Welcome to O2S,i

Obsidian Onsite Services, inc (O2S,i) provides design, construction and maintenance to the residential onsite industry.  I began building my own control panels in 2011 and developed a design for a robust ultraviolet sterilizer* in 2012.  I believe in quality and fair pricing – recognizing that pricing includes the initial cost plus the long term cost of operation and maintenance.

I hope that you’ll take the time to explore this site and review our products.  Feel free to call, or send me an email.  I’m always grateful for feedback.

Joel S. Pinnix, PE

*Patent Pending

Joel's Portrait - BW Joel S. Pinnix, PE

North Carolina State University, 1983
Licensed Engineer in Virginia & North Carolina
Licensed Alternative Operator in Virginia
Licensed Class B Contractor
Licensed Alternative Installer

Providing Onsite Design & Maintenance since 2002

Control Panels


As a practicing engineer, contractor and onsite maintenance provider, I never quite found the control panels that combined the features I wanted with the simplicity I needed – so I built my own.  My control panels follow the age old engineering adage – Keep It Simple.

No Greenboards.  No Logic Programmers.  No Redundant Switches.

If you need a robust panel at a reasonable price, look no further.


Ultraviolet Sterilizer

O2Si Sterilizer Sketch

My patent pending UV sterilizer can be used in both gravity and pressure dosing.  I’ve developed a custom tool for accessing the light in deep burial applications.  I routinely use this sterilizer in my low pressure distribution (LPD) and drip dispersal systems – when the pump is actuated, the bulb is energized.  No wasted electricity and the bulb life is extended reducing long-term costs.

Some of the advantages of the O2S,i UV Sterilizer are:

  • Can be used in Pressure Dosing (Pump Actuated) or Gravity (Continuous On)
  • Pump Actuated service reduces energy costs and increases bulb service life
  • Rebuild cost is only $135 – Bulb ($50) and Transformer ($85)
  • UV Sterilizer Rated at 30,000 µw/cm2 @ 20 gallons per minute (BOD/TSS max 30mg/l)
  • Robust housing allows direct burial and protection from physical and environmental elements
  • Circuit alarm can be connected to any control panel and actuates on circuit fault (such as bulb failure).