Engineering Distribution interview prep.

Behavioural questions to expect

1. Walk me through your background + gas distribution engineering experience.
2. Tell me about a gas distribution project you've led.
3. Why gas distribution engineering vs midstream pipeline, electric distribution, or LNG engineering?
4. Why this discipline - distribution planning, design, DIMP / system integrity, cathodic protection, pressure regulation?
5. Why the firm?
6. What's your read on our distribution capital plan + recent rate case?
7. Tell me what you understand about our safety + DIMP posture.
8. Walk me through a gas distribution planning or pressure study you've done.

Technical concepts to master

• Gas distribution planning + design

  Degree-day load forecast · Main + service sizing + pressure regulation · MAOP + class location · Pressure tiers + system architecture · EFVs (Excess Flow Valves)

• DIMP - Distribution Integrity Management Program (Subpart P)

  Seven required DIMP elements · Seven threat categories · Additional + accelerated actions · Performance measures · Mechanical fittings + repair

• Cathodic protection + plastic pipe

  Cathodic protection criteria · Casing isolation + shorted casings · Plastic pipe materials + fusion · Tracer wire + locating · Cast iron + bare steel legacy

• Damage prevention + methane emissions

  811 + one-call + RP 1162 · Public awareness program · Methane emissions + LAUF · Methane Emissions Reduction Program (MERP) · Advanced leak detection

Practical drills

• A 4-inch MDPE main at 60 psig serves a growing suburb with 1,800 customers; design-day peak is 4,200 SCFH and forecast grows 4% per year with a 600 SCFH commercial customer coming online in year 2. The downstream district regulator sees pressure dropping below 35 psig minimum at peak. Walk through your planning study + options.
• A DIMP segment review shows third-party damage rate has risen from 2.1 to 3.4 per 1,000 tickets over two years on a 38-mile cast iron + bare steel sub-system in a dense urban corridor. Walk through your DIMP additional + accelerated actions plan.
• A customer reports gas odour outside their home at 9pm. Bar-hole readings show 4% gas-in-air (above 1% LEL bar-hole threshold) at the curb above a coated steel main with 30-year-old service tee. Walk through your immediate + 48-hour response.

Smart-question anchors

• Distribution capital plan - accelerated cast iron / bare steel replacement + signature programmes
• DIMP + safety posture - Grade 1 / 2 / 3 leak trend + third-party damage rate + performance measures
• Methane + emissions posture - LAUF trend + MERP exposure + advanced leak detection deployment
• Damage prevention - 811 / locate performance + public awareness program
• Engineering org + tool stack - Synergi Gas / SynerGEE / Stoner SPS + GIS + planning / design / DIMP / CP groups

Sourced from

49 CFR Part 192 (PHMSA Gas Pipeline Safety) + Subpart P (DIMP) + Subpart I (Corrosion) · GPTC Z380.1 (Gas Piping Technology Committee Guide) + ASME B31.8 / B31.8S · API RP 1162 Public Awareness + ASTM F2620 fusion + NACE SP0169 cathodic protection · EPA Methane Rule + Subpart W GHGRP + IRA Methane Emissions Reduction Program (MERP) · Pipeline & Gas Journal + AGA + APGA + state PUC distribution dockets + PHMSA Distribution Annual Reports