Stormwater runoff from construction sites has been an area of environmental regulation that received only passing attention until sometime around 2004. In that year, EPA inspected a large retail facility, found multiple violations and imposed heavy fines. Since then, EPA has expended significant resources to ensure compliance with the regulations.
In 2008, EPA determined that the existing regulations were insufficient and proposed additional regulations. The proposed rules were put out for public comment and on November 23, 2009, EPA handed down new, technology-based guidelines. For developers and home builders, it wasn’t good news. The new regulations, found at 40 C.F.R. Part 450, impose two new requirements:
1. Construction site owners and operators that disturb one or more acres must use best management practices to ensure that soil disturbing during construction activities will not pollute nearby waters;
2. Construction sites that disturb 20 acres or more at one time (later being reduced to 10 acres) must monitor discharges from the site and prevent discharges that exceed 280 nephelometric turbidity units (NTUs) from leaving the site.
The second requirement sets out, for the first time, a numeric standard on discharge from construction sites. EPA’s original proposal was to have a numeric limit of 13 NTUs, which is a very clean discharge. During the comment period, EPA was informed that a limit of 13 NTUs would increase the cost of construction by $15,000 to $45,000 per acre. The final standard of 280 NTUs, while more lenient, will add some significant costs to new construction.
A few items of note about the 280 NTU limit:
1. If the rainfall is in excess of the 2-year, 24-hour storm event, then the limit does not apply. In effect, such a large rainfall is treated as a bypass event;
2. If less than 20 acres (or, later, 10 acres) is disturbed at one time, then the limit does not apply. As soon as a developer goes over 20 acres of open area, the limit kicks in until there is a drop below 20 acres, in which case the limit no longer applies;
3. In counting the 20 (or 10) acres, the develop must count all of the acres within the same common plan of development or sale even if the open acres are not contiguous;
4. The developer can test the effluent multiple times over the course of the day, but the average of those test results must be less than 280 NTUs to avoid a violation;
5. The BMP requirement applies at all times and is not tied to the 280 NTU limit.
Because the new requirements are a significant departure from the existing regulations, they will be phased in:
1. Construction sites that disturb 20 acres or more at one time will need to monitor beginning 18 months after the effective date of the rule;
2. Construction sites that disturb 10 acres or more at one time will need to monitor beginning four years after the effective date of the rule.
For states that have not been delegated NPDES authority and that use the federal storm water construction permits (Idaho, Massachusetts, New Hampshire, New Mexico and the District of Columbia), this means that the monitoring will begin August 1, 2011, and February 1, 2014. States that have been granted authority and periodically receive approval for the program will have a delay of the effective date. In the past, EPA has allowed the states to phase in new rules in accordance with their permit renewal dates. For example, Iowa’s storm water construction permit will be renewed on or about October 1, 2012. Therefore, Iowa’s compliance dates for the new requirements could be April 1, 2014, and October 1, 2016. We’ll have to wait to see if this interpretation is allowed for these new rules.
The changes imposed by the new rule couldn’t have come at a worse time, but, to some extent, EPA had no choice. The rule changes were in response to a court order that compelled EPA to makes changes by December 1, 2009. The question that remains is whether the new rules are sensible. That question is for another post.
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