North Pole Refinery Documents

Updated: November 7, 2024

Fact Sheets

North Pole Refinery Contamination At a Glance November 2024 | (PDF version of this fact sheet): Alaska Department of Environmental Conservation.; This fact sheet is a summary published to update North Pole residents and others interested in the state’s response to groundwater contamination at and north of the former North Pole Refinery. Recent project milestones are discussed. (Updated from the May 2023 version); Posted 11/7/2024; North Pole Refinery Contamination At a Glance May 2023 | (PDF version of the 2023 fact sheet); Posted 5/8/2023
PFAS Present in Fish in Kimberly Lake September 2020: As part of the investigation summarized in the November 2019 fact sheet on DEC's PFAS investigation in the North Pole area, three fish from Kimberly Lake were sampled. Both PFOS and PFNA were measured at levels of concern in all three fish.; Posted July 18, 2019, updated September 29, 2020
How to Test Your Water for Sulfolane December 2019: Alaska Department of Environmental Conservation.; This fact sheet offers step-by-step advice for choosing a lab and testing your water. If you decide to proceed with sampling, follow the steps presented.; Posted 9/30/2020, contact information updated 5/8/2023
How to Test Your Water for PFAS March 2019 - Updated June 2023: Alaska Department of Environmental Conservation.; This fact sheet offers step-by-step advice for choosing a lab and testing your water. If you decide to proceed with sampling, follow the steps presented.; Posted 9/30/2020, updated 6/12/2023

November 2019 - PFAS Study in North Pole Area Water - Updated September 29, 2020: An update to the March 2019 and October 2018 fact sheets on DEC's PFAS investigation in the North Pole area, this provides results of the two phases of 2018 water testing and includes DEC's April 9, 2019, revised technical memorandum on action levels for PFAS that align the DEC action levels with EPA’s Lifetime Health Advisory levels.; Posted 9/2020

The National Toxicology Program's Research on Sulfolane (PDF) November 2019: Alaska Department of Environmental Conservation.; The NTP has embarked on toxicology studies for sulfolane that will address questions regarding long-term exposure to the solvent, as well as other research gaps.; Posted 9/30/2020, first version published 6/2015

Perfluoroalkyl Substances (PFAS) in Drinking Water (PDF), November 25, 2019. See the Alaska Department of Health's PFAS page.: Alaska Department of Health and Social Services; Posted: 8/2020

PFAS Study in North Pole Area Produce, July 2019 | (PDF version of this fact sheet): DEC recently evaluated the uptake of PFAS into garden produce irrigated with PFAS contaminated groundwater. Produce and soil samples were collected from a farm in North Pole to evaluate impacts from irrigation water containing PFAS. The results of this evaluation are summarized in this fact sheet.; Posted July 18, 2019

DEC's Contaminated Groundwater Advisory, North Pole Water Expansion Area, November 2018 (PDF version of this advisory): DEC issued a Contaminated Groundwater Advisory to all property owners within the North Pole piped water expansion area where many private water wells contain sulfolane, and/or per- and poly-fluoroalkyl substances (PFAS). The advisory is designed to assist residents in avoiding unintentional contact with, or spreading of, the chemicals.; Also see Groundwater Advisory FAQs; Posted 10/1/20

February 2018 Update on the North Pole Water System Expansion Project: This fact sheet gives an update on the progress toward expanding the City of North Pole public water system to provide sulfolane-free drinking water for residents affected by releases of sulfolane from the former Flint Hills North Pole Refinery. (Updated from a December 2017 version); Posted 3/5/18

December 2017 Update on the North Pole Water System Expansion Project (PDF): This fact sheet gives an update on the progress toward expanding the City of North Pole public water system to provide sulfolane-free drinking water for residents affected by releases of sulfolane from the former Flint Hills North Pole Refinery.; Posted 12/20/17

Summary of Settlement Agreement, Providing Public Water System Expansion, North Pole, Alaska, February 2017 (PDF): The State of Alaska and City of North Pole reached a settlement with Flint Hills Resources Alaska to secure sulfolane-free drinking water for residents affected by releases of sulfolane from the former Flint Hills North Pole Refinery. This Fact Sheet summarizes key provisions of the settlement.; Posted 2/24/17

Public Water vs. Private Well Water: a Comparison (PDF): This fact sheet discusses the differences and compares the cost of each system for a typical household in North Pole, Alaska.; Posted 2/24/17, updated 12/2017

The 2017 Revised Onsite Cleanup Plan & Offsite Potable Water Plan (PDF 2.6M): A component of the Settlement Agreement between Flint Hills Resources Alaska, the State of Alaska, and the City of North Pole.; Posted 2/24/17

Update on the Sulfolane Issue at the North Pole Refinery, April 2014: Posted 4/28/14

Health Recommendations and Next Steps (PDF) June 2013 (Contact information updated December 2014): Includes a map of the plume.; Posted 7/8/13

Developing a Groundwater Cleanup Level for Sulfolane (PDF)
Published February 2013: Posted 2/21/13

Final Results of the North Pole Garden Sampling Project (PDF): Published 1/18/2011, contact information updated 2/24/17

Results of the North Pole Garden Sampling Project: Testing of Early Harvest Plants for Sulfolane, August 2010: Posted 8/16/10

Community Health Concerns about Sulfolane, April 2010: Posted 4/22/10

Contaminated Sites Program Update on Sulfolane Cleanup, February 2010: Posted 2/3/10

Sulfolane Health Fact Sheet, January 2010: Posted 1/12/10

Sulfolane Material Safety Data Sheet by Chevron Phillips: Revision date 6/25/2009; Posted 2/2010

Understanding Contaminant Concentrations June 2009: Posted 2/2010

Introduction to Groundwater June 2009: Posted 2/2010

Newsletters

November 2018 - DEC Sulfolane Response Update | (PDF 1.4MB): Piped water service construction and sign-up; PFAS investigation into North Pole area groundwater; What are PFAS?; What are action levels?; From the Project Manager's desk; DEC's Contaminated Groundwater advisory; Posted: 11/28/2018
August 2015 - DEC Sulfolane Investigation Update (PDF 1.5M): NTP begins new studies on sulfolane; chart with Status of National Toxicology Program studies on sulfolane; Sulfolane cleanup level status; No cleanup level - What does it mean?; Cleanup proceeds at refinery, plume monitoring continues; Aerial map of sulfolane groundwater plume; A brief history; Posted: 8/10/2015
June 2014 - DEC Sulfolane Investigation Update (PDF): Effort to aid construction projects in plume; Health recommendations: a review and summary; Soil does not retain sulfolane; Posted: 6/6/2014
December 2013 - DEC Sulfolane Investigation Update (PDF): Additional sampling continues to provide more pieces of the puzzle; DEC cleanup process graphic; Cleanup timeline graphic; Report from Flint Hills; Gravel pits: sulfolane not detected; DEC hears from residents; Posted: 12/5/13
June 2013 - DEC Sulfolane Investigation Update (PDF): Frequently asked questions (updated); Posted: 6/17/13
February 2013 - DEC Sulfolane Investigation Update (PDF): DEC announces sulfolane cleanup level; EPA ponders future course of action at refinery; The investigation continues at the refinery; Pilot testing shows air sparging removes sulfolane; Posted: 2/13/13
September 2012 - DEC Sulfolane Investigation Update (PDF): Current work seeks better understanding of plume; FHR’s air sparging pilot test shows promise; UAF team studies biodegradation value in cleaning up sulfolane contamination; Posted: 9/13/12; Project timeline - Timeline Only in a larger format (PDF)
April 2012 - DEC Sulfolane Investigation Update (PDF): NTP accepts sulfolane, initiates toxicity studies; DHSS fact sheet offers garden watering guidance; FHR contributes to project’s progress; Source control key to preventing contamination; TPT subgroups status report; Posted: 4/27/12
January 2012 - DEC Sulfolane Investigation Update (PDF): Sulfolane nomination ‘strongly supported’ to the National Toxicology Program; UAF groundwater study; Schedule update; Update: Water alternatives and residential sampling; DHSS Health Consultation completed; Development of sulfolane toxicity values advanced; TPT subgroups’ status report; Sulfolane community survey results; Posted: 1/23/12
October 2011 - DEC Sulfolane Investigation Update (PDF): DEC established faster cleanup schedule; Federal assistance requested for new sulfolane study; FHR drinking water sampling and resampling efforts; TPT background; Spill drill tests FHR’s emergency capabilities; TPT subgroups’ update; Posted: 10/21/11
April 2011 - DEC North Pole Sulfolane Newsletter (PDF): Progress to date in the sulfolane investigation and cleanup: the TPT at work; Subgroup activities: Site Characterization and Remediation, Chemistry, Drinking Water, Toxicology, and Communications.; Next Steps; Timeline of response activities Oct. 2009 – March 2011; Glossary, TPT organization chart, plume map; Sulfolane research; Posted: 4/18/11

Frequently Asked Questions

Frequently Asked Questions | PDF version: Posted: 5/8/2023
Frequently Asked Questions - posted 9/30/20, replaced 5/8/23 PDF: Posted: 09/30/2020
City of North Pole's Water Service Connection FAQs - for Zones 1 and 2: Posted: 11/18
DEC's PFAS Action Levels FAQs - (PDF) (8/18): Posted: 11/18
Construction FAQs - for Zones 3 and 4, by Stantec, Inc. (PDF) (2/18): Posted: 2/18
Frequently Asked Questions - posted 3/21/18, replaced 9/30/20 (PDF): Posted: 3/21/18
Frequently Asked Questions Regarding Construction, City of North Pole Water Expansion, by Stantec, Inc. published January 2018.: Posted: 3/21/18
Frequently Asked Questions - posted 12/20/2017, replaced 3/21/18 (PDF): Posted: 12/20/17
Frequently Asked Questions - posted 10/24/2017, replaced 12/20/17 (PDF): Posted: 10/24/17
Frequently Asked Questions - posted 2/7/2017, replaced 10/24/2017 (PDF): Posted: 2/24/17
Frequently Asked Questions - posted 6/9/2015, replaced 2/7/2017 (PDF): Posted: 6/9/15
Frequently Asked Questions - posted 5/31/2013, replaced 6/9/2015 (PDF): Posted: 6/9/15
Frequently Asked Questions - various dates, replaced by updated FAQ web page 5/31/13 (PDF): Posted: 5/31/13
Frequently Asked Questions - June 2011 (PDF): Posted: 6/16/11

Press Releases

Fairbanks Superior Court Decision Finds Former Refinery Owner Must Pay Damages to State for Sulfolane Pollution in North Pole Drinking Water (PDF) Alaska Department of Law: The Superior Court in Fairbanks issues a decision holding Williams Alaska Petroleum, Inc. (Williams) liable for releasing large quantities of a refinery solvent known as sulfolane into the groundwater under the North Pole Refinery, polluting hundreds of residents’ drinking water wells.; January 3, 2020
Walker-Mallott Administration Takes Action to Provide Clean Drinking Water near Flint Hills (PDF): State Reaches Agreement with Flint Hills Resources Alaska on Public Water System Expansion; February 7, 2017
DEC Continues Protection of North Pole Drinking Water; Studies Are Initiated to Determine Effects of Long Term Exposure to Sulfolane (PDF): June 9, 2015
State Approves Cleanup Plan for North Pole Refinery (PDF): October 20, 2014
TERA to organize meeting in Fairbanks regarding the toxicity value for sulfolane (PDF): September 3, 2014
North Pole sulfolane health impact evaluation released (PDF): January 19, 2012
Test results released from sulfolane garden project: Press Release, January 18, 2011 (PDF); Fact Sheet, January 18, 2011 (PDF)
Sulfolane levels low or undetected in tested North Pole garden plants (PDF): August 16, 2010

Drinking Water: Project Specific Reports and Documents

Revised 2024 Alternative Water Supply Plan, Former North Pole Refinery, North Pole, Alaska (10M) June 12, 2024: Integral Consulting Inc., prepared for Williams Petroleum Alaska; Work plan to evaluate properties that are near the former refinery and are are not connected to municipal water for possible alternative water supplies; Posted 11/7/2024
Alternative Water Solutions Program 2016 Annual Report, North Pole, Alaska - February 2017 (PDF 9.6M) Published March 31, 2017: Arcadis U.S. Inc.; Maps of Alternative Water Solutions (PDF 2.3M); Posted 10/24/2017
Alternative Water Solutions Program 2015 Annual Report, North Pole, Alaska - February 2016 (PDF 4M), published February 26, 2016: Barr Engineering Co.; Posted 6/22/2016
Alternative Water Solutions Program 2014 Annual Report, North Pole, Alaska (PDF 4M) , published February 25, 2015: Barr Engineering Co.; Posted 6/22/2016
Alternative Water Solutions Program - Management Plan - published October 2014 (PDF 1.44): Barr Engineering Co.; (Large file size prevents us from posting Figures and/or Appendices; to see them, please contact DEC); Posted 10/20/2014
Water Quality Association certification for point-of-entry treatment systems (PDF), August 1, 2011, date of issue: Water Quality Association, International Headquarters & Laboratory, Lisle, IL.; Posted 6/26/2014
Laboratory Key Elements for Sulfolane Analysis in Water, Soil and Plants. (PDF), July 22, 2013, effective date: Posted 6/26/2014
Sulfolane Technical Assistance and Evaluation Report (PDF), published June 1, 2010: Prepared for the Alaska Department of Environmental Conservation by Oasis Environmental of Anchorage, Alaska.; Executive Summary on Sulfolane Research Report (PDF); Appendices A-E (PDF 3.7M); Appendix F (PDF 8M); Posted June 1, 2010
Water Quality Guidelines for Sulfolane (PDF), published October 2001: Prepared by: Komex International Ltd. of Calgary, Alberta for the British Columbia Ministry of Water, Land and Air Protection, Water Management Branch; Posted October 2010

Reference Materials

"Canadian Environmental Quality Guidelines for Sulfolane: Water and Soil / Scientific Supporting Document" (PDF), published 2006: Published by the Canadian Council of Ministers of the Environment
An investigation of maximum allowable concentration of sulfolane in surface water (PDF), published 1987: Zhu Zhenhua, et al, Department of Environmental Hygiene, West China University Medical school; Xiao Bangliang, et al, Research Unit of Toxicology; Dong Yunhua, et al, Department of Clinical Medical Laboratory.; Published in Journal of West China University Medical Society 18(4), 376-380. 1987
Gas chromatographic-mass spectrometric determination of sulfolane in wetland vegetation exposed to sour gas-contaminated groundwater (PDF), published in Journal of Chromatography A, 859 (1999) 69–75: by J.V. Headley, K.M. Peru, L.C. Dickson,

Site Characterization and Remediation: Project Documents and Reports

Offsite Plume

2022 Annual Monitoring and Five-Year (2017-2021) Offsite Sulfolane Plume Monitoring Report - Revision 1 (7M) January 2024: Integral Consulting, Inc., for Williams Alaska Petroleum, Inc.; This report documents both the 2022 annual monitoring of offsite sulfolane and evaluation of groundwater trends from 2017 through 2022.; Posted 11/7/2024

2021 Annual Offsite Sulfolane Plume Monitoring Report, City of North Pole and Surrounding Area - with Figures (2.3M), July 22, 2022: Integral Consulting, Inc., for Williams Alaska Petroleum, Inc.; This report was prepared to document the 2021 annual monitoring of sulfolane in groundwater located downgradient of the former refinery. The 2021 monitoring included the sampling of 47 monitoring wells and 16 private wells. While not all of the wells in the 2020 Plan were sampled due to logistical challenges, an evaluation of 2021 sample results has shown that overall, the observed 2021 concentrations are consistent with previous groundwater maps and show a generally stable plume footprint.

For copies of Tables or Appendix items or other help with this report, please contact DEC.

Posted 5/8/2023

2020 Annual Offsite Sulfolane Plume Monitoring Report, City of North Pole and Surrounding Areas - with Figures (1.8M), March 30, 2022: Integral Consulting, Inc., for Williams Alaska Petroleum, Inc.; This report was prepared to document the 2020 annual monitoring of sulfolane in groundwater located downgradient of the former refinery, which was conducted generally as described in the scope of work approved by the ADEC. The 2020 monitoring included the sampling of 48 monitoring wells and 85 private wells identified in the 2020 Work Plan. This report also documents the final monitoring of 42 private wells fitted with point of entry (POE) systems for sulfolane removal. While not all of the wells in the 2020 Plan were sampled due to access constraints and other logistical challenges, an evaluation of available data has shown that overall, the observed 2020 concentrations of sulfolane are consistent with previous groundwater maps and show a stable plume footprint.

For copies of Appendix items or other help with this report, please contact DEC.

Posted 5/8/2023

2020 Annual Offsite Sulfolane Plume Monitoring Plan, City of North Pole and Surrounding Areas (2M), August 19, 2020: Integral Consulting, Inc., for Williams Alaska Petroleum, Inc.; This monitoring plan outlines the 2020 annual monitoring of sulfolane in groundwater located downgradient of the former refinery. This 2020 Plan is a revision to FHRA’s previously prepared 2017 Long-Term Monitoring Plan and includes the sampling of 178 existing monitoring wells and private wells and reporting of results.

Posted 5/8/2023

2019 Offsite Plume Monitoring Report, with Tables, Figures and Appendix A (6.8M), January 8, 2020: Arcadis; This document describes long-term monitoring of the sulfolane plume beyond the former refinery property (i.e., offsite) to meet the annual reporting requirements of the "Offsite Sulfolane Potable Water Plan" (a plan for extending the City of North Pole’s piped water system to areas affected by sulfolane groundwater contamination). Annual reporting for the Alternative Water Solutions Program is also included in this report. Sampling of POE systems that remain in operation will conclude by the end of 2020 now that construction the City’s expanded public water system is completed, after which the alternative water supply systems will be phased out.

For copies of Appendix items or other help with this report, please contact DEC.

Posted: 9/29/2020

2018 North Pole Per- and Polyfluoroalkyl Substances Water Sampling Report, PFAS (4.8M), December 2019: Ahtna Engineering Services, Inc.; In summer and fall 2018, samples were collected from water supply wells, monitoring wells and surface water in North Pole, Alaska, and analyzed for per- and polyfluoroalkyl substances (PFAS). The water sampling was initiated after PFAS were detected at concentrations approximately equal to the United States Environmental Protection Agency’s (EPA’s) lifetime health advisory level in samples from monitoring wells at the former North Pole Refinery property boundary. The overall objectives of this sampling project included identification and preliminary delineation of the PFAS plume migrating off the former refinery property and evaluating whether the public is protected from exposure to PFAS in drinking water.

Posted: 9/29/2020

2018 Offsite Groundwater Sulfolane Plume Monitoring Report, December 20, 2018

Arcadis

This document describes long-term monitoring of the sulfolane plume beyond the former refinery property (i.e., offsite) to meet the requirements of the "Offsite Sulfolane Potable Water Plan" (a plan for extending the City of North Pole’s piped water system to areas affected by sulfolane groundwater contamination).

Posted 3/13/19

2017 Offsite Groundwater Sulfolane Plume Monitoring Plan, City of North Pole and Fairbanks Borough (PDF 1.7M), June 2017: Arcadis; This document describes long-term monitoring of the sulfolane plume beyond the former refinery property (i.e., offsite) that is planned to meet the requirements of the "Offsite Sulfolane Potable Water Plan" (a plan for extending the City of North Pole’s piped water system to areas affected by sulfolane groundwater contamination).; Posted 6/21/18

2017 Final Interim Management Plan for Excavation Dewatering (Revised), North Pole Sulfolane Plume, October 2017 (PDF 5M): Ahtna Engineering Services, Inc.; Provides guidance for managing excavation water generated during construction dewatering activities in the vicinity of the North Pole sulfolane groundwater plume.; Posted 10/24/17
2017: Annual 2017 Offsite Plume Monitoring Report, North Pole Terminal, February 9, 2018 (PDF 5.6M): Submitted to DEC by Flint Hills Resources Alaska, LLC, Arcadis; Offsite monitoring (of plume beyond the refinery). This report represents a transition from semiannual to annual reporting. In addition, annual reporting for the Alternative Water Solutions Program is now included in this comprehensive report. Sampling of POE systems will continue until construction the City of North Pole’s expanded public water system (PWS) is completed, after which the alternative water supply systems will be phased out:; For copies of Appendix items or other help with this report, please contact DEC.; Posted: 3/20/18

2016 Offsite Groundwater Monitoring Report

Submitted to DEC by Flint Hills Resources Alaska, LLC, Arcadis

Offsite monitoring (of plume beyond the refinery)

For copies of Appendix items or other help with this report, please contact DEC.

Posted: 3/22/17

2015 Offsite Groundwater Monitoring Reports

Arcadis, submitted to DEC by Flint Hills Resources Alaska, LLC, January 2014

Offsite monitoring (of plume beyond the refinery):

For copies of Appendix items or other help with this report, please contact DEC.

Posted: 6/22/16

Report: Garden Soil Sampling, March 2014

ERM

Results of soil samples from lawns and flower gardens in the North Pole area watered with sulfolane-laden water. No sulfolane was detected, indicating that the use of sulfolane-contaminated water at these locations did not leave residual sulfolane in the soil.

Posted: 6/5/14

Report: North Pole Gravel Pond and Slough Sampling, November 2013

ERM

Results of sulfolane in surface water and sediment from several water bodies located within the sulfolane-affected area in North Pole. No sulfolane was detected above the reporting limit in gravel or surface water.

Posted: 6/6/14
Third-party review of lab analysis of North Pole city water: "Assessment of Sulfolane Split-Sample Data Associated with the Flint Hills Resources Fuel Refinery in Fairbanks, Alaska,"(PDF), published December 9, 2009: Environmental Standards Inc.; Posted: 12/9/09

Onsite Plume

2023 Annual Onsite Groundwater Monitoring Report, (2M) January 16, 2024: Arcadis U.S., Inc., prepared for Flint Hills Resources Alaska, LLC; Groundwater monitoring on the former refinery through 2023 has shown no indications of contamination migrating off the former refinery property above allowable limits. In samples from wells near the property boundary, petroleum (benzene, diesel-range organics, and gasoline-range organics) concentrations are below Alaska cleanup levels, and sulfolane concentrations are below the allowable limit.; Posted 11/7/2024

2022 Annual Onsite Groundwater Monitoring and Five-Year Periodic Review, North Pole Terminal (7.4M), January 24, 2023, with Tables and selected Figures: Submitted to DEC by Flint Hills Resources Alaska, LLC, Arcadis; Onsite (on refinery property) monitoring, summarizing onsite field activities completed during the first and third quarters of 2022.

For copies of the complete set of Figures or other help with this report, please contact DEC.

Posted 11/7/2024

2021 Annual Onsite Groundwater Monitoring Report, North Pole Terminal, December 13, 2021 (7.4M), December 13, 2021, with Figures: Submitted to DEC by Flint Hills Resources Alaska, LLC, Arcadis; Onsite (on refinery property) monitoring, summarizing onsite field activities completed during the first and third quarters of 2021.

For copies of other Appendix items or other help with this report, please contact DEC.

Posted 5/8/2023

2020 Annual Onsite Groundwater Monitoring Report, North Pole Terminal, December 21, 2021 (6.7M), December 21, 2021, with Figures: Submitted to DEC by Flint Hills Resources Alaska, LLC, Arcadis; Onsite (on refinery property) monitoring, summarizing onsite field activities completed during the first and third quarters of 2020.

For copies of other Appendix items or other help with this report, please contact DEC.

Posted 5/8/2023

2019 Annual Onsite Groundwater Monitoring Report, North Pole Terminal (7.9M), December 2, 2019, with Tables and Figures: Submitted to DEC by Flint Hills Resources Alaska, LLC, Arcadis; Onsite (on refinery property) monitoring), summarizing onsite field activities completed during the first and third quarters of 2019.; For copies of other Appendix items or other help with this report, please contact DEC.; Posted: 9/29/2020

2017 Onsite Groundwater Monitoring Reports

Submitted to DEC by Flint Hills Resources Alaska, LLC, Arcadis

Onsite (on refinery property) monitoring:

For copies of other Appendix items or other help with this report, please

2016 Onsite Groundwater Monitoring Reports

Submitted to DEC by Flint Hills Resources Alaska, LLC, ArcadisOnsite (on refinery property) monitoring:

For copies of Appendix items or other help with this report, please contact DEC.Posted: 3/22/17

2015 Onsite Groundwater Monitoring Reports

Submitted to DEC by Flint Hills Resources Alaska, LLC, Arcadis

Onsite (on refinery property) monitoring:

For copies of Appendix items or other help with this report, please contact DEC.Posted: 6/22/16

Onsite Cleanup Plan Documents, 2014 and later

2017 Revised Onsite Cleanup Plan, North Pole Terminal, North Pole, Alaska, (PDF 2.1M), published February 2, 2017

Arcadis

This document updates the remedy described in the 2014 Onsite Cleanup Plan for the former refinery property. The remedy was modified as part of the February 2017 agreement to extend the City of North Pole’s piped water system to areas impacted by the sulfolane plume. The 2017 ROCP includes an updated onsite long-term monitoring plan.

Posted: 6/21/18

2015 Operation, Monitoring, and Maintenance (OMM) Plan, 2015 Update, Groundwater Remediation System (PDF 3.4M), published December 2015

Barr Engineering

2015 Long-Term Groundwater Monitoring Plan, 2015 Update, December 14, 2015, Arcadis (PDF 6.9M)

Posted: 6/22/16

2015 Onsite Excavation Report, North Pole Terminal, North Pole, Alaska, November 30. 2015 (PDF 11.5M)

Arcadis

This report summarizes excavation activities completed during 2015 within Lagoon B, the Southwest Former Wash Area, and the Fire Training Area. The scope of the soil excavation work is defined in Section 5.3 of the Final Onsite Cleanup Plan (Arcadis 2014).

Posted: 6/22/16

Final Onsite Cleanup Plan, North Pole Refinery, October 2014, (PDF)

Arcadis

Large file size prevents us from posting Figures and/or Appendices; to see them, please contact DEC

Posted: 10/20/14

Site Characterization Documents

2024 Soil Characterization Work Plan Technical Memorandum, for PFAS on the former refinery property (2.2M) July 1, 2024

Integral Consulting Inc., prepared for Williams Petroleum Alaska

In summer 2024, Williams submitted work plans for long-term PFAS groundwater monitoring, additional soil and groundwater characterization, and fish sampling on the former refinery.

2024 Onsite Soil and Groundwater Characterization Work Plan, Integral (1.3M)
2024 Fish Tissue Sampling and Analysis for PFAS Work Plan - Onsite Integral (1M)

Posted 11/7/2024

2023 Updated Site Characterization Report for PFAS Onsite PFAS report, former North Pole Refinery, North Pole, Alaska (7M) January 2024: Integral Consulting Inc., prepared for Williams Petroleum Alaska; Sampling performed in 2022 showed PFAS above DEC’s soil cleanup level on the refinery and PFAS in groundwater above DEC’s action level migrating off the former refinery.; Posted 11/7/2024

Offsite Plume Technical Memorandum Addendum, Rev. 1. – Groundwater; Williams Alaska Petroleum, Inc.; Former North Pole Refinery; North Pole, AK (3.2M), published July 28, 2022: Integral, submitted to DEC by Williams Alaska Petroleum, Inc.; This memorandum documents the plan for the next phase of PFAS characterization activities on the former refinery. The plan includes soil, groundwater, and surface water sampling as followup activities to the 2020 characterization activities.; Posted 5/8/2023

2021 Site Characterization Report – Groundwater; Williams Alaska Petroleum, Inc.; Former North Pole Refinery; North Pole, AK (3.4M), published August 25, 2021: Integral, submitted to DEC by Williams Alaska Petroleum, Inc.; This document presents the results of focused characterization activities on the former refinery property to assess the horizontal and vertical extent of per-and polyfluoroalkyl substances (PFAS) in groundwater and surface water and to identify potential areas for future evaluation.

For copies of laboratory data or other help with this report, please contact DEC.

Posted 5/8/2023

Work Plan Technical Memorandum, Rev. 1. Onsite Groundwater and Surface Water PFAS Characterization Workplan; Williams Alaska Petroleum, Inc.; Former North Pole Refinery; North Pole, AK (1.4M), published September 24, 2020: Integral, submitted to DEC by Williams Alaska Petroleum, Inc.; This memorandum documents onsite groundwater and surface water PFAS (per- and polyfluoroalkyl substances) characterization activities on the former refinery.; Posted 5/8/2023

2013 DRAFT Onsite Site Characterization Addendum Report (PDF 1M), published December 20, 2013

Arcadis, submitted to DEC by Flint Hills Resources Alaska, LLC.

This document presents site characterization data collected in 2013 and the results of technical analyses based on these data. The technical analyses and discussions in this Onsite Addendum are informed by the full data set collected over the total site history and by historical findings.

For copies of Figures and Tables or other help with this report, please contact DEC.

Posted: 6/22/16

2013 DRAFT Offsite Site Characterization Addendum Report (PDF 15M), published December 20, 2013

Arcadis, submitted to DEC by Flint Hills Resources Alaska, LLC.

This Offsite Addendum outlines results from field activities conducted in 2013. It also presents additional interpretations and conclusions based on ongoing private and monitoring well sampling and a review of the full data set for the site.

For copies of Figures and Tables or other help with this report, please contact DEC.

Posted: 6/22/16

2013 Onsite Site Characterization Work Plan (PDF 5.1M) submitted to DEC by Flint Hills Resources Alaska, LLC, published February 2013

Arcadis

Appendix (PDF 7.7M)

This work plan addresses recommendations presented in previous Site Characterization Reports and DEC's requests for additional site assessment on the refinery property.

Posted: 5/10/13

2013 Offsite Site Characterization Work Plan (PDF), published March 2013

Arcadis, submitted to DEC by Flint Hills Resources Alaska, LLC.

This work plan addresses recommendations presented in previous Site Characterization Reports and DEC's requests for additional site assessment. "Offsite" is the area located outside the refinery's property boundary in the downgradient north-northwest direction, based on the approximate extent of the dissolved phase sulfolane plume.

For copies of Appendix items or other help with this report, please contact DEC.

Posted: 5/10/13

Site Characterization Report - 2012 Addendum, submitted to DEC by Flint Hills Resources Alaska, LLC, published January 25, 2013

Arcadis

Describes additional site characterization activities that ARCADIS and Shannon and Wilson, Inc. conducted during the second and third quarters of 2012. This is an addendum to the "Revised Site Characterization Report, March 2012, Barr Engineering" found below.

For copies of Appendix items or other help with this report, please contact DEC.

Posted: 5/10/13

Site Characterization Report, through 2011 - FINAL (PDF 1.9M), published December 2012

Barr Engineering for Flint Hills Resources Alaska, LLC, submitted to DEC

Description of site characterization work completed through 2011 by Flint Hills Resources Alaska, LLC.

Posted: 8/11/14

December 2009 Monthly Groundwater Remediation Status Report, published 1987-2006

from Flint Hills Resources to DEC.

Includes historical benzene sampling from 1987 and sulfolane concentrations from 2006. References two maps of the current groundwater concentrations from shallow (water-table) monitoring wells.

1987-2006

Contaminant Characterization Study, for Williams Alaska Petroleum, Inc. (PDF 2M), published 2001.

Shannon and Wilson

Identified sulfolane as a contaminant; has monitoring results.

Posted: 2001

Interim Cleanup Documents

2024 October - Interim Removal Action Work Plan Technical Memorandum - On-Refinery PFAS(7.5M) October 3, 2024

Integral Consulting Inc., prepared for Williams Petroleum Alaska

In early October 2024, DEC approved this interim remedy work plan work to be initiated in October 2024 on the former refinery property. Sampling performed in 2022 showed PFAS above DEC’s soil cleanup level on the refinery and PFAS in groundwater above DEC’s action level migrating off the former refinery property.

Posted: 11/7/2024

2024 Onsite PFAS Remedial Alternatives Analysis Matrix, former North Pole Refinery (2.4M) May 31, 2024

Integral Consulting Inc., prepared for Williams Petroleum Alaska

In July 2024, DEC approved Williams' evaluation of potential remedies to address PFAS remaining in soil and groundwater on the former refinery property.

Posted: 11/7/2024

Interim Remedial Action Plan Addendum (PDF) July 31, 2013

Arcadis, submitted to DEC by Flint Hills Resources Alaska, LLC

This plan Addendum proposes additional interim remedial actions to address light nonaqueous phase liquid (LNAPL) and groundwater impacts at the North Pole Refinery. This Addendum focuses on constituents of concern identified in the 2012 Revised Draft Final Human Health Risk Assessment and data collected during site characterization activities.

Posted: 6/22/16

DEC's approval letter of 2002 Corrective Action Plan, January 24, 2006, setting sulfolane cleanup level (PDF)

Posted: 1/24/06

June 2002 Site Characterization and Corrective Action Plan (PDF 3.3M)

submitted to DEC for Williams Alaska Petroleum, Inc. (formerly MAPCO Alaska Petroleum, Inc.). and approved by DEC in January 2006 after Flint Hills Resources Alaska, LLC. acquired the refinery.

Posted: June 2002

Reference Materials

Report on groundwater flow in the Fort Wainwright area: "Estimate of Aquifer Properties by Numerically Simulating Ground-Water/Surface-Water interactions, Fort Wainwright, Alaska," (PDF 5.3M) 1998: by Allan S. Nakanishi and Michael R. Lilly for the U.S. Geological Survey; This study used a model to mimic the flow of water between the aquifer and the Chena River at Fort Wainwright. The USGS collects groundwater and surface-water data to understand the movement of water through the ground in the area. Data was collected monthly and sometimes more frequently to document short-term changes in groundwater caused by rapid changes in the Chena and Tanana Rivers. This document is in part used to guide DEC's conclusions about how groundwater moves in the area of North Pole.; Published: 1998
Groundwater levels in an Alluvial Plain Between the Tanana and Chena Rivers (PDF 4M) 1996: Latest USGS report describing the regional groundwater flow in the Fairbanks North Star Borough.; Published: 1996

Human Health and Toxicology: Project Documents and Reports

Fact Sheet on Perfluoroalkyl Substances (PFAS) in Drinking Water (PDF), November 25, 2019

Alaska Department of Health and Social Services

Posted: 8/2020

DEC's Contaminated Groundwater Advisory, North Pole Water Expansion Area, November 2018 (PDF version of this advisory)

DEC issued a Contaminated Groundwater Advisory to all property owners within the North Pole piped water expansion area where many private water wells contain sulfolane, and/or per- and poly-fluoroalkyl substances (PFAS). The advisory is designed to assist residents in avoiding unintentional contact with, or spreading of, the chemicals.

Also see Groundwater Advisory FAQs

Posted 10/1/20

Report of the Expert Peer Review of Sulfolane Reference Doses for the Alaska Department of Environmental Conservation, published December 2014

TERA (Toxicology Excellence for Risk Assessment)

Report on an independent, expert peer review of the available reference doses (RfDs) for sulfolane. The peer review meeting was held September 16-17, 2014 in Fairbanks, Alaska.

See TERA's website on the Independent Expert Peer Review of Sulfolane Reference Doses for ADEC.

Posted: 12/22/14

Garden Soil Sampling Report, Tables only (PDF 378K), March 2014

ERM

Report with all Attachments (PDF 4M)

Posted: 6/5/14

Fact Sheet: Sulfolane Groundwater Contamination in North Pole: Health Recommendations and Next Steps (PDF) June 2013 (Contact info updated December 2014)

Alaska Department of Health and Social Services, Division of Public Health, Section of Epidemiology, Environmental Public Health Program.

Posted: 7/8/13

EPA Provisional Peer-Reviewed Toxicity Values for Sulfolane (CASRN 126-33-0) (PDF), January 30, 2012

U.S. Environmental Protection Agency, Office of Research and Development, National Center for Environmental Assessment, Superfund Health Risk Technical Support Center.

Posted: 11/27/12

DHSS Health Consultation - Sulfolane Plume in Groundwater: Evaluation of Community Concerns about Sulfolane in Private Water Wells, January 19, 2012 (PDF)

Alaska Department of Health and Social Services, Division of Public Health, Section of Epidemiology, Environmental Public Health Program.

Posted: 1/19/12

National Toxicology Program Board of Scientific Counselors, Summary Minutes, December 15, 2011, National Institute of Environmental Health Sciences, Research Triangle Park, NC (PDF)

Minutes from the review of the concept, at the meeting of the NTP's Board of Scientific Counselors - see page 8.

Posted: 6/22/16

Presentation on sulfolane at the NTP Board of Scientific Counselors Meeting, December 15, 2011, by Chad Blystone, Ph.D., D.A.B.T. National Institute of Environmental Health Sciences (PDF)

Posted: 6/22/16

ATSDR Health Consultation on Sulfolane, May 2, 2011 (PDF)

Agency for Toxic Substances and Disease Registry, Emergency Response Team.

Posted: 5/2/11

DHSS Press release "Tests results released from sulfolane garden project," January 18, 2011 (PDF)

Alaska Department of Health and Social Services, Division of Public Health, Section of Epidemiology.

Posted: 7/24/14

Final Results of the North Pole Garden Sampling Project, January 18, 2011 (contact info updated 1/8/2014) (PDF)

Alaska Department of Health and Social Services, Division of Public Health, Section of Epidemiology.

Posted: 1/18/11

DHSS Press Release on the North Pole Garden Sampling Project: "Sulfolane levels low or undetected in tested North Pole garden plants." August 16, 2010 (PDF)

Alaska Department of Health and Social Services

Posted: 7/24/14

Results of the North Pole Garden Sampling Project: Testing of Early Harvest Plants for Sulfolane, August 16, 2010 (PDF)

Alaska Department of Health and Social Services, Division of Public Health, Section of

Posted: 8/16/10

Community Health Concerns about Sulfolane, April 22, 2010 (PDF)

Alaska Department of Health and Social Services, Division of Public Health, Section of Epidemiology.

Posted: 4/22/10

ATSDR Health Consultation on Sulfolane, February 3, 2010 (PDF)

Agency for Toxic Substances and Disease Registry, Emergency Response Team.

Companion Guide to ATSDR's Health Consultation on Sulfolane, February 9, 2010 (PDF)

Alaska Department of Health and Social Services, Division of Public Health, Section of Epidemiology.

Posted: 2/9/10

Sulfolane Health Fact Sheet, January 12, 2010 (PDF)

Alaska Department of Health and Social Services, Division of Public Health, Section of Epidemiology.

Posted: 1/12/10

Reference Materials

Particle Size Distribution and Inhalation Dose of Shower Water Under Selected Operating Conditions, April 2007 (PDF 1.4M): Inhalation Toxicology, April 2007, volume 19(4), pages 333-342. Yue Zhou, Janet M. Benson, Clinton Irvin, Hammad Irshad and Yung-Sung Cheng, Lovelace Respiratory Research Institute, Albuquerque, New Mexico. (The author manuscript is through the National Institutes of Health Public Access system. The NIH is part of the U.S. Department of Health and Human Services.); Posted: 4/13/12
Acute Toxicity and Skin Irritant Properties of Sulfolane, 1966 British Journal of Industrial Medicine, 1966, volume 23, pages 302-304 (PDF): (The British Journal of Industrial Medicine is now published as Occupational & Environmental Medicine.) V.K.H. Brown, L.W. Ferrigan and D.E. Stevenson, from Shell Research Ltd., Tunstall Laboratory, Sittingbourne, Kent, England; received for publication on April 13, 1966.; Posted: 4/10/12
Studies on Toxicokinetics of 3H-Sulfolane in Rat after Oral Administration, 1988 (PDF): Journal of West China University Medical Society, 1988, volume 19, pages 61-64. Zhu Zhenhua, Gao Ning, Guo Jitong, Sun Mianling, Wu Desheng and Yang Zaichang, of the Department of Environmental Hygiene, West China University Medical school. Also, Li Zhimin and Lei Youdao of the Laboratory of Isotopes, Institute of Atomic Energy, Chinese Academy of Sciences.; Posted: 2010

Analytical Method

Laboratory Key Elements for Sulfolane Analysis in Water, Soil and Plants. Effective July 22, 2013 (PDF): Posted: 12/11/13

Technical Project Team Documents

In March of 2010, DEC's Contaminated Sites Program created a Technical Project Team (TPT) to provide comprehensive and coordinated oversight for the sulfolane release investigation at the North Pole Refinery. The team consisted of technical representatives from DEC, the Alaska Dept. of Health and Social Services, the U.S. Environmental Protection Agency, Flint Hills, and Williams Tesoro. Each contributed experts in toxicology, engineering, hydrology, environmental chemistry and other relevant fields, and the team was coordinated by a professional facilitator. The team's last meeting was October 23, 2013.

Division of Spill Prevention and Response Contaminated Sites