Laboratory Assistant - Wet Chemistry

About Us

At Onterris, we build careers grounded in purpose, responsibility and real-world impact.

“For Planet and Progress” is our north star that guides everything we do. We believe environmental responsibility and human progress are interconnected, interwoven and international. Our scientists, engineers, field teams, consultants and professionals collaborate across disciplines and geographies, guiding industries and governments, ensuring that communities and environments thrive.

When you join us, you’re not just forging a career, you’re joining a movement. A movement for better thinking, smarter solutions and lasting impact.

Together, we will advance our way of life and protect the integrity of our environment every step of the way.

As a Full-Time Laboratory Assistant based in our Orange, CA Laboratory
, you’ll step into the lab where every detail matters. You'll play a key role in prepping and handling samples, keeping records accurate, and maintaining a clean laboratory to support on-time results everyday. You’ll collaborate with a strong team of committed professionals, contribute to meaningful scientific work, and grow your expertise in a dynamic, quality-driven environment.

The compensation range for this role is $17.25 to $20 per hour, commensurate with experience, skills, and geographic location.

Department: Wet Chemistry

Schedule: Full-Time. Tuesday - Saturday, 7:30 AM - 4:00 PM

To thrive in this role in the Wet Chemistry Department, you’ll be comfortable taking ownership of the following responsibilities:

• Retrieve, receive, label, store, and dispose of samples in accordance with SOPs, QA requirements, and safety procedures
• Perform basic sample preparation for soil, water, and air samples under supervision
• Prepare reagents and solutions following approved written procedures
• Perform gravimetric and titrimetric measurements as trained
• Assist with filtration, aliquoting, weighing, and other defined preparation steps
• Maintain cleanliness and organization of laboratory work areas, glassware, and storage locations
• Restock consumables, chemicals, and supplies and notify supervisors of low inventory
• Support proper sample storage, refrigerator/freezer organization, and waste handling
• Wear required PPE at all times and report unsafe conditions or spills immediately
• Comply with Onterris Quality Assurance Program and other policies
• Comply with Onterris Health and Safety Plan
• Other duties as assigned by the Group Leader, Operations Manager, or Lab Director

These requirements reflect the knowledge, skills and abilities that help you do your best work here.

• High School diploma or equivalent required
• Ability to follow written procedures and instructions
• Basic understanding of laboratory safety practices

• Prior laboratory, sample-handling, or wet chemistry experience
• Strong attention to detail and organizational skills
• Ability to work effectively under supervision in a team-based environment
• Willingness to learn laboratory procedures and workflows

The physical and environmental requirements below reflect what’s typically needed to perform the essential functions of this role safely and effectively. We may provide reasonable accommodations to qualified individuals with disabilities, consistent with applicable law, to support performance of the essential functions.

• Works in a laboratory and/or office environment
• Sitting, standing, and walking
• Must be able to work in a stationary position for entire shift duration
• Lifting and moving up to 25 lbs independently and 50 lbs using assisted lifting equipment
• Must be comfortable working with strong acids and solvents

Onterris is a leading global environmental solutions company partnering with organizations to solve complex challenges where environmental pressures, regulatory expectations and operational risks intersect. Guided by our mission to advance the way of life without compromising the integrity of our environment, we believe environmental responsibility and human progress are fundamentally connected. Our scientists, engineers, field teams and consultants apply systems thinking that unites science, data and practical expertise to deliver solutions that strengthen our clients’ resilience, mitigate risk and protect the air, water and soil that sustain communities, while uncovering responsible paths forward for planet and progress.

For more information, visit

We are an equal opportunity employer and encourage applications from people of all backgrounds. We acknowledge that these experiences and perspectives help to enrich our teams and contribute to our ongoing success. We are committed to providing access and reasonable accommodation in our employment for all applicants. For US residents,  to learn more.