Michigan Dept. of Environment, Great Lakes, and EnergyDrilling Unit: A regulated maximum area, built from the governmentally surveyed quarter, quarter sections of land. It is the area which may be efficiently and economically drained by a well or wells. Uniform Spacing Plans (USP): An area of land subject to S.O. 14-9-94, pooled in multiples of governmentally surveyed quarter, quarter sections, and controlled by one operator for the purpose of locating Antrim wells to minimize surface waste. Visit this page for additional information on spacing orders . Data is updated on a regular basis as new permits are issued. For more information, visit Michigan.gov/EGLE/Maps-Data/GeoWebFace or contact EGLE-GeoWebFace@michigan.gov . Field Name Field Descriptions FID ESRI ID Shape Shape (polygon for everything) PermitNumber GRMD Assigned Permit Number. Assigned a '0' for USPs since there are multiple permits in each unit. SpacingCode Spacing Code Assigned (see table below) Comment Populated with pertinent information about the permit or unit and the USP name for USPs FormationName Formation name TownshipRange Township Range location SPACING CODES (SpacingCode Field) EXPLANATION CODE DESCRIPTION 1 FIELD SPACING 2 GENERAL RULE, 40 ACRES 3 S.O. 1-73, 80 ACRES 4 S.O. 12-6-75, 80 ACRES 5 S.O. 2-81, 40 ACRES 6 S.O. 9-7-84, 20 ACRES 7 S.O. 1-86, 640 ACRES 8 S.O. 10-12-87, 40 ACRES 9 S.O. 14-9-94, 80 ACRES 10 S.O. 3-3-95, 40 ACRES 11 S.O. 24-8-05, 80 ACRES 12 RULE 303 (2) EXCEPTION 13 VOLUNTARY POOLED PRE-303 14 ACT 9 (GAS ACT), 160 ACRES 15 GENERAL RULE, 10 ACRES 16 PRIVATE CLAIMS AREA 17 S.O. 18-2007 18 UNIFORM SPACING PLANArcGIS FeatureLayerhttps://hub.arcgis.com/datasets/fea03434794144ddb5b00d1863db368c_1engState of Michigan Open Data PortalPublicMichigan Drilling Units and Uniform Spacing Plans for Permitted Oil and Gas Wells [Michigan]Web servicesMichiganLast Modified: 2026-01-06