On Nov. 21, 2014, the Kentucky Division of Water (DOW) finalized its KPDES General Permit for stormwater discharges associated with construction activities. The Permit became effective Dec. 1, 2014, and will expire on Nov. 30, 2019.

As discussed in prior issues of the Environmental Letter, the KPDES General Permit, KYR10 renews the prior General Permit, which had expired on July 31, 2014.

The most important change from the prior version of the General Permit is that it now also is applicable to construction activities that disturb greater than one-acre that will discharge to waterbodies that support cold water aquatic habitat or endangered species, as well as to Outstanding State Resource Waters (OSRWs).

Previously, an individual KPDES Permit was required for discharges to special use waters. For construction sites that discharge to such special use waters, the General Permit imposes a 50-foot buffer zone requirement, as compared to the 25-foot buffer zone that applies to facilities that do not discharge to such special use waters.

In response to comments from EPA, the Division also clarified certain aspects of the Permit to ensure it was consistent with EPA’s effluent limitation guidelines for the construction and development point source category at 40 CFR Part 450. These revisions to the Permit include the following:

  • The design, installation, and maintenance of erosion and sediment controls must address factors such as the amount, frequency, intensity, and duration of precipitation events, as well as soil characteristics present onsite.
  • Unless infeasible, natural buffers are to be provided and maintained around receiving waters, and infiltration of stormwater is to be maximized.
  • The term “infeasible” has been defined in the Fact Sheet as “not technologically possible, or not economically practicable in light of best industry practices.” The term “practicable” is not defined in the Fact Sheet.
  • Permittees are to minimize soil compaction and, unless infeasible, preserve topsoil, except in areas where the intended function dictates compaction or removal/disturbance of topsoil.
  • Construction dewatering, including dewatering of trenches and excavations, must be properly managed by appropriate controls.
  • The permittee must minimize the discharge of wastewater from equipment and vehicle washing and other wash waters, and the wash waters must be treated in a sediment basin or alternate control that provides equivalent treatment.
  • The revised Permit expands upon the list of wash-out and clean-out waters that are prohibited, such as those from clean-out of containers for stucco, paint, and curing compounds.

The renewed General Permit requires an electronic Notice of Intent (NOI) to be submitted a minimum of seven days before the proposed date for commencement of construction activities. For ongoing projects, DOW has extended coverage under the Permit for a period of one year from the effective date of the renewal Permit. Ongoing projects include those that obtained permit coverage under the prior version of KYR10 on or before July 31, 2014. For ongoing projects, existing Storm Water Pollution Prevention Plans (SWPPPs) and Best Management Practices (BMPs) are considered in compliance with the requirements of the renewal Permit, but DOW reserves the right to require SWPPPs and BMPs to be upgraded where necessary to protect water quality.