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Water Quality Division: Permits: Arizona Pollutant Discharge Elimination System (AZPDES) Multi-Sector General Permit (MSGP) 2010

Arizona Pollutant Discharge Elimination System (AZPDES) MSGP

To view the most updated information on MSGP items, visit our new website at AZPDES Industrial Stormwater Mining MSGP or AZPDES Industrial Stormwater Non-Mining MSGP.

The AZPDES MSGP permits (Mining and Non-mining) were signed December 20, 2010 and became effective February 01, 2011 and are currently administratively continued, pursuant to A.R.S. §49-255.01(M), eligible new stormwater dischargers may obtain coverage under the administratively continued MSGP by submitting an NOI through myDEQ.

Both AZPDES MSGP 2010 permits contain eight parts. Parts 1 through 7 describe the requirements that all operators must meet when seeking coverage under either of these permits. Part 8 describes the additional sector-specific requirements for industrial activities. A permittee need only comply with the additional requirements of Part 8 that apply to the sector(s) of industrial activity for that facility (i.e., these sector-specific requirements are in addition to the basic requirements of all facilities specified in Part 1 - 7 of the permit.)

Two-Page Sector-Specific Fact Sheets

  • Ship and Boat Building and Repairing Yards (Sector R) Questionnaire -- (PDF)
  • Air Transportation (Sector S) Questionnaire -- (Word)
  • Metal Fabrication/Plating (Sector AA) Questionnaire -- (Word)
  • Auto Salvage/Scrap Recycling (Sectors M & N) Questionnaire -- (Word)
  • Land Transportation and Warehousing (Sector P) Questionnaire -- (Word)
  • ADEQ's MSGP Overview

    The purpose of the stormwater permitting program; who should apply and how to apply for coverage; basic elements of a stormwater pollution prevention plan (SWPPP), including inspections, corrective actions, monitoring and reporting; brief coverage of the topic of no exposure; compare/ contrast the condition of no exposure with the "do not discharge" condition; the role of stormwater surface impoundments and drywells; and proposed MSGP fees.

    For additional information about the industrial stormwater permitting program, consult these links:

    The Multi-Sector General Permit (MSGP) is designed for discharges of stormwater from certain industrial sites that are of a non-construction nature. The MSGP is one large permit divided into numerous separate sectors. Each sector represents a different type of activity and is dependent upon its Standard Industrial Classification (SIC) code or narrative description.

    Facility operators can determine for themselves whether or not they are eligible for coverage under the MSGP. In most cases, the key is knowing your SIC code (see also 40 CFR 122.26(b)(14)). Be advised that the facility may be subject to the requirements of more than one sector if it has operations that can be described by other sectors.

    Locate your facility's primary SIC code on Table C – 1. If your SIC code can not be found on the table, search the table to determine if your facility's operation can be defined by a narrative description. If either a matching SIC code or narrative description can be found on the table, the facility is subject to the requirements of the MSGP.

    Example: Your SIC code is 4213 (non-local trucking). Searching category viii you find a SIC code match with number 42. Reading the narrative, you see that a permit is required only for the part of the facility that is involved in vehicle maintenance and equipment cleaning. However, you contract out for those services at another facility. Therefore, you can conclude that you do not need to apply for a stormwater permit at this time.

    The following is provided for informational purposes only, as a guide to facility operators applying for coverage under the MSGP 2010.

    • Discharges authorized by this permit must not cause or contribute to a violation of any applicable state water quality standard (18 A.A.C. 11).
    • SARA section 313 (Community Right to Know): Facilities with liquid storage areas for section 313 water priority chemicals must be operated to minimize discharges of such chemicals. Appropriate measures to minimize discharges of section 313 chemicals include provision of secondary containment for at least the entire contents of the largest tank plus sufficient freeboard to allow for the 25-year, 24-hour precipitation event; a strong spill contingency and integrity testing plan; and/or other equivalent measures.
    • Facilities subject to monitoring and reporting requirements must submit a discharge monitoring report form(s) and other required monitoring information.
    • Significant sources of non-stormwater include, but are not limited to, discharges that could cause or contribute to violations of Arizona water quality standards, and discharges that could include releases of oil or hazardous substances in excess of reportable quantities under section 311 of the Clean Water Act (CWA) (See 40 CFR 110.10 and 40 CFR 117.21) or section 102 of CERCLA (See 40 CFR 302.4).
    • The term "base flood elevation" is defined by Federal Emergency Management Agency (FEMA) as the height of the base (100-year) flood in relation to a specified datum, usually the National Geodetic Vertical Datum of 1929 of North American Vertical Datum of 1988. This is the elevation of the 100-year flood waters relative to "mean sea level."
    • The term "100-year flood" means the flood having a one percent chance of being equaled or exceeded in magnitude in any given year.
    • The term "100-year floodplain" means that area adjoining a river, stream or watercourse covered by water in the event of a 100-year flood.

    The No Exposure Exclusion

    As an alternative to operating under the MSGP, a facility operator certifies that the facility is not exposed to stormwater. The result of this certification is that the facility is excluded from the requirement to obtain a stormwater permit. This exclusion is not available to construction facilities. To obtain the exclusion, the no exposure certification form must be completed and an answer of "no" must be given to all questions in the form's exposure checklist. To maintain the exclusion, the form is required to be submitted every five years.

    A few terms are necessary to fully understand the purpose of the No Exposure Exclusion.

    • "No exposure" means that all industrial materials or 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.
    • "Storm resistant shelter" means: completely roofed and walled buildings or structures; structures with top covering but no side covering and temporary covers. The material under these shelters must not be subject to any stormwater run-on and not have any stormwater run-off.

    Certain items may be stored outside without the benefit of shelters and still meet the definition of no exposure. Tightly sealed drums, barrels, tanks and similar containers are not exposed if they do not have operational taps or valves. In this context, sealed means banded or otherwise secured. Any material added or removed from these containers constitutes exposure.

    Adequately maintained vehicles used in material handling are considered to be non-exposed. Examples would include trucks, automobiles, forklifts or other general purpose vehicles that are not industrial machinery and are not a source of pollutants. These vehicles, when awaiting maintenance, would also not be considered exposed as long as they are not leaking contaminants and are otherwise not a source of pollutants.

    Final products are eligible for the exclusion when they are stored outside as long as the product cannot be mobilized in stormwater. The principle to remember is that the final product must not be used to produce another product. If it can be used to produce another product, then the material is an intermediate product and is not eligible for the exclusion. For example, an aluminum tube manufacturer sells tubing to a lawn furniture manufacturer. The tube facility may not store the tubes outside and avail themselves of the exclusion because the tubes are used to make another product - the lawn furniture. However, the manufacturer of lawn furniture could store that product outside and benefit from the exclusion because the lawn furniture is a final product.

    Several points should be kept in mind when considering the no exposure option. The exclusion is intended to encompass the whole facility. Where exposure to industrial materials or activities exist at some but not all areas of the facility, the non-exposure exclusion is not allowed. If part, or all, of the facility becomes exposed, then permit coverage is required. Failure to maintain non-exposure status could result in an unauthorized discharge of stormwater and result in an enforcement action. The certification form is non-transferable. A new facility operator must complete, sign and submit a new form to claim the non-exposure exclusion. Upon submittal of the no exposure certification form, ADEQ may inspect the facility to determine compliance with the no exposure conditions. If the facility discharges to a MS4, the municipality may request a copy of the certification as well as conduct inspections. Finally, those facilities that were previously exempted as a result of non-exposure from the permitting requirements under Phase I of the stormwater program (those facilities meeting the description at 40 CFR 122.26(b)(14)(xi) (also called light industries)) are now required to submit the no exposure certification form to maintain their non-exposed status.