Summary

Stormwater regulations were published November 16, 1990, and called for stormwater permits under the Clean Water Act's National Pollution Discharge Elimination System (NPDES). Municipalities with separate storm sewer systems (also called MS4s) with populations of over 100,000 are subject to the requirements, as are most industries that discharge to MS4s or directly to waters of the United States.

Most industries are subject to the stormwater permitting requirements, unless they discharge stormwater to a combined (sewer and stormwater) municipal system. These industries may be subject to separate pretreatment requirements. Retail and commercial facilities, including the parking lots and administrative sections of industries are not subject to this phase of the stormwater regulations.

Industries related to transportation and those likely to store large amounts of raw materials outside are subject to the most intensive requirements, including stormwater sampling. Most other industries must only file if they have outside storage of materials. If all storage and ancillary facilities are within the industries building, then the requirements do not apply (for now). Most of the affected industries can obtain general permits.

Summary of General Permit Requirements

The General Permit requirements called for most industries to file a Notice of Intent (NOI) in 1992 and then to file a Pollution Prevention Plan in 1993. The plan must then be updated every 3 years.

Background

Stormwater has become an increasingly important water quality issue since the late 1970s, when water quality around the country had improved from the treatment of municipal and industrial wastewater point sources of pollution. Studies done during the late 1970s and early 1980s indicated that non-point source pollution (diffuse sources) was now a major water quality problem.

Congress called for the regulation of municipal and industrial stormwater discharges in the Water Quality Act of 1987 (sometimes called the 1987 amendments to the Clean Water Act). The Act outlined the requirements and deadlines for regulatory action. EPA published the first codification regulations in January 1989, but was later sued for failure to meet all the requirements of the Act. A Consent Order established new deadlines for the stormwater rules. The April 1989 Consent Decree was then amended in July 1990 to revise deadlines.

The final stormwater regulations were published November 16, 1990. These regulations defined the permitting requirements for municipalities with populations of more than 100,000 and for industries. The regulation also defined three types of permits:

Individual - These permit applications are more detailed and difficult to prepare than the general permits. They are required for some types of industries and special situations where complex conditions preclude general permits.

Group - The group permits apply to similar industries in groups ranging from 10 upward. These permits had earlier deadlines and basically allowed representative sampling for 10% of the group, creating savings in some cases.

General - The general permits issued to date include the construction permit, permits for concentrated animal feeding operations, and general industrial permits. These permits involve the filing of a Notice of Intent, followed by a more detailed Pollution Prevention Plan.

Where Do You Fit In?

The industries described below are subject to the regulation:

industries subject to individual stormwater effluent limitations guidelines, new source performance standards, or toxic pollutant effluent standards under 40 CFR Subchapter N unless exempted,
facilities in SIC 24, 26, 28, 29, 311, 32, 33, 3441, and 373 (except 2434, 265, 267, 283, 285, and 323). These are generally industries such as sawmills, paper mills, basic chemical products, petroleum industries, tanners, glass/clay/stone manufacturers, iron smelters, fabricated metals, and shipbuilding,
facilities in SIC 10-14 (mineral industries with certain exceptions),
hazardous waste treatment, storage, or disposal facilities,
landfills, land application sites, and open dumps that have received any industrial wastes (wastes from any of the facilities described in this section, including sewage sludge),
recycling facilities, including metal scrap yards, battery reclaimers, salvage yards, and automobile junkyards, including SIC 5015 and 5093,
steam electric power generating facilities, including coal handling sites and coal piles,
transportation facilities classified as SIC 40, 41, 42, 43, 44, 45, and 5171 (except 4221-25) if they have vehicle maintenance shops, equipment cleaning operations, or airport deicing operations,
treatment works treating domestic sewage with a design capacity of 1.0 mgd or more or that are required to have an approved pretreatment program (excluding offsite beneficial sludge reuse),
all construction activities disturbing five or more acres,
facilities in SIC 20, 21, 22, 23, 2434, 25, 265, 267, 27, 283, 30, 31, 323, 34, 35, 36, 373) 37, 38, 39, 4221-25 (except 311, 3441, only if areas where material handling equipment or activities, raw materials, intermediate products, final products, waste materials, byproducts, or industrial machinery at these facilities are exposed to stormwater. These industries typically are operated mostly indoors within a confined facility, so if all raw and finished materials are stored within the facilities buildings, then these industries are not subject to the regulations.
Municipalities with a population of less than 100,000 that operate airports, uncontrolled sanitary landfills, or power plants also are subject to the requirements. Other industrial facilities operated by municipalities with a population of less than 100,000 may be subject to future rules under Phase II of the stormwater program.

Defining Stormwater

Stormwater means stormwater runoff, snow melt runoff, surface runoff and drainage. The outfall means a point source of discharge which can be nearly any collection point. Certain sources are excluded, for example, infiltration, street wash waters, return flows from agriculture, and discharges to ground waters unless there is a hydrologic connection between the groundwater and a nearby surface water. Non-discharging basins also are excluded from the regulation.

Who Must Monitor?

Only the specific industries listed below must conduct stormwater monitoring, unless specifically requested to monitor.

EPCRA Section 313 Facilities Subject to Reporting Requirements for Water Priority Chemicals
Primary Metal Industries (SIC 33)
Land Disposal Units/Incinerators/BIFs
Wood Treatment Facilities
Industrial Facilities with Coal Piles
Battery Reclaimers
Airports with over 50,000 flight operations/year
Coal-fired Steam Electric Facilities
Animal Handling/Meat Packing Facilities
Chemical and Allied Product Manufacturers/Rubber Manufacturers (SIC 28 and 30)
Automobile Junkyards
Lime Manufacturing Facilities
Oil-fired Steam Electric Power Generating Facilities
Cement Manufacturing Facilities and Cement Kilns
Ready-mix Concrete Facilities
Ship Building and Repairing Facilities

Monitoring parameters vary by industry, and sampling requirements are either semiannual or annual by industry. Most of these industries retain the monitoring records onsite, but some must report annually.

Special Permit Conditions

There are two special conditions on all general permits, including a prohibition of non-stormwater discharges and procedures in the event of a release of a reportable quantity of hazardous substances and oil.

Non-stormwater Discharges

Discharges of all non-stormwater flows are prohibited, except flows from fire fighting and certain flows that have been identified in the pollution prevention plan described below.

The flows that may be allowed if described in the plan include:

fire hydrant flushings,
potable water sources, including water line flushings,
irrigation drainage,
lawn watering,
routine external building washdown without detergents,
pavement washwaters where spills or leaks of toxic or hazardous materials have not occurred (unless all spilled material has been removed) and where detergents are not used,
air conditioning condensate,
springs,
uncontaminated groundwater, and
foundation or footing drains where flows are not contaminated with process materials such as solvents that are combined with stormwater discharges associated with industrial activity.

Reportable Quantity Releases of Hazardous Substances and Oil

If a permitted stormwater discharge contains a hazardous substance or oil in an amount equal to or higher than the reporting quantity in 40 CFR 110, 117, and 302, the discharger must:

Notify the National Response Center
Modify the Stormwater Pollution Prevention Plan within 14 calendar days to provide a release description, including dates and circumstances.

A written description of the release also must be submitted to EPA within 14 calendar days. Facilities with more than one anticipated discharge of this type per year must submit notification for the first event of the calendar year, describe the events and identify measures to reduce the releases in the Pollution Prevention Plan.

The Pollution Prevention Plan

All of the industries subject to the rules must develop and implement a stormwater pollution prevention plan.

Baseline Requirements

The baseline requirements for all industries include:

The development of a Pollution Prevention Team to prepare the plan and assist the plant manager in its implementation.
Assess and describe potential pollution sources, including the site's drainage characteristics compared to material storage, fueling, or other areas of industrial activity. It also must include an inventory of exposed materials and a list and description of significant spills and leaks in the past three years. It also requires a certification that discharges from the site have been tested or evaluated for non-stormwater discharges, plus a description of any such sources. The description also must include sampling data and collection and analysis details. Finally, the description should include an assessment of the risk potential and potential pollutant sources.
Measures and controls must then be developed, including pollution prevention measures, best management practices, and other controls for the facility. These should include, minimally, good housekeeping practices, preventive maintenance measures, spill prevention and response procedures, inspection procedures, employee training, recordkeeping and internal reporting procedures, sediment and erosion control, and management of runoff.
The plan also must describe the Comprehensive Site Compliance Evaluation developed on the basis of site inspections.

Extra Requirements If You Report Under EPCRA 313

Section 313 facilities must address their storage and use of Section 313 chemicals in more detail, including special containment, drainage control, and/or diversionary structures to prevent rainwater contact with 313 chemicals. Liquid storage areas have several special priority area requirements, as do other material storage areas and any other areas where loading/unloading or other handling occurs.

Salt Piles
Any salt storage facilities must be covered within three years of the permit if the runoff from these piles discharges to waters of the United States. If the runoff is reused in other processes or the discharge is subject to a separate National Pollution Discharge Elimination System (NPDES) permit, a stormwater permit is unnecessary.

Discharges to MS4s > 100,000
Any industrial discharger to a large or medium municipal storm sewer system (MS4) must submit a signed copy of their Notice of Intent (NOI) to the MS4 operator, and must comply with the MS4's municipal stormwater management program.

Coal Piles
Coal pile runoff is limited to 50 mg/l total suspended solids and a pH range of 6.0-9.0, and must meet this limitation within three years of the permit.

Stormwater General Permits for Construction Issued

Final NPDES general permits for stormwater discharges from construction sites were published in a September 9, 1992 Federal Register notice. The general permits cover stormwater discharges associated with industrial activity from construction sites that disturb more than five acres.
EPA defines the term "stormwater discharge associated with industrial activity" to include stormwater discharges from construction activities (including clearing, grading, and excavation activities) that disturb five or more acres of total land area, including areas that are part of a larger common plan of development or sale.

Sites of less than five acres were removed from the Phase I rule by the courts in 1992, but regulated in Phase II of the rule promulgated Dec. 8, 1999.

Summary

For authorization under the general permit, discharges must complete a NOI and comply with the terms of the permit. The permit terms include the preparation of a site-specific stormwater pollution prevention plan at least two days prior to the commencement of construction activities for other projects.

Controlling Stormwater Pollutants

The general permit describes three major types of controls, including sediment and erosion controls, stormwater management measures, and housekeeping best management practices (BMPs).

Sediment and Erosion Controls

Sediment and erosion controls include two major classes of controls: stabilization practices and structural practices. Stabilization practices may include temporary or permanent seeding, mulching, vegetative buffer strips, and protection of trees. Structural practices may include work efforts such as earth dikes, silt fences, drainage swales, sediment traps, check dams, level spreaders, subsurface drains, pipe slope drains, temporary storm drain divergences, storm drain inlet protection, rock outlet protection and other controls.

Stormwater Management

Stormwater management measures include onsite infiltration, flow attenuation by vegetation or natural depressions, outfall velocity dissipation devices, retention structures/artificial wetlands, and water quality detention structures.

Best Management Practices

Certain housekeeping Best Management Practices also are described, including designating areas for equipment maintenance and repair and providing waste receptacles, locating equipment washdown areas onsite with control of washwater, protected storage areas for potentially toxic materials and adequately maintained sanitary facilities.

Notice of Intent

The NPDES general permits for stormwater require that dischargers submit a NOI before beginning construction. By submitting the NOI, an individual permit is not required unless EPA specifically notifies the discharger. Work is authorized to begin two days after the date that the NOI is postmarked unless EPA notifies the discharger otherwise.

The NOI includes fairly simple information such as mailing addresses, site owners and operators, names of receiving waters or municipal storm sewers, permit numbers of other permits, an indication of existing sampling data (although the data is not submitted), a project start date and completion date estimate, the number of acres onsite where soil will be disturbed, and a certification that a stormwater pollution prevention plan has been prepared in accordance with the permit and that it complies with approved state or local sediment and erosion plans or stormwater management plans or permits. The stormwater management plan is not submitted with the NOI.

Stormwater Pollution Prevention Plan

The plan itself includes a site description and a description of the site controls, which are to include erosion and sediment controls, stormwater management measures, a specified set of other controls, and any local sediment and erosion control plans or stormwater management plans. The maintenance of controls also must be identified and the inspection procedures must be provided showing that certain areas will be inspected on a specific schedule.

Allowable Non-Stormwater Discharges

Certain non-stormwater discharges, such as processed wastewaters or discharges from portable toilets are not authorized under the general permit. Yet, some non-stormwater discharges are allowed. These include discharges from fire fighting activities, fire hydrant flushings, waters used to wash vehicles or control dust to minimize offsite sediment tracking, potable water sources (including water line flushing), irrigation drainage from watering vegetation, routine exterior building washdown that does not use detergents, pavement wash waters where there are no spills or leaks of toxic or hazardous materials, air conditioning condensate, springs, uncontaminated groundwater (including dewatering groundwater infiltration), and foundation or footing drains where flows are not contaminated with process materials such as solvents. Each of these must be identified in the pollution prevention plan along with measures to control pollution if these discharges are to be allowed.

If a release containing a hazardous substance in an amount equal to, or in excess of, a reporting quantity occurs, the permittee must notify the National Response Center, notify the appropriate EPA regional office, and modify the stormwater pollution prevention plan to identify measures to prevent the reoccurrence of such releases.

Defining the Operator

EPA defines the operator as the party or parties that either individually or taken together meet the following two criteria:

they have operational control over the site specifications (including the ability to make modifications in the specifications), and
they have the day-to-day operational control of those activities at the site necessary to insure compliance with plan requirements and permit conditions.

EPA notes that in many instances, more than one party will have to submit an NOI for the same project to satisfy both criteria. Additionally, all contractors and subcontractors that will implement measures identified in the plan must be identified in the plan and must certify that they understand the terms and conditions of the permit. Subcontractors need only certify their knowledge of permit requirements and do not have to submit an NOI separately.

Final Stabilization

Final stabilization is defined in the general permit to mean that all soil disturbing activities at the site have been completed, and that a uniform perennial vegetative cover with a 70% density of cover for the area has been established or that equivalent stabilization measures have been employed. The 70% criteria is the minimum vegetation density, not the portion of the site to be stabilized. Equivalent stabilization measures might include situations where geo-textiles and/or mulches are used to stabilize a site until vegetation is established.

Stabilization measures must be initiated as soon as practicable, but in no case more than 14 days after construction activity on a portion of the site has temporarily or permanently ceased. Three exceptions include:

where construction activities will resume within 21 days on that portion,
where the initiation of stabilization measures is precluded by snow cover, and
arid areas (0 - 10 inches average annual rainfall) and semi-arid areas (10 - 20 inches average annual rainfall) where the initiation of stabilization measures is precluded by seasonal arid conditions.

In these cases stabilization measures must be initiated as soon as practicable.

Inspections

Disturbed areas, areas used for storage of materials exposed to precipitation, erosion and sediment control measures identified in the plans, accessible discharge locations or points, and locations where vehicles enter or exit the site are all required to be inspected once every seven calendar days and within 24-hours of the end of a storm of 0.5 inches or more rainfall.

For more information on stormwater permits, contact us at 800-725-2550.