This rulemaking was initiated to update Idaho’s human health criteria for arsenic. Negotiated under Docket No. 58-0102-1801 and adopted under Docket No. 58-0102-2201.
Rule package submitted to EPA for approval on July 6, 2023.
EPA Action Letter and Technical Support Document received on September 29, 2023.
For more information, go to EPA Actions on Proposed Standards.
- EPA Action Letter and Technical Support Document
EPA approved Docket No. 58-0102-2201 with exception of disapproving the provision, in IDAPA 58.01.02.210.03.e.v.(4), to calculate bioaccumulation factors using “… other scientifically defensible method for deriving protective BAF.”
- DEQ Submittal Letter to EPA
- Technical Justification – Idaho Human Health Criteria for Arsenic
- Attorney General Certification of Revised Water Quality Standards, Docket No. 58-0102-2201
This submittal also includes documents that exist as part of the rulemaking record and posted below.
DEQ held meetings for the development of guidance for updates to Idaho’s human health criteria for arsenic.
The updates to Idaho’s human health criteria for arsenic were negotiated under Docket No. 58-0102-1801 and published as a proposed rule under Docket No. 58-0102-2201. The pending rule was adopted by the Idaho Board of Environmental Quality on May 26, 2022, and will be submitted to the Idaho Legislature for review during the 2023 legislative session. The pending rule includes the rule as initially proposed along with revisions in Subsections 210.01.b., Footnote k, and 210.03.e. and is available here. Once the pending rule is approved by the Idaho Legislature, DEQ will submit the rule to EPA for review.
In May 2016, EPA entered into a Consent Decree with Northwest Environmental Advocates to reconsider EPA’s 2010 approval of Idaho’s human health criteria for arsenic. In September 2016, EPA disapproved Idaho’s human health criteria of 10 µg/L arsenic for both consumption of fish only and consumption of fish & water. The Consent Decree requires that EPA propose new human health criteria for arsenic by November 15, 2018, and that EPA either approve Idaho’s submittal of revised human health criteria for arsenic or promulgate federal criteria by July 15, 2019.
In June 2018, the Court granted the Unopposed Motion to Modify Consent Decree, extending the Consent Decree Paragraph 5 deadlines to November 15, 2022, and the Paragraph 6 deadlines to November 15, 2023.
In June 2022, the Court granted the Unopposed Second Motion to Modify Consent Decree, extending the Consent Decree Paragraph 5 deadlines to November 15, 2023, and the Paragraph 6 deadlines to November 15, 2024.
The Consent Decree and modifications are posted as Additional Information on negotiated rulemaking web page Docket No. 58-0102-1801.
This rulemaking will enable Idaho to adopt human health criteria for arsenic under state rulemaking and may prevent federal promulgation of criteria for Idaho by EPA.
Guidance Development Meeting Details
No meeting scheduled.
Method for Participating and Submitting Comments
Those interested in participating in the guidance development process are encouraged to attend the scheduled meetings.
Submit all written comments and direct questions to:
Idaho Department of Environmental Quality
1410 N. Hilton, Boise, ID 83706
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|Guidance Documents and Meeting Presentations||Date Posted||Date of Meeting||Written Comment Deadline|
|Arsenic Guidance Document Development – DEQ PowerPoint Presentation November 15, 2022|
(Includes Proposed Outline for Guidance Development)
|Comment||Submitted by||Date Received|
|Comment on June 2023 Draft Implementation Guidance||U.S. EPA Region 10||07/25/23|
|Comment on June 2023 Draft Implementation Guidance||J.R. Simplot Company||07/24/23|
|Comment on Implementation Guidance Draft No. 1||U.S. EPA Region 10||02/28/23|
|Comment on Implementation Guidance Draft No. 1||Idaho Association of Commerce & Industry (IACI)||02/28/23|
|Comment on Implementation Guidance Draft No. 1||Association of Idaho Cities (AIC)||02/28/23|
|Comment on Proposed Outline for Guidance Development||U.S. EPA Region 10||11/30/22|
|Comment on Final Proposal|
(Submitted During May 26, 2022 Board Meeting)
|Association of Idaho Cities (AIC)||05/26/22|
|Comment on Proposed Rule||Association of Idaho Cities (AIC)||04/01/22|
|Comment on Proposed Rule||Idaho Association of Commerce & Industry (IACI)||04/01/22|
|Comment on Proposed Rule||U.S. EPA Region 10||04/01/22|
Pending rules submitted to the 2023 Idaho Legislature for review
2023 Legislative Rules Review Books
- House Environment, Energy & Technology Committee
- Senate Resources & Environment Committee
Board of Environmental Quality
May 25 – Board tour of Bunker Hill Mine area
May 26 – Business meeting
9 a.m. PDT
Panhandle Health District
35 Wildcat Way, Kellogg, ID
This meeting is in person or via zoom. Attendance details are in the Meeting Notice and Agenda.
Notice of Rulemaking – Adoption of Pending Rule
(Only those subsections that have changed from the original proposed rule text are included in this publication. The changes are in Subsection 210.01.b., Footnote k, and Subsection 210.03.e.)
April 6, 2023
No information is available at this time.
No information is available at this time.