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NPDES General Permit for Small Suction Dredge Placer Miners in Idaho

Transfer of permitting authority to Idaho: As of July 1, 2020, EPA has transferred authority to administer and enforce this permit to the Idaho Department of Environmental Quality. For more information, visit Idaho Pollutant Discharge Elimination System (IPDES) Program.Exit

NOIs and annual reports: Please send Notices of Intent (NOIs) to Annual reports should be submitted via Idaho's IPDES E-Permitting System.

The EPA has reissued its National Pollutant Discharge Elimination System (NPDES) general permit for small suction dredge miners in Idaho, effective June 1, 2018. Refer to the permit documents below for changes from the previous permit.


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About this Permit

Permit number: IDG370000
Effective date: June 1, 2018

Expiraton date: May 31, 2023

Operators of small suction dredges in Idaho must obtain NPDES permit coverage. The permit places conditions on the discharge of rock and sand from each mining operation to protect water quality and aquatic resources. These conditions include best management practices and prohibited areas.

EPA's general permit covers small suction dredges with:

  1. An intake nozzle size of five inches in diameter or less.
  2. Equipment rated at 15 horsepower or less.

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How to Apply for Coverage

  1. Read the permit (see "Documents" below).
  2. Confirm that the waterbody you wish to work in is eligible for a permit from the Idaho Department of Water Resources (IDWR) Stream Channel Protection Program Exitand the EPA (see Table 1 of the general permit). You will need permits from both agencies to dredge in Idaho.
  3. Fill out and submit a Notice of Intent (NOI) Information Sheet (see "Documents" below).
  4. Wait for written authorization from the EPA before operating.
  5. Remember to submit an Annual Report Information Sheet (see "Documents" below).

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Open and Closed Waters in Idaho

Open Waters

Mores Creek, Grimes Creek, Elk Creek, and their tributaries are permitted annually (see permit parts I.G.1.a and II.B.2), with an application deadline of April 1 each year.

Fifteen (15) dredges can be permitted annually on the South Fork Clearwater River (SFCR). See permit parts I.G.1.b and II.B.3, and IDWR’s South Fork Clearwater River Special SupplementExit (see Recreational Mining Permit Forms) published annually for further information.

Elsewhere in Idaho, open waters are eligible for coverage until the permit's expiration date. Applications are welcome year-round. See Table 1 of the general permit to confirm which areas are open.

Closed Waters

Permit part I.D lists categories of waters that are closed to dredging, including:

  1. Nationally Protected Areas.
  2. Tribal Reservations.
  3. National Wild and Scenic Rivers.
  4. Endangered Species Habitat Areas.
  5. Withdrawn Rivers.
  6. State Protected Rivers.
  7. Impaired Streams.

For more information about closed waters and any exceptions that may exist, refer to the general permit.

Critical Habitat Areas

Many popular areas (e.g., Middle Fork Boise River, South Fork Payette, Salmon River, Clearwater River) have been designated as critical habitat for threatened or endangered species protected under the Endangered Species Act (ESA), and are not open to dredging at this time. A process known as ESA consultation must be completed before the EPA can authorize suction dredging in critical habitat areas, or where threatened and/or endangered species are present (see permit part I.D.4).

See Endangered Species Critical Habitat Areas in Idaho and Map of Chinook Salmon Evolutionarily Significant Units (ESU) in Idaho under "Documents" below.

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Forms and Permit Documents

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.