A-51 
CFD simulations 
Figure 5.8. Confidence bounds based on quantiles of fraction of space computed on 
conditionally simulated surface estimates using variogram estimates from data. 
The base simulation has spatial and temporal trend estimated from Patuxent data. 
Sample size is 40. 
6.0 FINDINGS —SCIENTIFIC ACCEPTANCE OF CFD 
COMPLIANCE APPROACH 
6.1. CFD APPROACH AS BEST AVAILABLE SCIENCE 
This report represents an initial expert review of the CFD compliance approach. In 
addition the panel undertook simulation tests on the effects of 1) sample densities in 
time and space, 2) varying levels of attainment, and 3) varying degrees of spatial and 
temporal covariance. Further, trials of spatial modeling on fixed station Chesapeake 
Bay water quality data were conducted to begin to evaluate spatial modeling proce¬ 
dures. Based upon review of underlying theory, initial statistical assessments, and 
implementation feasibility, the panel finds that the CFD approach currently repre¬ 
sents best available science in its application to water quality attainment 
appendix a 
The Cumulative Frequency Diagram Method for Deteimining Water Quality Attainment 
