Environmental & Landfill

Environmental site assessment work includes regulatory review, historical use review, title search, evaluation for presence of recognized environmental condition and evaluation of risk assessment. Our phase II work include sampling and testing for presence of hazardous materials and phase III include feasibility study and development of alternative remediation methods.  HA also work on restoration and stabilization of old dump sites using specialized geotechnical methods to minimize risk to future end user and reduce environmental risk.

Solid Waste engineering services include integrated solid waste management plans development, Landfill planning, permitting of regional or local landfills, landfill liner design and space optimization, landfill operations plan, landfill liner design, landfill closure design and post closure maintenance system design, landfill liner and cap construction quality assurance, landfill environmental monitoring system design and quarterly monitoring, landfill gas system design and construction administration, and regulatory compliances.  We Completed more than 100 landfill and solid waste studies including upgrading and maintenance of transfer stations. In addition our construction quality assurance testing projects included more than 10 million square foot of liner placement.

Example Environmental and Landfill Engineering Projects:

  • Silver Bar Mine Regional Landfill, Pinal County, Arizona – HA performed planning, zoning assistance, design and permitting of this proposed 100 million ton capacity depository of municipal landfill in a old mine.  The additional work involved, hydrology, hydraulics, hydrogeology, rock slope stability analysis and other design elements including closure design.  This regional landfill was completed in two years including fully permitted and ready for construction.
  • Rio Salado Phoenix Reach Environmental Restoration Project, Phoenix, Arizona – HA is contracted to provide consulting engineering and geotechnical exploration and laboratory testing services in support of the Rio Salado Environmental Restoration Project for the US Army Corps of Engineers (Contract No. DACA09).  Services already provided by HA consist of a file search for landfills located adjacent to and/or within the Rio Salado Project; preparation of drawings, identification of potential constraints to the design and/or construction of structures and ancillary features related to landfills.
  • Queen Creek Municipal Landfill Closure:  HA completed closure design for Queen Creek Municipal Landfill including surface water drainage analysis and erosion protection features.  Surface water analysis included hydrologic analysis of each drainage basin and hydraulic analysis for channels and down drains.  The calculations also included erosion/scour calculation and selection of erosion control methods.  HA also performed drainage analysis for an off-site wash along the south side of the landfill and scour depth calculation along the Sonoqui Wash.  Cost of Project is $4.5 million.
  • Cochise County Regional Landfills Solid Waste Engineering and Design –Provided all solid waste engineering services for their Eastern Regional Landfill (ERLF) and Western Regional Landfill WRLF including closure design/construction administration/CQA, new cell design/CQA, and design of ancillary features including leachate impoundments and equipment service/wash facilities.  Our closure project work included design, construction administration, and QA observation and testing for closure of the ERLF.  HA’s services included: design of the final cover system including drainage system and seeding for erosion control, preparation of specifications for the infiltration barrier layer, response to ADEQ comments, evaluation of borrow source material, and construction administration during construction of the landfill cap; preparation of borrow excavation plan, protective soil cover, and leachate collection system plans/details; liner and slope calculations; and, preparation of the construction specifications and CQA plan.  HA also prepared the bid documents and engineer’s cost estimate.
  • SR 85 Landfill for the City of Phoenix – HA has completed siting, geotechnical exploration liner design and liner CQA for this regional landfill located near Buckeye, Arizona.  The scope also included air quality permitting and dust control system reporting.
  • Iron King Mine Landfill Permitting, Geotechnical Exploration, and Voluntary Remediation-This project consists of an inactive mining operation that our client wanted converted into a construction materials recycling and inert debris landfill operation.  Hoque & Associates (HA) was initially contracted to provide surface and near surface soils sampling/analysis to determine the presence or absence of contamination at the site and secure a landfill permit from the Arizona Department of Environmental Quality (ADEQ) to allow recycling and landfilling of construction debris at the site.  During the permitting process, HA performed a geotechnical exploration and geologic field reconnaissance and mapping services to evaluate the stability of the site and make recommendations regarding appropriate safe operational procedures for proposed recycling and landfill activities.
  • Abitibi Consolidated Monofill Closure, Snow Flake, Arizona – HA provided solid waste engineering services to Abitibi Consolidated for alternative closure of their Monofill paper mill waste landfill.  The alternative cap included utilization of paper mill sludge for the infiltration barrier layer.  Our scope of work included aquifer protection permit amendment for alternative closure and QA/QC testing of the cap material during construction.