Contents 
Acknowledgements. 3 
I. Introduction.5 
Literature cited.6 
II. Designated Use Boundaries: Episodic Pycnocline Application and 
Expanded Designated Uses.8 
Background.8 
Revising a Procedural Anomaly in the Designated Use Delineation.9 
Identification of a Procedural Anomaly.9 
Episodic Pycnocline Criteria Assessment Protocol Modification.10 
Expanded Application of Deep-Water and Deep-Channel Designated Uses.11 
Review of Designated Use Definitions.11 
Mesohaline Segments Expanded Designated Uses.12 
Literature Cited. 14 
III. Biologically-based Reference Curve: Revisions to the Methodology and 
Applications.15 
Background.15 
Issues with Dissolved Oxygen Criteria Assessment with the Available Previously 
Published Biologically-based Reference Curves.16 
Updates to Dissolved Oxygen Biologically-based reference Curve Derivation 
Methodology.17 
Restrict dataset to data collected beginning in 1996. 18 
Use sequential 3-year time periods rather than single years.18 
Screening criteria sample size n>10.19 
Screening criteria standard deviation < 1.0.19 
Definition of healthy benthic macroinvertebrate reference community 
conditions.20 
Use Grand Score in computations involving fixed station data.20 
Summary of Recommendations.21 
Application of a Reference Curve for Open-Water 30-day Mean Dissolved Oxygen 
Criteria: Summer Season.23 
Application of a Reference Curve for Deep-Water Mean Dissolved Oxygen 
Criteria.23 
Application of a Reference Curve for Deep-Channel Instantaneous Minimum 
Dissolved Oxygen Criterion.24 
Comparisons of Degraded Reference Benthic Communities with the Published 
Deep Channel Reference Curve .25 
Rationale for Acceptable Exceedances of the Deep Channel Instantaneous 
Minimum Dissolved Oxygen Criterion.26 
Assessment of Summer Season Dissolved Oxygen Criteria.27 
1 
