New Effluent Limit Rules Going Into Effect One State at a Time
One state at a time, the U.S. Environmental Protection Agency's (EPA) new Effluent Limit Guidelines for builder and developer storm water management permits are now beginning to take effect.
North Carolina is the first state to officially recognize the rule, which tightens restrictions on residential development of all sizes and, for the first time, includes a strict numeric limit on the turbidity — or amount of sediment — of water that flows from larger construction sites after a rainstorm.
However, because the state was in the middle of its permit process when the new ELG was finalized on Feb. 1, it won’t be required to add the ELG language for 18 months, in August 2011.
To keep their storm water permitting authority current, every five years state environmental offices are required to submit any proposed changes to their permitting process to the EPA. States renewing permits after the guidelines’ effective date of Feb. 1, need to take the new guidelines into consideration.
The new ELGs set a “technology floor” that all permittees are required to meet. The states can adopt provisions that are more onerous than this federal minimum if they so choose, such as a lower turbidity limit or a more aggressive implementation timeline.
The agency released the ELG proposal in 2008 under a court order after a lawsuit filed by an advocacy group argued that builders — whose “discharges” under the Clean Water Act are the result of rainfall and sediment running off the construction site — should be treated like commercial and industrial enterprises, which discharge water and chemicals via pipelines.
The guidelines set out requirements without regard to the type of soil on the job site and how likely it is to absorb excess rainwater or regard to the natural turbidity of nearby streams or other water bodies.
The rules also require stepped-up state enforcement, but the EPA has not yet issued guidance on how to monitor compliance or how to pay for the additional administrative and inspection costs.
Further, the additional requirements are more difficult — and in some cases impossible — to meet on smaller lots and in urban redevelopment, severely hampering “smart growth” projects and transit-friendly building.
Other states whose permits will expire soon include Maine, Connecticut, Tennessee, Mississippi, Washington and Oregon. South Dakota slipped in just before the deadline and thus avoided the additional ELG language; Pennsylvania took a similar approach to North Carolina and renewed for two years only.
As ELGs are added into different state permits, home builders associations will need to stay involved in the process. EPA’s Web site link is http://cfpub.epa.gov/npdes/stormwater/cgp.cfm .
The ELG establishes the minimum control requirements that must be met by everyone who needs a National Pollutant Discharge Elimination System (NPDES) construction storm water permit issued by the EPA or an authorized state.
Operators have to comply with the ELG requirements once they are incorporated into the EPA’s or a state’s NPDES construction general permit.
The EPA has established a four-year timeframe for nationwide implementation to provide the states and the regulated community sufficient time to develop compliance processes and a full understanding of the new requirements.
With ELGs, all construction activities that require an NPDES storm water permit must meet certain requirements.
Erosion and sediment control should be designed, installed and maintained to control storm water volume, velocity and peak flow rates. It also must minimize the amount of soil exposed and the disturbance of steep slopes, soil compaction and the amount of sediment discharge.
It also must be designed to direct storm water to vegetated areas, maximize infiltration and include natural buffers around surface waters wherever possible.
Click here for a fact sheet detailing other additional pollution prevention measures that are required.
All construction activities that disturb 20 or more acres of land at one time must meet a daily average turbidity limit of 280 Nephelometric Turbidity Units (NTUs) by August, 2011. That limit will be expanded to projects disturbing 10 or more acres at a time in February 2014.
The turbidity effluent limit must only be met for the two-year, 24-hour storm event. Compliance with the numeric limit will require regular sampling and monitoring. These requirements will be defined by the state permitting authorities.
Unlike previous ELGs in which the EPA identified a model technology that had been shown to meet the established limits, in this instance, the agency has left the determination of what methodology to use to the permit holder.
The agency says it believes the limit can be met through the use of a combination of best management practices including polymer-aided settling techniques such as chitosan and Polyacrylamide (PAM); and site planning practices, such as limiting the amount of land disturbed at any one time or phasing construction activities.
Because the EPA has limited data on the effectiveness of these techniques, it is not known whether any of them will consistently meet the 280 NTU limit. As a result, builders and developers will likely have to go through a period of trial and error to determine which combination of control measures will achieve the required discharge limitation for each project.
In fact, the EPA cited the need for adjusting, modifying and revising the new control techniques as one of the primary reasons why it delayed implementation of the ELGs for 18 months.
The link to the ELG section on the EPA’s Web site is: http://www.epa.gov/waterscience/guide/construction.
For more information, e-mail Calli Schmidt at NAHB, or call her at 800-368-5242 x8132.
Are You Ready for a Visit From the EPA?
“Storm Water Permitting: A Guide for Builders and Developers,” available through BuilderBooks.com, provides a starting point for builders and developers to use in locating and understanding storm water permitting requirements.
The publication has been prepared to help builders comply with the U.S. Environmental Protection Agency's stormwater requirements, and includes information on state permitting programs and more than 50 of the most commonly used Best Management Practices.
Also included are tips on compliance, including how to handle visits from inspectors.
To view or purchase this guide online, click here, or call 800-223-2665.