3 
• Chapter 7 documents new recommended methodologies and procedures for 
using shallow-water monitoring data in assessing attainment of Chesapeake 
Bay water quality criteria and tidal water designated uses. 
• Chapter 8 documents a recommended 303(d) list decision-making framework 
for assessment of Chesapeake Bay and its tidal tributaries and embayments. 
This document represents the second formal addendum to the 2003 Chesapeake Bay 
water quality criteria document; as such, readers should regard the sections in this 
document as new or replacement chapters and appendices to the original published 
report. The criteria attainment assessment procedures published in this addendum 
replace and otherwise supercede similar criteria assessment procedures originally 
published in the 2003 Regional Criteria Guidance and 2004 addendum (U.S. EPA 
2003, 2004). Publication of future addendums by EPA on behalf of the Chesapeake 
Bay Program watershed jurisdictional partners is likely as continued scientific 
research and management applications reveal new insights and knowledge that 
should be incorporated into revisions of state water quality standards regulations in 
upcoming triennial reviews. 
LITERATURE CITED 
U.S. Environmental Protection Agency. 2003. Ambient Water Quality Criteria for Dissolved 
Oxygen, Water Clarity and Chlorophyll a for Chesapeake Bay and Its Tidal Tributaries. EPA 
903-R-03-002. Region III Chesapeake Bay Program Office, Annapolis, MD. 
U.S. Environmental Protection Agency. 2004. Ambient Water Quality Criteria for Dissolved 
Oxygen, Water Clarity and Chlorophyll a for Chesapeake Bay and Its Tidal Tributaries - 
2004 Addendum. EPA 903-R-04-005. Region III Chesapeake Bay Program Office, 
Annapolis. MD. 
chapter i 
Introduction 
