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HomeMy WebLinkAboutNC0002468_SARP_Rev0_Appx F_20161201December 2016Amec Foster Wheeler Environment & Infrastructure, Inc. Duke Energy Coal Combustion Residuals Management Program Dan River Steam Station Site Analysis and Removal Plan Revision 0 APPENDIX F: CONSTRUCTION QUALITY ASSURANCE PLAN - DAN RIVER DECOMMISSIONING PLAN CONSTRUCTION QUALITY ASSURANCE PLAN DAN RIVER STEAM STATION REVISION 0 Prepared for Duke Energy 400 South Tryon Street Charlotte, North Carolina 28202 December 2016 Prepared by Amec Foster Wheeler Environment & Infrastructure, Inc. Project 7810140065.09 Amec Foster Wheeler Environment & Infrastructure, Inc. December 2016 Construction Quality Assurance Plan Dan River Steam Station Site Analysis and Removal Plan Revision 0 i TABLE OF CONTENTS 1. INTRODUCTION .............................................................................................................1 2. BACKGROUND ..............................................................................................................1 3. PROJECT TEAM AND RESPONSIBILITIES ....... ERROR! BOOKMARK NOT DEFINED. 3.1. Owner .................................................................................................................................. 2 3.2. Design Engineer of Record (Engineer) ............................................................................... 2 3.3. Construction Quality Assurance Engineer .......................................................................... 2 3.4. Engineering Technicians ..................................................................................................... 3 3.5. Prime Contractor ................................................................................................................. 3 3.6. Regulatory Agency .............................................................................................................. 3 4. DOCUMENTATION .........................................................................................................3 4.1. Record Documentation ....................................................................................................... 4 4.2. Error! Bookmark not defined. 4.3. Design, Specification, and Drawing Changes ..................................................................... 4 4.4. Non-Conformances ............................................................................................................. 4 4.5. Record Drawings ................................................................................................................. 4 4.6. Certification Report ............................................................................................................. 5 5. QUALITY ASSURANCE PROGRAM ..............................................................................5 5.1. Fill Density Testing .............................................................................................................. 5 5.2. Instrumentation ................................................................................................................... 6 5.3. Verification of Ash Removal ................................................................................................ 7 5.4. Surveying ............................................................................................................................ 7 Figures Figure 1 – Site Vicinity Map Figure 2 – Instrumentation Locations Tables Table 1 – Instrumentation Table 2 – Testing Frequency Amec Foster Wheeler Environment & Infrastructure, Inc. December 2016 Construction Quality Assurance Plan Dan River Steam Station Site Analysis and Removal Plan Revision 0 1 1. INTRODUCTION This document presents the Construction Quality Assurance Plan (CQA) Plan for the Dan River Steam Station Dam Decommissioning project in Rockingham County, North Carolina. The purpose of the CQA Plan is to identify the quality assurance procedures, standards, and methods that will be employed during the project to provide assurance that the requirements of the drawings, specifications, regulatory permits, and owner specified health, safety and environmental requirements are met. The CQA Plan is specific to the referenced project and is prepared in compliance with the North Carolina Coal Ash Management Act of 2014. The primary objective of the scope of work for the Dam Decommissioning project at Dan River Steam Station (hereafter referred to as Dan River) includes excavation and removal of CCR materials currently stored in the areas known as the Primary Ash Basin (RO CKI-237), Secondary Ash Basin (ROCKI-238), Ash Fills 1 and 2, and ancillary areas. The scope of work includes all ancillary activities such as erection and maintenance of erosion and sediment control, dewatering, CCR removal, grading to design grades, permanent stabilization, and all other activities required to achieve the primary objective. The scope of work also includes obtaining and complying with regulatory permits required for performing the work. The project will be performed with regard to safety and environmental standards in compliance with local, state, and federal regulations as included in the site specific environmental, health and safety program. 2. BACKGROUND The Dan River Steam Station is located on the Dan River near Eden in Rockingham County, North Carolina. Historically, the primary ash management facilities included the Primary and Secondary Ash Basins which have served as the main ash storage component for plant operations. The site has two regulated impoundment structures, the Primary Ash Basin Dam (State ID ROCKI-237) and the Secondary Ash Basin Dam (ROCKI-238). Two additional ash storage areas at the station include Ash Fills 1 and 2. Ancillary ash areas include an area between Ash Fills 1 and 2 commonly called the dredge area. Power production at the plant was discontinued in 2012. The closure of the ash management facilities at the station is a part of the overall station decommissioning plan. The CCR materials in the storage areas at Dan River will be excavated and removed using conventional excavation equipment. A portion of the CCR material will be transported and placed in the Maplewood Landfill in Amelia County, Jetersville, Virginia. The remaining CCR material will be placed in a new on-site lined landfill. Construction of the on-site landfill is anticipated to begin in 2016. Upon establishing final grades, the site will be seeded to establish grassy ground cover per approved grading plan drawings and specifications. Final grades have been designed such that the footprint of the currently jurisdictional dams no longer impound water, allowing the dams to be removed from the state dam inventory and jurisdiction of state dam safety regulations. In addition to establishing vegetative ground cover, relatively gentle slopes will be established Amec Foster Wheeler Environment & Infrastructure, Inc. December 2016 Construction Quality Assurance Plan Dan River Steam Station Site Analysis and Removal Plan Revision 0 2 during final grading to control runoff velocities. Following completion of the ash removal, the short term disposition of the site will be grading the site to drain, establishing the vegetative cover and maintaining the site in an undeveloped state. 3. PROJECT TEAM AND RESPONSIBILITIES The following identifies the roles and responsibilities for the primary parties associated with the project, including the anticipated duties and expectations each party will fulfill in execution of the work associated with implementation of the project. 3.1. Owner The Owner of the site and project is Duke Energy Carolinas, LLC (Duke). The Owner is ultimately responsible for oversight and authorization of the work and assuring that the work is performed in general accordance with the specifications, drawings, permits, this CQA Plan, and other contractual documents. The Owner has the right to delegate its oversight authority to third parties contracted with the Owner but will maintain ultimate responsibility for the successful implementation of the project. The Owner will maintain the authority to make final decisions regarding all aspects of the project in compliance with local, state, and federal regulations. For this project, the Owner will have sole authority to suspend or stop work if, in their opinion, the work is being performed in an unsafe manner, the work is not meeting quality standards, or changes to the scope of work must be enacted to comply with the spirit of the objectives of the project. 3.2. Design Engineer of Record (Engineer) The Design Engineer of Record (Engineer) is the Engineer of Record for the Project Drawings and Specifications. The Engineer is delegated limited and selected authority at the discretion of the Owner. The Engineer acts in a consultant role to the Owner on aspects of the project for which the Owner seeks direction in the decision making process. The Engineer has no authority to stop or suspend work at the site, only the authority to recommend remedial actions for the Owner’s consideration. 3.3. Construction Quality Assurance Engineer The Construction Quality Assurance Engineer (CQA Engineer) will be experienced in quality assurance testing and monitoring. The CQA Engineer will report to the Owner and can be employed by the same entity as the Design Engineer of Record. The CQA Engineer may be a Duke employee. The CQA Engineer serves as the on-site representative of the Owner and is responsible for the field implementation of the approved quality assurance program as follows:  Monitor the quality assurance activities of the field testing and document conformance with test procedures and the Technical Specifications  Inform the Engineer of quality assurance activities and non-conformance to the approved CQA program, if any Amec Foster Wheeler Environment & Infrastructure, Inc. December 2016 Construction Quality Assurance Plan Dan River Steam Station Site Analysis and Removal Plan Revision 0 3  Observe that sample handling procedures are in accordance with the appropriate guidelines for the testing to be conducted  Organize, assign, and direct engineering technicians  Maintain an awareness of the overall field testing operations to identify conditions that may jeopardize the quality of testing 3.4. Engineering Technicians The engineering technicians (technicians) are responsible for field observations and testing at the direction of the CQA Engineer. Technicians will be assigned to the project as deemed necessary by the CQA Engineer. The CQA Engineer may perform and conduct field observations and testing himself. Technicians will be under the direct supervision of the CQA Engineer. 3.5. Prime Contractor The Prime Contractor will be responsible for performing and managing construction activities required for completing the project. The Prime Contractor is responsible for performing the work in compliance with the requirements and to the quality standards of the specifications, drawings, permits, and this CQA Plan. The Prime Contractor is responsible for overseeing and managing their personnel, including the personnel of their Subcontractors such that the work is performed safely and effectively and in compliance with local, state, and federal safety and environmental regulations to include the Owner’s site specific environmental, health, and safety rules. 3.6. Regulatory Agency The Regulatory Agency having direct regulatory authority of the project is the North Carolina Department of Environmental Quality, (NCDEQ). With respect to dam decommissioning the lead agency is the NCDEQ, Division of Energy, Mineral, and Land Resources, Land Quality Section, Dams Program. The Regulatory Agency has the authority to inspect the project at any time during the course of the work, and has the authority to direct the Owner to suspend or stop the work with appropriate cause. Upon direction to suspend or stop the work, the Regulatory Agency should provide remedial measures to the Owner, that once implemented, should allow for work to continue. 4. DOCUMENTATION This section provides a description of project documentation and record keeping that will be maintained during the course of the work as the project record. Amec Foster Wheeler Environment & Infrastructure, Inc. December 2016 Construction Quality Assurance Plan Dan River Steam Station Site Analysis and Removal Plan Revision 0 4 4.1. Record Documentation Reports will be completed by designated Owner personnel to serve as a record of the project. The reports are intended to summarize work activities, serve as a record of important discussions and/or decisions, action items, or other information that the Owner deems important or critical to the project record. The Owner, at their discretion, may require other entities, such as the CQA Engineer, to maintain records as well. The CQA Engineer and technicians will be responsible for documenting construction, monitoring, and testing activities by taking photographs. Photographs should be organized and documented in photo-logs and/or by including them in reports, monitoring logs, and test data sheets. Photo-logs should include a unique identifying number corresponding to the photograph file name, the date and location where the photograph was taken, and a description of the photograph subject matter. 4.2. Design, Specification, and Drawing Changes Design, specification and drawing changes may be required during construction. Proposed changes may be initiated by the Design Engineer of Record, Contractor, CQA Engineer, or Owner and submitted to the Design Engineer of Record for consideration. Design, specification and drawing changes may be made only with the approval of the Design Engineer of Record with consent from Owner. Changes that effect the design intent will require approval of that agency. 4.3. Non-Conformances Non-conformance reports are intended to serve as a record of nonconforming items during the course of the work and as a record of the disposition of the non-conformance. Generally, the Owner will initiate the non-conformance procedure based on the recommendation or findings of a third party such as a CQA Engineer. The non-conformance will be evaluated and resolved with the disposition recorded in the non-conformance report. Sample dispositions may include rework of the nonconforming item, replacement of the nonconforming item, or accepting the nonconforming item as installed based on engineering judgment. A record of all non- conformance reports will be maintained at the site during the course of the work at all times for review by requesting representatives of the Regulatory Agency.  4.4. Record Drawings The Contractor shall retain a third-party surveyor registered in the state that the work is performed. The Contractor shall be responsible for submitting to the Engineer the following:  Existing conditions survey (pre-construction, which may be a recent aerial survey not specifically performed for this project)  Existing stormwater piping elevations and locations (including piping to be removed) Amec Foster Wheeler Environment & Infrastructure, Inc. December 2016 Construction Quality Assurance Plan Dan River Steam Station Site Analysis and Removal Plan Revision 0 5  Bottom of excavation grades Installed stormwater piping elevations and locations  Final conditions survey (which may be an aerial survey) The excavation grades survey and any other ground surveys shall be performed on a 100-foot grid with berms, toes, crests and breaks-in-slope also surveyed. Topographic ground surveys shall be performed on the same grid such that survey point locations are consistent with the survey points of the underlying layer. Surveys shall also show contours of the completed surface at two-foot contour intervals. As-built locations and details for existing and installed stormwater piping shall also be submitted to the Engineer by the Contractor. Drawings shall include pipe locations at a spacing that is adequate to identify the position of the pipe. Survey timing should be coordinated so as not to impact the construction schedule of the geosynthetics and overlying materials. 4.5. Certification Report The Engineer will prepare a certification report upon completion of dam decommissioning activities. The certification report will include as-built and record documents that are intended to serve as documentation of the project. For this project, the primary purpose of the record drawings is to capture final grades at the site for use in future projects. A secondary purpose is to fulfill regulatory requirements for developing as-built drawings for decommissioned ash basins. The as-built and record documents will generally include:  Record drawings detailing final grades  Record of quality assurance/control testing including compacted fill, stormwater piping information, instrumentation monitoring, and verification of CCR removal  Record of non-conformance reports  Other relevant information or data at the discretion of the Owner 5. QUALITY ASSURANCE PROGRAM The intent of the Quality Assurance Program is to provide observations, test data, and other recorded information at a sufficient frequency to assure that the work is completed in general accordance with the requirements of the specifications, drawings, regulatory permits, and other controlling documents. A list of the observations and testing requirements for the Quality Assurance Program is included in Table 2. 5.1. Fill Density Testing Final grades at the site will be established by placing and compacting soil materials excavated from onsite sources. The requirements for fill placement are provided in the Technical Specifications. The general requirements for fill density testing include establishing moisture- density relationships for fill materials, visually observing placement of fill materials during construction, performing fill density tests to assess the level of compaction achieved, and Amec Foster Wheeler Environment & Infrastructure, Inc. December 2016 Construction Quality Assurance Plan Dan River Steam Station Site Analysis and Removal Plan Revision 0 6 recording the results of testing for project records. A specific list of the observations and testing requirements for the Quality Assurance Program associated with fill placement is included in Table 2. 5.2. Instrumentation During dewatering of the ash basins, limitations on the drawdown rate within the basins will be imposed to reduce the potential for detrimental conditions developing within the existing dams. The primary concern with regard to the drawdown rate is lowering the water level within the basin significantly faster than the embankment fill materials are able to drain, potentially reducing the overall stability of the impoundment structures. In order to evaluate the initial drawdown limitations, existing instrumentation in the embankments will be monitored to track the drawdown occurring within the embankments compared to the changing water level within the basin. The locations of the instruments to be monitored during the project are shown on Figure 2. The frequency of readings to be performed as a part of the Quality Assurance Program is included on Tables 1 and 2. The water level readings will be tracked in spreadsheet format and plotted versus the dam profile such that the data can be evaluated by qualified personnel. In general, monthly readings of the instrumentation listed in Tables 1 and 2 will be performed during the course of the work until the identified wells are dry or dewatering of the basins is complete. A dry well will be defined as a well that returns a “dry” reading for three consecutive readings. The frequency of reading a well that has been deemed dry may be reduced to either monthly or discontinued subject to any changing condition or data from other wells that suggest reading the dry wells should be reinstated. More frequent readings of the piezometers may be deemed necessary during the course of the project and will be implemented based on the discretion of the qualified person reviewing the data. Amec Foster Wheeler Environment & Infrastructure, Inc. December 2016 Construction Quality Assurance Plan Dan River Steam Station Site Analysis and Removal Plan Revision 0 7 Table 1. Instrumentation Structure Piezometer Screen Interval (ft bls) Sreen Elevation (ft, amsl) Monitoring Frequency P-3 INA INA P-4 INA INA P-5 INA INA P-6 INA INA P-7 INA INA P-11 INA INA OW-10 25-45 514.6-494.6 OW-11 25-45 514.4-494.4 OW-12 25-45 514.5-494.5 OW-13 5-20 491.3-476.3 P-1 INA INA P-2 INA INA OW-7 15-35 514.0-494.0 OW-8 15-35 514.6-494.6 OW-9 15-35 514.5-494.5 Monthly Monthly Primary Ash Basin Dam (ROCKI-237) Secondary Ash Basin Dam (ROCKI-238) 5.3. Verification of Ash Removal Verification and documentation that CCRs have been removed will be required during ash basin closure implementation. In order to meet the basin closure performance standard, Duke’s CCR Removal Verification Procedure will be used to verify that primary source ash has been removed from the basin. Subsequent to removal of the ash pursuant to the CCR Removal Verification Procedure, Duke Energy will implement its Excavation Soil Sampling Plan, which was developed for the purpose of closing the Ash Basins in a manner that meets the closure performance standards set out in Part II, Section 3.(c) of the Coal Ash Act and 40 C.F.R. § 257.102(c). The Excavation Soil Sampling Plan is attached to the Dan River Steam Station Coal Ash Excavation Plan (2016 Update). 5.4. Surveying The Owner may, at their discretion, contract with a CQA Engineer to perform surveying services for the project to validate or verify the surveys performed by others. A specific scope of work and frequency or quantity of measurements for the CQA Engineer performing the surveying services for the Owner will be developed if and when such services are contracted. The scope of work for surveying to be performed by the Prime Contractor is contained in the Technical Specifications. Amec Foster Wheeler Environment & Infrastructure, Inc. December 2016 Construction Quality Assurance Plan Dan River Steam Station Site Analysis and Removal Plan Revision 0 FIGURES As h l e y Ramp Ch u r c h Ram p Ramp Br i d g e Ra m p W a l t e r C h a m b e r s Ashley Fish e r Hill Jo h n Early Ce d a r M e e k s Nc Hig h w a y 1 3 5 Ax t o n Mor g a n F o r d UV1700 UV700 UV1709 UV1700 UV2145 UV770 UV2203 UV65 UV1785 UV2066 UV1962 UV1733 UV770 UV1714 UV1716 UV2203 UV2203 UV2039 UV1747 UV14 UV87 PREPARED BY JMS DATE 11/11/15 CHECKED BY KD DATE 11/11/15 JOB NUMBER FIGURE 17810-14-0065 SITE VICINITY MAP DUKE ENERGY DAN RIVER STEAM STATION ROCKINGHAM COUNTY, NORTH CAROLINA ¯^_ NORTH CAROLINA Project Location 0 6,000 12,000Feet Service Layer Credits: Sources: Esri, HERE, DeLorme, Intermpa, increment P Corp., GEBCO, USGS, FAO, NPS, NRCAN, GeoBase, IGN, Kadaster NL, Ordnance Survey, Esri Japan, METI, Esri China (Hong Kong), swisstopo, MapmyIndia, OpenStreetMap contributors, and the GIS User community Copyright: 2013 National Geogrpahic Society, i-cubed Primary Ash Basin Secondary Ash Basin Ash Fill 1 Ash Fill 2 "J "J "J"J "J "J"J "J !U !U !U !U !U !U !U DAN RIVER FACILITY Primary Pond Secondary Pond Ash Fill 1 Ash Fill 2 P1 P2 P3 P4 P5 P6 P7 P11 ROCKI-237-OW11 ROCKI-237-OW10 ROCKI-238-OW09 ROCKI-238-OW08 ROCKI-238-OW07 ROCKI-237-OW12 ROCKI-237-OW13 PREPARED BY DATE CHECKED BY DATE JOB NUMBER FIGURE 0 130 260 Feet 2 INSTRUMENTATION LOCATIONS CQA PLAN FOR DAM DECOMMISSIONING DAN RIVER STEAM STATION NORTH CAROLINA¯ CHR KRD11/16/15 11/16/15 SOURCE: AERIAL PHOTOGRAPHY FLOWN MAY 5, 2014; TOPOGRAPHIC MAPPING FROM AERIAL PHOTOGRAPHY DATED FEBRUARY 7, 2014; AS-BUILT PIEZOMETER LOCATIONS OBTAINED BY LDSI FIELD SURVEY, 10/30/14 AND 11/14/14. 7810-14-0065 INSTRUMENTATION "J EXISTING DUKE PIEZOMETER (P) !U EXISTING DUKE OBSERVATION WELL (OW) TOPOGRAPHIC CONTOURS - 5 FT (2/7/14) TOPOGRAPHIC CONTOURS - 1 FT (2/7/14) Amec Foster Wheeler Environment & Infrastructure, Inc. December 2016 Construction Quality Assurance Plan Dan River Steam Station Site Analysis and Removal Plan Revision 0 TABLES Amec Foster Wheeler Environment & Infrastructure, Inc. December 2016 Construction Quality Assurance Plan Dan River Steam Station Site Analysis and Removal Plan Revision 0 Table 2. Testing Frequency Component Test Method Frequency Fill Placement/Compaction Visual ● Daily Soil Classification of Fill ASTM D 2488 ● Daily Moisture Density Relationship ASTM D 698 ● 3 proctors prior to commencement of fill placement ● one per 20,000 cubic yards of fill placed or change of material classification In-Place Density Testing ASTM D 2937 ASTM D 6938 ASTM D 1556 ● one per 8,000 cubic yards placed ● minimum of once daily Index Testing ASTM D 6913 or D 422 ASTM D 4318 ● one each per 8,000 cubic yards placed Moisture Content ASTM D 2216 ASTM D 4643 ASTM D 4959 ● one per 8,000 cubic yards placed (in conjunction with field density test) ● minimum once daily or as needed to monitor fill placement Component Test Method Frequency Aggregate Visual ● Per delivery Aggregate Quarry Certification ● Once at beginning of project and at Owner's request thereafter Rip Rap Visual ● Per delivery Rip Rap Quarry Certification ● Once at beginning of project and at Owner's request thereafter Component Test Method Frequency Contractor - Project Controls N/A ● Initial site layout ● At Contractor's discretion thereafter Owner - Record Survey N/A ● Per Owner's scope of work CQA Engineer N/A ● Per Owner's scope of work Component Test Method Frequency Primary Ash Basin (ROCKI-237) P-3, P-4, P-5, P-6, P-7, P-11, OW-10, OW- 11, OW-12, and OW-13 Water level meter Tracking spreadsheet ● Monthly or until "dry" Secondary Ash Basin (ROCKI-238) P-1, P-2, OW-7, OW-8, and OW-9 Water level meter Tracking spreadsheet ● Monthly or until "dry" Component Test Method Frequency Formal Inspection Visual Inspection Form ● Weekly and within 24 hours after each 0.5-inch of rainfall Rain Gauge Visual ● Daily Informal Inspection Visual ● Daily Field Density Testing Earthwork Surveying Instrumentation Erosion and Sediment Control