About

NEPA at U.S. Geological Survey

USGS actions are reviewed under the National Environmental Policy Act (NEPA) to evaluate potential environmental effects and to inform decision making. The process that determines the level of NEPA review depends on the nature and potential impacts of the proposed action. Described below are the three levels of review with CX's or CE's being the most widely used type of NEPA review used by USGS.

Categorical Exclusions (CXs, or CEs): Categorical exclusions "means a category of actions that a Federal agency has determined normally does not significantly affect the quality of the human environment." -516 DM1 - DOI Handbook of NEPA Implementing Procedures.

At USGS these include the following:

A. Topographic, land use and land cover, geological, mineralogic, resources evaluation, and hydrologic mapping activities, including aerial topographic surveying, photography, and geophysical surveying

B. Collection of data and samples…, and resource evaluation, including contracts therefor.

C. Acquisition of geological, hydrological or geophysical data from private exploration ventures.

D. Well logging, aquifer response testing, digital modeling, inventory of existing wells and water supplies, water-sample collection.

E. Operation, construction, installation, and removal—including restoration of sites to the pre-structure condition or equivalent of the surrounding environment—of hydrologic and water-quality monitoring structures and equipment including but not limited to weirs, cableways, streamgaging stations, groundwater wells, and meteorologic structures.

F. Routine exploratory or observation groundwater well drilling operations which do not require a special access road, and which use portable tanks to recycle and remove drilling mud, and create no significant surface disturbance.

G. Test or exploration drilling and downhole testing, including contracts thereof.

H. Establishment of survey marks, placement and operation of field instruments, and installation of any research/monitoring devices.

I. Digging and subsequent site restoration of exploratory trenches not to exceed one acre of surface disturbance.

J. Establishment of seasonal and temporary field camps.

K. Off-road travel to drilling, data collection or observation sites which does not impact ecologically sensitive areas such as wilderness areas, wetlands, or areas of critical habitat for listed endangered or threatened species.

L. Hydraulic fracturing of rock formations for the singular purpose of in situ stress measurements.

M. Reports to Surface Management Agencies, or any State, Territorial, Commonwealth or Federal Agencies concerning mineral and water resources appraisals.

N. Other actions where USGS has concurrence or coapproval with another Department of the Interior bureau and the action is a categorical exclusion for that bureau.

O. Minor, routine, or preventive maintenance activities at USGS facilities and lands, and geological, hydrological, or geophysical data collection stations.

P. Minor activities required to gain or prepare access to sites selected for completion of exploration drilling operations or construction of stations for hydrologic, geologic, or geophysical data collection.
Q. Restoration of noncontroversial native species into suitable habitats within their historic range and elimination of exotic species (as per Sec 109 of NEPA, Adopted NPS CE located at 516 DM 12.5, Sec. E. Federal Reg. Vol 89, No. 240 (Fri., Dec. 13, 2024)

Environmental Assessments (EAs): An EA is a document that identifies environmental effects of a proposed action and determines their significance. If it seems unlikely that a proposed action will have a significant effect on the environment, the USGS will prepare an EA. An EA describes the purpose and need for a proposed action, describes the affected environment, discusses alternatives to a proposed action, and analyzes environmental impacts and ways to mitigate them. If the EA shows that the proposed action does not have a significant effect on the environment, it will issue a Finding of No Significant Impact (FONSI). In some cases, if the analysis completed during an EA shows that the proposed action will have a significant effect on the environment, the USGS will complete a full EIS.

Finding of No Significant Impact (FONSI): If, after completing an EA, the USGS determines that an action will not have a significant effect on the environment, a Finding of No Significant Impact (FONSI) is prepared. This determination confirms that an environmental impact statement is not required. The USGS documents its FONSI in a Decision Record.

Environmental Impact Statements (EISs): An EIS is a comprehensive document that analyzes the impacts of a federal action that will have a significant effect on the human environment. An EIS describes the purpose and need for a proposed action, describes the affected environment, discusses alternatives to a proposed action, and analyzes environmental impacts and ways to mitigate them. An EIS is typically more comprehensive and detailed than an EA, and it offers more opportunities for public comment or involvement than an EA. An EIS has more procedural requirements, and therefore takes more time to prepare on average than an EA. Each EIS is completed with a Record of Decision, which documents The USGS decision as to how it will or will not move forward with a proposed action.