Greenhouse Gas Emissions: Site Selection and Measurement: PRESENTATION ONLY
Kenneth McGibbon, Technical Director, Mott MacDonald
(Free)
Risk based site selection
Risk factors selected based on ‘available data’ for many sites
Identified Risk Factors and Assigned Significance:
Highly significant (Weighting = 3)
• High FE nitrite (L<0.5 mg/l, H>1.5 mg/l)
• High sludge age (carbonaceous ASPs only) (L<5, H>10 days)
• Ammonia failure status (L = No, H = Yes)
Very significant (Weighting = 2)
- Capacity utilisation % (L<80%, H>110%)
- Low ammonia consent (L>16mg/l, H<5 mg/l)
- Absolute difference of influent and consent ammonia (L<5mg/l, H>15mg/l)
- Ratio of 95%ile : average effluent ammonia (L<1.5, H>3.5)
Significant (Weighting = 1)
• BOD failure status (L = No, H = Yes)
• Low BOD consent (L>25 mg/l, H<15 mg/l)
• Presence of STC liquor returns and / or AD(0 = WWTWL= Non-AD STCM = Digestion indigenous only H = Digestion with imports)