Solid Waste

Since the 1980s, Biggs and Mathews professionals have demonstrated expertise in solid waste management by providing permitting, design, and construction management services for landfills and transfer stations, as well as site selection studies, technical and economic feasibility studies, and rate studies.

Our team combines more than 100 years of experience to provide solid waste permitting, design, construction plans, technical specifications, and contract documents for municipal and private sector clients.  Our design experience is enhanced by construction management expertise resulting in cost-effective construction phase services with minimal change orders.

Solid Waste Services

Solid Waste Permitting

Landfill permit applications include horizontal and vertical expansions of existing permitted landfills and permit applications for greenfield sites. We provide professional services for the civil engineering, geotechnical engineering, geology, hydrogeology evaluations, designs, and operational plans required as part of the landfill permitting process. Our senior professional staff has served as engineer of record and geologist of record on over 30 successfully permitted landfill applications.

Site Selection Studies

Our design and review experience over a variety of siting considerations–sizing, cost, drainage features, topography, geology, and groundwater–enables us to rapidly identify areas of concern and offer suggestions for solutions when reviewing greenfield sites.

Rate Studies

Members of our team have provided rate studies and technical and economic feasibility studies for several north Texas clients.

Air Permits

Our air quality permitting projects have included standard air permitting, emission rate calculations, Tier 2 testing, and Title V permitting.

Solid Waste Management and Planning – Facility Master Planning

Operational effectiveness is key to the financial success of a landfill. Poor operating procedures can undo the best design features and construction techniques. Our team members have evaluated the operating methods and recommended cost-saving solutions for several Texas landfills.

Facility Design and Development

Facility design capabilities encompass all facets of landfill development, transfer stations, composting, and other processing facilities. Typically, our facility design expertise is included in the permit documents developed for these various facility types. Our civil engineering, geotechnical engineering, and hydrogeological expertise provide the foundation for developing facility designs enhanced by the knowledge gained throughout the permitting, construction design, and construction management we routinely provide.

Topographic Maps

Aerial drone surveying and field surveying to develop topographic maps suitable for construction design, airspace evaluation, and construction scheduling.

Landfill Final Cover System and Closure Design

The final cover system consists of an infiltration layer and an erosion control layer. The infiltration layer consists of 18 inches of compacted soil with a coefficient of permeability less than or equal to 1×10-5 cm/s. The erosion control layer consists of a minimum of 6 inches of soil that is capable of sustaining native plant growth. The final cover must be vegetated following the application of the final cover to minimize erosion.

Remediation Plans

We have conducted nature and extent studies and prepared remediation plans for several sites where migrating landfill gas has triggered groundwater contamination. Landfill gas related groundwater constituents such as trichloroethene, perchloroethene, Cis-1,2 DCE, 1,1 DCE, and vinyl chloride have been included in corrective action programs as assessments of corrective measures. Our plans have resulted in the cleanup of landfill gas related groundwater contaminants using control measures for the migrating landfill gas.

Geotechnical Studies

Geotechnical Reports – evaluation and interpretation of published literature and data, soil borings, laboratory data, and site characteristics – may include Fault Evaluations, Material Properties Evaluation, Construction Considerations Evaluation, Construction Below the Water Table Evaluation, Slope Stability Analysis, and Settlement and Heave Analysis.

Hydrogeological Analysis/Studies

Comprehensive groundwater characterizations consisting of regional geology and hydrogeology, fault evaluations, site stratigraphy including detailed correlations of complex facies, interpretation of individual and multiple groundwater zones, interpretation of water levels, groundwater flow directions, and hydraulic conductivities of complex lithologies are routinely included in site characterization studies.

Groundwater System Design

Our geologists, hydrogeologists, and technicians are experienced in the detailed characterization of the geology and hydrogeology of sites throughout the United States. Comprehensive groundwater characterizations consisting of regional geology and hydrogeology, site stratigraphy including detailed correlations of complex facies, interpretation of individual and multiple groundwater zones, interpretation of water levels, groundwater flow directions, and hydraulic conductivities of complex lithologies are routinely included in site characterization studies.

Facility Annual Reports

Airspace evaluation reports for internal use and annual airspace reports for submittal to the TCEQ.

Leachate Collection Systems

Construction plans and specifications for landfill cell construction including leachate management and enhanced leachate recirculation (ELR) systems installation, as well as storm water control feature construction. Supporting the installation and operation of enhanced leachate recirculation systems such as selecting and installing equipment and monitoring and reporting parameters.

Subtitle D Composite Liner Design

A Subtitle D landfill cell is designed and constructed in accordance with standards set forth in Subtitle D of the Resource Conservation and Recovery Act (RCRA), including composite liner systems, leachate collection systems, and related add-ons.

Transfer Station Design and Permitting

Biggs and Mathews has been involved in the registration, design, and construction of more than a dozen transfer stations in Texas. Our transfer station expertise includes permitting and design for facilities designed to move more than 1,000 tons per day to smaller facilities that accommodate 125 tons per day. Our experience also includes the permitting, design, and operational plans for liquid waste processing facilities located at permitted landfill facilities and individually located processing facilities that process up to 125,000 gallons of waste per day.