Water Quality Best Management Practices for the Aggregate Mining Industry

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Water Quality Best Management Practices for the Aggregate Mining Industry WATER QUALITY BEST MANAGEMENT PRACTICES FOR THE AGGREGATE MINING INDUSTRY Prepared For: Georgia Construction Aggregate Association 9810-A Medlock Bridge Road Suite 202 Duluth, Georgia 30097 Prepared By: Highland Engineering, Inc. 1455 Lincoln Parkway, Suite 200 Atlanta, Georgia 30346 May 21, 2009 DISCLAIMER THIS MANUAL IS INTENDED TO BE USED AS A GENERAL GUIDE TO ASSIST THE REGULATED COMMUNITY IN DESIGNING AND IMPLEMENTING EFFECTIVE WATER QUALITY “BEST MANAGEMENT PRACTICES” IN CONJUNCTION WITH AGGREGATE MINING OPERATIONS. IT IS NOT INTENDED TO BE A SOLE SOURCE FOR SUCH INFORMATION, NOR IS IT INTENDED TO PROVIDE LEGAL ADVICE OF ANY NATURE. USERS OF THIS MANUAL ARE EXPRESSLY CAUTIONED NOT TO RELY SOLELY ON THIS MANUAL FOR “BEST MANAGEMENT PRACTICES” INFORMATION, AND ARE ENCOURAGED TO SEEK LEGAL, TECHNICAL AND ENGINEERING ADVICE FROM QUALIFIED PROFESSIONALS WHO ARE FAMILIAR WITH THE RELEVANT SITE AND PROJECT. THE ORGANIZATIONS AND INDIVIDUALS CONTRIBUTING TO THE PREPARATION OF THIS MANUAL EXPRESSLY DISCLAIM ANY RESPONSIBILITY OR LIABILITY FOR ANY ACTS OR OMISSIONS TAKEN BY ANY PARTY AS A RESULT OF THE USE OF THIS MANUAL. TABLE OF CONTENTS Page 1.0 INTRODUCTION …………………………………………………………… 1 2.0 ACKNOWLEDGEMENTS …………………………………………………. 3 3.0 REGULATORY DISCUSSION …………………………………………….. 4 3.1 Georgia Department of Natural Resources, Environmental Protection Division - Land Protection Branch - Surface Mining Unit ……………. 4 3.2 Georgia Department of Natural Resources, Environmental Protection Division - Watershed Protection Branch ……………………………….. 5 3.3 United States Army Corps of Engineers (USACE) …………………….. 10 3.4 Local Jurisdiction ………………………………………………………... 10 4.0 MINE LIFE CYCLE AND CORRESPONDING BMPS …………………. 11 4.1 Planning and Permitting ………………………………………………… 11 4.2 Site Development ………………………………………………………… 14 4.3 Active Site Management …………………………………………………. 32 4.4 Operations ………………………………………………………………… 43 4.5 Reclamation ………………………………………………………………. 52 APPENDICES A. Erosion and Sediment Control Inspection Checklist B. Regulatory Contacts C. Glossary of Erosion and Sediment Control Terms D. References 1.0 INTRODUCTION The objective of this manual is to provide the aggregate mining industry with a summary of some of the regulatory requirements, which may be applicable to their operations. In addition this manual provides a description of the practical application of best management practices (BMPs) for improved water quality from both point source and non-point source waters potentially generated on aggregate mining facilities. This manual is prepared as a general guide to water quality management and should not be relied upon as a complete source of all applicable regulatory requirements. The principal pollutant in both point source and non-point source waters generated on aggregate mining facilities is total suspended solids (TSS). Depending upon the formation being mined and the nature of overburden material, pH may also be a water quality concern for waters discharged from aggregate mining sites. While pH may be a concern on some sites, this manual will generally focus on the control of the more prevalent water quality issue of TSS. The regulatory community has addressed TSS loads and pH on receiving streams from point sources since the enactment of the Clean Water Act (CWA) in 1972. Limitations on the concentration of TSS in process water point discharges are identified and enforced under the National Pollutant Discharge Elimination System (NPDES) permit program. Recently the regulatory community has focused efforts on non-point sources of pollutants, including TSS. These efforts, which are directed at certain industrial classifications, are also enforced by NPDES permit. This permit, the NPDES Storm Water Permit associated with Industrial Activity, is applicable to certain facilities in the aggregate mining industry. In conjunction, these two types of NPDES permits provide regulatory control over potential sources of sediment from process point source discharges and from storm water contacting industrial operations on aggregate mining facilities. While occasionally faced with periods of drought, Georgia is generally fortunate to have abundant surface water resources with over 40,000 miles of perennial streams and 23,000 miles of intermittent streams. In addition the state has over 425,000 acres of lakes and reservoirs and 4.8 million acres of wetlands. The surface waters provide the majority of drinking water supplies for the state and offer significant aesthetic and recreational benefits. Excessive sediment loads cause changes to stream channel morphology resulting in changes to depth, width and flow velocity. Excessive sediment has a negative impact biologically as well. It can be abrasive to fish gills, scour benthic organisms, and dislodge stream vegetation. Excessive sediment loads can also result in increased water temperatures and can play a significant role in the transport and fate of other pollutants. While extreme pH conditions can have direct effect on the biological constituents of receiving waters, the role of pH in determining the solubility and biological availability of chemical constituents such as nutrients (e.g., phosphorus, nitrogen, and carbon) and contaminants (e.g. heavy metals) is perhaps a greater concern. The Georgia Environmental Protection Division (GAEPD) has permitted 80 operating quarries in Georgia. The average land area of these facilities is approximately 360 acres (total) 360K which includes pits, aggregate processing plant, rail and undisturbed buffers. 1 Erosion and sediment control is a major focus of all mine operators during all phases of the quarry operating life. In compliance with the provisions of the Georgia Water Quality Control Act (CWA) and the rules and Regulations promulgated to each of the Acts, new and existing storm water point sources within the State of Georgia are required to have a permit to discharge storm water associated with industrial activity to the waters of the State of Georgia. Through proper planning and implementation of erosion and sediment control measures, the aggregate mining operations effectively manage the quality of water discharged from its operations. This manual discusses specific BMPs to control the quality of water discharged from aggregate mining facilities. Information is presented in two parts, beginning with a discussion of environmental regulations affecting water quality from the aggregate mining industry. The remainder of the manual addresses the planning and implementation of BMPs through each of the stages of an aggregate mining operations including planning and permitting, construction, operation and reclamation. 2 2.0 ACKNOWLEDGEMENTS This manual was prepared to establish the best current practices for the protection of our environmental resources while still providing a needed natural construction product for the economic viability of our communities. The construction and aggregate industry is composed of a combination of open pit quarry operations, sand and gravel facilities, borrow pits and underground operations. The materials in this document are primarily applicable to open pit quarry operations. In Georgia, over 90% of construction aggregate is produced in open pit quarry operations. These operations produce approximately 90 million tons per year of product. These products are used in three principal markets; highway construction, residential home construction and commercial construction. The use is equally divided between these three categories. In essence, construction aggregates are the essential building blocks for our infrastructure. Our motto is that construction aggregates are the “Foundation for a Quality Life.” We are thankful for several individuals who have been responsible for the creation of this document. The document was developed by Highland Engineering under contract to the Georgia Construction Aggregate Association (GCAA). The Work was managed by the Environmental Committee of the GCAA. Committee members collaborating on this document include Jim Zadorozny (Hanson Aggregates), Joyceann Lee (Lafarge Aggregates), Dean Pease (Agg. USA), Nils Thompson (Leaggette, Brashears & Graham), and Gary Canter (Vulcan Materials). Thanks go to Randy Quintrell, GCAA Legal Counsel, for his review and editorial content. In addition, the authors and committee thank John Cardosa and the GCAA staff for maintaining regulatory liaison and providing the structure and schedule for the preparation of this document There are many sources for the materials in this document. A list of these sources is found in the appendices. A list of contributors is also found in the appendices. This is not an engineering manual. It is intended to provide guidance for best practices in our industry. 3 3.0 REGULATORY DISCUSSION The aggregate mining industry is regulated by a number of government agencies. Following is a discussion of the agencies responsible for water quality at aggregate mining facilities and the principal regulations applicable to aggregate mining operations. 3.1 Georgia Department of Natural Resources, Environmental Protection Division (GAEPD)- Land Protection Branch - Surface Mining Unit Agency Description The lead agency for the aggregate mining industry in Georgia is the Land Protection Branch - Surface Mine Unit of the Georgia Environmental Protection Division. This agency is responsible for reviewing, approving and permitting surface mining activity. The Surface Mining Unit also is the principal enforcement agency for aggregate mining operations.
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