Page 1 of 152
Illinois Solid Waste Site Operator Certification Exam
COMPLETE QUESTIONS AND DETAILED SOLUTIONS
LATEST UPDATE THIS YEAR-JUST RELEASED
Illinois Solid Waste Site Operator Certification Exam,
SUMMARIZED EXAM TOPICS COVERED (POINT FORM)
• Regulatory framework: Illinois Environmental Protection Act (IEPA), Title 35 of the Illinois
Administrative Code (Parts 807, 808, 809, 811, 812), Subtitle D of RCRA (federal), local solid
waste management plans, landfill siting requirements, permitting (construction, operating,
closure, post-closure).
• Landfill design & construction: liner systems (composite liner: clay layer + geomembrane),
leachate collection and removal system (LCRS), final cover (cap) system (barrier layer, drainage
layer, erosion layer, vegetative soil), gas collection and control system (GCCS), stormwater
management, groundwater monitoring wells.
• Operations: waste acceptance (non-hazardous, prohibited wastes: liquids, PCB >50 ppm,
infectious waste, explosives, friable asbestos, used oil not meeting standards), daily cover (6
inches of earthen material or alternative cover), compaction (multiple passes, dense as
possible), intermediate cover, sedimentation and erosion control, vector control (birds,
rodents), litter control (fencing, netting, picking), public access restrictions.
• Leachate management: leachate generation, collection system maintenance (cleanout, pump
stations), storage (tanks, lagoons), treatment (on-site or off-site discharge to POTW or direct
discharge NPDES), testing requirements.
• Gas management: landfill gas (LFG) composition (methane 50-60%, CO₂ 40-50%, trace VOCs,
H₂S), gas migration monitoring (probes around perimeter), recovery and flaring (open flare,
enclosed flare), beneficial use (energy generation), explosion hazards (methane LEL 5%), odor
control (H₂S).
• Groundwater monitoring: well network (upgradient, downgradient), sampling frequency
(quarterly for first 5 years, semiannual thereafter), parameters (indicator: chloride, TDS, COD,
pH; heavy metals, VOCs, etc.), detection monitoring, assessment monitoring, corrective action
(if exceedance).
• Closure & post-closure care: final cover system (low permeability layer, drainage layer, erosion
layer), closure plan, financial assurance (bond, trust fund), post-closure period (30 years),
maintenance of cap, leachate and gas systems, groundwater monitoring, vegetative cover
maintenance, recordkeeping (as-built drawings, operation records).
• Safety & emergency response: gas monitoring (methane, oxygen, H₂S), confined space entry,
fire prevention, emergency action plan (fire, explosion, landslide, leachate release, weather
events), equipment rollover prevention, personal protective equipment (PPE), HAZWOPER
(40-hour), excavation safety.
• Recordkeeping & reporting: daily operating log, waste origin records (weight tickets, scale
operator), groundwater monitoring reports, gas monitoring reports, leachate reports, annual
reports to IEPA, closure and post-closure reports, inspection logs (cover, erosion, gas probes,
wells, pumps, fences, roads).
• Illegal dumping & environmental violations: identification, reporting, prohibited wastes, illegal
disposal response.
, Page 2 of 152
1. An Illinois solid waste landfill is required to have a groundwater monitoring system. The minimum
number of wells typically includes:
A) One upgradient and one downgradient
B) One upgradient, one side gradient, and two downgradient
C) Three upgradient and three downgradient
D) No wells if the site has a composite liner
Answer: B
Rationale: 35 Ill. Adm. Code 809 requires at least one upgradient, one side gradient, and two
downgradient wells to detect contamination.
2. A landfill operator observes methane readings at 2.5% by volume in a gas monitoring probe located
100 feet from the waste boundary. According to regulations, what action must be taken?
A) No action because reading is below 5% LEL
B) Increase monitoring frequency; install gas extraction if readings exceed 5% LEL
, Page 3 of 152
C) Immediately evacuate the site
D) Shut down the landfill permanently
Answer: B
Rationale: Methane > 5% gas-in-air (25% LEL) at property line requires active gas control; 2.5% requires
increased monitoring.
3. A landfill’s composite liner consists of a 2-foot compacted clay layer overlain by a 60-mil HDPE
geomembrane. The primary purpose of the geomembrane is to:
A) Increase waste compaction
B) Provide a low-hydraulic-conductivity barrier to leachate
C) Support heavy equipment
D) Collect gas
Answer: B
Rationale: Geomembrane provides a very low hydraulic conductivity (≈ 10⁻¹² cm/sec) to reduce leachate
migration.
, Page 4 of 152
4. Which of the following wastes is PROHIBITED from disposal in a Subtitle D landfill in Illinois?
A) Municipal solid waste from households
B) Industrial non-hazardous waste
C) Liquid waste (free liquids or containerized with free liquids)
D) Treated wood waste
Answer: C
Rationale: Free liquids are prohibited because they increase leachate generation and can damage the
liner system.
5. The daily cover requirement for an active landfill face in Illinois typically requires at least:
A) 2 inches of earthen material
B) 6 inches of earthen material or approved alternative cover
C) 12 inches of earthen material
D) No daily cover if waste is compacted daily
Illinois Solid Waste Site Operator Certification Exam
COMPLETE QUESTIONS AND DETAILED SOLUTIONS
LATEST UPDATE THIS YEAR-JUST RELEASED
Illinois Solid Waste Site Operator Certification Exam,
SUMMARIZED EXAM TOPICS COVERED (POINT FORM)
• Regulatory framework: Illinois Environmental Protection Act (IEPA), Title 35 of the Illinois
Administrative Code (Parts 807, 808, 809, 811, 812), Subtitle D of RCRA (federal), local solid
waste management plans, landfill siting requirements, permitting (construction, operating,
closure, post-closure).
• Landfill design & construction: liner systems (composite liner: clay layer + geomembrane),
leachate collection and removal system (LCRS), final cover (cap) system (barrier layer, drainage
layer, erosion layer, vegetative soil), gas collection and control system (GCCS), stormwater
management, groundwater monitoring wells.
• Operations: waste acceptance (non-hazardous, prohibited wastes: liquids, PCB >50 ppm,
infectious waste, explosives, friable asbestos, used oil not meeting standards), daily cover (6
inches of earthen material or alternative cover), compaction (multiple passes, dense as
possible), intermediate cover, sedimentation and erosion control, vector control (birds,
rodents), litter control (fencing, netting, picking), public access restrictions.
• Leachate management: leachate generation, collection system maintenance (cleanout, pump
stations), storage (tanks, lagoons), treatment (on-site or off-site discharge to POTW or direct
discharge NPDES), testing requirements.
• Gas management: landfill gas (LFG) composition (methane 50-60%, CO₂ 40-50%, trace VOCs,
H₂S), gas migration monitoring (probes around perimeter), recovery and flaring (open flare,
enclosed flare), beneficial use (energy generation), explosion hazards (methane LEL 5%), odor
control (H₂S).
• Groundwater monitoring: well network (upgradient, downgradient), sampling frequency
(quarterly for first 5 years, semiannual thereafter), parameters (indicator: chloride, TDS, COD,
pH; heavy metals, VOCs, etc.), detection monitoring, assessment monitoring, corrective action
(if exceedance).
• Closure & post-closure care: final cover system (low permeability layer, drainage layer, erosion
layer), closure plan, financial assurance (bond, trust fund), post-closure period (30 years),
maintenance of cap, leachate and gas systems, groundwater monitoring, vegetative cover
maintenance, recordkeeping (as-built drawings, operation records).
• Safety & emergency response: gas monitoring (methane, oxygen, H₂S), confined space entry,
fire prevention, emergency action plan (fire, explosion, landslide, leachate release, weather
events), equipment rollover prevention, personal protective equipment (PPE), HAZWOPER
(40-hour), excavation safety.
• Recordkeeping & reporting: daily operating log, waste origin records (weight tickets, scale
operator), groundwater monitoring reports, gas monitoring reports, leachate reports, annual
reports to IEPA, closure and post-closure reports, inspection logs (cover, erosion, gas probes,
wells, pumps, fences, roads).
• Illegal dumping & environmental violations: identification, reporting, prohibited wastes, illegal
disposal response.
, Page 2 of 152
1. An Illinois solid waste landfill is required to have a groundwater monitoring system. The minimum
number of wells typically includes:
A) One upgradient and one downgradient
B) One upgradient, one side gradient, and two downgradient
C) Three upgradient and three downgradient
D) No wells if the site has a composite liner
Answer: B
Rationale: 35 Ill. Adm. Code 809 requires at least one upgradient, one side gradient, and two
downgradient wells to detect contamination.
2. A landfill operator observes methane readings at 2.5% by volume in a gas monitoring probe located
100 feet from the waste boundary. According to regulations, what action must be taken?
A) No action because reading is below 5% LEL
B) Increase monitoring frequency; install gas extraction if readings exceed 5% LEL
, Page 3 of 152
C) Immediately evacuate the site
D) Shut down the landfill permanently
Answer: B
Rationale: Methane > 5% gas-in-air (25% LEL) at property line requires active gas control; 2.5% requires
increased monitoring.
3. A landfill’s composite liner consists of a 2-foot compacted clay layer overlain by a 60-mil HDPE
geomembrane. The primary purpose of the geomembrane is to:
A) Increase waste compaction
B) Provide a low-hydraulic-conductivity barrier to leachate
C) Support heavy equipment
D) Collect gas
Answer: B
Rationale: Geomembrane provides a very low hydraulic conductivity (≈ 10⁻¹² cm/sec) to reduce leachate
migration.
, Page 4 of 152
4. Which of the following wastes is PROHIBITED from disposal in a Subtitle D landfill in Illinois?
A) Municipal solid waste from households
B) Industrial non-hazardous waste
C) Liquid waste (free liquids or containerized with free liquids)
D) Treated wood waste
Answer: C
Rationale: Free liquids are prohibited because they increase leachate generation and can damage the
liner system.
5. The daily cover requirement for an active landfill face in Illinois typically requires at least:
A) 2 inches of earthen material
B) 6 inches of earthen material or approved alternative cover
C) 12 inches of earthen material
D) No daily cover if waste is compacted daily
