BALTIMORE, MD (December 17, 2008)–Today the Maryland Department of the Environment (MDE) issued its “final determination” for a general permit for stormwater related to all construction activities disturbing one or more acres. New conditions include increased public notification and participation as well as monitoring and plan review, and address several critical elements of site design and erosion and sediment controls in plans. The new permit is an important step toward involving the public and cleaning up local waterways to restore the Chesapeake Bay by reducing the amount of sediment runoff.
Through a series of public stakeholder meetings, MDE considered changes to the permit provisions and incorporated numerous suggestions to improve sediment control practices to ensure that water quality standards are achieved. Because some important changes must be incorporated into technical standards, MDE will review and modify the State’s erosion and sediment control standards in 2009.
At the November 24, 2008, public hearing on this general permit, some questions were raised about requiring numerical turbidity limits for all construction sites.
In response to those questions, the following is a statement from MDE Deputy Secretary Bob Summers:
The Department of the Environment reviewed a considerable amount of information about effluent limitations related to stormwater and requirements developed by other states. A great variety of approaches are being taken. It is often not possible to remove particles such as clays and fine silts contained in stormwater discharges from construction sites using conventional stormwater management practices, such as silt fence and sediment basins. In order to achieve a numeric limit for turbidity, many sites would need to use chemical treatment and filtration of their stormwater discharges. These methods cause environmental and implementation issues that need further evaluation. Incorporating a turbidity requirement in the general permit would also create a conflict between the permit and the “Maryland Standards and Specifications for Soil Erosion and Sediment Control,” which are incorporated by reference in Maryland regulations.
Instead of including numeric turbidity limits at this time, MDE has committed to initiate a comprehensive review of the State's erosion and sediment control standards in early 2009 and will develop proposed modifications by May 30, 2010. The revised standards will be incorporated by reference into State regulations and serve as the official guide for erosion and sediment control principles, methods, and practices.
After MDE proposed this general permit, the Environmental Protection Agency (EPA) published a proposal that would require a numeric standard at sites over 30 acres in size. This remains a proposal, and significant technical information will be developed in the public comment process that will inform whether and under which circumstances this numeric standard can be implemented. If appropriate, MDE will incorporate aspects of the proposal in revisions to Maryland Standards and Specifications for Soil Erosion and Sediment. If the EPA adopts regulations requiring effluent limitations, MDE will reopen Maryland’s general permit to incorporate the effluent limitation requirements as soon as possible after federal adoption.
MDE has not included this standard at this time, pending comments on EPA’s proposal by interested parties and the effort by EPA to develop a national standard that would need to be included in the joint federal-State general permit. MDE does believe that the use of certain on-site treatment devices to further reduce the amount of sediments being discharged in stormwater can be effective in certain, but not all, parts of the State.
We believe the procedures established by this general permit are appropriate, can be practically implemented, and protect water quality. The permit requires that permittees control discharges as necessary to meet applicable water quality standards, including MD’s water quality standard for turbidity. It requires the permittee to conduct regular inspections weekly and the next day after any rainfall event resulting in runoff and to maintain on site written reports of all inspections. It specifies what constitutes evidence of a discharge of a significant amount of sediment and when that occurs it triggers a sequence of actions that must be taken by the permittee to bring the site into compliance.
This new general permit will do more than ever in Maryland to stop sediment from damaging our waterways and eroding streambanks. As our state continues to grow, it’s important that we enact measures to limit pollution from new construction. Today’s draft permit, along with Montgomery County’s proposed municipal permit and revised stormwater management regulations, clearly demonstrates that the State of Maryland is taking strong, comprehensive steps to address the serious problems caused by polluted stormwater runoff.
The general permit, a fact sheet, and more information are available online at: http://mde.maryland.gov/programs/Permits/WaterPermits/Pages/permits/watermanagementpermits/mdr10.aspx
In addition to today’s permit for construction activities, a tentative permit for Montgomery County’s storm sewer system addresses retrofitting existing development by an additional 20 percent and proposed regulations to implement the Stormwater Management Act of 2007 would require developers to use state-of-the-art Environmental Site Design practices wherever possible to control runoff and pollution from both new development and redevelopment.
MDE also encourages property owners to reduce stormwater runoff and erosion by using permeable paving surfaces; planting trees, shrubs, and groundcover; allowing “buffer strips” near waterways; and limiting the use of chemical fertilizers and pesticides