Environmental Engineering Expert

---
name: environmental-engineering-expert
version: 1.0.0
description: Expert-level environmental engineering covering water treatment, wastewater treatment, air quality, solid waste, site remediation, and environmental regulations.
author: luo-kai
tags: [environmental engineering, water treatment, wastewater, air quality, remediation]
---

# Environmental Engineering Expert

## Before Starting
1. Water, air, or soil contamination focus?
2. Treatment design or regulatory compliance?
3. Municipal or industrial application?

## Core Expertise Areas

### Water Treatment
Coagulation and flocculation: destabilize colloids, form settleable floc.
Sedimentation: gravity settling of floc, surface overflow rate determines size.
Filtration: rapid sand filter removes remaining turbidity and pathogens.
Disinfection: chlorine, ozone, or UV to inactivate pathogens.
Membrane treatment: ultrafiltration, nanofiltration, reverse osmosis.

### Wastewater Treatment
Primary: screening, grit removal, primary clarifier removes settleable solids.
Secondary: biological treatment, activated sludge, removes dissolved organics.
Tertiary: nutrient removal, filtration, advanced treatment for reuse.
Biosolids: stabilized sludge for land application or disposal.
BOD and COD: measures of organic pollutant strength in wastewater.

### Air Quality
Criteria pollutants: CO, NOx, SOx, PM2.5, PM10, ozone, lead regulated by EPA.
Dispersion modeling: Gaussian plume model predicts downwind concentrations.
Emission controls: scrubbers for SOx, SCR for NOx, baghouses for particulates.
Indoor air quality: VOCs, radon, CO, biological contaminants.

### Site Remediation
Site characterization: soil and groundwater sampling to define contamination.
Risk assessment: exposure and toxicity to determine cleanup levels.
In-situ treatment: pump and treat, permeable reactive barriers, bioremediation.
Ex-situ treatment: excavation and treatment of contaminated soil.

## Best Practices
- Characterize contamination thoroughly before selecting remediation approach
- Design for peak flows and loads not just average conditions
- Monitor treatment performance continuously and adjust operation
- Engage regulators early in remediation planning process

## Common Pitfalls
| Pitfall | Fix |
|---|---|
| Underdesigning for peak flows | Design for peak hour and peak day flows |
| Ignoring sludge management | Sludge handling is often largest cost in treatment |
| Wrong cleanup standard for site use | Use risk-based cleanup levels appropriate for future land use |
| Missing secondary containment | All chemical storage requires secondary containment |

## Related Skills
- hydraulics-expert
- hydrology-expert
- geotechnical-engineering-expert