The Arizona Department of Environmental Quality (ADEQ) has finalized the new 2013 Construction General Permit (CGP) which will become effective Monday, June 3, 2013. According to ADEQ, existing operators covered by the 2008 CGP are required to update their SWPPPs and be in compliance with the new permit as of that date, but to not need to reapply for permit coverage. Beginning on that date, operators of new projects requiring coverage must apply under the new permit. ADEQ expects to send an update and reminder approximately two weeks before the implementation date.
As background, US EPA finalized Effluent Limitations Guidelines and New Source Performance Standards for the construction and development industry ( “C&D rule”) on December 1, 2009. The C&D rule became effective on February 1, 2010, and include a suite of non-numeric effluent limitations that apply to all permitted construction sites. The non-numeric effluent limits include requirements for:
- Erosion and Sediment Controls;
- Soil Stabilization;
- Pollution Prevention Measures;
- Prohibited Discharges; and
- Protection of Surface Outlets.
ADEQ’s 2013 CGP includes language that implements US EPA’s C&D rule non-numeric limits. The permit also includes water quality-based requirements for construction sites discharging stormwater to waters requiring additional pollutant control.
US EPA’s C&D rule requirements include (1) non-numeric effluent limitations that apply to all permitted discharges from construction sites , and (2) a numeric effluent limit for turbidity (which is the subject of an indefinite stay) that applies to certain larger sites. USEPA has issued the stay for the numeric limit for turbidity so that the limit can be recalculated. Until a new limit is promulgated, USEPA and authorized states (including Arizona) are not required to incorporate a numeric turbidity limitation into their permits.
The C&D rule’s non-numeric effluent limitations are incorporated into the AZPDES 2013 stormwater Construction General Permit (2013 CGP). The C&D rule contains non-numeric effluent limitations that require the operator to minimize the discharge of pollutants including the prevention of the mobilization and discharge of sediment, turbidity, and other sediment-bound pollutants, such as metals and nutrients, and to prevent or minimize the exposure of stormwater to construction materials, debris, and other sources of pollutants on construction sites. In addition, these non-numeric effluent limitations limit the generation of dissolved pollutants, such as nutrients, organics, pesticides, herbicides and metals that may be present naturally in the soil on construction sites, such as arsenic or selenium, or may have been contributed by previous activities on the site such as agriculture or industrial.