Investigation and Design
Developed subsurface investigation program in support of the design for a relocated slurry wall, managed implementation of the geotechnical field and laboratory portions of the PDI work plan, reviewed/prepared boring logs and PDI report, and managed the geotechnical laboratory and slurry mixture bench-scale laboratory testing program. Prepared design basis and criteria and evaluated impacts of proposed development on integrity of existing CB wall and proposed replacement SB wall with the evaluation consisting of assessing stability of existing CB wall subjected to proposed roadway embankment loading, stability of proposed bentonite slurry supported trench during construction, stability of proposed SB slurry trench subjected to proposed roadway embankment loading, axial compression and settlement induced strain of existing CB slurry wall due to proposed roadway embankment, and evaluation of strain-induced microcracking and potential decrease in the CB walls hydraulic containment function.
Investigation, Design, Oversight, & Certification
Responsible for development and implementation of a pre-design investigation consisting of a geotechnical investigation, geotechnical laboratory testing, and topographic and physical features surveys. Prepared draft final and final Remedial Action Design deliverables for soil media including a basis of design, design analysis report, calculations, construction drawings, specifications, and quality control plan. Assisted with preparation of permits including Certification of the Soil Erosion and Sediment Control Plan including a Stormwater Pollution Prevention Plan (SPPP) and a NJDEP Division of Land Use Regulation combined permit application which consisted of a Flood Hazard Area Individual Permit, Waterfront Development Permit, and Freshwater Wetland Permit.[permits 6/19 – 10/7/20] KEY prepared a Treatment Works Approval permit application including a NJPDES Discharge to Surface Water (DSW) Category B4B (General Groundwater Petroleum Product Cleanup) application. The temporary treatment system was utilized to treat water generated via dewatering of the RCRA unit during closure activities. The treatment system will consist of gravity settling/equalization, bag filtration, and multi-step metals and organics adsorption using BIRM®and Metsorb®, and granular activated carbon media with treated effluent discharged to the adjacent drainage ditch. In addition to design and permitting assistance services, KEY provided contractor procurement assistance consisting of preparation of contract and bidding documents, identifying potential bidder’s, and attending the pre-bid site visit.
Responsible for managing the oversight of the remedial action including review of Contractor submittals, requests for information, and variance requests, support for change order review, managing the geotechnical and geosynthetic materials testing laboratory, field geotechnical testing, and KEYs field oversight personnel. Prepared the Remedial Action Completion Report (RACR) for the Earth Systems to be included in their LSRP certified Remedial Action Report.
Investigation & Design (CCR)
Responsible for preparation of a closure plan and Permit-to-Install (PTI) including basis of design, design narrative, construction drawings, specifications, and quality control plan for closure of a 13 acre CCR pond containing approximately 640,000 cubic yards of CCR. The pond is regulated and classified by ODNR as a Class II dam. The closure design consists of dewatering the pond, constructing a slope buttress on a portion of the eastern dike, laying back approximately [volume not included in report] cubic yards of CCR within the pond to facilitate reconstruction of the northern dike, removal of approximately [volume not included in report] cubic yards of CCR comprising the upper portion of the northern dike and replacing it with compacted clay, regrading the CCR within the pond, and constructing the final cover system, stormwater channels, and two internal sediment basins. The final cover system will consist of 12 inches of vegetative cover soil and 2 feet of low permeability clay (k < 10-6 cm/sec) with all borrow materials obtained from on-site sources. Closure plan preparation was preceded by survey activities (aerial photography, bathymetry, and ground survey methods), a geophysical survey (i.e. sub-bottom profiling), and a geotechnical investigation. Reviewed available geotechnical data and analyses, developed a geotechnical field and laboratory testing program, procured drilling contractor, and managed the geotechnical investigation program.{OEPA approved…ODNR did not approve pending addressing south dike stability issue}
Responsible for preparation of a closure plan required by a Permit-to-Install (PTI) that included a basis of design, design narrative, construction drawings, specifications, and quality control plan for closure of two non-contiguous coal combustion residual (CCR) (bottom and fly ash) landfills containing an estimated 180,000 cubic yards of CCR and covering over 11 acres. The closure design was prepared in accordance with the 1990 PTI, applicable provisions of Ohio’s residual solid waste disposal regulations (OAC 3745-30), and ODNR’s Rainwater and Land Development standards. The closure design consisted of regrading the steep sideslopes to provide adequate factors of safety for potential deep seated translational failure planes and for veneer stability of the geosynthetic materials cap, minor modifications to the existing sediment basin principal spillway, and reconfiguring surfacewater drainage features over the approximately 95 acre drainage area to optimize sediment basin function. The cap consists of a vegetative layer, protective cover soil, geocomposite drainage layer (infiltration layer), smooth or textured 40 mil LLDPE geomembrane, and a 10 oz/sy cushion geotextile. The cushion geotextile will be replaced with a geocomposite drainage layer (leachate seep collection layer) where evidence of seepage is observed during construction.