On June 17th, 2022, the St. Johns River Water Management District, SJRWMD, sent a response to a Request for Additional Information letter for the development of a Wawa restaurant and gas station, with a list of required information before the development can proceed with construction.
Below is the information that was given to the developer that needs to be corrected before the SJRWMD can approve the environmental review, allowing the property owner to begin construction.
- The retention depths provided does not provide sufficient removal efficiency to meet the removal efficiency needed. Please revise accordingly. Please note that the retention depth from the impaired water analysis must be relative to the applicable removal efficiency that show net improvement, where the post-development annualized mass nutrient load discharge from the site is less than the pre-development site loading for nutrient.
- It appears that the rainfall amount used is less than the rainfall amount for the proposed project area. Please review and submit a revised model with the correct amount of rainfall.
- It appears that the runoff coefficient assumed in the pre-development and post-development condition does not represent the mean annual runoff coefficient. Please note that the runoff coefficient utilized in a nutrient analysis is not the coefficients provided in the Applicant’s Handbook.
- Account for the directly connected impervious area in estimating the mean annual runoff volume.
- Please revise the annual mass loading calculations as the number provided is incorrect.
- Demonstrate that the treatment volume required to meet the nutrient removal efficiency is recovered within 72 hours after revising the previous comments.
- The seasonal high groundwater table elevation assumed in the PONDS analysis appears to be inconsistent with the geotechnical report. The seasonal high ground water table for boring samples B6-B8 are 3 feet above measured levels. Based on the existing grades within the footprint of the pond, it appears that the seasonal high groundwater table is higher than assumed.
- Please consider the hardpan layer encountered in Boring B5 in the soil parameters assumed as previously requested.
- It is not clear what is the bottom elevation for the pond where Structure A-3 exist. Please provide grading information for that pond. Additionally, please provide a cross-section for each pond to show if the side slopes are 4:1. Please note that dry basins shall contain side slopes no steeper than 4:1 or shall be fenced or otherwise restricted from public access. Please review and submit revised plans.
The SJRWMD is in charge of reviewing proposed developments and making sure that they meet all state requirements for water safety standards, says the developer has 90 days to complete the requested information and submit it back to the SJRWMD.
You can view the full engineering plans below