Industrial Storm Water and Conditional “No Exposure” Exclusion

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The information provided is intended as a brief and broad overview of the industrial storm water NPDES permitting program in Hawaii as administered by the Department of Health, Clean Water Branch (CWB) and is not to be construed as comprehensive statements of applicability requirements. The information provided is not a substitute for applicable law, policy, or official agency determinations or statements.

The information is intended to provide a basic understanding of Hawaii’s industrial storm water NPDES program and most likely will not address all potential projects/facilities that have situations and conditions unique to that project/facility. If you believe that your project or facility may need to apply for and obtain industrial storm water NPDES permit coverage, it is your responsibility to obtain any additional information, clarification, or additional guidance. If your project or facility needs industrial storm water NPDES permit coverage, it is your responsibility to apply for and obtain NPDES permit coverage prior to discharge or in accordance with any applicable application timelines.

Applicability of Industrial Storm Water NPDES Permitting
Discharges of storm water associated with industrial activity are required to either apply for and obtain NPDES permit coverage or a Conditional “No Exposure” Exclusion. Facilities that fall into categories defined in 40 CFR §122.26(b)(14)(i) – (ix) and (xi) are considered to be engaging in “industrial activity” for the purposes of industrial storm water NPDES permitting. NPDES permit coverage or an exclusion to NPDES permit coverage is required when a facility is engaging in a regulated “industrial activity.”

If a regulated facility is able to meet certain requirements that ensure that no industrial pollutants are discharged in storm water from the facility, the facility may apply for a Conditional “No Exposure” Exclusion in lieu of NPDES permit coverage. In general, the requirements to be eligible for a Conditional “No Exposure” Exclusion are that all industrial activities at the facility and other industrial pollutant sources (e.g., storage tanks, stockpiling areas, maintenance activities, etc.) are either under cover or contained/sealed in such a way that it will not be in contact with storm water. For more information see the Conditional “No Exposure” Exclusion Requirements section of this page.

Regulated Industrial Entities
See below for a list of regulated industrial entities. Some designations are based on a facility’s Standard Industrial Classification (SIC) code. For more information on SIC codes and how to find your facility’s code, see the How do I find my SIC and NAICS Codes section.

Click here to download a pdf copy of this list.

Subpart Description
(i) Facilities subject to storm water effluent limitations guidelines, new source performance standards, or toxic pollutants effluent standards under 40 CFR, Subchapter N [except facilities with toxic pollutant effluent standards which are exempt under category (xi) in 40 CFR 122.26(b)(14)].
(ii) Facilities Classified as:
SIC 24 (except 2434) Lumber and Wood Products
SIC 26 (except 265 & 267) Paper and Allied Products
SIC 28 (except 283 & 285) Chemicals and Allied Products
SIC 29 Petroleum and Coal Products
SIC 311 Leather Tanning and Finishing
SIC 32 (except 323) Stone, Clay, and Glass Products
SIC 33 Primary Metal Industries
SIC 3441 Fabricated Structural Metal
SIC 373 Ship and Boat Building and Repairing
(iii) Facilities including active or inactive mining operations; oil and gas exploration; production, processing, or treatment operations; or transmission facilities that discharge storm water contaminated by contact with or that has come into contact with any overburden, raw material, intermediate products, finished products, byproducts or waste products located on the site of such operations. Inactive mining operations are mining sites that are not being actively mined, but which have an identifiable owner or operator; inactive mining sites do not include sites where mining claims are being maintained prior to disturbances associated with the extraction, beneficiation, or processing of mined materials, nor sites where minimal activities are undertaken for the sole purpose of maintaining a mining claim.
SIC 10 Metal Mining
SIC 11 Anthracite Mining
SIC 12 Coal Mining
SIC 13 Oil and Gas Extraction
SIC 14 Nonmetallic Minerals, except Fuels
(iv) Hazardous waste treatment, storage, or disposal facilities, including those that are operating under interim status or a permit under Subtitle C of the Resource Conservation and Recovery Act (RCRA).
(v) Landfills, land application sites, and open dumps that receive or have received any industrial wastes (waste that is received from any of the facilities described under this subsection) including those that are subject to regulation under Subtitle D of the Resource Conservation and Recovery Act (RCRA).
(vi) Facilities involved in the recycling of material, including metal scrapyards, battery reclaimers, salvage yards, and automobile junkyards, including, but limited to those classified as:
SIC 5015 Motor Vehicle Parts, Used
SIC 5093 Scrap and Waste Materials
(vii) Steam electric power generating facilities, including coal handling sites.
(viii) Transportation facilities which have vehicle maintenance shops, equipment cleaning operations, or airport de-icing operations. Only those portions of the facility that are either involved in vehicle maintenance (including vehicle rehabilitation, mechanical repairs, painting, fueling, and lubrication), equipment cleaning operations, or airport de-icing operations, or which are otherwise identified under 40 CFR §122.26(b)(14)(i)-(vii) or (ix)-(xi) are associated with industrial activity.
SIC 40 Railroad Transportation
SIC 41 Local and Suburban Transit
SIC 42 (except 4221 – 25) Motor Freight and Warehousing
SIC 43 U.S. Postal Service
SIC 44 Water Transportation
SIC 45 Transportation by Air
SIC 5171 Petroleum Bulk Stations and Terminals
(ix) Treatment works treating domestic sewage or any other sewage sludge or wastewater treatment device or system, used in the storage, treatment, recycling, and reclamation of municipal or domestic sewage, including land dedicated to the disposal of sewage sludge that are located within the confines of the facility, with a design flow of 1.0 mgd or more, or required to have an approved pretreatment program under 40 CFR Part 403. Not included are farm lands, domestic gardens, or lands used for sludge management where sludge is beneficially reused and which are not physically located in the confines of the facility, or areas that are in compliance with Section 405 of the CWA.
(xi) Facilities which are not otherwise included in 40 CFR §122.26(b)(14)(ii)-(x).
SIC 20 Food and Kindred Products
SIC 21 Tobacco Products
SIC 22 Textile Mill Products
SIC 23 Apparel and Other Textile Products
SIC 2434 Wood Kitchen Cabinets
SIC 25 Furniture and Fixtures
SIC 265 Paperboard Containers and Boxes
SIC 267 Converted Paper and Paper Board Products (except containers and boxes)
SIC 27 Printing and Publishing
SIC 283 Drugs
SIC 285 Paints, Varnishes, Lacquer, Enamels
SIC 30 Rubber and Miscellaneous Plastic Products
SIC 31 (except 311) Leather and Leather Products
SIC 323 Products of Purchased Glass
SIC 34 (except 3441) Fabricated Metal Products
SIC 35 Industrial Machinery and Equipment, except Electrical
SIC 36 Electronic and Other Electric Equipment
SIC 37 (except 373) Transportation Equipment
SIC 38 Instruments and Related Products
SIC 39 Miscellaneous Manufacturing Industries
SIC 4221 Farm Products Warehousing and Storage
SIC 4222 Refrigerated Warehousing and Storage
SIC 4225 General Warehousing and Storage

How do I Find my SIC and NAICS Codes?
You can find the SIC code(s) for your facility at:

SIC codes were developed by the Department of Commerce, Bureau of Census to collect, tabulate and analyze data by business type. SIC codes use a four-digit numbering system to classify a business by its primary activity. For example: SIC code 7539 identifies “automotive repair shops” and SIC code 2521 identifies “wood office furniture manufacturing.” In 1997 the Bureau of Census replaced the SIC codes with North American Industry Classification System (NAICS). This means that old SIC codes don’t match directly with the new NAICS codes.

Some environmental regulations, for example the National Pollutant Discharge Elimination System (NPDES) industrial storm water requirements, continue to reference the SIC codes. In addition, some permit applications, registrations, and reports require that the business be identified by its SIC code, so, it is important that you have information on both your SIC and NAICS codes. You may already have your NAICS code on your tax forms. If you do, you can go to, find the most recent NAICS to SIC spreadsheet (under concordances), and cross-reference the corresponding SIC code. (Note that an ISIC is not the same as SIC, so be careful when selecting the appropriate spreadsheet).

If you don’t have an NAICS code to reference, go to and you can use the look up tools to help you find an appropriate NAICS code for your company. Then use the above crosswalk document to cross-reference your SIC code.

Note that for the Clean Water Branch NPDES forms you will need to input both your NAICS and corresponding SIC codes.

Industrial Storm Water Sector
To get coverage under the industrial storm water general permit, you will need to identify your facility’s industrial sector(s). Your facility’s industrial sector(s) determine what sector-specific discharge requirements apply to your facility. Sector-specific requirements may include additional information required to be included in your Storm Water Pollution Prevention Plan (SWPPP), modified inspection schedules, additional sampling requirements, etc. The industrial storm water sector is primarily based on the SIC code for the facility and can be determined by looking at the SIC code to industrial storm water sector table in Part 9 of the industrial storm water general permit (HAR Chapter 11-55 Appendix B ).

Click here for a quick visual guide on how to find your industrial storm water sector.

Conditional “No Exposure” Exclusion Requirements
Discharges composed entirely of storm water are not storm water discharges associated with industrial activity if there is “no exposure” of industrial materials and activities to rain, snow, snowmelt and/or runoff. “No exposure” means that all industrial materials and activities are protected by a storm resistant shelter to prevent exposure to rain, snow, snowmelt, and/or runoff. Industrial materials or activities include, but are not limited to, material handling equipment or activities, industrial machinery, raw materials, intermediate products, by-products, final products, or waste products. Material handling activities include the storage, loading and unloading, transportation, or conveyance of any raw material, intermediate product, final product or waste product.

Also as a reference, EPA Guidance Manual for Conditional Exclusion from Storm Water Permitting Based on “No Exposure” of Industrial Activities to Storm Water is provided for your information, however, please note that the CWB is the authorized NPDES Permitting authority for the State of Hawaii and the entire EPA document is for reference only (i.e., do not submit forms in this EPA Guidance Manual).

To qualify, the operator of the discharge must:

  • Provide a storm resistant shelter to protect industrial materials and activities from exposure to rain, snow, snow melt, and runoff;
  • Allow the DOH to inspect the facility to determine compliance with the “no exposure” conditions (as necessary including after granting of the exclusion, subject to DOH discretion);
  • Allow the DOH to make any “no exposure” inspection reports available to the public upon request; and
  • For facilities that discharge through a Municipal Separate Storm Sewer System (MS4), upon request, submit a copy of the certification of “no exposure” to the MS4 operator, as well as allow inspection and public reporting by the MS4 operator.

Storm resistant shelter is not required for:

  • Drums, barrels, tanks, and similar containers that are tightly sealed, provided those containers are not deteriorated and do not leak (“Sealed” means banded or otherwise secured and without operational taps or valves);
  • Adequately maintained vehicles used in material handling; and
  • Final products, other than products that would be mobilized in storm water discharge (e.g., rock salt).

Please note that this exclusion has the following limitations:

  • Storm water discharges from construction activities are not eligible for this conditional exclusion (please see our Construction Storm Water General Permit FAQ for coverage of storm water from construction activities);
  • This conditional exclusion from the requirement for an NPDES permit is available on a facility-wide basis only, not for individual outfalls. If a facility has some discharges of storm water that would otherwise be “no exposure” discharges, individual permit requirements should be adjusted accordingly;
  • If circumstances change and industrial materials or activities become exposed to rain, snow, snow melt, and/or runoff, the conditions for this exclusion no longer apply. In such cases, the discharge becomes subject to enforcement for un-permitted discharge. Any conditionally exempt discharger who anticipates changes in circumstances should apply for and obtain permit authorization prior to the change of circumstances; and
  • DOH retains the authority to require permit authorization (and deny this exclusion) upon making a determination that the discharge causes, has a reasonable potential to cause, or contributes to an instream excursion above an applicable water quality standard, including designated uses.

Please see 40 CFR 122.26(g) for the full applicability requirements. If the facility can meet these requirements, you may apply for a Conditional “No Exposure” Exclusion.

To apply, go to the e-Permitting Portal at: and complete and submit a CWB “No Exposure” Certification Form.

How to Apply for Industrial Storm Water NPDES Permit Coverage
If there is an effective general permit for industrial storm water and the facility can comply with the general permit, it is recommended that you apply for general permit coverage. First you must determine whether the facility can comply with the general permit for storm water discharges associated with industrial activities. The general permit is in HAR Chapter 11-55, Appendix B, available at:

General permits are permits that the CWB issues that cover a specific category of discharge. These permits are not issued to any single discharger or legal entity, rather, it provides specific requirements and criteria for controlling potential pollution from the category of discharge and allows applicants to request coverage under the general permit. This request is called a Notice of Intent or NOI. To request coverage under a general permit, a facility must be able to provide all information required in the NOI and certify that the facility will comply with all applicable requirements specified in the general permit. Inability to comply with any applicable requirement in the general permit disqualifies the facility from coverage under the general permit.

To submit an NOI, go to the e Permitting Portal at: and use the form finder to find the CWB NOI Form. Follow all instructions on the form to complete and submit an NOI to the CWB. You will need to specify that you are requesting coverage under Appendix B.

If the CWB grants the facility general permit coverage, you will be issued a Notice of General Permit Coverage (NGPC). The NGPC is not the permit. The NGPC is a notice that the project is now covered under the General Permit, and must comply with its requirements (i.e., must comply with HAR Chapter 11-55, Appendix B).

Please note that if a facility is unable to comply with the requirements of the general permit and must have NPDES permit coverage, you must apply for an individual NPDES permit. To apply for an individual NPDES permit, go to the e-Permitting Portal and complete and submit a CWB Individual NPDES Form.