Alternative to EPA Method 9 -- Field Validation of the Digital Opacity Compliance System (DOCS)

摘要

The Digital Opacity Compliance System (DOCS) software translates images from a commercial digital camera into visual plume opacity measurements, and is proposed as an alternate reporting method to EPA Method 9. Field tests confirmed that, under fair weather conditions, DOCS consistently met prescribed standards for quantitative accuracy and reliability. At real-world industrial operations, accuracy of DOCS's opacity measurements was comparable to Method-9- certified human observers'. Under dark, overcast skies, both DOCS and human readers were less accurate, but DOCS opacity measurements were less compromised, supporting a claim that DOCS is more reliable than Method 9 for all types of stationary sources and under all weather conditions. DOCS will (1) improve measurement objectivity and reliability, (2) lower deployment and maintenance costs and (3) provide permanent digital images of visible opacity--evidence in regulatory enforcement actions. Economic analysis projects $9,011.82 (stateside) and $15,650.10 (remote facilities) annual savings per pair of trained users. DoD certifies 3,400+ Method 9 readers, so DoD-wide adoption of DOCS could decrease compliance costs $15.3M annually, payback occurring in months. Life-cycle cost analysis projects savings of $40,118.82 (stateside) and $69,671.12 (remote) per pair of users, and aggregate DoD financial benefit of $68.2M (assuming five years useful life). Necessary for implementation is concurrence by regulators, which process is underway.