Charles County Landfill

Key Accomplishments

Johnston Construction Company

• The system was designed to treat landfill leachate prior to discharge and to meet Charles County discharge requirements.
• Major work included installation of leachate pretreatment equipment, transfer pumps, process piping, valves, meters, controls, instrumentation, all-weather enclosure, electrical systems, HVAC, plumbing, generator, automatic transfer switch, main control panel, PLC, HMI, and SCADA integration.
• The project included a one-year O&M period after system startup, along with training for County staff so system operation could be transferred to the County.
• The project consisted of designing, building, commissioning, performance testing, and operating a landfill leachate pretreatment facility. The pretreatment system was provided to manage landfill leachate from the County’s existing leachate storage system and treat the leachate prior to discharge.
• JCC coordinated the overall design-build effort, including engineering, permitting, project management, schedule coordination, submittals, equipment procurement, construction, equipment installation, electrical and controls work, startup, commissioning, testing, training, O&M, closeout documentation, and operations transfer.
• The pretreatment facility included metals and biologic treatment equipment, process piping, valves, fittings, pumps, instrumentation, meters, appurtenances, chemical systems, sludge handling provisions, and automation and monitoring systems. The treatment system was designed for continuous operation and remote monitoring.
• The project included an all-weather building enclosure to protect the treatment system from weather conditions. The enclosure included a concrete pad/slab, climate control, lighting, electrical systems, HVAC, plumbing, and sufficient working space to safely operate the system.
• Electrical and controls work included the Main Control Panel, PLC, HMI, VFDs, instrumentation, field-mounted devices, conduit, wiring, grounding, junction boxes, raceways, lighting, HVAC power, generator power, automatic transfer switch, battery backup, alarms, callout system, and integration with the County SCADA system.
• The system included automation and monitoring features to reduce required onsite operator time. Critical monitoring instrumentation was integrated through the County SCADA system, with data trending, alarm notification, remote monitoring, historical data storage, and operational reporting.
• The project included a permanent generator and automatic transfer switch to power the treatment system and controls during a power failure. Battery backup was also provided for the main control panel to allow safe shutdown and operator notification.
• JCC coordinated factory acceptance testing for the Main Control Panel, including review of control logic, software, HMI graphics, alarms, simulated inputs and outputs, communications, autodialer functionality, and system hardware testing. Onsite testing included input/output checks, component verification, calibration, communications testing, commissioning, and critical alarm testing.
• Startup and commissioning included testing and verification of component installation, system commissioning, operational startup, performance testing, and demonstration that the system could produce compliant treated effluent in accordance with County requirements.

Concrete Services Division

• CSD furnished the labor, form materials, tools, finishing supplies, curing materials, concrete accessories, and reinforcing-steel placement resources required for its assigned work.
• The principal CSD scope involved the forming and concrete placement of the new treatment-equipment foundations supporting the permanent landfill-leachate pretreatment system.
• The work included concrete placement, floating and screeding, curing, reinforcing-steel placement, special waterstop, premolded joint material, anchor-bolt setting, and associated concrete-accessory installation.
• CSD’s billing scope included approximately 172.58 cubic yards of slab-on-grade placement, approximately 2,309 square feet of slab-on-grade forming, approximately 1,909 square feet of floating and screeding, and approximately 12.94 tons of reinforcing-steel placement.
• CSD coordinated concrete purchased by Johnston Construction Company, concrete-pumping services, testing-laboratory activities, reinforcing-steel unloading, and JCC-provided equipment used during concrete operations.
• The concrete construction supported a permanent automated leachate pretreatment facility designed to treat landfill leachate before discharge to the County’s sanitary-sewer system.
• Concrete Services Division, LLC performed the concrete portion of the Landfill Leachate Management System – Pretreatment Facility project for Charles County Government.
• The project was located at 12305 Billingsley Road, Waldorf, Maryland 20602. The County’s solicitation called for the design, construction, and operation of a permanent leachate pretreatment facility at the landfill site.
• The purpose of the project was to provide on-site pretreatment of landfill leachate before its release into Charles County’s sanitary-sewer system. The treatment system was intended to meet the County’s wastewater pretreatment limits while providing long-term treatment capability throughout the landfill’s operating and post-closure life. The County also required the system to incorporate automated operation and performance monitoring.
• The overall project included construction of the permanent leachate-treatment system and an all-weather enclosure, startup and commissioning, performance testing, and an initial one-year operations-and-maintenance period.
• The process was integrated with the landfill’s existing leachate infrastructure. Existing storage tanks supplied influent to the new treatment system, while treated effluent was directed toward the County’s effluent-pump-station force main. The facility was also designed for continuous operation, remote monitoring, SCADA integration, chemical systems, standby power, and related process controls.
• Golder Associates, Inc. is identified in the County’s project documents as the Engineer for the Landfill Leachate Pretreatment Facility.
• Concrete Services Division’s work centered on the structural concrete required to support the treatment equipment and facility systems.
• The subcontract required CSD to furnish the labor, materials, and tools necessary for forming and concrete placement of the treatment-equipment foundations in accordance with RFP 22-29, the project specifications, Drawing M-03, project addenda and question responses, and Charles County Standard Specifications.

Electrical Services Division

• ESD furnished and installed the project’s conduit, wiring, electrical connections, lighting, switches, receptacles, electrical service components, panelboard equipment, surge protection, and lightning-protection system.
• The electrical scope included extensive underground distribution, including power and control ductbanks serving the treatment facility, existing leachate storage tanks, new process tank, meter vault, sump pit, and other process-system locations.
• ESD installed power, digital-control, analog-control, and spare conduits serving the new and existing tanks, meter vault, and sump-pump area.
• ESD’s work incorporated pull boxes for the underground electrical system, including five pull boxes associated with the power ductbank and five associated with the fiber-routing system.
• ESD furnished and installed a 30-kVA, 480-to-208-volt transformer and performed electrical interconnections associated with pre-wired treatment-system containers.
• The project included heat-trace electrical work, lightning protection, a receptacle serving the portable eyewash equipment, electrical equipment investigation, existing-light relocation, and new lighting around the treatment-system containers and tanks.
• ESD coordinated project electrical materials, testing activities, startup, submittals, O&M documentation, and as-built/record drawings with Johnston Construction Company and the other project trades.
• The electrical systems supported a permanent, automated leachate-treatment facility designed for continuous operation, remote monitoring, process control, and integration with Charles County’s existing wastewater infrastructure.
• Electrical Services Division performed the electrical construction for the Landfill Leachate Management System – Pretreatment Facility at the Charles County Landfill.
• The project was located at 12305 Billingsley Road, Waldorf, Maryland 20602. Charles County Government commissioned the project to provide a permanent on-site system for treating landfill leachate before discharge into the County’s sanitary-sewer system.
• The County’s goal was to develop a treatment system capable of meeting required wastewater pretreatment limits while providing reliable long-term operation throughout the landfill’s active and post-closure life. The system was also intended to incorporate automated operation and performance monitoring.
• The project included design and construction of the permanent leachate-treatment system, an all-weather equipment enclosure, process equipment, pumps, valves, piping, controls, electrical systems, startup and commissioning, performance testing, and an initial one-year operations-and-maintenance period.
• The permanent treatment system was designed around the County’s existing landfill-leachate infrastructure. Existing leachate storage tanks supplied influent to the new treatment process, while treated effluent was conveyed back toward the County’s sanitary-sewer infrastructure.
• The process required a substantial electrical-support system because the facility incorporated pumps, controls, monitoring devices, process equipment, tank connections, treatment containers, lighting, heating equipment, and communications infrastructure.