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Indiana Department of Environmental Management

Indiana Department of Environmental Management


Table of Contents: Water Quality

Storm Water Run-off - Industrial Sites

A revised version of the Rule 6 National Pollutant Discharge Elimination System (NPDES) general permit for Storm Water Runoff Associated with Industrial Activity became effective November 26, 2003. The revised Rule 6 (327 IAC 15-6) is consistent with Phase II federal Storm Water requirements. The IDEM Office of Water Quality provides a comprehensive online guidance on obtaining a Rule 6 permit.

Under the revised rule, most industrial facilities in Indiana are subject to the Rule 6 permitting requirements if: 1) run-off from a precipitation event or from ice or snow melt waters are exposed to (come into contact with) the facility's manufacturing processing activities, raw materials storage areas, or intermediate products storage areas; and, 2) that run-off then leaves the facility from one, or several, point source(s) that discharge into a Municipal Separate Storm Sewer System (MS4), or directly into the waters of the state.

It is always the facility operator, rather than the property owner, that is responsible for compliance with Rule 6, and/or other Storm Water discharge limitations and requirements.

Thirty-two (32) specific categories of industrial activities are often included within these parameters, as well as the following facilities:

  1. hazardous waste treatment, storage, or disposal facilities;
  2. landfills, land application sites, open dumps, and transfer stations;
  3. steam electric power generating facilities;
  4. wastewater treatment plants with a design flow of 1,000,000 gallons per day or more; and,
  5. agricultural chemical fertilizer and pesticide distribution facilities.

Who Does Not Need a Rule 6 Permit?

There are three (3) groups of facilities that may not be subject to Rule 6 requirements:

  1. Facilities for which an individual NPDES Storm Water permit (using application form 2F [PDF]) may be required, including those with subcategories and the associated effluent limitations listed in 40 Code of Federal Regulations (CFR), Parts 411 through 443), such as:
    1. Cement manufacturing;
    2. Feedlots;
    3. Fertilizer manufacturing;
    4. Petroleum refining;
    5. Phosphate manufacturing;
    6. Steam electric power generation;
    7. Coal mining (can also operate under a Rule 7 Permit);
    8. Mineral mining and processing;
    9. Ore mining and dressing; and,
    10. Asphalt manufacturing.
  2. Facilities that can successfully demonstrate eligibility for a conditional no exposure exclusion [PDF] (which must be granted by IDEM).
  3. Facilities for which IDEM determines that the general Rule 6 permit requirements would not be sufficient to protect water quality of the receiving stream, or because those facilities have other factors that may require more specific Storm Water control requirements. If an Individual Storm Water permit is required, IDEM will notify representatives at those facilities, who will have 30 days to submit an application for an individual NPDES discharge permit.

To obtain a conditional no exposure exclusion, a facility must certify on a conditional no exposure certification form [PDF] submitted to IDEM, and demonstrate during a subsequent IDEM inspection, that there are no industrial activities or materials exposed to storm water. Industrial materials and activities include, but are not limited to, material handling equipment or activities; industrial machinery; raw materials, intermediate products, by-products, and final products; or waste products. Material handling activities include storage, loading and unloading transportation or conveyance, of any raw material, intermediate product, by-product, final product or waste product.

Some of the Things a Facility Must Do To Comply With Rule 6 Include:

Facilities wishing to operate under a Rule 6 permit first must submit a Notice of Intent (NOI) to the IDEM Office of Water Quality (form available on the IDEM Forms page):

IDEM-Office of Water Quality
Rule 6 Storm Water Specialist
100 North Senate Avenue, MC 65-42
Indianapolis, IN 46204-2251

  1. The NOI letter must be submitted at least 90 days before beginning industrial operations at a new facility. Similarly, facilities that received notification from IDEM that they need to renew an existing Rule 6 permit, also have 90 days to submit a renewal NOI letter.
  2. The NOI letter must be accompanied by a $50 application fee and proof of publication (a copy of the legal notice) that the applicant has notified the public in the newspaper of largest circulation in the county or area where the activity is to take place, of his or her intent to operate under a Rule 6 Industrial Storm Water permit.
  3. The NOI letter must include (at least, but not limited to) the following information:
    1. Name of responsible corporate officer or duly authorized representative;
    2. Name and contact information of the individual who can provide assistance with information pertaining to the facility's permit;
    3. A brief narrative description of the industrial processes performed at the facility;
    4. Identification of the number and location of each outfall where Storm Water exposed to industrial activity will be discharged to a water of the state;
    5. The identification of past and present NPDES permits, if applicable;
    6. The latitude and longitude coordinates of the facility; and,
    7. The identification of the regulated MS4 entity receiving the storm water discharge, if applicable.

Storm Water Pollution Prevention Plan (SWP3)

Next, the facility must develop and implement a Storm Water Pollution Prevention Plan (SWP3), and submit a completed SWP3 Checklist Form (available on the IDEM Forms page) certifying to IDEM that such a plan is in place. The SWP3 Checklist Form must be signed by a qualified professional, and submitted to IDEM within 365 days of the submittal of the NOI letter. A "qualified professional" is a person "trained and experienced in storm water treatment techniques and related fields as may be demonstrated by state registration, professional certification, experience, or completion of coursework that enable the individual to make sound, professional judgments regarding storm water control or treatment and monitoring, pollutant fate and transport, and drainage planning."

The SWP3 itself must be retained at the facility, and made available for review during any on-site inspection. Periodically, the plan must be reviewed, and revised if changes at the facility alter conditions that could affect run-off.

If IDEM notifies a facility that their SWP3 is ineffective or deficient, a facility representative must make the required changes to the SWP3 and submit the amended plan within 60 days of the written notification.

Sampling Protocol

The facility must implement a comprehensive storm water monitoring plan that demonstrates that the Storm Water Pollution Prevention Plan (SWP3) is effectively limiting and reducing contaminates in storm water discharges. Some of the sampling requirements are:

  1. All samples are to be "grab samples" taken within the first 30 minutes of storm water discharges from a participation event of one-tenth, or more, inches of rain. Samples taken less than 72 hours after a previous precipitation event or run-off from melting ice or snow are not suitable for sampling purposes;
  2. The first grab sample(s) must be taken before beginning implementation of the SWP3. Afterward at least one sample must be taken each year, with a minimum of three months between sampling events;
  3. Facilities must test for a number of variables, including but not limited to: pH, oil and grease, nitrate plus nitrite nitrogen, phosphorous, chemical and carbonaceous biochemical oxygen demand and total suspended solids, as well as for any other pollutants that are reasonably expected to be present in the facility's storm water discharge;
  4. Sampling parameters must be compared from year to year from the second through the fifth year of permit coverage; and,
  5. Laboratory results must be reported to IDEM no later than 30 days after the sampling occurs.

Annual Report

All facilities regulated under Rule 6 must submit an annual report to IDEM in accordance with 327 IAC 15-6-7.5. The annual report should include the following information:

  1. Any changes to the original NOI letter;
  2. Any changes to the facility, the facility's operations or industrial activities;
  3. During the second through fifth years of permit coverage, a copy of the comparison of all sampling data results included in the facility's SWP3 and required under section 7(b)(9) of this rule; and,
  4. Any additional best management practices (BMPs) implemented, or corrective measures taken, as a result of sampling data results.

The annual report must contain information obtained during the previous year of regulation and be submitted initially no later than three hundred sixty-five (365) days from the initial NOI submittal date or the expiration date of the previous five (5) year permit term. Subsequent annual report submittals shall be provided no later than three hundred sixty-five (365) days from the previous report in years two (2) through five (5).

What to Expect

Once an application for a Rule 6 permit or conditional no exposure exclusion is submitted to IDEM, it generally will be processed by the IDEM Office of Water Quality within 30 days.

A Rule 6 permit must be renewed every 5 years, or for those who do not need a permit, the conditional no exposure exclusions also must be renewed every 5 years. NOI letters for new facilities are due at IDEM 90 days before operations begin. Renewal NOI letters should be submitted to IDEM 90 days before the existing permit expires. Neither Rule 6 permits, nor exclusions are transferable, so if the facility changes hands, the new owner/operator must reapply for a permit or exclusion within 60 days of the transfer.

A Notice of Termination (NOT) letter must be submitted to IDEM if the facility is:

  1. closing;
  2. transferring ownership;
  3. seeking a no exposure exclusion (only applicable for current Rule 6 general storm water permittees);
  4. directing all its storm water into a combined sewer system; or,
  5. claiming storm water does not have the potential to impact a water of the state (e.g., storm water run-off is directed to lined, on-site retention basins).

A termination request due to closure or ownership transfer must be submitted within 30 days of the date of closure or transfer. For facility representatives seeking a no exposure exclusion, the NOT request letter must be submitted with a completed
conditional no exposure certification form [PDF]. For facility representatives claiming that stormwater run-off is directed to a combined sewer system, the NOT request letter must be submitted with a certification letter from the responsible party of the combined sewer system, on responsible party letterhead.

Facilities operating under a Rule 6 permit are assessed a $100 annual fee every January.

Additional Information

To obtain additional information regarding storm water run-off associated with industrial activity, see the Industrial Storm Water Permitting webpage.

Other Useful Rule 6-related Documents

Questions may be directed to IDEM OWQ Rule 6 staff at (800) 451-6027, ext. 4-5029.

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