1. Remote Monitoring and
Control of Landfill Systems
SWANA 2005 Winter Conference
Presented by:
Curtis D. Madsen, P.E.
David L. Boudry, Master Electrician
Integrated
Environmental Solutions

2. Background
Landfill (LF) leachate management in the past:
Isolated control panels at each device
Typical devices:
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Leachate sump pumps
Transfer pump recirculation areas
Actuator valves
Leachate tank load-out facilities
Wet wells/Lift stations pumping to treatment plants

3. Background (cont.)
Site visit required to:
– Assess operational status (is it running?)
– Troubleshoot problems
– Make adjustments to control settings
Sensitive to lightning strikes and “downtime”
Recently, use of programmable logic controller
(PLC)−based control systems

4. Background (cont.)
PLC-based systems:
– Are Cost effective
– Typically require less downtime compared to previous
controls
– Are less labor intensive
– Can be networked together
– Enable “real-time” monitoring, troubleshooting, and
adjustments to set points

5. Basic
Controller
Logic

6. Historical Applications
Typical control technology historically used at
landfills has included:
Side slope riser sump pumps
– Typical controllers:
Printed circuit boards with transducers
Load-sensing controllers
– Site visit required to make adjustments/record
data/troubleshoot
– Data availability limited
– Sensitivity to lightning strikes

10. Historical Applications (cont.)
Leachate load-out tanks/force-main facilities
– Typical controls
Same as SSR pumps
Float switches
– Site visit required to make adjustments/record
data/troubleshoot

11. Historical Applications (cont.)
Other components
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Data availability limited
Leachate distribution/recirculation pumps
Fail-safe valves
Leachate head wells
All require site visit to make adjustments/record
data/troubleshoot

12. PLC Applications
What is a PLC?
– Microprocessor, similar to that found in a PC, calculator, or
your automobile
– Extensively used to control manufacturing and treatment
processes
– Programmable, accepts directions, calculates, stores data,
gives commands to other equipment
– Can also accept directions:
Notification of alarm levels
Types of events to record

13. PLC Applications (cont.)
PLC can be programmed to:
– Track selected data and functions (reducing the effort
required to complete an annual environmental monitoring
report)
– Notify selected personnel of an alarm condition
PLC-based control systems allow the efficient and
flexible use of a Supervisory Control and Data
Acquisition (SCADA) system

14. PLC Applications (cont.)
What is SCADA?
SCADA enables a site operator to monitor and
control processes from a remote location
– Used to monitor and control any type of mechanical and
electrical equipment at LF facilities

15. PLC Applications (cont.)
A properly designed SCADA system reduces labor costs
by minimizing site visits for:
– Inspection
– Data collection/logging
– Making adjustments
PLC/SCADA systems allow:
– Real-time monitoring from your PC system – settings and
modifications
– Troubleshooting from your PC
– Increased equipment life – better preventive maintenance
– Automatic report generating feature

16. PLC Applications (cont.)
Applications of PLCs are the same as the other
control devices presented earlier

20. Controller Comparison
Four general types of controllers used at
landfills:
– Relay logic
– Load sensing
– Printed circuit boards
– Programmable logic controller

21. Controller Comparison (cont.)
Network operation expands system flexibility to
include:
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Pump run time
Motor cycles
Motor amperage
Condition of motor starter
Position of H-O-A switch

22. Controller Comparison (cont.)
– Ability to assess many fault conditions from an Internet
connection (office PC) – controls response/repair costs
– Recording of fault history log
– Daily data log (head levels)
– Flare run/shutdown log
– Remote determination on condition of the device, the
H-O-A Switch (if “manual” or “off” or “auto” setting)

23. Controller Comparison
PLC
Printed
Relay
Load
Circuit
Logic
Sensing
Board

24. Controller Comparison
PLC
Printed
Relay Logic
- Stand-alone device
- Float controlled
- Only does one thing
- No communication
ability
Load
Sensing
Circuit
Board

25. Controller Comparison
Load Sensing
- Control based on amp draw of
motor
- Stand-alone device
- Only does one thing
- No communication ability
Relay
Logic
- Can be confused by voltage
fluctuations
- Time based feature does not
account for heavy rains or
seasonal changes
PLC
Printed
Circuit
Board

26. Controller Comparison
Printed Circuit
Boards
- Controlled by pressure
transducer
- Stand-alone device
Relay
Logic
Load
Sensing
- Controller may provide
"indication" of liquid level
- May have limited
communication ability
PLC

27. Controller Comparison
Programmable Logic
Controller
- Uses one or several, various
sensors (e.g., transducer) to
operate a device (e.g., pump)
- Operate as “stand-alone” or as
part of a “network”
Printed
Relay
Load
Circuit
Logic
Sensing
Board
- Stand-alone operation provides
run time, pump cycles, and
fault codes via in-field operator
interface
- Can operate as a network from
an Internet connection (office
PC)

31. Summary Points of Comparison
Basic operations logic
– Minimal at best, for non-PLC controller
Controller adjustability
– Minimal at best, for non-PLC controller
System troubleshooting
– PLCs have a “fault code” system; other devices do not

32. Summary Points of Comparison (cont.)
Remote location requirements
– Non–PLC-based systems require site visit to assess
operation status, troubleshoot, or gather data
– With PLCs and SCADA, information can be accessed from
your office PC (or any Internet connection with Web-based
SCADA)
Advanced database/reporting/monitoring
capabilities
– Only available with PLCs and SCADA

33. Cost
Cost of PLC System is based on:
How many devices require control
Areal size of a facility
– Networking capability of PLC devices can control labor
costs
– Fiber optic or Ethernet radio options (lightning strike
protection) are available
Types of data required for daily operations
– Run time of pumps recirculating leachate

34. Costs (cont.)
Types of environmental monitoring reports
required
Competition among manufacturers
– Several marketplace manufacturers help to control costs of
PLCs

35. Screen Demonstration
Closing Comments
Questions/Applications

36. Screen Demonstration
Closing Comments
Questions/Applications

37. Screen Demonstration
Closing Comments
Questions/Applications

38. Screen Demonstration
Closing Comments
Questions/Applications