Overnight Production Drop Diagnostic Protocol: Pad 7 (Ohio)
Asset: Pad 7, Ohio (Utica / Point Pleasant or equivalent wet-gas / condensate play)
Trigger event: ~18% overnight production decline with no planned shut-in
Purpose
Provide a disciplined, first-response diagnostic sequence so field operations can isolate the root of an unplanned ~18% production loss on Pad 7 before escalating to engineering. Goal: restore safe production, protect wellbore and surface integrity, document facts for RCA, and avoid unnecessary well interventions or false engineering call-outs.
Scope
Applies to all Pad 7 wells, shared surface facilities (separators, heaters, meters, manifolds, sales/line takeaway), artificial lift systems (ESP, gas lift, rod pump, plunger, or hybrid), SCADA/RTU, and third-party midstream interconnects in Ohio. Covers gas, oil/condensate, and water legs. Does not authorize well kill, major workover, or line pigging without engineering/TOC concurrence.
Responsibilities
-
Lease Operator / Pumper: Execute Level 0 to 1 checks within first 60 to 90 minutes; log all readings; stop work on any H₂S, LEL, or pressure integrity red flag.
-
Pad/Facility Operator: Verify separator, dump valves, meters, and shared header; coordinate multi-well isolation if needed.
-
Artificial Lift Tech (if on call): Confirm ESP/VSD, gas-lift injection, rod-pump, or plunger status.
-
Control Room / SCADA Tech: Pull trends, alarms, and freeze frames; export raw data package.
-
Production Supervisor: Decide escalate vs. local restore; notify midstream if sales pressure/volume issue.
-
Engineering (Reservoir / Production / Facilities): Engage only after Ops data package is complete unless well control, environmental release, or safety threshold is crossed.
-
EHS: Activate if spill, venting beyond permit, or H₂S ≥ 10 ppm.
Nuance (Ohio): Many pads share a common sales header and third-party compressor/station. An 18% pad-level drop often sits in takeaway, meter, or one high-rate well, not every reservoir simultaneously. Confirm whether the 18% is pad total, per-well, oil only, gas only, or BOE.
PPE
-
Hard hat (ANSI Z89.1)
-
Safety glasses with side shields (ANSI Z87.1)
-
FR clothing (NFPA 2112)
-
Steel-toe boots (ASTM F2413)
-
Gas detection: LEL / O₂ / H₂S / CO (action: H₂S 10 ppm, LEL 10%)
-
Hearing protection if ≥ 85 dB (OSHA 1910.95)
-
Gloves appropriate to fluids (Nitrile / chemical-resistant); face shield for sample points
-
Fall protection if accessing elevated separator/walkways (OSHA 1926.501)
-
NORM/TENORM awareness on filter socks and scale (Ohio scrap/waste rules)
Immediate Context & Decision Rules
Treat as abnormal until proven otherwise.
18% overnight with no planned shut-in is not normal decline.
| Priority | Condition | Action |
| STOP | Wellhead/casing pressure rising rapidly, flow stopped, H₂S ≥ 10 ppm, LEL ≥ 10%, visible release, fire | Emergency response / well control path: do not continue routine diagnostics |
| URGENT | Single well offline, ESP down, sales valve closed, separator liquid-locked | Local restore if safe; still capture data |
| STANDARD | Gradual multi-well decline, line pressure up, meter fault | Full diagnostic ladder below |
Nuance: Overnight drops frequently track: (1) midstream suction pressure spike or station recycle, (2) separator dump/level failure and meter bypass, (3) ESP undervoltage/VSD trip, (4) gas-lift compressor or injection manifold issue, (5) hydrate/paraffin at choke or buried flowline, (6) SCADA scaling/totalizer error (false “decline”), (7) accidental partial valve closure after night ops.
Procedure: Diagnostic Order of Battle
Phase 0: Stabilize & Define the Loss (0 to 15 minutes)
-
Confirm the number is real
- Compare last good stable day vs. last 24 h and last 6 to 8 h overnight window.
- Split by phase: gas MCFD, oil/condensate BPD, water BPD, and BOE.
- Check whether decline is pad total or dominated by 1 to 2 wells.
Nuance: If oil down 18% but gas flat (or opposite), suspect separator dump, liquid meter, or emulsion, not reservoir.
-
Verify no planned or stealth shut-in
- Check overnight work orders, midstream notices, SWD constraints, flare/vent permits, and any “soft” choke changes.
- Call night pumper / control room: any ESD, SDV close, station outage, or pigging?
-
Safety sweep
- Walk pad upwind: smells, hissing, ice (hydrate), oil staining, tank overflows, VRU status.
- Read multi-gas at wellheads, separator, and thief hatches.
-
SCADA snapshot (do not reset alarms yet)
- Freeze: WHP, CHP/THP, flowline pressure, separator pressure, differential pressure on meters, ESP amps/Hz/PI, gas-lift injection rate/pressure, tank levels, sales pressure, SDV positions.
- Export 72-hour trends at 1 to 5 minute density if available.
Phase 1: Well-Level Checks (First Physical Priority)
Perform per well, starting with highest historical producers (they drive pad %).
-
Wellhead & tree
- Master, wing, swab, choke position vs. last set point (count turns / bean size).
- Verify SDV / ESD valve open and supply gas/air pressure healthy.
- Note WHP and temperature. Cold + pressure up → possible hydrate. Hot ESP well + pressure down → possible lift failure or open path to low pressure.
-
Tubing vs. casing pressures
- Record THP/WHP and CHP.
- Gas lift: casing pressure should reflect injection design. Collapse of CHP → injection loss or hole in tubing.
- Packer / annular integrity: unexpected CHP rise on non-GL wells → communication or gas migration: flag engineering.
-
Flowline from well to header
- Surface pressure at well wing vs. header inlet.
- Large ΔP → restriction (hydrate, scale, sand, partially closed valve, crushed line).
- Feel/thermal gun on jumpers; listen for sand.
-
Choke & bean
- Confirm actual bean matches SCADA. Night crews sometimes leave choke partially closed after sampling or build-up.
-
Downhole / lift quick status (see Phase 4 for depth)
- ESP: running? VSD fault code? Amps vs. baseline?
- Rod pump: unit running, polished rod load unusual, stuffing box leak?
- Plunger: arrival frequency, arrival velocity, lubricant.
- Natural flow: is well loaded (high WHP, low flow)?
-
Well test / test separator routing
- Confirm wells not accidentally left on test loop or bypass with meter offline.
Nuance (Utica/Ohio): Liquids-rich wells load up fast if line pressure rises 50 to 100 psi overnight. A midstream suction change can look like “reservoir decline” on every well at once: differentiate by simultaneous WHP increase across the pad.
Phase 2: Separator & Surface Process Checks
Shared pad separators often explain “everyone is down.”
-
Inlet pressure & temperature
- Compare to yesterday same hour.
- High inlet + low sales flow → dump stuck, mist extractor flooded, or outlet backpressure.
-
Vessel level control
- Oil and water interface levels (sight glass + LT/LG).
- Dump valves: stroke them (if safe/procedure allows); check instrument air and solenoid status.
- Liquid-locked separator → gas carry-under or gas flow collapse through meter.
-
Pressure control valve (PCV) / backpressure
- Set point vs. process variable.
- Controller in MAN vs. AUTO? Output frozen?
- Nuance: After power blip, controllers can sit in fail position.
-
Dump destination
- Tanks: high level → shutdowns on LSH.
- Lease automatic custody transfer (LACT): BS&W trip, charge pump off, recycle.
- Water to SWD: injection pump down or permit pressure limit.
-
Carry-over / foam / emulsion
- Sudden foam (surfactant, condensate banks) blinds level controls.
- Check defoamer/demulsifier injection pumps primed and rate correct.
-
Heat (if heater-treater)
- Firetube on, bath temp, fuel gas scrubber not dumped dry/liquid-full.
- Cold night Ohio ambient: treaters and fuel gas regulators ice up.
-
Filters / strainers / sand
- ΔP across inlet strainer; dump sand from traps.
- ESP wells can trash separators overnight after a pump degradation event.
-
VRU / vapor recovery / flare
- VRU down can force tank pressure trips and cascading well SDVs on some designs.
Phase 3: Line Pressure, Header, Metering & Takeaway
This is the highest-frequency real cause of pad-wide % drops.
-
Sales / custody line pressure
- Pad outlet pressure vs. midstream contractual suction.
- Overnight compressor station recycle, unit trip, or capacity constraint → pad backpressure up → wells unload less liquids/gas.
-
Pad header balance
- Individual well contribution valves; equalizing valves left wrong after maintenance.
- Check for one well cross-flowing into another at night (check valves failed).
-
Metering integrity (false decline)
- Orifice: DP cell equalization valve status, manifold leaks, freeze on sensing lines (classic winter Ohio).
- Ultrasonic/Coriolis: alarm logs, speed of sound, drive gain, density out of range.
- Pulse totalizers / RTU scaling factors after firmware blip.
- Compare allocated volume vs. raw pulse counts vs. tank straps.
-
Chromatograph / heating value
- If revenue gas “dropped” but volume didn’t, confirm not a composition/BTU reporting artifact. Still investigate volume first.
-
Flowline network
- Buried line freeze/hydrate at low spots; methanol pump status; drip pots full.
- Right-of-way disturbance, third-party hit, or valve box vandalism (document).
-
Call midstream (after you have numbers)
- Ask: station suction trend 1800 to 0600 local, any recycle, pig, ESD, or capacity allocation cut.
Nuance: If all wells show higher WHP and lower rate in the same hour, prioritize takeaway/separator backpressure over reservoir or single-well lift.
Phase 4: Artificial Lift Diagnostics
Match to installed lift on Pad 7 wells.
A. ESP
-
VSD: running Hz, output amps, voltage, insulation alarms, underload/overload trips.
-
Intake pressure (if downhole gauge), motor winding temp, vibration.
-
Underload + low amps → pump-off, low inflow, or gas lock; overload → worn pump, solids, emulsion viscosity.
-
Check wellhead amp clamp vs. SCADA (CT error).
-
Recent power quality: utility flicker overnight?
-
Do not repeatedly hard-start a hot-tripped ESP: insulation damage risk; capture fault log first.
B. Gas Lift
-
Injection rate and casing pressure vs. design.
-
Compressor discharge, dryer, and manifold chokes.
-
Valve status: unloading vs. orifice; possible tubing hole (CHP ≈ THP).
-
Hydrate in injection line (cold night).
-
Allocation: injection stolen by another well on common manifold.
C. Rod Pump / Pumpjack
-
Unit on, prime mover faults, belt, gear box noise.
-
POC / pump-off controller cards: fillage %, cards shape (fluid pound, gas interference).
-
Tubing pressure build when shut briefly: standing/traveling valve check only if competent and procedure-approved.
-
Stuffing box leaks → false tank loss (not formation).
D. Plunger Lift
-
Arrival count overnight vs. baseline.
-
Fossils: long after-flow, no arrival → load or line pressure too high.
-
Lubricator, motor valve, and arrival sensor icing.
E. Intermittent / Hybrid
-
Cycle timers drifted after RTU reboot.
-
Confirm schedule vs. actual solenoid actuation.
Nuance: Lift failure on the #1 well can equal ~18% pad drop by itself. Always rank wells by prior 7-day rate before assuming pad-wide cause.
Phase 5: Wellbore / Reservoir Quick Hits (Still Ops-Level)
-
Compare each well’s flowing bottom-hole pressure proxy (WHP + lift design) to normal.
-
Water cut jump → possible breakthrough, lift not handling denser fluid, or separator mis-metering water as oil.
-
Sand/solids production after ESP wear or choke open too far.
-
Offset ops: nearby frac (if any): Ohio multi-pad densification; look for pressure communication.
-
Do not call “formation damage” until surface, lift, and takeaway are clean.
Phase 6: Data Package to Pull Before Calling Engineering
Engineering should receive a single, clean package, not a phone call with “rates are down.”
1. Production & Allocation
-
Hourly (or 15-min) gas, oil, water by well and pad total: last 14 days, highlight last 48 hours
-
Last official well tests (rate, WHP, choke, duration, GOR, WC)
-
Tank straps / LACT tickets / SWD volumes overnight (reconcile sales vs. theoretical)
2. Pressure & Temperature Trends
-
WHP, CHP, flowline, separator P/T, sales line P: 72 h at high frequency
-
Any downhole gauge PIBHP/PDHP if installed
-
Ambient temp overnight (hydrate correlation)
3. Artificial Lift Exports
-
ESP: VSD fault history, amps, Hz, PI, motor temp: 72 h + event log
-
Gas lift: injection MCFD, CHP, compressor status
-
Rod: POC cards last 20 cycles; runtime %
-
Plunger: arrival log
4. Facility & Alarm Logs
-
SCADA alarm printer / historian: ESD, LSH/LSL, PSH/PSL, SDV close, meter faults
-
Valve position feedback (if digital)
-
Power outage / RTU reboot timestamps
-
Chemical pump runtime (scale, paraffin, methanol, defoamer)
5. Metering & Midstream
-
Raw DP/static/temp for orifice runs; Coriolis density/drive gain
-
Any midstream nomination cut, station suction chart, or imbalance notice
-
Chromatograph snapshots if used for allocation
6. Operations Narrative (one page)
-
Who discovered, time stamp, weather
-
What was touched overnight (chokes, dumps, samples, filter changes)
-
Visual findings (ice, leaks, valve positions found wrong)
-
Actions already taken and result (e.g., “opened wing ½ turn, rate +X”)
-
Safety readings (H₂S/LEL max)
7. Photos / Short Video
-
Choke position indicators, sight glasses, iced sensing lines, VSD fault screen, valve handle positions
8. Well schematic & set points (attach existing)
-
Lift design, normal WHP band, normal separator set points, MAOP of flowlines
9. Permit / Compliance flags
-
Any flare volumes overnight, truck water hauls off-schedule, SPCC-relevant releases
Nuance: Send CSV/historian export + one PDF summary. Engineers lose hours when Ops only sends a screenshot of yesterday’s allocation email.
Tiered Escalation (Ops → Engineering → TOC)
| Level | Objective | Triggers (examples) | Ops actions | Escalate when |
|---|
| 0 | Detect | SCADA rate < 85% of 7-day avg for > 4 h; alarm flood | Confirm data, safety sweep | Always move to 1 within 1 h if real |
| 1 | Local field response | Single well lift trip; dump valve stuck; iced DP lines; choke mis-set | Restore per SOP; methanol; clear faults; re-open SDV if cause known safe | No restore in 2 h OR multi-well OR unknown cause |
| 2 | Supervisory | Pad ≥ 10 to 15% down; sales P ↑ > 50 to 100 psi; separator instability | Midstream call; multi-well balance; put-on-test highest well | Lift redesign needed, integrity issue, or > 18% sustained 8 h |
| 3 | Engineering / TOC | Suspected tubing hole, ESP failure, formation/offset frac hit, chronic takeaway | Deliver full data package; joint decision on pull/slickline/coil | Well control, environmental, or major LOE spend |
| 4 | Emergency | Blowout indicators, fire, major release, H₂S | ESD, evacuation upwind, notify per ERP | N/A: already emergency |
De-escalation: Rates within 5% of baseline stable 6 to 12 h, alarms clear, no integrity flags, documentation filed.
Hazards
-
Well control / unexpected pressure on tree or annulus
-
H₂S / hydrocarbon release while breaking meter lines or thief hatches
-
Hydrate ice plug dislodging as projectile / sudden flow
-
ESP stored energy / unexpected start
-
NORM on filters; benzene in condensate samples
-
Vehicle/line-of-fire at pumpjacks
-
Night/winter slips on Ohio locations
-
Incorrect valve lineup causing overpressure of low-MAOP equipment
Controls
-
Engineering: PSHL/PSLL, SDV, ESD, flame arrestors, relief valves per API 521 design basis; meter dual-path where installed
-
Administrative: This protocol; MOC for set-point changes; LOTO on meters/VSD; two-person for breaking containment; Ohio EPA / ODNR reporting thresholds awareness
-
PPE: As listed
-
Mitigations: Live gas monitoring; stop-work authority; do not bypass safety PLCs without written authorization
ROI Nuance: A disciplined 90-minute Ops diagnostic typically costs a few labor hours. Unnecessary ESP pull or engineering fire drill on a frozen DP cell can run $50k to $250k+ and days of deferred production. At pad rates common in Ohio liquids-rich gas, 18% down on a 50 to 100 MMscfd-equivalent pad is material overnight revenue: speed with data quality matters.
Field-Ready Quick Checklist (Print / Tablet)
First 30 minutes
-
Safety gas check / visual leak
-
Confirm 18% real: by well, by phase
-
SCADA freeze + 72 h export started
-
Sales line pressure vs. normal
-
Separator levels, dumps, PCV mode
-
Top 3 wells: choke, SDV, WHP/CHP
First 60 to 90 minutes
-
Meter DP lines / Coriolis health
-
Lift: ESP faults / GL injection / rod cards / plunger arrivals
-
Tanks / LACT / SWD constraints
-
Midstream suction status
-
Methanol / heat / chemical pumps
-
Narrative + photos
Before engineering call
-
Data package complete (Section Phase 6)
-
What you already tried and result
-
Clear ask: “Need review of X well ESP curve” vs. “Pad down, unknown”
Worked Example Logic (How to Think on Location)
Assume Pad 7 yesterday: 12.0 MMscfd + 1,200 bbl condensate. Overnight: 9.8 MMscfd + 990 bbl (~18% BOE).
-
If sales pressure +80 psi and all WHP ↑ → midstream/takeaway or pad PCV first.
-
If sales pressure flat, Well 3 ESP undervoltage at 02:14 and Well 3 was 20% of pad → lift on Well 3 first.
-
If volumes down but tank straps match yesterday → meter/allocation fault.
-
If gas down, oil flat, separator oil level high → gas meter or foam/level control.
-
If only water rate “down” and oil up slightly → interface/brine dump stuck (allocation optics).
Always reconcile energy balance: reservoir + lift + surface + takeaway + measurement. The broken link is almost never “all five at once.”
References
-
OSHA 29 CFR 1910.119 (PSM where applicable), 1910.146, 1910.147 (LOTO), 1910.1000 (air contaminants)
-
API RP 54 (fire protection / operations safety), API RP 500/505 (classified areas), API RP 11S series (ESP), API RP 11V (gas lift), API 521 (pressure-relieving)
-
API MPMS (metering / proving practices)
-
Ohio Department of Natural Resources (ODNR) Division of Oil & Gas resources management rules; Ohio EPA air/SPCC as applicable
-
Company SEMS / operating procedures; manufacturer VSD/ESP fault guides
-
PHMSA / midstream interconnect operating agreements (takeaway pressure)
Mission locked in. Run the ladder in order:
safetyverify the numberpressuresseparatortakeaway/metersliftthen engineering with a full data pack
That sequence finds the majority of “mystery” 15 to 20% overnight drops without waking the wrong people or pulling the wrong pump.