Click here to open or download the Technical Review Summary
Through late 2018 and early 2019 EPA concurrently released the Subtask F/G Memos (Summary of Empirical Modeling & Nitrogen Endpoints) for public review and commissioned an independent technical review of the Subtask E (Summary of Hydrodynamic Modeling) and F/G Memos. For the Technical Review EPA’s external reviewers considered 15 specific questions, while also keeping in mind EPA’s objective for the review (to ensure scientifically-sound methodologies consistent with professional and relevant scientific practices). The external expert reviewers provided a variety of comments and questions on the analysis, as well as suggestions to improve its scientific defensibility. While supportive of the multiple lines of evidence approach, the reviewers also provided general and specific suggestions that fit within the following three categories:
General Approach for Incorporating the Comments EPA will review the comments from both the public review and the technical review in detail and determine how best to incorporate them into the analyses, given available resources. Below is the general approach the team will use:
Elaborate on the assumption of conservative TN behavior for this analysis.
Add more detail on the stressor-response methods.
Test a larger temporal period to examine the effect of the temporal scale used (i.e., July through September) on area of influence.
Look into additional confounding factors to determine the influence of confounding factors on some models.
As of October 2020 the analysis has been revised based on the public comments and the technical review recommendations. EPA will remain engaged with our partners and the public throughout this process. Additionally, the team will develop a response to all the comments, which will be made available with the revised documents once it has been completed.