Featured Project: Zero-Odor Degassing of 200-ft Sour Crude Sludge Tank – Martinez, California (Carquinez Bridge)
A major Martinez terminal needed to remove several feet of H₂S-rich sludge from a >200-ft diameter sour crude tank and centrifuge it directly adjacent to the Carquinez Bridge toll plaza (I-80, >40,000 vehicles/day).
BAAQMD and Contra Costa County Health Services warned that any detectable odor at the toll booths would trigger a $5-per-car penalty — up to $200,000 per day in fines.
Envent delivered absolute zero odor under a full BAAQMD permit and finished without a single complaint.
The Challenge
- Heavy H₂S/mercaptan sludge in 200+ ft tank
- Centrifuge and temp tanks within 300 ft of toll booths
- 40,000 cars/day = $200,000 daily fine risk
- Must comply with BAAQMD Regulation 8, Rule 2 and Contra Costa County Odor Ordinance
- Fixed-roof tank with manways open during sludge removal
Envent’s BAAQMD-Permitted 3-Phase Zero-Odor Solution
| Phase | Equipment & Internal Link | Purpose |
|---|---|---|
| Phase 1 – Initial Tank Degassing | Recirculating H₂S Scrubber + High-Flow EMTOS Thermal Oxidizer | Bulk H₂S removal & VOC destruction during roof landing |
| Phase 2 – Centrifuge & Temp Tanks | Redundant Liquid/Carbon/Blower Hybrid manifolded to all vessels | 100% capture of centrifuge off-gas & hooch vapors |
| Phase 3 – Open-Manway Sludge Removal | 5,000 CFM blower + 5,000 CFM High-Flow Carbon Trailer under vacuum | Negative pressure on tank with manways open |
Execution Highlights
- Fully permitted under BAAQMD Permit-to-Operate
- Real-time H₂S & odor monitoring at toll booths and fence line
- 24/7 Envent operators with full redundancy
Proven Results – Zero Odor, Zero Fines
| Benefit | Delivered Outcome |
|---|---|
| Odor Control | Zero detectable odor at toll booths or bridge |
| Regulatory Compliance | 100% BAAQMD & Contra Costa County compliant, zero fines |
| Safety | No H₂S exposure, zero incidents |
| Project Duration | Completed on schedule with manways open |
| Cost Avoidance | Saved millions in potential daily penalties |
This project remains the gold standard for high-visibility, high-penalty tank work in the Bay Area.
Got a tank next to clean near homes, bridges, or schools in BAAQMD or Contra Costa County? Get your Free BAAQMD-Permitted Zero-Odor Plan & Quote today. Call Envent’s Bay Area Team at 888-997-9465 or email [email protected] — we make $200,000/day problems disappear.
