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Principal Tunnel Engineer



San Francisco, CA, USA
Posted on Tuesday, February 1, 2022

Our Mission

Petra's mission is to protect communities by moving utilities underground. The company is developing technology to efficiently and safely bore utility tunnels through any geology. Petra has developed a hard rock microtunneling solution that is less expensive and more reliable than conventional methods, making small-diameter utility undergrounding through bedrock economically viable.

The Role

The Tunnel Engineer will be lead engineer responsible for all tunnel engineering efforts at Petra. This will be a versatile role, with the tunnel engineer undertaking a cross-section of projects; including: tunnels, caverns, shafts, micro-tunnels, trenchless and other underground structures. The Tunnel Engineer may interface with external firms and vendors as needed, but will be ultimately responsible for the safe and robust design of all of our tunnels.

About you

You are a self-starter and can tackle challenges in a fast paced, high aptitude, technical working environment. You are enthusiastic about showing your work and collaborating with fellow team members. You are able to adapt and develop quick solutions when one is not readily available. You have led engineering efforts on a number of successful projects and take great responsibility in the work you do, designing extremely robust and reliable tunnels built to last.


  • Planning and design of tunnel, micro-tunnel and trenchless projects including initial and final support, excavation support systems, foundations, as well as other underground structures predominately for transit, highway and water projects
  • Assist preparing and monitoring work plans, scope, schedule, and budgets
  • Assist with project pursuits and proposals
  • Work in project teams for the delivery, design, and documentation of project requirements for large transit, highway, water and wastewater tunnels;
  • Exploration methods (soil and rock borings, test pits, CPT probes, seismic geophysical testing), geotechnical instrumentation and monitoring, and laboratory testing for soil (classification, strength, and consolidation) and rock;
  • Inspection of tunneling and trenchless works, shafts and deep excavations;
  • Analysis of laboratory testing results and determination of geotechnical design parameters.
  • Design of earth and rock retaining structures, ground improvement, embankment and cut slopes, tunneling and ground support methods, and both soft and hard rock tunnels and shafts;
  • Preparation of technical reports, data reports, and baseline reports
  • Computer programs including SETTLE3D, SLIDE or SLOPE, SHAFT, DRIVEN, MATHCAD, FB-Multipier, PLAXIS, and FLAC; and
  • Preparation of design drawings and specifications.


  • Bachelor’s or Master’s Degree in Civil / Structural, Geological or Geotechnical Engineering from an accredited university
  • Professional engineering designation or credentials for registration as a professional engineer
  • 10 or more years of experience in microtunneling, tunneling or structural/geotechnical engineering design and investigation for tunnels, caverns, shafts, deep braced excavations and other underground structures/projects
  • Experience with the construction or construction management of tunneling or structural projects a plus
  • Experience in leading the development of plans and specifications for small projects (<$10M construction value) and lead design studies and analyses for larger projects (>$200 M construction value)
  • Experience in writing and reviewing geotechnical reports, including geotechnical baseline reports.
  • Experience in writing technical specifications.
  • Experience working in a consulting engineering environment.
  • Excellent verbal, written and communication skills.
  • Excellent analytical, problem-solving and decision-making skills.
  • Excellent interpersonal and teamwork skills in complex and changing environments.
  • Knowledge and experience with soil and rock mechanics, ground/structural numerical methods and their application in surface and underground environments;
  • Experience with the design of tunnel and shaft support systems/techniques in both soil and rock environments.


  • Competitive salary and equity.
  • 401K plan.
  • Employer-sponsored health, dental and vision insurance.
  • Healthy lunch and snacks provided.
  • Monthly cell phone reimbursement.
  • Paid holidays and flexible PTO.
  • Relocation costs negotiable.

Equal Opportunity Employer

Petra is an Equal Opportunity Employer; employment with Petra is governed on the basis of merit, competence and qualifications and will not be influenced in any manner by race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability or any other legally protected status.