Receiving Water Body:

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1 ENVIRONMENTAL RESOURCE PERMIT INDIVIDUAL - TECHNICAL STAFF REPORT 04-Nov-2015 APPLICATION #: IND Applicant: Eddie Dixon Holmes District School Board 701 E Pennsylvania Ave Bonifay, FL (850) Project Name: Holmes County K-8 School Acres Owned: Project Acreage: County: Holmes STR: Section(s): Township(s): Range(s): 1 4N 15W Receiving Water Body: Name Choctawhatchee River Class III Fresh, OFW Authority (2)(c), (2)(d), (2)(b) Final O&M Entity: Holmes District School Board ERP Conservation Easements/Restrictions: No Interested Parties: No Objectors: No Authorization Statement: Construction of a stormwater management system for the proposed Holmes County K-8 School, a acre project to be constructed as per revised plans received by the District on October 21, The stormwater management system will utilize dry retention for the northeast pond and dry detention with filtration using above grade vertical sand filters for the south and north ponds, each pond serving an hydraulically separate stormwater drainage area. Recommendation: Approval Reviewers: Ken Greenwood; Ron Potts Engineering Comments: The project is construction of an elementary and middle school complex on the location of the former Holmes County fairgrounds. The project area is acres and the site is adjacent to the existing Holmes County High School. The new construction project will consist of a classroom building, paved driveways and parking areas, playgrounds, a

2 small pump house to boost water pressure for the for the complex s water system, and a stormwater system using three dry ponds. Rate control is not required due the project area having less than 12 acres total impervious and having less than 50 percent impervious surface over the project area. There are a total of three stormwater ponds serving the project area. The proposed surface water management system has been designed as one dry retention pond system in the northeast corner of the project, and two dry detention ponds with each having three above grade in-pond vertical sand filters. The stormwater pond bottom elevations are designed above the seasonal high ground water table. A geotechnical investigation revealed native soil infiltration rates that were unsuitable for the two ponds in the western part of the project area, therefore they were designed with the vertical sand filters to achieve the necessary treatment volume drawdown within the required time and using a safety factor of 2.0. The two filter ponds, South and North, require 23,567 and 20,512 cubic feet of treatment volume and have 24,071 and 22,924 cubic feet, respectively, both exceeding the required volumes. The treatment volume has been designed to recover in each pond in 33 and 30.3 hours, respectively. The retention pond (Northeast) is designed to have the required volume of 24,119 cubic feet and to recover the treatment volume in 23.5 hours. Environmental Comments: Project will include filling a 0.63 acre man-made impoundment. No natural wetlands will be affected by the project. Site Description:The project site is located entirely in an upland area that is open, covered with grasses and herbaceous plants, and periodically maintained by mowing. The upland area slopes gradually off to the west, where it is wooded, a bit more steeply sloped and transitions into a wetland area bordering the west side of the property. A small asphalt paved parking lot and the foundation and concrete block walls of two former buildings are located in the south portion of the project area. Three or four shallow and dry stormwater ponds which appear to have been constructed many years ago are located along the edge of the wooded area on the west side of the upland. One pond containing water is located in the north part of the project area. Conditions 1. All activities shall be implemented following the plans, specifications and performance criteria approved by this permit. Any deviations must be authorized in a permit modification in accordance with Rule , F.A.C. Any deviations that are not so authorized may subject the permittee to enforcement action and revocation of the permit under Chapter 373, F.S. 2. A complete copy of this permit shall be kept at the work site of the permitted activity during the construction phase, and shall be available for review at the work site upon request by the Agency staff. The permittee shall require the contractor to review the complete permit prior to beginning construction. 3. Activities shall be conducted in a manner that does not cause or contribute to violations of state water quality standards. Performance-based erosion and sediment control best management practices shall be installed immediately prior to, and be maintained during and after construction as needed, to prevent adverse impacts to the water resources and adjacent lands. Such practices shall be in accordance with the State of Florida Erosion and Sediment Control

3 Designer and Reviewer Manual (Florida Department of Environmental Protection and Florida Department of Transportation June 2007), and the Florida Stormwater Erosion and Sedimentation Control Inspector s Manual (Florida Department of Environmental Protection, Nonpoint Source Management Section, Tallahassee, Florida, July 2008), which are both incorporated by reference in subparagraph (9)(b)5., F.A.C., unless a project-specific erosion and sediment control plan is approved or other water quality control measures are required as part of the permit. 4. At least 48 hours prior to beginning the authorized activities, the permittee shall submit to the Agency a fully executed Form (1), Construction Commencement Notice, [October 1, 2013], incorporated by reference herein ( indicating the expected start and completion dates.a copy of this form may be obtained from the Agency, as described in subsection (5), F.A.C. If available, an Agency website that fulfills this notification requirement may be used in lieu of the form. 5. Unless the permit is transferred under Rule , F.A.C., or transferred to an operating entity under Rule , F.A.C., the permittee is liable to comply with the plans, terms and conditions of the permit for the life of the project or activity. 6. Within 30 days after completing construction of the entire project, or any independent portion of the project, the permittee shall provide the following to the Agency, as applicable: 1. For an individual, private single-family residential dwelling unit, duplex, triplex, or quadruplex Construction Completion and Inspection Certification for Activities Associated With a Private Single-Family Dwelling Unit [Form (3)]; or 2. For all other activities As-Built Certification and Request for Conversion to Operational Phase [Form (1)]. 3. If available, an Agency website that fulfills this certification requirement may be used in lieu of the form. 7. If the final operation and maintenance entity is a third party: 1. Prior to sales of any lot or unit served by the activity and within one year of permit issuance, or within 30 days of as- built certification, whichever comes first, the permittee shall submit, as applicable, a copy of the operation and maintenance documents (see sections 12.3 thru of Volume I) as filed with the Department of State, Division of Corporations and a copy of any easement, plat, or deed restriction needed to operate or maintain the project, as recorded with the Clerk of the Court in the County in which the activity is located. 2. Within 30 days of submittal of the as- built certification, the permittee shall submit Request for Transfer of Environmental Resource Permit to the Perpetual Operation Entity [Form (2)] to transfer the permit to the operation and maintenance entity, along with the documentation requested in the form. If available, an Agency website that fulfills this transfer requirement may be used in lieu of the form.

4 8. The permittee shall notify the Agency in writing of changes required by any other regulatory agency that require changes to the permitted activity, and any required modification of this permit must be obtained prior to implementing the changes. 9. This permit does not: 1. Convey to the permittee any property rights or privileges, or any other rights or privileges other than those specified herein or in Chapter , F.A.C.; 2. Convey to the permittee or create in the permittee any interest in real property; 3. Relieve the permittee from the need to obtain and comply with any other required federal, state, and local authorization, law, rule, or ordinance; or 4. Authorize any entrance upon or work on property that is not owned, held in easement, or controlled by the permittee 10.The permittee shall hold and save the Agency harmless from any and all damages, claims, or liabilities that may arise by reason of the construction, alteration, operation, maintenance, removal, abandonment or use of any project authorized by the permit. 11. The permittee shall notify the Agency in writing: 1. Immediately if any previously submitted information is discovered to be inaccurate; and 2. Within 30 days of any conveyance or division of ownership or control of the property or the system, other than conveyance via a long-term lease, and the new owner shall request transfer of the permit in accordance with Rule , F.A.C. This does not apply to the sale of lots or units in residential or commercial subdivisions or condominiums where the stormwater management system has been completed and converted to the operation phase 12.Upon reasonable notice to the permittee, Agency staff with proper identification shall have permission to enter, inspect, sample and test the project or activities to ensure conformity with the plans and specifications authorized in the permit. 13.If any prehistoric or historic artifacts, such as pottery or ceramics, stone tools or metal implements, dugout canoes, or any other physical remains that could be associated with Native American cultures, or early colonial or American settlement are encountered at any time within the project site area, work involving subsurface disturbance in the immediate vicinity of such discoveries shall cease. The permittee or other designee shall contact the Florida Department of State, Division of Historical Resources, Compliance and Review Section, at (850) or (800) , as well as the appropriate permitting agency office. Such subsurface work shall not resume without verbal or written authorization from the Division of Historical Resources. If unmarked human remains are encountered, all work shall stop immediately and notification shall be provided in accordance with Section , F.S.

5 14.Any delineation of the extent of a wetland or other surface water submitted as part of the permit application, including plans or other supporting documentation, shall not be considered binding unless a specific condition of this permit or a formal determination under Rule , F.A.C., provides otherwise. 15.The permittee shall provide routine maintenance of all components of the stormwater management system to remove trapped sediments and debris. Removed materials shall be disposed of in a landfill or other uplands in a manner that does not require a permit under Chapter , F.A.C., or cause violations of state water quality standards. 16.This permit is issued based on the applicant s submitted information that reasonably demonstrates that adverse water resource-related impacts will not be caused by the completed permit activity. If any adverse impacts result, the Agency will require the permittee to eliminate the cause, obtain any necessary permit modification, and take any necessary corrective actions to resolve the adverse impacts. 17.A Recorded Notice of Environmental Resource Permit may be recorded in the county public records in accordance with subsection (7), F.A.C. Such notice is not an encumbrance upon the property. 18.If during construction or operation of the stormwater management system, a structural failure is observed that has the potential to cause the direct discharge of surface water into the Floridan Aquifer System, corrective actions designed or approved by a registered professional shall be taken as soon as practical to correct the failure. A report prepared by a registered professional must be provided as soon as practical to the District for review and approval that provides reasonable assurance that the breach will be permanently corrected. 19.If unanticipated limestone formations are encountered during construction of the retention basins, or a sinkhole or solution cavity forms during construction, construction of the basin must be halted immediately and the District must be notified. Remedial action may be required. 20.Grassed areas of the retention system shall be fertilized only as needed to maintain vegetation, and shall be mowed regularly in order to be kept at a manageable length as required for system functionality, maintenance, and safety. 21.Percolation performance shall be evaluated within the pond at least every third year. If there is evidence of inadequate percolation, the pond bottom must be rescarified or deep-raked to restore percolation characteristics. If reworking the pond bottom fails to restore adequate percolation, additional retention area restoration shall be performed as follows: a. Remove the top layer of the retention area bottom material to a depth of 2 to 3 inches and scarify or deep-rake the excavated bottom. b. Replace excavated bottom material with suitably permeable material and restore the pond bottom to design grade.

6 22.Grassed areas of the stormwater system shall be mowed regularly in order to be kept at a manageable length as required for system functionality, maintenance, and safety. 23. Inspections by the Permittee o The stormwater system shall be inspected periodically for accumulation of debris and trash. Accumulations of debris and trash that negatively affect the function of the system shall be removed upon discovery. o The stormwater system bottom shall be periodically inspected for silt accumulation. Significant accumulations of silt that negatively affect the function of the system shall be removed. o The permittee shall perform annual field inspections of each filtration basin. 24.In addition to these conditions, the Permittee shall comply with all maintenance and inspection requirements prescribed in the Maintenance Plan developed by the Registered Professional who designed the system. 25. Inspections by a Registered Professional. The stormwater management system shall be inspected by a registered professional to evaluate whether the system is functioning as designed and permitted. The Registered Professional may record his inspection on Form No (1), Operation and Maintenance Inspection Certification or may provide his evaluation in any other format; however any report must be signed and sealed by the Registered Professional. Submittal of the inspection report to the District is not required; but the report shall be made available to the District upon request. Inspections shall be made by the Registered Professional in accordance with this schedule: o On the first anniversary of the date of conversion to Operation and Maintenance Phase. o Every second year on the anniversary of conversion to Operation and Maintenance phase, after the first year of successful operation. 26. Reporting by a Registered Professional Within 30 days of any failure of a stormwater management system or deviation from the permit, a report shall be submitted to the District on Form (1), Operation and Maintenance Inspection Certification, describing the remedial actions taken to resolve the failure or deviation. This report shall be signed and sealed by a Registered Professional.