06/2025). Digital and/or Hardcopy 2024 observed VA DEQ Dry Tons Applied column used in the Daily Field Activity tab of spreadsheet VA DEQ - Office of Land Application 20201112 tabular digital data https://apps.deq.virginia.gov/arcgis/rest/services/public/EDMA/MapServer/207 Digital and/or Hardcopy 2020 publication date Biosolid Areas Boundary of permitted sites that includes one or more land application fields. Lucinda McKay Timothy Bondelid Thomas G. Dewald 2012 publication Washington D.C. Office of Water, United States Environmental Protection Agency (EPA) https://www.epa.gov/system/files/documents/2023-04/NHDPlusV2_User_Guide.pdf Digital and/or Hardcopy 2012 publication date NHDPlusV2 NHD Plus Catchments Kyle Walker 2025 R Package https://CRAN.R-project.org/package=tigris Digital and/or Hardcopy 2025 R package version 2.2.1 tigris County FIPS Daniel Baston 2023 R Package https://CRAN.R-project.org/package=exactextractr Digital and/or Hardcopy 2023 R package version 0.10.0 exactextractr Extraction of values from biosolid application raster. Robert J. Hijmans 2025 R Package https://CRAN.R-project.org/package=terra Digital and/or Hardcopy 2025 R package version 1.8-50 terra Creation of raster from a shape file. Daily Field Activity biosolids data with DEQ Control IDs were provided by the Virginia Department of Environmental Quality (VA DEQ) Biosolids Program. The Daily Field Activity biosolids table included the amount of biosolids applied daily in dry tons with corresponding DEQ Control IDs. Daily amounts of biosolids at each application field were summed for the entire year of 2024. A Biosolid Areas polygon geographic layer with DEQ Control IDs was downloaded from Virginia Department of Environmental Quality. VA DEQ Biosolid Areas 20250210 Daily Field Activity was summed by counties. Federal Information Processing Series (FIPS) codes and sum of biosolids were exported as a CSV (“BS_mass_VA_county_2024.csv”). County data were downloaded from the U.S. Census Bureau using the “list_counties” command with the “tigris” package in RStudio. VA DEQ tigris 20250211 Applied biosolids amounts were joined to the Biosolid Areas polygons layer by matching DEQ Control IDs in ArcGIS Pro. VA DEQ Biosolid Areas 20250612 The Biosolid Areas polygon geographic layer was imported into RStudio. Dry tons were converted to kilograms and acres were converted to square meters. A rate or density of biosolids application was calculated as a kilogram per square meter for each biosolid area. The polygon layer was converted into a 30-meter square resolution raster using this density value and the “terra ” package. The density was then multiplied by 900. R Software terra 20250612 Using “exactextractr” package, the “exact_extract” function was used to summarize values from the raster created in the previous step in a table containing the sum of added biosolids within National Hydrography Dataset version 2 (NHDv2) catchments. The sum of biosolids was then converted from kilograms to pounds. The table, now containing Federal Information Processing Series (FIPS) codes and the sum of biosolids in pounds, was exported as a CSV (“BS_mass_VA_nhdv2_2024.csv”). Only catchments with an applied biosolid mass greater than zero are included in the table. R Software exactextractr NHDPlusV2 20250612 BS_mass_VA_nhdv2_2024.csv Comma Separated Value (CSV) file containing the summed amount of biosolids applied to land in Virginia by NHDPlus catchment in 2024. Producer Defined FEATUREID Catchment Identifier from NHDPlus Version 2. Producer Defined 1088429 22539732 Biosolid_lbs Summed amount of biosolids applied to agricultural land in pounds (lbs). Producer Defined 940 3645200 Pounds BS_mass_VA_county_2024.csv Comma Separated Value (CSV) file containing the summed amount of biosolids applied to land in Virginia by county in 2024. Producer Defined County County names Producer Defined Virginia county names County_Applied_FIPS The Federal Information Processing Series (FIPS) code for where the biosolids were applied. The first two digits of the 5-digit code represent the state code, while the last three digits represent the county code. U.S. Geological Survey 51001 51840 Biosolid_Tons Total reported amount of biosolids applied to the land in tons. Producer Defined 0.0 11502.78123 Tons U.S. Geological Survey - ScienceBase mailing address

Denver Federal Center

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Denver CO 80225 1-888-275-8747 sciencebase@usgs.gov Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. Digital Data https://doi.org/10.5066/P13IVMXG None 20251209 USGS - Northeast Region Emily H Majcher Hydrologist mailing and physical

MD/DE/DC WSC UMBC Campus, UMBC Research Park

Catonsville MD 21228 443-498-5520 emajcher@usgs.gov FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata FGDC-STD-001.1-1999