Total Radon-222 Activity in Submarine Groundwater Collected Along the West Florida Shelf and Offshore Nature Coast, Indian Rocks Beach, and Venice Headland, Florida, USA, Between November 2022 and March 2024

Scientists from the U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center (SPCMSC) led six sampling events between November 2022 and March 2024 in support of a collaborative research project investigating coastal boundary fluxes of dissolved analyte loads to the West Florida Shelf (National Science Foundation Grant Award OCE-2148989, Project 880516). During each trip, scientists sampled marine groundwater wells at three coastal transects (named for nearby geography: Nature Coast (NC) near Hudson, Florida (FL); Indian Rocks Beach (IRB) near Indian Rocks Beach, FL; and Venice Headland (VH) near Venice, FL). This data release provides total radon-222 activity in water for small volume groundwater samples collected from marine wells during six sampling events. These data were assigned a USGS Field Activity Number (FAN) for the entire study period (2022-340-FA), and alternate FANs for the individual sampling trips (22WFS05, 23WFS01, 23WFS02, 23WFS03, 23WFS04, and 24WFS01). Samples were collected and analyzed by liquid scintillation counting (LSC) using methods from Prichard and Gesell (1977). Total radon-222 activity dissolved in groundwater are reported in units of disintegrations per minute per liter of water (dpm/L). Additional analyses are published from this study, including short-lived radium-isotopes (Chestang and others, 2025) and water column radon-222 (Smullen and others, 2026).

Chestang, E.S., Ellis, A.M., Smith, C.G., Knapp, A., Tamborski, J.J., and Lindgren, A., 2025, Short-lived radium-isotope (Radium-223 and -224) specific activity for samples collected between November 2022 and March 2024 along the West Florida Shelf (Indian Rocks Beach, Nature Coast, and Venice Headland) (ver. 2.0, August 2025): U.S. Geological Survey data release, https://doi.org/10.5066/P1ZIOFSX.

Smullen, B.F., Ellis, A.M., Smith, C.G., Knapp, A., Tamborski, J.J., Lindgren, A., Boiteau, R., Buck, K., Caprara, S., Chappell, D., Conway, T., Hunt, H., and Alorda-Kleinglass, A., 2026, Total radon-222 activity measured in water column samples collected from coastal waters of the West Florida Shelf and offshore Nature Coast, Indian Rocks Beach, and Venice Headland, Florida, USA, between November 2022 and March 2024: U.S. Geological Survey data release, https://doi.org/10.5066/P14SUDX3.

Prichard, H.W. and Gesell, T.F., 1977, Rapid measurements of 222Rn concentrations in water with a commercial liquid scintillation counter: Health Physics, vol. 33 no. 6, p. 577-581, https://doi.org/10.1097/00004032-197712000-00008.