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09CW0263,.~~_f.. ~; \ j{ r': 7 ' `fit:: `~` ~ ~~ ~~~~ STAFF' S REQUEST ANALYSIS AND RECOMMENDATION 09CW0263 Martin Marietta Materials, Inc Clover Hill Magisterial District West line of Warbro Road April 29, 2009 BS REQUEST: An exception to the requirements of the Chesapeake Bay Preservation Ordinance (CBPO) to allow encroachment into the Resource Protection Area (RPA). RECOMMENDATION Recommend approval with the one condition below for the following reasons: A. A Water Quality Impact Assessment (WQIA) has been approved. B. The six (6) findings, as required by Section 19-235 (b)(1) have been satisfied. C. The proposed development is consistent with the Chesapeake Bay Preservation Ordinance. ~nNnTTTnN~ The mitigation measures outlined in the Major Water Quality Impact Assessment Martin Marietta Midlothian Quarry, dated April 10, 2009, prepared by Townes Site Engineering, shall be incorporated into the site plan review process and implemented. The Department of Environmental Engineering may approve alternative mitigation measures if it is determined that such alternatives will not increase impacts to the RPA or downstream water bodies. (EE) (NOTE: Approval of this exception does not convey any privileges which would limit the imposition of all pertinent ordinances and policy requirements.) Providing a FIRST CHOICE community through excellence in public service GENERAL INFORMATION Location: 3500 & 3600 Warbro Road, which is within the Swift Creek drainage basin. Tax IDs Part of parcel 737-683-2003 and Part of parcel 736-683-3056. Existing Zonin A Size: 270 acres Existing Land Use: The property is industrialized and has been utilized for the mining and processing of native granite for the production of crushed stone since the 1960's. Also located on the property and supported by the quarrying operation are several accessory businesses including an asphalt plant operated by Branscome, Inc. and a concrete batch plant operated by Ready Mixed Concrete Company. Condition of Resource Protection Area: The RPA on the subject site is located adjacent to an unnamed tributary, which flows through the existing operation and eventually empties into Nuttree Branch. The character of the RPA buffer on the property consists of areas containing an undisturbed forested and wetland buffers, areas containing moderate disturbed sparsely vegetative buffers and areas heavily disturbed having little to no vegetative buffer or natural soils. Area of Probosed RPA Encroachment: The area of the encroachment for this proposed development will impact a total of 16.5 acres of RPA, of which 2.0 acres is undisturbed vegetation with the remaining 14.5 acres having been significantly altered by pre-existing uses. PROPOSAL The applicant has requested an exception for potential impacts to lands within designated Chesapeake Bay Preservation Areas (CBPAs) and downstream water bodies. The applicant asserts that implementation of the limits of CBPAs, which include Resource Protection Areas (RPAs) around an onsite perennial channel and wetlands, would render the parcel unusable for further mining activities. The Chesapeake Bay Preservation Ordinance (CBPO) requirements of the Zoning Ordinance specify that a RPA buffer be established adjacent to perennial water bodies, to include connected and contiguous wetlands, and consist of an undisturbed 100 foot natural vegetative area. Amendments to the CBPO in 2004 required site specific field 2 09CW0263-APR29-BOS-RPT assessments to be conducted in order to determine water bodies having perennial flow. Assessments performed on the stream system draining to the subject property resulted in the determination of perennial flow, and therefore the establishment of RPA buffer. As a result, all downstream channels associated with this stream system, to include the ditch bisecting the mine were determined as having RPA buffer requirements. In order to meet the needs of the current and future mining operations, the applicant has requested an encroachment into RPA buffer. Of the 270-acre site, approximately 2.0 acres of forested buffer and 14.5 acres of previously disturbed buffer will be converted into the future quarry pit expansion resulting in excavation of the buffer area and channel system in order to extract the mineral deposits beneath this area. In order to accomplish this, the existing upstream flow will be permanently redirected through an underground pipe system around the eastern side of the mine operation and discharged through an outfall to an existing stream located to the south of the existing quarry. ANALYSIS To approve a Chesapeake Bay Preservation Ordinance (CBPO) exception request, the Board of Supervisors must determine that the proposed development satisfies the six (6) findings, outlined below, as required by Section 19-235 (b)(1) have been satisfied. The applicant addressed these findings as part of the application process. The applicant's position can be found on Attachment A. The first criteria for granting such an exception is: 1. The requested exception is the minimum necessary to afford relief. Much of the RPA buffer on the site has been already compromised as a result of the pre- existing mining operations. The proposed expansion of the existing quarry pit and operations must precede north and westward due to topographic and development constraints. This is necessary in order to accommodate the future mining operations and provide the projected extraction supply. 2. Granting the exception shall not confer any special privileges upon the applicant that are denied by this division to other property owners who are subject to its provisions and who are similarly situated. The existing encroachments as part of the current operation occurred prior to CBPO requirements. This request is a further expansion of this already acceptable operation in order to ensure the anticipated use and value of the property continues to be available. 3. The exception request is in harmony with the purpose and intent of this division and will not result in a substantial detriment to water quality. The proposed expansion of the existing use will allow for the rerouting of the upstream flow around the industrialized operation, therefore reducing potential future water quality impacts and in addition, provide the ability for a greater level of control and treatment of stormwater runoff from current and future operations. It is expected that rerouting up- stream flow around the industrial operations will improve down steam water quality. 3 09CW0263-APR29-BOS-RPT 4. The exception request is not based upon conditions or circumstances that are self- created or self-imposed. Approval of the nature of the operation occurred prior to the adoption of the county's CBPO ordinance and therefore significant portions of the RPA buffer have existing impacts. Additional proposed RPA encroachments are due to the expansion of the already approved use for this type operation. Exceptions may be granted for this type of request provided the development meets certain standards. S. Reasonable and appropriate conditions are imposed, as warranted, that will ensure that the permitted activity will not cause a degradation of water quality. Potential impacts to water quality are mitigated by redirecting up-stream flows around the operation, providing additional on-site stormwater treatment and control, re-vegetation, and development of operational specific water quality education for staff. 6. The request is being made because of the particular physical surroundings, use, shape or topographical conditions of the specific property involved or property adjacent to or within 100 feet of the subject property, or a particular hardship to the owner will occur, as distinguished from a mere inconvenience, if the strict letter of this division is carried out. The request is being made specifically due to the topographical features, development standards and requirements of the site and operational needs of this business which requires the necessity for the expansion and further encroachment within the RPA. The mineral deposits accessible from the current quarry pit area are projected to run out within the next couple of years. Mineral extraction potential for the expanded quarry pit is projected to last for 20-30 more years. Strict application of the RPA requirements would eventually preclude the continued use of the parcel for mining operations. CONCLUSION The applicant has requested an exception for potential impacts to lands within designated Chesapeake Bay Preservation Areas (CBPAs). Implementation of the limits of CBPAs, which include Resource Protection Areas (RDAs), renders the continued mining operation of the parcel unusable. The proposed encroachment into the 100 foot buffer would permit the majority of the impacts within the areas of existing encroachments and allow for the existing use to continue in order to extract the projected amount of existing mineral deposits. As mitigation for the encroachment, summarized in Attachment B, the applicant proposes to relocate the flow from up-stream drainage to an existing vegetative buffer channel located adjacent to the project, provide additional on-site stormwater runoff quality and other mitigation techniques to further enhance stormwater runoff from the existing operation. Staff recommends that the Board of Supervisors approve the applicant's request subject to the one condition included in this report. 4 09CW0263-APR29-BOS-RPT ATTACHMENT - A Applicant's response to the six (6) findings as required by Section 19-235 (b)(1). REQUEST FOR AN EXCEPTION TO THE REQUIREMENTS OF THE ZONING ORDINANCE Martin Marietta Materials, Inc. Midlothian, Virginia Quarry Tax IDs part of parcel 737-683-2003 and part of parcel 736-683-3056 Provide the justification for the proposed exception and a discussion of how each of the following findings is met: 1) The requested exception is the minimum necessary to afford relief. The existing quarry pit must be excavated to the north and west due to topography, required setbacks and property line locations. The area of the lower pond and RPA must be excavated in order for the mine expansion project to meet projected extraction supply. Therefore, the scope of the expansion and the proposed RPA encroachments are the minimum necessary to allow the mine to meet its previously projected and planned lifetime. 2) Granting the exceptions does not confer upon the applicant special privileges that are denied to other property owners who are similarly situated. The Martin Marietta Midlothian Quarry has been in operation since the 1960s under the assumption that the full extraction potential of the mine, within the mine's current boundaries, would be supported by Chesterfield County. Therefore, allowing the proposed RPA encroachment is in no way granting Martin Marietta special privileges that are denied to other similarly situated property owners. In addition, there are no other large industrial mining operations in Chesterfield County that have been continuously in operation since prior to the county's adoption of the Chesapeake Bay Preservation Act that could face similar CBPA issues. 3) The exception is in harmony with the purpose and intent of the Chesapeake Bay Preservation requirements of the Zoning Ordinance and will not result in a substantial detriment to water quality. Although the proposed expansion of the Martin Marietta quarry will result in the encroachment of resource-protection area, the proposed work will actually improve downstream water quality. The rerouting of the upstream flow around the industrialized operation will stop the erosion of sediment from the ditch that bisects the mine property. 5 09CW0263-APR29-BOS-RPT In addition, the expansion of the quarry pit will allow a greater amount of stormwater runoff from the mining operation to flow into the quarry pit and be treated by a large storage area and increased retention time. The construction of the proposed berm and weir upstream of the pit-expansion area will also result in the treatment of stormwater runoff from the entire upstream watershed. In storm events from approximately 5-year and greater intensity, a portion of the stormwater that cannot be conveyed by the proposed culverts will flow over the emergency spillway of the berm and into the quarry pit. This water will then be pumped out of the pit over time into the clarification pond prior to discharge. 4) The exception request is not based on conditions or circumstances that are self- created or self-imposed. The Martin Marietta Quarry has been in operation in its present location since the 1960s. At the time the mine was approved for operation, there were no CBPA requirements on the site. The proposed quarry expansion area has been a component of the mine plan since the initiation of mining activities on the site. Additionally, the resource-protection area currently presumed present on the mine property is a result of information obtained from upstream properties not under the control of Martin Marietta, not from information collected from the Martin Marietta property. Prior to the county's adoption of the current CBPA regulations, the proposed expansion activities would not have affected county resource-protection areas. Therefore, Martin Marietta could have in no way avoided, nor be reasonably asked to avoid, the currently proposed impacts to resource-protection areas. 5) Reasonable and appropriate conditions are imposed, as warranted, that will ensure that the permitted activity will not cause a degradation of water quality. In addition to the improvement in stormwater management and sedimentation potential on the subject site and within the entire upstream drainage area as discussed in finding #3 above, Martin Marietta proposes the following mitigation to compensate for the proposed impacts to resource-protection area: • Revegetation of the mine property outside the quarry pit in accordance with mine reclamation requirements at the closure of the mining operation. • Additional plantings of all current and proposed overburden storage areas in addition to Department of Mineral Mining vegetation requirements; specifically, loblolly pine whips will be planted at 10 feet on center around the perimeter of all existing and proposed overburden storage areas. 6 09CW0263-APR29-BOS-RPT • Literature regarding the importance of water quality and how everyday actions can improve or reduce water quality will be placed in all staff common areas and office locations. • Signs discussing the importance of equipment maintenance and spill cleanup will be posted in visible locations around the site and at the equipment maintenance areas. 6) The request is being made because of the particular physical surroundings, use, shape or topographical conditions of the specific property involved or property adiacent to or within 100 feet of the subiect property, or a particular hardship to the owner will occur, as distinguished from a mere inconvenience, if the strict letter of the CBPA Zoning Ordinance is carried out. The proposed location of the quarry pit expansion area to the north and west of the existing pit is the only possible location for mine expansion. Site topography, pit excavation slope requirements, property limits, adjacent development, required setbacks and the location of the subsurface mineral deposits all limit the possible expansion area of the quarry pit to its currently proposed location. The mineral deposits accessible from the current quarry pit area are projected to run out within the next couple of years. Mineral extraction potential for the expanded quarry pit is projected to last for 20-30 more years. Should the proposed resource-protection area encroachment be denied, Martin Marietta will be forced to close the Midlothian mining operation and focus on the development of anew mine in a new location outside Chesterfield County. 09 CW0263-AP R29-B OS-RPT ATTACHMENT - B The outline below summarizes some of the measures submitted as part of the WQIA for the mitigation of the requested encroachment and water quality improvement. REQUEST FOR AN EXCEPTION TO THE REQUIREMENTS OF THE ZONING ORDINANCE Martin Marietta Materials, Inc. Midlothian, Virginia Quarry Tax IDs part of parcel 737-683-2003 and part of parcel 736-683-3056 The following is a partial list of mitigation measures for the proposed encroachments to the RPA. A more detail discussion of the measures are on file within the document Major Water Quality Impact Assessment Martin Marietta Midlothian Quarry, dated April 10, 2009, prepared by Townes Site Engineering. These measures will provide additional stormwater treatment and water quality benefits/improvements. The remaining environmental features will be protected during construction by maintaining erosion and sediment control standards. After construction the features will be protected by increased buffers and stormwater outlet protection in order to reduce concentrated flows and reduce down stream erosion. 1. Re-routing of the up-stream flow around the working mine site and away from the existing industrial operations. 2. Provide for a greater portion of the site runoff to be diverted to the pit area for increased settling and additional clarification. 3. Provide for up-stream storm flows of 5 year or greater intensity to overflow into the existing pit in order to provide quality and quantity control during storm events. 4. Woody re-vegetation of the areas around the perimeter of the existing and future overburden stockpiles. Additional re-vegetation of mine property upon closure of operation. 5. Provide education and increase awareness of water quality concerns to its site employees. 6. Educational signs and literature detailing operational specific water quality concerns. 7. Provide for protection for the remaining RPA area outside of the proposed expansion area. This area is approximately 2.2 acres in size and is located in the northeast corner of the subject parcel. 8 09CW0263-APR29-BOS-RPT Martin Marietta Aggregates Midlothian Quarry Summary of Facts for an Exception from the Chesapeake Bay Preservation Ordinance In order to continue operations at its existing mine in Chesterfield County, Martin Marietta is applying for an exception to the Resource Protection Area (RPA) regulations of the County's Chesapeake Bay Preservation Ordinance (CBPO). The subject area is in the northern part of Martin Marietta's Midlothian Quarry along Warbro Road just north of Hull Street Road. This summary serves to highlight the key issues related to the requested exception. More detail is available in the Water Quality Impact Assessment and Planning Department staff report. Key Points of Proposed Activity • Expansion is necessary to extend the life of Midlothian Quarry. • Water flow must be rerouted and piped to allow for the expansion. • The reroute will affect an open water pond and surrounding RPA, as well as an open ditch which flows through the highly disturbed quarry site. • Both features were formed and modified through the years of mining operations at the site. • Rerouting water flow will improve overall water quality and permit Martin Marietta to expand mine operations. • The Virginia Department of Environmental Quality and the U.S. Army Corps of Engineers have permitted the reroute water flow and impact the water features. Vesting In a letter dated March 31, 2009, the Director of Planning-with concurrence from the County Attorney-made a determination regarding Martin Marietta's vested rights. The Director concluded that Martin Marietta has rights to develop within the current ditch area and reroute the ditch, pursuant to the requirements prior to the 2004 CBPO amendments. The County's vesting determination, however, is constrained by the Final Order in the case County of Chesterfield, Virginia v. Chesapeake Bay Local Assistance Board, Case No. CL07-2743, September 30, 2008, which requires that a 25 foot buffer remain for RPAs, despite a determination of vested rights. Required Findings Pursuant to Section 19-235(b)(1), an exception from the CBPO requires certain findings for justification. Those findings are: Minimum exception necessary to afford relief Given topographical and site constraints, and in order to reroute water flow around the mine expansion, water flow must be routed as proposed. 2. No special privileges Existing encroachments are part of the ongoing mining operation permitted prior to CBPO requirements. The request is to expand already acceptable operations and meets the standards set forth in Section 19-235(b). 3. In harmony with the purpose and intent of the CBPO Under existing conditions water flows through the highly disturbed mining operations area. Rerouting water flow around the mine area will stop mine runoff from draining directly into the tributary, reduce erosion and sedimentation potential, and improve overall water quality. 4. Circumstance is not self-created or self-imposed Topography and site conditions demand that water flow be diverted as proposed. Ongoing mining operations were permitted prior to CBPO adoption. RPA buffers have existing impacts, and proposed encroachments are due to expansion of the already approved use. 5. Reasonable conditions to protect water quality The proposed encroachment will reduce sedimentation potential and improve water quality by rerouting water flow around the denuded, erodible mine area. Standard erosion controls will minimize potential erosion and sedimentation during construction. Best Management Practices, as regulated by the Department of Mines, Minerals and Energy, are part of ongoing mining practices. Martin Marietta proposes to provide literature and signage approved by the County Office of Water Quality to increase awareness of water quality concerns among onsite employees. 6. Particular physical surroundings use shape or topographical conditions This development faces unique challenges not routinely encountered by other developments. Expansion of quarry operations is impossible without impacting the water features and buffer areas. Based upon past affirmative governmental acts, Martin Marietta has invested substantially in the expansion of mining operations and has received a vesting determination covering a large portion of the area. Strict application of the Ordinance would mean the Martin Marietta Quarry would be shut down in the near term despite Martin Marietta's long term investments and operations at the quarry. `~~830645 I Martin Marietta Aggregates Exception to CBPO ' ®~l~ ~~ ~ ~ ~~~ ~ R ~~~ a o ~ g~ d t9gi~k S ~ 1 .-~ \ ~e ~ ~ ,~~ ~ I _ r,l ) - _. 1 \ ~~ m A / ~ ~ I \_,~_~ d ,- '_ ~ r ~~ ~~ s n - ~ Ra ~ ~ va ,+ r \\ o \\ ~p E ~ I i ~ I i i j ~ MARTIN MARIETTA MIDLOTHIAN QUARRY ~ CHESTERFIELD COUNTY, VIRGINIA ~ I ~ ~ iYQIA PLAN - FIGURE 2 ao 1 ~~~_°°__. o°~o° - Townes SITE ENGINEERING \. 8860 Lori Road, 3ulte 201 Chesterfield, Virginia 29892 ASK US HOW Phone:(9041'748-9011 Faz: (804) 748-2590 ~~mmeellll towneeOcctownee,com ~~~ ~ ~~~~e