Septic installation and excavation in Auburn, WA,built to code and built to last.
A family-owned crew installing new and replacement septic systems, camera-inspecting the lines you already have, and handling the digging, clearing and drainage around them.
Septic is our main focus. The dirt work around it is too.
One crew, one phone number, from site evaluation to final grade.
Septic installation
New systems for new homes and replacements for failing ones, from site evaluation and permitting to the last riser lid.
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Septic camera inspection
A camera down the line shows blockages, cracks and root intrusion before anyone starts digging.
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Excavation & site work
Clearing, grading, trenching, utility and foundation digging, site drainage, gravel drives and dump truck hauling.
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From permit to backfill, one crew on your septic job
Whether you’re building a new home or replacing an outdated system, we take the job from site evaluation and permitting through installation, working alongside local septic designers.
- Concrete tanks set by crane truck and plumbed to the house
- Gravel and pressure-distribution drainfields, laterals and inspection ports
- Pump vaults and risers brought to grade so the system can be serviced
- Built to code and built to last
From brush to a gravel pad
Clearing, grading and rock, from Lone Mountain’s land-clearing photos.
Our work’s underground. Here’s what it looks like before it’s buried.
Small, family-owned, and staying that way
Lone Mountain Construction is a family-owned business specializing in septic system installation, serving our community since 2023. Septic work is our main focus, and we also offer general excavation, camera inspections and dump truck services.
We’re a licensed, bonded and insured Washington general contractor. You can check our license with L&I any time: #LONEMMC762DG.
Rated 5.0 on Google. More of our work is on Facebook.