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Delaware General AssemblyDelaware RegulationsMonthly Register of RegulationsFebruary 2019

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7 DE Admin. Code 5101
Under the authority vested in the Secretary of the Department of Natural Resources and Environmental Control (“Department” or “DNREC”), pursuant to 7 Del.C. §§6006 and 6010, and all other relevant statutory authority, the following findings of fact based on the record, reasons and conclusions are entered as an Order of the Secretary in the above-referenced regulatory proceeding.
This Order relates to proposed regulation amendments (“Amendments”) to 7 DE Admin. Code 5101: Delaware Sediment and Stormwater (“Stormwater Regulations”). This action is being taken by the Department to correct previous procedural flaws, as determined by both the Delaware Superior Court and the Delaware Supreme Court, and as set forth in greater detail below. Additionally, numerous other revisions are being proposed at this time to provide additional clarity to the regulated community, and to correct various clerical and consistency errors presently contained therein.
The Department’s Stormwater Regulations were first promulgated in 1991. Under those provisions, all land disturbing activity in an area greater than 5,000 square feet was required to operate under a plan that encompasses both temporary erosion and sediment control during construction, as well as permanent stormwater management controls for both water quantity and water quality. Stormwater management design, at that time, was based upon peak rates of runoff, typically expressed as a quantity per unit of time, such as cubic feet per second.
The Department subsequently amended its Stormwater Regulations in April, 2005 to incorporate the recommendations of the Governor’s Task Force, as noted above, and also to encourage the use of green technology Best Management Practices (“BMPs”), or, those practices that would achieve stormwater management objectives by applying the principles of filtration, infiltration and storage, while minimizing reliance on structural components. These regulations were further amended in October, 2006, by legislative action, to include volume control in stormwater management, as well as the utilization of various methods such as infiltration and recharge, which were feasible for certain watersheds in New Castle County, so as not to increase flood elevations downstream. Volume control was required in these watersheds, to the maximum extent practicable (“MEP”), for all storm events up to the 100-year storm. Additional provisions to these regulations were made, at that time, to ensure that there was not an increase in flood elevations if volume reduction was not feasible.
The Department’s Sediment and Stormwater Program promulgated additional regulatory amendments to its Stormwater Regulations in 2013, which were published in the January 1, 2014 edition of the State of Delaware Register of Regulations. These amendments were largely based upon the previous 2006 revisions, which at that time were expanded by the Department on a state-wide basis. A companion Technical Document (consisting of both the Department’s Erosion and Sediment Control Handbook and BMPs, as referenced above) was also created by the Department. The Department’s 2014 Stormwater Regulations were immediately challenged by the regulated community with an appeal to the Delaware Superior Court, due to the fact that the accompanying Technical Document referenced by those regulations was not published in the State of Delaware Register of Regulations in accordance with the requirements set forth in Delaware’s Administrative Procedures Act (29 Del.C. Ch. 101, Administrative Procedures). A Delaware Superior Court decision of October 7, 2015, which was subsequently upheld by the Supreme Court on April 15, 2016, invalidated the Department’s 2014 Stormwater Regulations on those procedural grounds. The Department immediately enacted Emergency Regulations, by the issuance of Secretary’s Order No. 2016-WS-0019 (April 16, 2015), which incorporated both the 2014 version of the Department’s Stormwater Regulations and the latest version of the aforementioned Technical Document (April 2016) to correct the previous procedural error, and to ensure that Delaware was not without regulations to govern construction activities until such time as the Department was able to formally adopt such finalized regulations.
While the Department was going through the extensive regulatory drafting process via the RAC efforts noted above, several pieces of legislation were also introduced by Delaware’s 148th General Assembly. Due to the fact that Emergency Regulations expire after 180 days, Delaware’s legislature passed legislation to codify certain requirements of the Amendments (which, at that time, were still in the process of being drafted by the Department), and to allow the RAC to continue its work without the constraint of the standard Emergency Regulation time limit.
Of those legislative actions, three were ultimately codified: Senate Bill 253 and House Bill 194 (which both became effective in 2016), and most recently, Senate Bill 204 (which was introduced by Delaware’s 149th General Assembly and became effective in July, 2018). The most significant of these was Senate Bill 253, signed into law by Governor Markell on June 24, 2016. Senate Bill 253 included several stormwater provisions, the most notable of which allowed additional time for the RAC to thoroughly discuss all of the necessary revisions and amendments to the Stormwater Regulations by eliminating the 180 day expiration of the Emergency Regulations. Senate Bill 253 included the following provisions:
Most recently, Senate Bill 204 (signed into law by Governor Carney in July, 2018) incorporated interim standards for redevelopment criteria, which the RAC was in the process of revising, but had not yet formally incorporated into Delaware’s Stormwater Regulations. Of note is the fact that the redevelopment portion of Senate Bill 204 was drafted so as to “sunset” upon the Department’s formal adoption of these proposed Amendments. Additionally, Senate Bill 204 established the criteria for offsets, and formally clarified the procedural status of supporting materials, known as regulatory guidance documents, published by the Department to facilitate compliance with the Stormwater Regulations. Regulatory guidance documents, including the BMP standards and specifications and the Delaware Erosion and Sediment Control Handbook, do not need to go through the Department’s formal regulatory adoption process. The Department is, however, required to provide public notice with regard to any changes to those supporting materials.
The regulatory amendments being proposed at this time by the Department are meant to correct the previous procedural flaw, as determined by both the Delaware Superior Court and the Delaware Supreme Court, by incorporating portions of the Technical Document as part of the actual Stormwater Regulations. Specifically, the Standard Plan section of the Technical Document has now been incorporated into Section 3.7 of the proposed Amendments. Additionally, the regulatory elements of the BMP standards and specifications from the aforementioned Technical Document have now been incorporated into (new) Sections 11 and 12 of the proposed Amendments. Numerous other revisions have been proposed at this time to provide addition clarity to the regulated community and to correct various clerical and consistency errors presently contained therein.
(New) Section 12.0, Supplemental Requirements for Best Management Practices, was added to provide clear requirements for soil investigation procedures and setbacks for stormwater management BMPs;
(New) Section 13.0, Stormwater Management Offsets, was added to take the place of subsection 1.7, and to provide more explanation and clarification with regard to stormwater management offsets, including fees-in-lieu, banking, and stormwater management offset districts; and
Section 5.0, Performance Criteria for Post Construction Stormwater Management, has been updated to address compliance methods updated by Senate Bills 253 and 204.
The Department has the statutory basis and legal authority to act with regard to promulgation of the proposed amendments to 7 DE Admin. Code 5101: Delaware Sediment and Stormwater Regulations, pursuant to 7 Del.C. Ch. 40, Erosion and Sedimentation Control, specifically, Section 4006(c). The Department published its initial proposed regulation Amendments in the September 1, 2018 Delaware Register of Regulations. Thereafter, the public hearing regarding this matter was held on October 10, 2018.
It should be noted that, subsequent to the initial proposed regulatory Amendments having been published in the Delaware Register of Regulations on September 1, 2018, but prior to the public hearing held on October 10, 2018, several revisions were made by the Department in the initial proposed Amendments. The Division of Watershed Stewardship provided handouts for those in attendance at the aforementioned hearing, which charted all of the revisions made to the initial proposed Amendments. Thus, all pre-hearing revisions to the Department’s initial proposed Amendments were fully vetted to the public at the time of the hearing, and no additional re-noticing or re-publication of the same is necessary in this matter.
Hearing Officer Vest subsequently prepared a Hearing Officer’s Report dated January 7, 2019 (“Report”), which expressly incorporated both the Department’s proposed revised Amendments and the aforementioned TRM into the hearing record generated in this matter. The Report documents the proper completion of the required regulatory amendment process, establishes the record, and recommends the adoption of the proposed revised Amendments as attached to the Report as Appendix “A.”
Based on the record developed by the Department’s experts and established by the Hearing Officer’s Report, I find that the proposed revised regulatory amendments to 7 DE Admin. Code 5101: Delaware Sediment and Stormwater Regulations, are well-supported. Therefore, the recommendations of the Hearing Officer are hereby adopted, and I direct that the proposed revised Amendments be promulgated as final. I further find that the Department’s experts in the Division of Watershed Stewardship fully developed the record to support adoption of these revised Amendments.
1. The Department has the statutory basis and legal authority to act with regard to the proposed revised Amendments to 7 DE Admin. Code 5101: Delaware Sediment and Stormwater Regulations, pursuant to 7 Del.C. Ch. 40, Erosion and Sedimentation Control, specifically, Section 4006(c);
2. The Department has jurisdiction under its statutory authority, pursuant to 7 Del.C. Ch. 60, to issue an Order adopting these proposed revised Amendments as final;
3. The Department provided adequate public notice of the initial proposed Amendments and all proceedings in a manner required by the law and regulations, provided the public with an adequate opportunity to comment on the proposed revised Amendments, including at the time of the public hearing held on October 10, 2018, and during the 15 days subsequent to the hearing (through October 25, 2018), before making any final decision;
4. Promulgation of the proposed revised Amendments to 7 DE Admin. Code 5101: Delaware Sediment and Stormwater Regulation, will enable the Department to (1) update Delaware’s Stormwater Regulations to be consistent with recent changes in Delaware law; (2) correct the previous procedural flaw as determined by the Delaware Superior Court and the Delaware Supreme Court, as referenced above, by incorporating the aforementioned portions of the Technical Document as part of the Department’s finalized Stormwater Regulations; and (3) provide additional clarity to the regulated community while correcting various clerical and consistency errors presently contained therein;
5. The Department has reviewed the proposed revised Amendments in the light of the Regulatory Flexibility Act, consistent with 29 Del.C. Ch. 104, and believes the same to be lawful, feasible and desirable, and that the recommendations as proposed should be applicable to all Delaware citizens equally;
6. The Department’s Hearing Officer’s Report, including its established record and the recommended proposed revised Amendments as set forth in Appendix “A,” are hereby adopted to provide additional reasons and findings for this Order;
7. The Department’s proposed regulatory Amendments, as initially published in the September 1, 2018 Delaware Register of Regulations, and then as revised, as set forth in Appendix “A” of the Hearing Officer’s Report, are adequately supported, are not arbitrary or capricious, and are consistent with the applicable laws and regulations. Consequently, they should be approved as final regulatory Amendments, which shall go into effect ten days after their publication in the next available issue of the Delaware Register of Regulations; and
8. The Department shall submit the proposed revised Amendments as final regulatory amendments to 7 DE Admin. Code 5101: Delaware Sediment and Stormwater Regulations, to the Delaware Register of Regulations for publication in its next available issue, and provide such other notice as the law and regulation require and the Department determines is appropriate.
In a legislative response to the Baker holdings, the General Assembly enacted Senate Bill 253 on June 24, 2016, 80 Del. Laws Ch. 274, and House Bill 194 on August 10, 2016, 80 Del. Laws Ch. 392. These Bills adopted interim standards governing development, while extending the duration of the emergency regulations, to allow the RAC to complete its work.
1.2 The purpose intent of this regulation is to enhance and extend the present erosion and sediment control activities and programs of the State for both rural and urban lands and to provide for control and management of stormwater runoff consistent with sound water and land use practices. These activities will reduce, to the maximum extent practicable, adverse effects of stormwater runoff on the water and lands of the State.
1.3.1 On and after January 1, 2014, unless Unless a particular activity is exempted by these regulations, a person shall not disturb land without an approved Sediment and Stormwater Management Plan from the Department or Delegated Agency. A Sediment and Stormwater Management Plan shall not be approved for a property unless it is consistent with the following items:
1.3.1.2 7 Del.C. Ch. 40, relating to erosion and sediment control and stormwater management; and
1.3.1.3 7 Del.C. Ch. 60, relating to the development, utilization, and control of the land, water, underwater and air resources of the State, and; including the current Delaware Construction General Permit (CGP).
1.3.1.4 Regulations Governing the Control of Water Pollution, Section 9.1.02, known as Special Conditions for Stormwater Discharges Associated with Construction Activities.
1.3.2.2 Plans approved to comply with previous regulations in effect prior to January 1, 2014 where construction has commenced may be extended based on the requirements in place at the time of original Plan approval. In no case shall the plan extension supersede the sunset provisions of the county or local government.
1.3.2.41.3.2.3 Commencement of construction means that the construction of the approved Plan is visible with the construction of a structure or infrastructure, including but not limited to roads, water and sewer lines, and stormwater management systems. General earth moving is not considered commencement of construction.
1.5.3 Excluding items covered by 1.7 Offset Provisions, the The Department shall consider and decide applications for a variance from the provisions of these Regulations if all of the following are established by the applicant.
1.5.3.3 If the variance were granted, the goals of these Regulations and the technical documents will be met with respect to the property in question.
1.5.7 The variance shall be effective from the date of its approval, until a final plan is approved unless the nature and scope of the project for which it was granted has changed not to exceed one year.
1.6.1.2.2 The fee schedule and revisions to the fee schedule of the Delegated Agency, with the concurrence of the Department, shall be subject to applicable State or local public notice requirements. State public notice requirements shall be governed by 7 Del.C. §6004.
16.2.1.1 The Owner shall submit when required to the Department or Delegated Agency a financial guarantee before the onset of construction activities. The financial guarantee will ensure that action can be taken by the Department or Delegated Agency to complete required elements of the approved Sediment and Stormwater Management Plan, at the Owner's expense, should the Owner fail to initiate, complete, or maintain those measures identified in the approved Sediment and Stormwater Management Plan after being given proper notice and within a reasonable time specified by the Department or Delegated Agency.
1.6.2.1.2 The financial guarantee may be extended beyond the time period specified to cover a reasonable period of time, not less than one year, for testing the practices during storm events and for initial maintenance activities. However, the Department or Delegated Agency may adopt provisions for a partial release of the financial guarantee upon the completion of specified stages or phases of development as outlined in accepted procedures.
1.81.7 These regulations are adopted pursuant to authority conferred by and in accordance with 7 Del.C. Ch. 40 and 7 Del.C. Ch. 60.
1.91.8 These regulations are not intended to interfere with, abrogate, or annul any other ordinance, rule or regulation, statute, or other provision of law. The requirements of these regulations should be considered minimum requirements, and where any provision of these regulations imposes restrictions different from those imposed by any other ordinance, rule or regulation, or other provision of law, whichever provisions are more restrictive or impose higher protective standards for human health or the environment shall be considered to take precedence.
1.101.9 If any section, subsection, sentence, clause, phrase or portion of these regulations is for any reason held invalid or unconstitutional by any court or competent jurisdiction, such provision and such holding shall not affect the validity of the remaining portions of these regulations.
1.111.10 Any person who undertakes or causes to be undertaken any land disturbing activities shall ensure that soil erosion, sedimentation, increased pollutant loads and changed water flow characteristics resulting from these activities are controlled so as to minimize pollution of state waters. The requirements of these regulations are minimum standards and a person's compliance shall not relieve the person from the duty of enacting all measures necessary to minimize pollution of, or detrimental impacts to state waters.
1.121.11 The conduct of all hearings conducted pursuant to these regulations shall be in accordance with the relevant provisions of 7 Del.C. Ch. 60.
1.131.12 The Department is responsible for the implementation and supervision of the sediment and stormwater program which is established by 7 Del.C. Ch. 40. The program shall be administered pursuant to these regulations. The Department may also develop and maintain a Technical Document to serve as a guide for the regulated community and Delegated Agencies in complying with Chapter 40 and these regulations.
Adequate conveyance means any system having sufficient capacity to transport the runoff generated during the Resource Protection Event, Conveyance Event, and Flooding Event; functions and discharges in a non-erosive manner; and does not adversely impact any offsite properties, conveyance system, stormwater facility, or State Waters.
Adverse impact means a negative impact resulting from a construction or development activity. The negative impact may include, but is not limited to, increased risk of flooding; degradation of water quality; increased sedimentation; reduced groundwater recharge; negative impacts on aquatic habitat; or threatened public health and safety.
Agricultural land management practices means those methods and procedures generally accepted by the Conservation Districts and used in the cultivation of land in order to further crop and livestock production and conservation of related soil and water resources.
Agricultural structure” means a structure on a farm used solely for agricultural purposes in which the use is exclusively in connection with the production, harvesting, storage, drying, or raising of agricultural commodities, including the raising of livestock. Structures used for human habitation, public use, or a place of employment where agricultural products are processed, treated, or packaged are not considered agriculture structures for the purposes of these regulations.
Applicant” means a person who has requested approval of a Sediment and Stormwater Management Plan through submittal of an application in accordance with these regulations or who has requested permission to conduct any activity subject to these regulations.
Best Available Technology available technology” or “(BAT)” means a level of technology based on the very best (state of the art) sediment and stormwater control and treatment measures that have been developed or are capable of being developed and that are economically achievable.
Best Management Practices management practices” or “(BMPs) means schedules of activities, prohibition of practices, maintenance procedures, and other management practices or measures to prevent or reduce the discharge of pollutants. BMPs include the following, among other practices and measures: structural and non-structural controls; treatment requirements; operating procedures and practices to control site runoff.
Biosolids” means solid or semi-solid material obtained from treated wastewater or animal manure.
Brownfield means any vacant, abandoned or underutilized real property the development or redevelopment of which may be hindered by the reasonably held belief that the real property may be environmentally contaminated.
Certified Construction Reviewer” or “CCR means those individuals, having passed a Departmental sponsored or approved training course and holding current certification, which provide on-site construction review for sediment control and stormwater management in accordance with these regulations.
Conservation plan means a customized document that outlines the use and best management practices of the natural resources on a parcel of land.
Conveyance Event event means the runoff event produced by a storm having an annual probability of occurrence of 10%.
Conveyance Event Volume event volume” or “(Cv)” means the volume of runoff generated by the Conveyance Event that is not otherwise reduced for the Resource Protection Event.
Dedication means transferring ownership of a stormwater management system to a delegated agency, public utility, municipality, stormwater utility, or private entity, along with all associated easements, escrow funds, and maintenance responsibilities.
Delegated Agency means the Conservation District, county, municipality, or State agency that has accepted responsibility in a jurisdiction for implementation of one or more elements of the Sediment and Stormwater Program within that jurisdiction.
Delegation means the acceptance of responsibility by a Conservation District, county, municipality, or State agency for the implementation of the Sediment and Stormwater Program.
Department” means the Department of Natural Resources and Environmental Control.
Designated Watershed watershed or Subwatershed subwatershed” means a watershed or subwatershed proposed by a conservation district, county, municipality, or State agency and approved by the Department. The Department may establish additional requirements due to existing water quantity or water quality problems. These requirements shall be implemented on an overall watershed or subwatershed master plan developed for water quality or water quantity protection.
Detailed plan means a plan developed by a Licensed Professional in the State of Delaware which does not meet standard plan criteria.
Drainage area means that area contributing runoff to a single point measured in a horizontal plane, which is enclosed by a ridge line.
Easement means a grant or reservation by the Owner of land for the use of land by others for a specific purpose or purposes, and which must be included in the conveyance of land affected by the easement.
Effective imperviousness”, for the purposes of these Regulations, means the equivalent percentage of a site’s impervious area that directly contributes stormwater runoff during the Resource Protection Event after all runoff reduction practices have been implemented.
Erosion and sediment control means the control of solid material, both mineral and organic, during a land disturbing activity, to prevent its transport out of the disturbed area by means of wind, water, gravity, or ice.
Final stabilization” means that:
Financial guarantee” means a bond, security, letter of credit, etc. provided by the Owner to serve as a payment source should the Owner fail to meet the obligations and requirements of the approved Sediment and Stormwater Management Plan.
Flooding Event event means the runoff event produced by a storm having an annual probability of occurrence of 1.0%.
Flooding Event Volume event volume” or “(Fv)” means the volume of runoff generated by the Flooding Event that is not otherwise reduced for the Resource Protection Event and the Conveyance Event.
"Forest" means a biological community dominated by trees and other woody plants covering a land area of one contiguous acre or greater, and that have at least 100 trees per acre with at least 50% of those trees having a two inch or greater diameter at 4.5 feet above the ground and larger. Forest does not include orchards or other stands of trees having a curve number equivalent to "woods-grass combination". To determine whether a site meets the definition of a forest at the baseline condition of [20122017], the Department or its authorized Delegated Agency may use data from various sources, including but not limited to [2012] Land Use/Land Cover data, historic and recent aerial photography, field collected data, etc.
Functional Equivalency equivalency” means alternative measures that are consistent with the policies, procedures, technical specifications, and advisory provisions found in the [Technical Document regulatory guidance documents], and which satisfy these Regulations.
Impervious surface” means a surface which either prevents or retards the entry of water into the soil.
Infiltration means the passage or movement of water into the soil profile.
"Inspection port" means an appurtenance installed within a stormwater management system to allow for observation of conditions, including water level, located below the surface.
Land disturbing activity” means a land change or construction activity for residential, commercial, industrial, and institutional land development which may result in soil erosion from water or wind, or the movement of sediments or pollutants into state waters or onto lands in the State; or which may result in accelerated stormwater runoff, including, but not limited to, clearing, grading, excavating, transporting and filling of land.
Licensed Professional in the State of Delaware means a design professional licensed under 24 Del.C. Ch. 2, 24 Del.C. Ch. 27, or 24 Del.C. Ch. 28.
Maintenance” means the work of keeping stormwater management systems including access routes and appurtenances (grade surfaces, walls, drains, dams and structures, vegetation and other protective devices) in a safe and functioning condition as the system was designed. Routine or minor maintenance includes grass mowing and trimming, debris removal, minor sediment removal, filling eroded areas and animal burrows, and removal of trees and shrubs on embankments. Non-routine or major maintenance includes structural repair, major sediment removal and major erosion repair, and invasive aquatic vegetation removal.
Maximum Extent Practicable extent practicable” or “MEP” means, for the purpose of these Regulations, using stormwater management measures, techniques and methods that are available and capable of being implemented while taking into consideration cost, available technology, and project site constraints.
Notice of Completion means a document issued by the Department or Delegated Agency at the end of project construction when all items and conditions of the approved Sediment and Stormwater Management Plan have been satisfied, post construction verification documents demonstrate that the stormwater management systems have been constructed in accordance with the approved Sediment and Stormwater Management Plan, and final stabilization of disturbed areas on the site has been achieved.
Offset” means an alternate to strict adherence to the regulations including, but not limited to trading, banking, fee-in-lieu, or other similar program that serves as compensation when the requirements of these regulations cannot be reasonably met on an individual project basis.
Operation and Maintenance Plan” means the plan which identifies required maintenance for stormwater management systems.
Owner” means a person who has a legal interest in lands of this State, or who has an equitable interest in lands of this State, except when a person holds an interest in those lands as a security interest, unless through foreclosure or other action the holder has taken possession of those lands, and who undertakes, or for whose benefit, activities subject to these regulations are commenced or carried out on those lands, or the person responsible for maintenance of stormwater management systems constructed to comply with these regulations on those lands.
Performance-based approach means a stormwater quantity management technique that utilizes an analytical process to determine compliance.
Person means a State or federal agency, individual, partnership, firm, association, joint venture, public or private corporation, trust, estate, commission, board, public or private institution, utility, cooperative, municipality or other political subdivision of this State, an interstate body or any other legal entity.
Permanent stabilization” means the establishment of perennial vegetation by application of soil amendments, seed, and mulch in accordance with methods accepted by the Department on disturbed areas that have reached final grade in order to stabilize the soil, prevent erosion, and reduce sediment and runoff to downstream or offsite areas.
Post construction verification documents” means a set of surveyed plans reflecting the as-built condition of stormwater management measures and may also include supporting computations and specifications as required by the Department or the Delegated Agency.
"Pretreatment" means a mechanism at or before an inlet to a stormwater management practice that reduces gross pollutants and sediment from compromising the performance and to maximize the maintenance interval of the practice.
Redevelopment”, including brownfield development, means a construction, alteration or improvement, including but not limited to the demolition or building of structures, filling, grading, paving, or excavating, where existing land use is residential, commercial, industrial, or institutional. Ordinary maintenance activities, remodeling of existing buildings, resurfacing of paved areas, and exterior changes or improvements are typically not considered redevelopment activities for the purposes of these regulations.
Resource Protection Event protection event” means the runoff event produced by a storm having an annual probability of occurrence of 99%.
Resource Protection Event Volume protection event volume” or “(RPv)” means the annualized volume of runoff generated by the Resource Protection Event.
Responsible personnel” means a foreman or superintendent who is in charge of on-site clearing and land disturbing activities for sediment and stormwater control associated with a construction project.
Runoff reduction practices” means stormwater best management practices that reduce total runoff volume from a developed site through canopy interception, surface recharge, evaporation, rainfall harvesting, engineered infiltration, or evapotranspiration and may include practices that delay the delivery of stormwater to a surface discharge.
Sediment” means soils or other surficial materials transported or deposited by the action of wind, water, ice or gravity as a product of erosion.
Sediment and Stormwater Management Plan” means a plan for the control of soil erosion, sedimentation, stormwater quantity, and water quality impacts resulting from a land disturbing activity, through both the construction and post construction phases of development.
Standard plan” means a set of pre-defined standards or specifications for minor land disturbing activities that may preclude the need for the preparation of a detailed plan under specific conditions.
Standards-based approach means a stormwater quantity management technique that utilizes a pre-determined discharge rate to determine compliance.
State waters” means any and all waters, public or private, on the surface of the earth which are contained within, flow through or border upon the State or any portion thereof.
"Stone" means a hard non-metallic mineral building material, and for the purposes of this regulation shall be interchangeable with "gravel" and "aggregate".
Stormwater” means the runoff of water from the surface of the land resulting from precipitation, or snow or ice melt.
Stormwater management” means:
"Stormwater management offset" means an alternative method of compliance to the regulations including, but not limited to, trading, banking, fee-in-lieu, or other similar program.
"Stormwater management offset district" means an organization established to administer stormwater management offsets established under Department authorization.
Stormwater management system” means vegetative, structural, and other facilities or measures, singularly or in combination, as defined in Section 11.0, that provide stormwater management.
Stormwater utility” means an administrative organization that has been established for the purposes of funding sediment control, stormwater management or flood control planning, design, construction, maintenance, and overall resource needs by authorized and imposed charges.
Temporary stabilization” means planting quick-growing vegetation and applying anchored straw mulch or other means to stabilize the soil and prevent erosion of a disturbed area until permanent vegetation or other stabilization measures can be established.
"Third party CCR" means, for the purposes of these regulations, any individual CCR that is not an employee of the owner or a contractor of the construction activity, excluding the site designer.
Tidal waters means any water that alternately rises and falls in a predictable and measurable rhythm or cycle due to the gravitational attraction of the moon and sun and is under the regulatory authority of 7 Del.C. Ch. 72.
Transfer” means to convey responsibility for maintenance of a stormwater management system to a new Owner.
Variance means a permitted deviation from an established rule or regulation, or plan, or standard or procedure.
Water quality” means those characteristics of stormwater runoff from a land disturbing activity that relate to the chemical, physical, biological, or radiological integrity of water.
Water quantity” means those characteristics of stormwater runoff that relate to the rate, volume and duration of flow to downstream areas resulting from land disturbing activities.
Watershed means the drainage area contributing stormwater runoff to a single point.
Watershed plan” means a comprehensive study of the activities and sources that contribute to water quality or water quantity problems and identifies the location of those problem areas within a specific watershed boundary. It also serves as a framework for how, where and what stormwater management tools will be applied to address those water quality or water quantity problems.
3.1 All projects requiring approval of a detailed Sediment and Stormwater Management Plan are subject to a three-step approval process. Step 1 of the plan approval process is scheduling and conducting the project application meeting Project Application Meeting. Step 2 of the plan approval process is submission of the preliminary Preliminary Sediment and Stormwater Management Plan. Step 3 of the plan approval process is submission of the Sediment and Stormwater Management Plan.
3.2.1 All Owners are required to hold a project application meeting Project Application Meeting with the Department or Delegated Agency, unless the requirement for a project application meeting is waived in writing by the Department or Delegated Agency as determined on a case-by-case basis.
3.2.2 Before scheduling the project application meeting Project Application Meeting, the Owner shall submit a Stormwater Assessment Study (SAS) to the Department or Delegated Agency.
3.2.3 At the project application meeting Project Application Meeting the Stormwater Assessment Study will be reviewed as well as potential approaches for stormwater management and opportunities to reduce runoff rates, volumes, and pollutant loads.
3.2.4 A document listing the topics of discussion and items agreed upon will be developed during the meeting and concurred by all attendees. Project Application Meeting discussion and agreement items will be documented in meeting minutes prepared by the Owner or the Owner's Representative and distributed to all in attendance.
3.3.1 The preliminary Preliminary Sediment and Stormwater Management Plan submittal shall include preliminary plans for the site, as well as the schematic erosion and sediment control plan, with supporting hydrologic and hydraulic calculations necessary for the Department or Delegated Agency to determine compliance with these regulations.
3.3.2 If significant changes are proposed on the preliminary Preliminary Sediment and Stormwater Management Plan from the plan that was discussed at the project application meeting Project Application Meeting, such as a change in land use or changes that result in a different rating on the Stormwater Assessment Report, the Owner may be required to repeat the project application meeting Project Application Meeting step of the process.
3.4.1 The Sediment and Stormwater Management Plan submittal shall consist of the following elements: Construction Site Stormwater Management Plan including pollution prevention elements, Post Construction Stormwater Management Plan, final hydrologic and hydraulic computations, Operation and Maintenance Plan, and a copy of the preliminary Record Plan as required by the local land use approval agency. The plan shall also include the following notes:
3.4.2 If significant changes are proposed on the Sediment and Stormwater Management Plan from the preliminary Preliminary Sediment and Stormwater Management Plan, such as a change in the size or location of proposed BMPs, the Owner may be required to repeat the preliminary Preliminary Sediment and Stormwater Plan step of the process.
3.5.1 The Department or Delegated Agency shall have 30 calendar days from receipt of either the preliminary Preliminary Sediment and Stormwater Management Plan or final Sediment and Stormwater Management Plan to complete the review and have either the approval or review comments transmitted to the Owner, unless the 30-calendar day period cannot be met, in which case the Department or Delegated Agency shall notify the Owner in writing of the reasons for delay, and an expected time period not to exceed an additional 30 calendar days, for when that review will be completed.
3.6.1 Approved plans remain valid for 3 five years from the date of an approval, unless specifically extended by the Department or Delegated Agency. The basis for extension may include, but is not limited to, the following items:
3.7.3 The inclusion of an activity into the standard plan classification does not exclude that activity from the requirements of 7 Del.C. Ch. 40. Rather, the standard plan precludes that activity from the necessity of a detailed plan review for a qualifying project.
3.7.5 A detailed plan may be required for a site that would otherwise meet standard plan criteria as deemed appropriate but does not meet the intent of the regulations as determined by the Department or Delegated Agency on a case-by-case basis. The Department or Delegated Agency may require a detailed plan prior to approval or at any time during construction.
[3.7.13.1.3 One of the following is met:
3.7.16.1 Applicability criteria. Land disturbance is for maintenance of a stormwater management facility having a design on file with [DNREC or a Delegated Agency of the DNREC Sediment and Stormwater Program the Department or Delegated Agency].
[3.7.22.1.4 One of the following is met:
3.103.9 Before project completion the Owner shall submit a final post construction stormwater management Operation and Maintenance Plan for the entire stormwater management system. Operation and Maintenance Plans remain valid for the life of the stormwater management system.
3.113.10 Post construction verification documents shall be submitted to the Department or Delegated Agency within 60 calendar days of completion for stormwater management systems. The post construction verification documents shall compare the designed and constructed elements of the stormwater management system, and bear the seal of a Licensed Professional in the State of Delaware. A final construction review and approval by the Department or Delegated Agency is required before a financial guarantee shall be released, and before a Notice of Completion may be issued.
4.1 The Technical Document may be utilized as a reference for the design and preparation of construction site stormwater management plans. Alternative measures that provide functional equivalency may be considered on a case-by-case basis in accordance with Section 1.14 of these Regulations. All construction site stormwater management practices shall be consistent with the current version of the Delaware Erosion and Sediment Control (ESC) Handbook. A proposal to use temporary control measures that are not included in the current version of the Delaware ESC Handbook shall be submitted to the Department for approval. The proposal shall be accompanied by supporting documentation as necessary to determine appropriateness of the proposed temporary control measure for the proposed use.
4.3 Best available technology (BAT) shall be employed to manage turbid discharges in accordance with requirements of 7 Del.C. Ch. 60, Regulations Governing the Control of Water Pollution, Section 9.1.02, known as Special Conditions for Stormwater Discharges Associated with Construction Activities, and Department policies, procedures, and guidance. and the current Delaware Construction General Permit (CGP).
4.4.1 Use of standard details from the Delaware Erosion and Sediment Control Handbook for design of construction site stormwater management BMPs is limited to sites where no more than 20 acres draining to a common discharge point will be disturbed at one time. Unless an exception is approved on a case by case basis for a specific type of activity by the appropriate plan approval agency, not more than 20 acres may be disturbed at any one time. This will necessitate the phasing of construction on sites in excess of 20 acres to minimize areas exposed of ground cover and reduce erosion rates. Disturbance of a second 20 acre section may not proceed until temporary or permanent stabilization of the first 20 acre section is accomplished.
4.4.2 Construction site stormwater management BMPs intended to manage areas If approved by the Department or Delegated Agency sites may disturb greater than 20 acres shall have supporting design computations, including but not limited to storage, conveyance, stability, and treatment capabilities. Sites having disturbed areas greater than 20 acres shall comply with the following:
4.4.44.4.3 All plans shall include a limit of disturbance line (L.O.D.) establishing the maximum necessary extent of land disturbance required to implement and accomplish the permitted site construction for land disturbing activities subject to these Regulations.
5.1 The Technical Document may be utilized as a reference for the design and preparation of post Post construction stormwater management plans shall be designed in accordance with the following:. Alternative measures that provide functional equivalency may be considered on a case-by-case basis in accordance with Section 1.14 of these Regulations.
5.1.2 Residential Land disturbance including but not limited to residential, commercial, institutional, agricultural structures, or industrial developments shall apply these stormwater management criteria to land development as a whole. Smaller sites, such as individual residential lots in new subdivisions that are part of a larger, common plan of development or sale shall be subject to these requirements as part of that larger plan.
5.1.3 No portion of a stormwater system that is owned and maintained by a joint ownership such as a homeowner’s association or maintenance corporation in a residential development shall be located on private property, except for those areas designated as common areas, community open space, community-owned property, [or] jointly owned property, or within a recorded easement dedicated to public use. Shared facilities located on private property shall be within a recorded easement. A stormwater system owned by a single Owner, as in the case of a commercial, institutional or industrial development, may be located on that Owner’s private property.
5.1.4 If runoff from a land development will flow to a permitted or non-permitted municipal separate storm sewer system (MS4) or other publicly maintained drainage infrastructure, the land development applicant shall notify the system’s owner of the intent to discharge into the system before plan approval. The Department, Delegated Agency, or system’s owner may require the land development applicant to demonstrate that the system has adequate conveyance.
5.1.5 All applications that propose to use infiltration or natural recharge shall include a soils investigation in accordance with subsection 12.1 of these regulations to determine the appropriate design criteria.
5.2.3 Compliance with [this section subsection 5.2] shall be accomplished to the maximum extent practicable through the following provisions:
5.2.3.1 Runoff from disturbed areas that were wooded or meadow in the pre-developed condition shall be reduced using runoff reduction practices to an equivalent wooded condition. Treatment of runoff from the RPv event with Best Management Practices (BMPs) as set forth in [the Post-Construction Stormwater Management BMP Standards and Specifications Section 11.0] shall meet the following requirements:
5.2.3.1.5 Any additional runoff volume treated by BMPs in excess of that necessary to achieve site compliance in accordance with [this section subsection 5.2] may be used as a credit in accordance with Section 13.0 Offset Provisions.
5.2.3.3 Additional water quality treatment BMPs may be provided if the runoff reduction requirements of this section are not sufficient to meet Total Maximum Daily Load (TMDL) requirements for the receiving water. Pollutant reductions achieved through the use of these treatment BMPs may be used to partially reduce a runoff reduction offset requirement provided in accordance with Section 5.2.3.2.2 above. An offset shall be provided in accordance with Section 13.0 of these regulations for any portion of the RPv that does not meet the requirements of subsection 5.2.3.1 above.
5.2.4 Projects that qualify for and meet standard plan criteria developed by the Department in accordance with subsection 3.7 of these regulations shall be considered in compliance with the Resource Protection Event criteria.
5.3.3 Compliance with [this section subsection 5.3] shall be accomplished through the following provisions:
5.3.3.1 The Cv shall be reduced to the maximum extent practicable using runoff reduction practices. For any portion of the Cv that is not reduced, quantity management shall be provided using either a standards-based or performance-based approach managed using BMPs as set forth in [the Post- Construction Stormwater Management BMP Standards and Specifications Section 11.0] such that there is no adverse impact by limiting the increase in the downstream post-developed water surface elevation to no more than 0.05 feet; or
5.3.3.25.3.3.3 Provisions will be made or exist for a non-erosive conveyance system to tidal waters by either a closed drainage system or by open channel flow that has adequate conveyance for the Cv; or
5.3.3.35.3.3.4 Demonstration that the location of a project within a watershed would aggravate flooding or channel erosion by the imposition of peak control requirements, as evidenced by a downstream analysis approved by the Department or Delegated Agency that shows the inflection point of the site hydrograph occurs prior to and is less than the peak of the upstream hydrograph; or
5.3.3.45.3.3.6 The proposed project will generate only a de minimis discharge and will have no adverse impact on the receiving wetland, watercourse or downstream property as determined on a case-by-case basis.
5.3.4 Projects that qualify for and meet standard plan criteria developed by the Department in accordance with subsection 3.7 of these regulations shall be considered in compliance with the Conveyance Event criteria.
5.4.3 Compliance with [this section subsection 5.4] shall be accomplished through the following provisions:
5.4.3.1 The Fv shall be reduced to the maximum extent practicable using runoff reduction practices. For any portion of the Fv that is not reduced, quantity management shall be provided using either a standards-based or performance-based approach managed using BMPs as set forth in [the Post- Construction Stormwater Management BMP Standards and Specifications Section 11.0] such that there is no adverse impact by limiting the increase in the downstream post-developed water surface elevation to no more than 0.05 feet; or
5.4.3.25.4.3.3 Provisions will be made or exist for a non-erosive conveyance system to tidal waters by either a closed drainage system or by open channel flow that has adequate conveyance for the Fv; or
5.4.3.35.4.3.4 Demonstration that the location of a project within a watershed would aggravate downstream flooding or channel erosion by the imposition of peak control requirements, as evidenced by a downstream analysis approved by the Department or Delegated Agency that shows the inflection point of the site hydrograph occurs prior to the peak of the upstream hydrograph; or
5.4.3.45.4.3.6 The proposed project will generate only a de minimis discharge and will have no adverse impact on the receiving wetland, watercourse, or downstream property as determined on a case-by-case basis.
5.4.4 Projects that qualify for and meet standard plan criteria developed by the Department in accordance with subsection 3.7 of these regulations shall be considered in compliance with the Flooding Event criteria.
5.5.2 The Department or Delegated Agency, at its discretion, may require alternative stormwater treatment practices or criteria if a receiving waterbody has been identified as impaired, or designated with a specific pollutant reduction target necessary to meet State of Delaware water quality regulations. Such requirements shall be adopted in accordance with Title 29.
5.5.3 The Department or Delegated Agency, at its discretion may require alternative stormwater treatment practices designed to reduce pollutant loading from a specific source, including but not limited to the discharge from an industrial site regulated under the National Pollutant Discharge Elimination System (NPDES).
5.6.1 The Department recognizes the benefits of redevelopment. The requirements under [this section subsection 5.6] are intended to encourage redevelopment while establishing compliance criteria that meet the overall goals and intent of these regulations.
5.6.35.6.2 Compliance with the Resource Protection Event as defined in subsection 5.2.2 shall be accomplished to the maximum extent practicable for redevelopment projects through the following provisions:
5.6.45.6.3 Any redevelopment project, including a contaminated or Brownfield site, that increases the rate, volume or duration of flow to a new or existing point of discharge during the Conveyance Event shall comply with the requirements of Section subsection 5.3.
5.6.55.6.4 Any redevelopment project, including a contaminated or Brownfield site, that increases the rate, volume or duration of flow to a new or existing point of discharge during the Flooding Event shall comply with the requirements of Section subsection 5.4.
6.1.2 The Owner may refer to the specifications contained in the Handbook or take functionally equivalent measures to install and maintain construction site stormwater management BMPs in accordance with the approved plan.
6.1.36.1.2 The Owner shall comply with the requirements contained in Chapter 60 of Title 7 of the Delaware Code Section 9.1.02 of Delaware’s Regulations Governing the Control of Water Pollution, 7 DE Admin. Code 7201 including the current Delaware Construction General Permit (CGP).
[6.1.2.1 The Owner or Owner's representative shall maintain the approved Sediment and Stormwater Management Plan at the construction site.
6.1.3.16.1.2.2 The Owner or Owner’s representative shall conduct weekly construction reviews of the construction site stormwater management BMPs and post construction stormwater management systems.
6.1.3.26.1.2.3 The Owner or Owner’s representative shall conduct construction reviews of the construction site stormwater management BMPs and post construction stormwater management systems following rainfall events producing runoff.
6.1.3.36.1.2.4 The Owner or Owner’s representative shall maintain written records at the construction site of all construction reviews at the construction site.]
6.1.46.1.3 The Department or Delegated Agency shall have the authority to require revisions to the approved Sediment and Stormwater Management Plan. The Owner is responsible for implementation of plan revisions when deficiencies are noted on the site by the Department or Delegated Agency construction reviewer.
6.1.56.1.4 The Owner shall certify to the Department or Delegated Agency that responsible personnel involved in the construction project have successfully completed the Contractor Training Program before initiation of a land disturbing activity. Responsible personnel shall implement the Sediment and Stormwater Management Plan fully through daily oversight of the construction site and guidance of construction personnel while a land disturbing activity is taking place.
6.1.66.1.5 For projects developing 20 acres or greater, and including those projects that require discharge monitoring for the maximum daily discharge limitation under Federal requirements, When directed by the Department or Delegated Agency, the Owner shall acquire the services of a third party Certified Construction Reviewer to perform weekly construction reviews of the approved Sediment and Stormwater Management Plan elements as well as construction reviews of installation of stormwater management systems. Any project, regardless of its size, may be required by the Department or Delegated Agency, to have a Certified Construction Reviewer on a case-by-case basis. Sediment and Stormwater Management Plans approved by the Department shall have a Certified Construction Reviewer. The Department or Delegated Agency may, at its discretion and following a written request, modify Certified Construction Reviewer reporting frequency for a particular site if site conditions warrant.
6.1.96.1.8 The Owner shall notify the Department or Delegated Agency any time a new Certified Construction Reviewer begins providing construction review for the site.
6.1.106.1.9 Upon written notice by the Department, Delegated Agency, or Certified Construction Reviewer, any portion of the work which does not comply with the approved Sediment and Stormwater Management Plan or these regulations shall be corrected by the Owner within the time period specified in the written notice.
6.2 Contractor Training Program Requirements
6.2.2 Contractor Training shall be required of a foreperson or superintendent who is in charge of on-site clearing and land disturbing activities for construction projects subject to the requirements of these regulations.
6.3.16.3.2 The Certified Construction Reviewer shall function under the direction of a registered professional engineer (P.E.) licensed to practice engineering in the State of Delaware. The following applies to the P.E.'s responsibilities:
6.3.26.3.3 Certified Construction Reviewers shall attend and successfully complete the Departmental sponsored or approved Certified Construction Reviewer course. The Certified Construction Reviewer shall be responsible for reviewing construction activities and reporting on the adequacy of construction in accordance with the approved Sediment and Stormwater Management Plan, these regulations, and training received in the Certified Construction Reviewer training course.
6.3.36.3.4 Certification as a CCR shall be valid for five years. Recertification may extend certification for an additional five years.
6.3.46.3.5 A Certified Construction Reviewer who is not performing the duties prescribed by Section 6.1.8 subsection 6.3 of these regulations this regulation may be referred by the local Delegated Agency to the Department for action by providing written notification to the Department and supporting documentation.
6.3.56.3.6 In a situation where a Certified Construction Reviewer’s certification is being suspended or revoked, an opportunity for hearing before the Secretary or his designee shall be provided. During a suspension, the Certified Construction Reviewer shall not be allowed to provide construction reviews in accordance with these regulations on any construction sites within the state.
6.5.2 A pre-construction meeting shall be required. The pre-construction meeting shall be held on site, unless another location is approved by the Department or Delegated Agency on a case-by-case basis. The required attendees for a pre-construction meeting are the owner or owner's representative, the site project manager, site contractor, Certified Construction Reviewer (if required), the Responsible Person, and the Department or Delegated Agency representative.
6.5.6 Upon project completion a final construction review shall be conducted and a final review report shall be completed by the Department or Delegated Agency to ensure compliance with the approved Sediment and Stormwater Management Plan. The Department or Delegated Agency shall issue a Notice of Completion for a project when all of the following criteria have been met:
7.1 Stormwater management systems constructed to comply with 7 Del.C. Ch. 40 and these regulations shall be maintained in accordance with the provisions of this section.
7.2.27.2.1 The Owner shall ensure that the stormwater management system is functioning in accordance with the approved engineering design, within the tolerances of the accepted post construction verification documents, and in compliance with these regulations. The Owner will promptly repair and restore stormwater management systems.
7.2.2.17.2.1.1 Such repairs, restoration, or maintenance shall be conducted in accordance with the approved Sediment and Stormwater Management Plan, the Operation and Maintenance Plan, Standard Guidelines for Operation and Maintenance of Stormwater Management Systems, and directions provided by the Department or Delegated Agency.
7.2.2.27.2.1.2 When the Department or Delegated Agency gives direction for maintenance, those maintenance activities shall be conducted by the Owner within the time period established by the Department or Delegated Agency.
7.2.37.2.2 Any change made to the stormwater management system shall require the Owner to obtain approval of the Department or Delegated Agency, including updating of the Operation and Maintenance Plan and Planting Plan details as necessary.
7.2.47.2.3 The Owner shall submit a scope of work for non-routine maintenance to the Department or Delegated Agency for approval prior to implementation.
7.2.57.2.4 Maintenance responsibilities may be shared through a legal agreement between the Owner and another entity such as a delegated agency, public utility, municipality, stormwater utility, maintenance company, or other private entity. Responsibility for maintenance shall be joint and several among the parties to the agreement to share those responsibilities.
7.2.67.2.5 If the Sediment and Stormwater Management Plan includes structural or nonstructural stormwater management measures located within a tax ditch right-of-way the Owner shall enter into an agreement with the tax ditch organization for maintenance of those stormwater management measures.
8.2.2 Notification of plan inadequacy and the establishment of a date certain for the Owner to submit a revised Sediment and Stormwater Management Plan to the Department or Delegated Agency and to receive its approval with respect thereto. The Department shall notify the Delegated Agency in a timely manner of what enforcement action is taken on the site.
9.1.1 Program elements that are delegated shall be implemented according to Chapter Chapters 40 and 60 of Title 7 of the Delaware Code and these Regulations.
9.4 The Secretary shall, in writing, grant or deny delegation on or before April 1 of the year during which delegation is sought. The Secretary shall not deny a request for delegation unless opportunity has been afforded to the appropriate officials from the agency requesting delegation to present arguments. Delegation shall be effective July 1 of that year and extend no more than three five years, unless renewed. In the event that the Department does not act on the renewal request by April 1, the Delegated Agency submitting the request would be entitled to continue operating for a subsequent three five year time period unless action is taken by the Department to suspend the program.
9.5 Delegation of program elements shall be granted for a maximum time period of three five years. After three five years a new application to the Department must be made. During the period for which delegation has been granted, the Department will evaluate delegation implementation, coordinate review findings with the Delegated Agency, and determine if the new delegation should be granted.
9.6 Based on the Department’s evaluation of Delegated Agency performance, the Department may determine that re-delegation of program elements may be granted for a time period of less than three five years. A delegation period of less than the maximum of three five years shall be considered a probationary delegation and specific improvement items shall be provided to the Delegated Agency. If program implementation is not improved during the probationary delegation, delegation may not be renewed beyond the probationary delegation period.
10.4 The authority for the creation of the stormwater utility and the imposition of charges to finance sediment and stormwater activities is conferred in 7 Del.C. Ch. 40. The implementation of a stormwater utility by means of a local ordinance shall not be deemed a limitation or repeal of any other powers granted by State statute.
11.1.3.2 A minimum vertical distance of two feet must be provided between the bottom of the infiltration practice and the seasonal high water table as determined by [the soil investigation procedures subsection 12.1] or bedrock layer. The minimum vertical distance of two feet may be relaxed if a groundwater mounding analysis or piezometer testing has been performed by a qualified professional.
11.1.6.5 For design purposes, the field verified infiltration rate shall have a factor of safety applied in accordance with [Soil Investigation Procedures subsection 12.1] to account for potential compaction during construction and to approximate long term infiltration rates.
11.1.7.3 The infiltration rate and separation from groundwater of the constructed infiltration practice shall be verified prior to completion of construction in accordance with [the Soil Investigation Procedures subsection 12.1]. The results shall be included with the Post Construction Verification Documentation upon project completion.
11.2.3.1 A minimum vertical distance of two feet must be provided between the bottom of the infiltrating bioretention practice and the seasonal high water table as determined by [the soil investigation procedures the procedures in subsection 12.1] or bedrock layer. The minimum vertical distance of two feet may be relaxed if a groundwater mounding analysis or piezometer testing has been performed by a qualified professional.
11.2.8.3 For infiltrating bioretention systems, confirmatory infiltration testing and verification must be completed prior to completion of construction in accordance with [the Soil Investigation Procedures subsection 12.1]. The results shall be included with the Post Construction Verification Documentation upon project completion.
11.3.3.2.1 Infiltration testing in accordance with [the Soil Investigation Procedures subsection 12.1] shall be required.
11.3.5.2.1 For design purposes, the field verified infiltration rate shall have a factor of safety applied in accordance with [the Soil Investigation Procedures subsection 12.1] to account for potential compaction during construction and to approximate long term infiltration rates.
11.3.6.3 The infiltration rate and separation from groundwater of the constructed permeable pavement practice shall be verified prior to completion of construction in accordance with [the Soil Investigation Procedures subsection 12.1]. The results shall be included with the Post Construction Verification Documentation upon project completion.
11.10.3.1.4 [Soil Investigation Procedures Subsection 12.1] shall be followed for testing.
11.11.8.3.3 When an underdrain is specified a needled, non-woven, polypropylene geotextile having a flow rate (ASTM D4491) ≥110 gallons per minute per square foot (gal/min/sf) and an apparent opening size (ASTM D4751) of US #70 or #80 sieve shall be placed beneath the filter media and above the underdrain gravel layer.
11.12.6.11.2 The average groundwater elevation as determined by [the Soil Investigation Procedures subsection 12.1] shall be below the bottom of the Wetland Swale. Only the seasonal high groundwater as determined by the Soil Investigation Procedures may intersect the bottom of the Wetland Swale.
11.12.6.12.1.3 The average groundwater elevation as determined by the Soil Investigation Procedures shall be below the wetland bottom of the Ephemeral Constructed Wetland. Only the seasonal high groundwater as determined by [the Soil Investigation Procedures subsection 12.1] may intersect the bottom of the Ephemeral Constructed Wetland. If the seasonal high groundwater intersects the bottom of the Ephemeral Constructed Wetland, the wetland shall be modeled considering the elevation of the seasonal high groundwater.
11.13.3.1 Soil investigations must be conducted in accordance with [Soil Investigation Procedures subsection 12.1] to determine the suitability of the soils to meet recommended embankment and permanent pool criteria.
11.14.3.1 The water table or bedrock is located within two feet of the soil surface. [Soil Investigation Procedures Subsection 12.1] shall be followed for determination of depth to the limiting layer.
11.14.5.1.4 Conduct soil test to determine whether any further [nutritional nutrient] requirements, pH adjustment, and organic matter adjustments are necessary for plant growth.