Skip to main content

Silver Bow Creek/Butte Area Superfund Site

Submissions from 2026 2026

Draft Final 2023 Unreclaimed Sites Sampling: UR-42 Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Draft Final 2023 Unreclaimed Sites Sampling: UR-43 Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Draft Final 2024 Reclamation Improvement Sampling: BRES No. 78 – Original Mine Yard Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Draft Final 2024 Unreclaimed Sites Sampling: UR-21 Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Draft Final 2024 Unreclaimed Sites Sampling: UR-46 Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Draft Final 2025 BPSOU Subdrain Data Summary Report (DSR), Pioneer Technical Services, Inc.

Draft Final Annual Operations and Maintenance (O&M) Report: Butte Treatment Lagoon (BTL) System – 2025, Pioneer Technical Services, Inc.

Draft Final Annual Operations and Maintenance (O&M) Report: Butte Treatment Lagoon (BTL) System – 2025, Pioneer Technical Services, Inc.

Draft Final BPSOU Unreclaimed Sites: UR-46 Remedial Action Work Plan (RAWP), Pioneer Technical Services, Inc.

Draft Final Butte Mine Waste Repository Operation and Maintenance (O&M) Plan, Pioneer Technical Services, Inc.

Draft Final Butte Priority Soils Operable Unit (BPSOU) Insufficiently Reclaimed Sites BRES No. 30 – Atlantic 1 Remedial Action Work Plan (RAWP), Pioneer Technical Services, Inc.

Draft Final Butte Priority Soils Operable Unit (BPSOU) Insufficiently Reclaimed Sites Sister Dump (BRES No. 38) Remedial Action Work Plan (RAWP), Pioneer Technical Services, Inc.

Draft Final Butte Priority Soils Operable Unit Insufficiently Reclaimed Sites Temporary Best Management Practices Work Plan: BRES No. 16 – Curry and BRES No. 50 – Zelia, Pioneer Technical Services, Inc.

Draft Final Butte Priority Soils Operable Unit Unreclaimed Sites: UR-03 Construction Completion Report, Pioneer Technical Services, Inc.

Draft Final Butte Priority Soils Operable Unit Unreclaimed Sites: UR-03 Construction Completion Report, Pioneer Technical Services, Inc.

Draft Final Butte Priority Soils Operable Unit Unreclaimed Sites: UR-35 Construction Completion Report (CCR), Pioneer Technical Services, Inc.

Draft Final Quarterly Operations and Maintenance Report: Butte Treatment Lagoon System – First Quarter 2026, Pioneer Technical Services, Inc.

Draft Final Quarterly Operations and Maintenance Report: Butte Treatment Lagoon System – Fourth Quarter 2025, Pioneer Technical Services, Inc.

Draft Final Silver Bow Creek Conservation Area Materials Management Plan Revision 1, Pioneer Technical Services, Inc.

Draft Final Silver Bow Creek Conservation Area (SBCCA) Butte Reduction Works (BRW) Air Monitoring for Interim Demolition Activities – Phase II Data Summary Report (DSR), Pioneer Technical Services, Inc.

Final 2022 Insufficiently Reclaimed Sites Sampling: BRES No. 16 Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Final 2022 Insufficiently Reclaimed Sites Sampling: BRES No. 30 – Atlantic-1 Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Final 2022 Insufficiently Reclaimed Sites Sampling: BRES No. 32 – Corra 2 Dump Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Final 2022 Insufficiently Reclaimed Sites Sampling: BRES No. 37 – Josephine Shaft Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Final 2022 Insufficiently Reclaimed Sites Sampling: BRES No. 38 – Sister Dump Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Final 2022 Insufficiently Reclaimed Sites Sampling: BRES No. 96 – Washoe Dump Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Final 2022 Unreclaimed Sites Sampling: UR-06 Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Final 2022 Unreclaimed Sites Sampling: UR-07 Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Final 2022 Unreclaimed Sites Sampling: UR-12 Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Final 2022 Unreclaimed Sites Sampling: UR-13 Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Final 2022 Unreclaimed Sites Sampling: UR-20 Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Final 2022 Unreclaimed Sites Sampling: UR-22 Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Final 2022 Unreclaimed Sites Sampling: UR-28 Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Final 2022 Unreclaimed Sites Sampling: UR-28 Site Evaluation Summary ReportFinal 2022 Unreclaimed Sites Sampling: UR-28 Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Final 2023 Unreclaimed Sites Sampling: UR-42 Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Final Annual Operations and Maintenance (O&M) Report: Butte Treatment Lagoon (BTL) System – 2023, Pioneer Technical Services, Inc.

Final Basinwide Quality Management Plan (QMP) – 2026-2030, Revision 0, Pioneer Technical Services, Inc.

Final BPSOU Unreclaimed Sites: UR-46 Remedial Action Work Plan (RAWP), Pioneer Technical Services, Inc.

Final Butte Priority Soils Operable Unit (BPSOU) Unreclaimed Sites: UR-08 (Anderson Shaft) Remedial Action Work Plan (RAWP), Pioneer Technical Services, Inc.

Final Butte Priority Soils Operable Unit (BPSOU) Unreclaimed (UR) Sites New and Mahoney (UR-23) Construction Completion Report (CCR), Pioneer Technical Services, Inc.

Final Insufficiently Reclaimed Sites Quality Assurance Project Plan (QAPP), Pioneer Technical Services, Inc.

Final Insufficiently Reclaimed Sites Quality Assurance Project Plan (QAPP), Pioneer Technical Services, Inc.

Final Quarterly Operations and Maintenance Report Butte Treatment Lagoon System – First Quarter 2025, Pioneer Technical Services, Inc.

Final Quarterly Operations and Maintenance Report: Butte Treatment Lagoon System – Fourth Quarter 2025, Pioneer Technical Services, Inc.

Final Quarterly Operations and Maintenance Report: Butte Treatment Lagoon System – Third Quarter 2025, Pioneer Technical Services, Inc.

Final Revised Silver Bow Creek Conservation Area (SBCCA) Construction Quality Assurance Plan (CQAP), Pioneer Technical Services, Inc.

Final Silver Bow Creek Conservation Area Materials Management Plan, Pioneer Technical Services, Inc.

Final Silver Bow Creek Conservation Area (SBCCA) Construction Quality Assurance Plan (CQAP), Pioneer Technical Services, Inc.

Final Unreclaimed Sites Quality Assurance Project Plan (QAPP), Pioneer Technical Services, Inc.

Final Unreclaimed Sites Quality Assurance Project Plan (QAPP), Pioneer Technical Services, Inc.

Revised Draft Final Annual Operations and Maintenance (O&M) Report: Butte Treatment Lagoon (BTL) System – 2025, Pioneer Technical Services, Inc.

Revised Draft Final Butte Mine Waste Repository Operation and Maintenance (O&M) Plan, Pioneer Technical Services, Inc.

Revised Draft Final Butte Priority Soils Operable Unit (BPSOU) Insufficiently Reclaimed Sites Josephine Shaft (BRES No. 37) Remedial Action Work Plan (RAWP), Pioneer Technical Services, Inc.

Revised Draft Final Butte Priority Soils Operable Unit (BPSOU) Unreclaimed (UR) Sites New and Mahoney (UR-23) Construction Completion Report (CCR), Pioneer Technical Services, Inc.

Revised Draft Final Butte Priority Soils Operable Unit (BPSOU) Unreclaimed (UR) Sites New and Mahoney (UR-23) Construction Completion Report (CCR), Pioneer Technical Services, Inc.

Revised Draft Final Quarterly Operations and Maintenance Report: Butte Treatment Lagoon System – First Quarter 2026, Pioneer Technical Services, Inc.

Revised Draft Final Quarterly Operations and Maintenance Report: Butte Treatment Lagoon System – Second Quarter 2025, Pioneer Technical Services, Inc.

Butte Priority Soils Operable Unit Butte Reduction Works Smelter Area Intermediate 60% Remedial Design Submittal, Pioneer Technical Services, Inc. and Atlantic Richfield Company

Third Butte RMAP Biomonitoring (Phase 3) Report, Ramboll and Atlantic Richfield Company

Approval letter for the Butte Priority Soils Operable Unit (BPSOU) 2025 Butte Reclamation Evaluation System (BRES) Site Specific Corrective Action Plans for Quadrant 2 (dated July 22, 2026), Molly Roby

Approval letter for the Butte Priority Soils Operable Unit (BPSOU) 2026 Final Backfill and Cover Soil Quality Assurance Project Plan (QAPP) dated August 26, 2026, Molly Roby

Approval letter for the Butte Priority Soils Operable Unit Field Sampling Plan and Investigation Plan: UR-41 - Montana Street and Interstate-90, Molly Roby

Approval letter for the Draft Final Butte Priority Soils Operable Unit (BPSOU) Unreclaimed Sites Field Sampling and Investigation Plan – UR-52 Area West of BRES No. 133 – Dexter Mill, Molly Roby

Approval letter for the Draft Final Butte Priority Soils Operable Unit Unreclaimed Sites Field Sampling and Investigation Plan: UR-53 – South of Surprise Dump, Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) 2022 Draft Final Insufficiently Reclaimed Sites Sampling: BRES No. 16 Site Evaluation Summary Report, Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Draft Final 2024 Reclamation Improvement Sampling: BRES No. 78 – Original Mine Yard Site Evaluation Summary Report, Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Draft Final Reclamation Improvement Field Sampling and Investigation Plan: BRES No. 160S – Syndicate Pit Dumps, Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Draft Final Reclamation Improvement Field Sampling and Investigation Plan: BRES No. 171 – Blaine Center, Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Draft Final Reclamation Improvement Field Sampling and Investigation Plan: BRES No. 180 – Tullamore Dump, Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Draft Final Reclamation Improvement Field Sampling and Investigation Plan: BRES No. 57 – Little Mina-1, Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Draft Final Reclamation Improvement Field Sampling and Investigation Plan: BRES No. 68 – Little Mina-2, Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Draft Final Reclamation Improvement Field Sampling and Investigation Plan: BRES No. 9 – Clark Street Dump, Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Draft Final Rock Creek Cattle Company Borrow Submittal #2 (dated February 4, 2026), Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Draft Final Unreclaimed Sites: UR-27 Site Evaluation Summary Report (SESR), Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Draft Final Unreclaimed Sites: UR-42 Site Evaluation Summary Report (SESR) (dated July 22, 2026), Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Draft Final Whitehall Borrow Submittal #3 (dated March 27, 2026), Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Final Unreclaimed Sites Field Sampling Plan (FSP) Package #7: UR-01, UR-12, UR-03, UR-04, UR-15, and UR-17 Amendment (dated April 28, 2026), Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Revised Draft Final 2022 Unreclaimed Sites Sampling: UR-06 Site Evaluation Summary Report (dated December 10, 2025), Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Revised Draft Final 2022 Unreclaimed Sites Sampling: UR-12 Site Evaluation Summary Report (dated December 9, 2025), Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Revised Draft Final 2022 Unreclaimed Sites Sampling: UR-22 Site Evaluation Summary Report (dated December 10, 2025), Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Revised Draft Final Insufficiently Reclaimed Sites Joesphine Shaft (BRES No. 37) – Remedial Action Work Plan (RAWP) (dated March 24, 2026), Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Revised Draft Final Unreclaimed Sites: New and Mahoney (UR-23) Construction Completion Report (CCR), Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Revised Draft Final Unreclaimed Sites: UR-07 Site Evaluation Summary Report (SESR), Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Unreclaimed Sites: UR-03 Construction Completion Report (CCR), Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit - Draft Final 2022 Insufficiently Reclaimed Sites Sampling: BRES No. 96 – Washoe Dump Site Evaluation Summary Report, Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit Draft Final 2023 Insufficiently Reclaimed Sites Sampling: BRES No. 93 – Soudan Dump Site Evaluation Summary Report, Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit Draft Final Reclamation Improvement Field Sampling and Investigation Plan: BRES No. 75 – National Dump, Molly Roby

Re: Approval letter for the Butte Priority Soils Operable Unit, Draft Final Unreclaimed Sites: UR-31 Site Evaluation Summary Report, Molly Roby

Re: Approval letter for the Draft Final 2026 Butte Priority Soils Operable Unit (BPSOU) McDermott Basin Creek Water Treatment Plant Subsurface Fill Borrow Submittal #1, Molly Roby

Re: Approval letter for the Draft Final 2026 Butte Priority Soils Operable Unit (BPSOU) Type B Borrow Material Submittal #3 (dated May 6, 2026), Molly Roby

Re: Approval letter for the Draft Final Butte Priority Soils Operable Unit Insufficiently Reclaimed Sites Temporary Best Management Practices Work Plan: BRES No. 16 – Curry and BRES No. 50 – Zelia, Molly Roby

Re: Approval letter for the Draft Final Butte Priority Soils Operable Unit Unreclaimed Sites Field Sampling and Investigation Plan: UR 51 – Area near BRES No.50 –Zelia and Mountain Con Mine, Molly Roby

Re: Approval Letter for the Uncontrolled Surface Flow Areas Drainage C 95% Design Remedial Action Work Plan, Molly Roby

Re: Comment letter for the Butte Priority Soils Operable Unit (BPSOU) 2025 Butte Reclamation Evaluation System (BRES) Field Evaluation Summary Report and Technical Recommendations Proposal, Molly Roby

Re: Comment letter for the Butte Priority Soils Operable Unit (BPSOU) 2025 Butte Reclamation Evaluation System (BRES) Site Specific Corrective Action Plans for Quadrant 2, Molly Roby

Re: Comment letter for the Butte Priority Soils Operable Unit (BPSOU) 2026 Revised Draft Final Backfill and Cover Soil Quality Assurance Project Plan (QAPP) (dated January 5, 2026), Molly Roby

Re: Comment letter for the Draft Final Butte Priority Soils Operable Unit (BPSOU) Insufficiently Reclaimed Sites BRES No. 30 – Atlantic 1 Remedial Action Work Plan (RAWP) (dated March 24, 2026), Molly Roby

Re: Conditional approval letter for the Butte Priority Soils Operable Unit (BPSOU) 2026 Revised Draft Final Backfill and Cover Soil Quality Assurance Project Plan (QAPP) (dated May 13, 2026), Molly Roby

Re: Conditional Approval letter for the Butte Priority Soils Operable Unit (BPSOU) Draft Final Potential Logan, Montana, Borrow Source Site Environmental Assessment Checklist, Molly Roby

Re: Conditional approval letter for the Butte Priority Soils Operable Unit (BPSOU) Draft Final Unreclaimed Sites: UR-46 Remedial Action Work Plan (RAWP), Molly Roby