7 Del. Admin. Code § 7101-5.0
Current through Register Vol. 28, No. 3, September 1, 2024
Section 7101-5.0 - Small Systems ([LESS THAN] 2,500 GPD)5.1 This section prescribes the necessary soils investigations, permitting and installation requirements, operation and maintenance procedures and waiver applications for all on-site wastewater treatment and disposal systems with daily flow rates of < 2,500 gallons, including but not limited to all conventional, innovative/alternative, holding tanks and community on-site wastewater treatment and disposal systems (OWTDS).5.2 Soil Investigations 5.2.1 Site Evaluation Procedures 5.2.1.1 A site evaluation is the first step in the process of obtaining a construction permit for an on site wastewater treatment and disposal system. Any person applying for a permit to install a new or replacement on site wastewater treatment and disposal system shall first obtain a site evaluation report prepared by a Class D soil scientist. The Department shall only conduct site evaluations for Home Rehabilitation Loan Programs (HRLP), block grant households, State Revolving Fund (SRF) sites and other qualifying income programs with similar criteria.5.2.1.2 Each report shall be applicable to one residential or commercial structure. At a minimum, each report must include; approval page(s) (excluding sites not suitable for conventional on-site wastewater treatment and disposal systems (OWTDS)), report page(s), site drawing, soil profile notes, zoning verification form and the appropriate fee. The site evaluation report shall identify specific site conditions or limitations including, but not limited to, isolation and separation distances, slopes, existing wells, cuts and fills, and unstable landforms.5.2.1.3 The Class D soil scientist shall specify on the approval page the type(s) of on-site wastewater treatment and disposal system(s), suitable under these regulations that may be constructed in the acceptable on-site disposal area(s) as indicated on the site drawing. Any other on-site wastewater treatment and disposal options available in the evaluated area shall be specified by the Class D soil scientist. The scientist shall either assign a percolation rate (see Exhibit Y) or have the appropriate hydraulic conductivity or percolation test(s) conducted in the materials interpreted to be the most hydraulically limiting within the upper 60 inches in the proposed disposal area. The estimated percolation rate should take into consideration, but not be solely governed by, the slowly permeable material. Horizons in contact with or immediately within the required vertical separation distance may have more relevance than layers much deeper in the profile. 5.2.1.3.1 Percolation rates, actual or estimated, > 120 minutes per inch (mpi) are very slowly permeable and constitute a limiting layer. Such sites shall not be suitable for new construction, except when;5.2.1.3.1.1 Very slowly permeable horizon(s) can be removed (see sand-lining); or5.2.1.3.1.2 The required separation distance above the very slowly permeable horizon(s) can be met and maintained (unsaturated permeable soils over very slowly permeable soils); or5.2.1.3.1.3 Interpretations are to be made in conjunction with DNREC Environmental Scientist(s) to ensure all limiting conditions are addressed prior to making final site suitability determination.5.2.1.3.1.4 For design purposes;5.2.1.3.1.4.1 For systems with a separation distance of <= 24 inches the assigned percolation rate must be determined based on the most limiting layer above or below (after removal or sand-lining) the very slowly permeable soils or 75 mpi, whichever is greatest. Where the separation distance is > 24 inches, the minimum percolation rate assigned will be 60 mpi. The Class D soil scientist/site evaluator has the discretion to estimate a slower percolation rate than stated based on site specific constraints and professional experience.5.2.1.4 A site drawing drawn to scale showing the information referenced in Section 5.2.1.9. All site drawings are required to show a reference point (e.g. a numbered utility pole, telephone or electrical box, building(s), property corners or fixed survey marker). A minimum of two such reference points shall be noted on the site drawing. Site drawing(s) shall be based on a whole number scale not to exceed one (1) inch equals 100 feet. Acceptable scales are: 1 inch = 10, 20, 30, 40, 50, 60, 80 or 100 feet. Any site drawing exceeding the dimensions of 8.5 inches X 11 inches must be submitted in duplicate.5.2.1.5 Site drawings will show the location of all on-site and adjacent wells within 150 feet of the approved soils area. The following procedure shall be used in all cases when on-site or adjacent well(s) cannot be located. For instances where the on-site or adjacent well(s) are below ground and the homeowner or adjacent property owner states that the well is located in a certain area, this information shall suffice for verification of well location. Any well(s) that cannot be verified must be researched through the Water Supply Section of the Department. The search attempts to locate any well(s) that are near the affected parcel. If, after this search is completed, the well location(s) cannot be identified the Class D soil scientist can state "records were researched under this property owner's name and no information was found". The Department then sends a letter to the adjacent well owners notifying them of the need to locate their well(s) due to the future installation of an on-site wastewater treatment and disposal system. If no response is rendered within 15 days of receipt then the new system is to be designed to maximize the isolation distance from the property line.5.2.1.6 A site evaluation prescription shall follow an approach that includes consideration of topography, available area, slope gradient and uniformity, soil profile (thickness and depth of each horizon, color, percolation, absorption rate, redoximorphic features, texture (see Exhibit B), and zones of saturation), drinking water supplies, bodies of water, and shellfish growing areas. All suitable soils within the evaluated area shall be delineated regardless of isolation distances, physical encumbrances and easement requirements as well as any of the above conditions which may exist.5.2.1.7 All soil borings, holes and/or pits shall be flagged, identified and adequately shown on the site drawing.5.2.1.8 In describing the soils and soil profile, the Class D soil scientist shall adhere to the procedures and techniques provided in the Soil Survey Manual, USDA Agricultural Handbook No. 18 Keys to Soil Taxonomy and Field Book for Describing and Sampling Soils, as published by the U.S. Department of Agriculture.5.2.1.9 The report shall contain, at a minimum, observations of the following site characteristics, if present: 5.2.1.9.1 Parcel size, location map of project site, 12 digit Hydrologic Unit Code (HUC) watershed name, configuration and approximate dimensions.5.2.1.9.2 Slope - approximate percent and direction.5.2.1.9.3 Surface streams, springs or other bodies of water and their definition (e.g. shellfish, intermittent, ephemeral, etc.).5.2.1.9.4 Existing wells within 150 feet of approved soils area, measured from two (2) reference points or established survey control.5.2.1.9.6 Cuts and fills.5.2.1.9.7 Unstable landforms.5.2.1.9.8 A representative number of soil profile descriptions (minimum of three (3) soil borings or two (2) test pits per acre) and one soil profile description per design area in the evaluated area(s). These shall identify the soil series or taxonomic subgroup (e.g. Sassafras or Typic Hapludult). The geographic coordinates of each representative soil boring and/or test pit, a minimum of two (2), must be determined by a global positioning system.5.2.1.9.9 Zones of saturation (as indicated by redoximorphic features).5.2.1.9.10 Approved soils area(s) with extents delineated.5.2.1.9.12 Central wastewater or water systems availability.5.2.1.9.13 Location of any wetlands, refer to the 2007 Statewide Wetlands Mapping Project (SWMP) map, and State Tidal Wetlands maps, if applicable.5.2.1.9.14 Any overhead utilities.5.2.1.9.15 Existing buildings.5.2.1.9.16 Existing on-site and adjacent wastewater treatment and disposal systems.5.2.1.9.17 Flood prone areas designated as "V" zones by FEMA.5.2.1.9.18 Tax ditches with associated easements and right of ways.5.2.1.9.19 When prescribing a Wisconsin At-Grade system include the following information: 5.2.1.9.19.1 The percolation rate of the most limiting horizon within the upper 36 inches.5.2.1.9.19.2 The incremental loading rate (ILR) (see Exhibit V) of each horizon within the upper 20 inches.5.2.1.9.19.3 Provide this information in the "Design Considerations and Comments Section" of the approval page.5.2.1.10 The application/construction permit may be submitted with the site evaluation, in an emergency situation, when there is a public health risk associated with a malfunctioning system. The permit shall not be approved until the site evaluation is reviewed and complies with these Regulations. Site evaluations needed to replace the malfunctioning system shall be given a priority review.5.2.1.11 Once received, the report shall be reviewed for compliance with current Regulations by a DNREC Environmental Scientist with a soil science background. If the report is in non compliance, the Class D soil scientist shall be notified. The Class D soil scientist shall contact the Department and follow up with written correspondence to rectify the discrepancy. The Department shall not modify any site evaluation report unless requested by the Class D soil scientist. The corrections shall be submitted to the Department from the Class D soil scientist and a corrected copy to the owner/agent. The review process, which may include a field check, shall take place within 10 working days of receipt. NOTE: If approval cannot be issued within 10 working days, the property owner or authorized agent shall be notified of the delay and a tentative date of approval or denial shall be given. However, if no property owner or authorized agent contact number provided the Department will contact the Class D soil scientist. Once approved, the report shall be mailed to the property owner or his/her authorized agent. A percentage of randomly chosen site evaluations submitted shall be field verified by DNREC staff. Site evaluations' requiring test pits should be scheduled with the Department 72 hours prior to conducting the site evaluation.
5.2.1.12 Approval of a site evaluation indicates only that the site evaluation was conducted in compliance with these Regulations. It is not an indication of the correctness or quality of the site evaluation or an indication that a permit can be issued.5.2.1.13 The approved site evaluation report shall indicate the type of the initial and type of replacement system for which the site is approved.5.2.1.14 Technical regulation changes shall not invalidate an unexpired approved site evaluation but may require the use of a different type of system.5.2.1.15 The approved site evaluation shall be valid for five (5) years from the date of the Department's approval unless a subdivision base plan restricting well and on-site wastewater treatment and disposal system locations has been approved by the Department and recorded in the local Recorder of Deeds Office. After the five (5) year period, a current site evaluation as outlined in Section 5.2.1 shall be submitted to the Department for approval. This site evaluation will be reviewed as outlined in Sections 5.2.1.10 and 5.2.1.11 and must include at least one (1) new soil boring and profile description as well as any previous descriptions referred to in the approval page and report.5.2.1.16 Supplemental soil information submitted after the original site evaluation has been approved and, prior to expiring, shall include a revised approval page, report page, soil profile notes, and revised site drawing locating supplemental borings/test pits. In all cases, the new report shall be approved provided all criteria for approval are met. If the purpose of supplemental work is to change the type of system previously prescribed, another review fee shall be required. Likewise, any borings/test pits conducted greater than 100 feet from the previously approved area, with or without a system change, or lot reconfiguration shall require a review fee. On larger parcels, the area evaluated shall be delineated on the site drawing.5.2.1.17 The Department shall issue a notice of its intention to deny a site evaluation when appropriate.5.2.1.18 A property owner or agent has the option to use observation wells and/or piezometers to demonstrate that redoximorphic features are not an indication of a present day limiting zone. Section 5.2.3 provides procedures for the use of observation wells/piezometers to determine the depth and duration of zones of saturation.5.2.1.19 Site evaluations shall expire in accordance with Section 5.2.1.15 unless: 5.2.1.19.1 A subdivision base plan (record plat) restricting well and on-site wastewater treatment and disposal system (OWTDS) locations has been approved by the Department and then recorded with the Recorder of Deeds.5.2.1.19.1.1 Recordation and/or re-recordation of a minor subdivision or individual lots not in a major subdivision5.2.1.19.1.1.1 Applicant to submit to the Groundwater Discharges Section a Declaration of Covenants and Restrictions (DCR) with a surveyed site plan restricting the well and OWTDS locations along with the site evaluation. Once approved the applicant shall have the DCR and site plan recorded with the Recorder of Deeds.5.2.1.19.1.2 Re-recordation of lots within a major subdivision 5.2.1.19.1.2.1 If partial subdivision re-recordation is approved by local zoning authority restricting well and OWTDS locations, the Department will consider a new subdivision base plan (record plat) for the purposes of this regulation.5.2.1.19.1.3 Re-recordation of a major subdivision5.2.1.19.1.3.1 If a subdivision re-recordation is approved by local zoning authority restricting well and OWTDS location, the Department will consider a new subdivision base plan (record plat) for the purposes of this regulation.5.2.1.19.2 Installed Systems 5.2.1.19.2.1 Replacement/Malfunction (as defined in these Regulations)5.2.1.19.2.1.1 In the case of replacement/malfunction system; a new site evaluation performed by a Class D soil scientist is required if the site evaluation is over five (5) years old.5.2.1.19.2.1.1.1 If the site evaluation is less than five (5) years old; the Department strongly recommends that a supplemental soil boring be performed by a Class D soil scientist.5.2.1.19.2.2 Expansion/Upgrade 5.2.1.19.2.2.1 In the case of an expansion/upgrade system for which an approved site evaluation is on file, it is recommended that a supplemental soil boring(s) as per section 5.2.1.16 be performed by a Class D soil scientist.5.2.1.19.2.3 Emergency Repair/Repair 5.2.1.19.2.3.1 In the case of an application for a repair, the Department will review on a case by case basis the information supplied/extenuating circumstances to determine if supplemental borings or a new site evaluation is needed5.2.1.19.3 Any expired site evaluation that allowed a holding tank as an option and a new site evaluation and wet season monitoring (if applicable) confirms that it is a denied site; the Department will apply the Regulations that were in effect when the original site evaluation was denied.5.2.2 Soil Feasibility Study 5.2.2.1 It is the policy of the Department to facilitate compliance with these Regulations through review of proposed development projects as early as possible in the development process to avoid unnecessary conflicts and expense. Any development project, which may or may not constitute a major subdivision, can submit a feasibility study to satisfy other local government approval processes. Any project that proposes to use individual on site and/or large wastewater treatment and disposal systems must submit a letter of intent prior to initiating any preliminary soil investigations.5.2.2.2 The letter of intent must contain the following details: 5.2.2.2.1 The name of the developer and landowner.5.2.2.2.2 The size, tax map number, 12 digit Hydrologic Unit Code (HUC) watershed name, zoning certificate for and the location of the parcel.5.2.2.2.3 Number of proposed lots and/or projected flow rates.5.2.2.2.4 Projected start date of site/soil investigative work.5.2.2.2.5 Name of the Class D.2 or D.3 soil scientist and contact information5.2.2.3 If the proposed number of lots is >= 50 and >= 50% of the on-site soils have limiting zones < 48 inches or the number of lots is <= 100 or a large on-site wastewater treatment and disposal system (LOWTDS) is proposed, proceed to the requirements of Section 6.2, if not, proceed to Section 5.2.2.5. Prior to the submission of a SIR, the Class D soil scientist may submit a soil feasibility study in accordance with Section 5.2.2.4.5.2.2.4 A soil feasibility study for a LOWTDS shall contain the following information: 5.2.2.4.1 Site plan drawn to scale not to exceed one (1) inch equals 200 feet.5.2.2.4.2 Illustrate topography on one (1) foot contour intervals unless the Department approves the use of an alternate scale due to extreme variations in the elevation on the site.5.2.2.4.3 Conduct a soil suitability evaluation of the project site following the procedures prescribed in Section 5.2.1. The area of investigation should be concentrated within the proposed LOWTDS. The soil scientist must demonstrate the area proposed for the LOWTDS represents the best soils on the project site. The extent and nature of the soil evaluation shall be determined by the Class D soil scientist.5.2.2.4.4 Based on preliminary design criteria established by the Class D soil scientist, as a result of the soils evaluation, a preliminary engineering study prepared by a Class C designer must be included which demonstrates the suitability of the evaluated area for the proposed number of lots. The engineering study must include, at a minimum, the proposed method of disposal, proposed treatment levels, and proposed design flow rates, along with preliminary calculations/layout to demonstrate there is sufficient area for both the initial and replacement system.5.2.2.4.5 The Department may ask for any additional information deemed necessary to make a statement of feasibility.5.2.2.5 A soil feasibility study for individual OWTDS shall be filed with the Department setting forth the proposed manner of compliance with these Regulations. The soil feasibility study shall contain the following information: 5.2.2.5.1 Site plan must be drawn to scale not to exceed one (1) inch equals 200 feet.5.2.2.5.2 Illustrate topography by two (2) foot contour intervals unless the Department approves the use of an alternate scale due to extreme variations in elevation on the site.5.2.2.5.3 Illustrate the approximate location of all wells, watercourses, roads and on-site wastewater treatment and disposal systems within 150 feet of the perimeter of the property.5.2.2.5.4 Conduct a soil suitability evaluation of the project site following procedures prescribed in Section 5.2.1. The extent and nature of the soil evaluation shall be determined by a Class D soil scientist. The Class D soil scientist shall coordinate the planning of the soils evaluation with the Department prior to initiating work. The use of a 200 foot grid may help facilitate the evaluation.5.2.2.5.5 Indicate the type of limiting zone, its depth, and list the results of the site and soils analysis on the appropriate forms.5.2.2.5.6 Each soil interpretative unit identified for potential on-site wastewater treatment and disposal shall have at least one (1) set of percolation tests (minimum of 3) conducted within it to establish representative percolation rates for each interpretative unit.5.2.2.5.7 Lot numbers and approximate lot areas shall be provided.5.2.2.5.8 A general site location map shall be included on the preliminary plan for reference identification of the area.5.2.2.5.9 Proposed storm water management areas.5.2.2.5.10 Location of any wetlands, refer to the 2007 Statewide Wetlands Mapping Project (SWMP) map, and State Tidal Wetlands maps, if applicable.5.2.2.5.11 Any other information required by the Department.5.2.2.6 The Department shall conduct a general review of the preliminary plan and give the owner/developer a statement of preliminary subdivision feasibility which shall contain a statement of on-site wastewater treatment and disposal feasibility. This Section shall not be construed to relieve the applicant of the responsibility of obtaining individual site evaluations and permits from the Department for each lot prior to commencement of construction of any OWTDS.5.2.3 Observation Wells/Piezometers5.2.3.1 Observing water table fluctuations shall follow these procedures: 5.2.3.1.1 The property owner or authorized agent shall notify the Department, in writing, to "Request to use observation wells and/or piezometers" to determine the present day limiting zone which must include the following details:5.2.3.1.1.1 The name of the developer and/or property owner.5.2.3.1.1.2 The size, tax parcel number, zoning certificate for and location of the parcel.5.2.3.1.1.3 Contact information of the property owner and/or developer (address/phone).5.2.3.1.1.4 Names of the Class D soil scientist and person reading the wells, if different.5.2.3.1.1.5 Projected date of observation well/piezometer installation.5.2.3.1.1.6 Projected date of reading commencement.5.2.3.1.1.7 Reason for request.5.2.3.1.2 The Class D soil scientist shall provide the following information: 5.2.3.1.2.1 A minimum of three (3) logged soil profile notes for borings performed within the proposed monitoring area.5.2.3.1.2.2 Site evaluation report page summarizing soil/site conditions.5.2.3.1.2.3 Sketch showing observation well/piezometer locations.5.2.3.1.2.4 Appropriate fee.5.2.3.1.3 The Department shall review the submittals and provide comments/concerns, if any, regarding the proposed request and/or soils information.5.2.3.1.4 Observation wells and/or piezometers shall be installed by or under the direct on-site supervision of a well driller licensed by the State of Delaware in accordance with the current Regulations Governing the Construction and Use of Wells and Exhibit Z. It shall be the responsibility of the Class D soil scientist to determine the depth of installation with guidance provided by the Department, if solicited.5.2.3.1.5 The observation wells and/or piezometers must be installed prior to December 1st and monitoring will commence on this date as well. Monitoring will continue through May 15th of the following year as outlined below.5.2.3.1.6 Monitoring must be performed by Class A, B, C, D, E, F, H or I licensees or DNREC licensed well driller. Monitoring shall occur, at a minimum, weekly throughout the monitoring period. If water is observed above 18 inches for siting OWTDS, more frequent observations are warranted. For the purposes of siting an OWTDS via observation wells and/or piezometers the hydrologic limiting zone will be determined based on the average of all readings taken within a 14 consecutive day period during the wet season determined to represent the seasonal peak water table levels. 5.2.3.1.6.1 The Department shall field check the monitoring periodically during the time of expected saturated soil conditions at their discretion.5.2.3.1.6.2 The Department may, at any time during the observation period, verify the observed water depth by conducting a soil boring next to, and of equal depth with, any of the observation wells/piezometers. If the water level in the fresh boring, after 24 hours, presents a discrepancy with the water level observed in the well/piezometer, then at the discretion of the Department, the data may be declared invalid. If the data is declared invalid, then the Department will notify the owner in writing of the invalid data within 10 days of determination.5.2.3.1.7 It shall be the responsibility of the Department to evaluate if precipitation levels occurring during the monitoring period are sufficient for accepting data. If, in the estimation of the Department, insufficient precipitation was received, observation wells and/or piezometers may have to be monitored an additional wet season. A near normal monitoring period is defined as a period that has plus or minus one standard deviation of the long term mean annual precipitation. (Long term refers to 30 or more years). Also, the mean monthly precipitation during a normal period must be plus or minus one standard deviation of the long term monthly precipitation for 8 of the 12 months. For the most part, normal years can be calculated from the mean annual precipitation.5.2.3.1.8 Should the precipitation and long-term groundwater levels be significantly below or above normal, a mathematical analysis may be utilized under the direction of the Department to correlate present data with past years. The methodology and validity of such analysis is at the sole discretion of the Department.5.2.3.1.9 When monitoring determines that the site is suitable, the Department will request a complete site evaluation be submitted in compliance with these Regulations prior to August 15th to be reviewed. The monitoring information must be incorporated into the new site evaluation. An approved site evaluation report shall be issued indicating the appropriate system type(s) and both, the site evaluation and monitoring data, will expire five (5) years from date of approval if not permitted.5.2.3.1.10 Observation wells and/or piezometers are required to be abandoned in accordance with the current Regulations Governing the Construction and Use of Wells.5.2.4 Soil Percolation Rate Determination 5.2.4.1 Percolation rates are assigned by State Environmental Scientists and Class D soil scientists based upon observed soil structure and textures during the site evaluation. The Department has established a table of percolation rates based upon USDA soil textures (see Exhibit Y).5.2.4.2 Soil Percolation Test 5.2.4.2.1 The soil percolation test shall provide a measure of the rate at which water moves from an uncased bore hole into the surrounding soil under nearly constant head in both vertical and horizontal directions.5.2.4.2.2 One (1) soil percolation test shall consist of three (3) test holes.5.2.4.2.3 The percolation test shall be performed only after a site evaluation has indicated that the soil may be suitable for an on site wastewater treatment and disposal system. The percolation test shall be used to determine the rate at which wastewater effluent can be expected to seep into the soil. This rate shall be used in conjunction with a projected daily flow rate to determine the area required for proper treatment and disposal.5.2.4.2.4 The depth of the percolation test holes shall not be determined until a site evaluation is completed and a limiting zone, if any, is identified. The depth of the percolation test holes shall be as follows: 5.2.4.2.4.1 If the limiting zone occurs at least 20 inches from the soil surface, the percolation test holes shall be within the soil horizon controlling the water movement vertically and/or horizontally to a depth of 60 inches.5.2.4.2.4.2 If the limiting zone occurs at less than 20 inches from the surface, the site is unsuitable for a conventional on site wastewater treatment and disposal system. However, if replacing a failing or malfunctioning system, Section 5.2.4.2.4.1 should be used without regard for the 20 inch limiting condition. In situations where sand-lining through an impermeable or less permeable horizon within the top 48 inches, a percolation test should be performed within the soil zone which is controlling the water movement vertically and/or horizontally beneath the restrictive material to a depth of 60 inches.5.2.4.2.5 The following procedures shall be used for percolation tests:5.2.4.2.5.1 A minimum of three (3) test holes shall be dug within the proposed installation area of the absorption facility. Additional tests may be required in areas with varying soil characteristics or when warranted at the sole discretion of the Department due to the size of the required disposal area.5.2.4.2.5.2 Test holes with a horizontal diameter of six (6) inches shall be dug or bored. A post hole digger, auger or mechanical digger may be used to dig the holes.5.2.4.2.5.3 The bottom and sides of each test hole shall be scarified to remove any smeared soil surfaces that result from digging. Loose soil shall be removed from the hole. Two (2) inches of coarse sand or fine aggregate shall be placed in the bottom of the hole to prevent sealing of the hole bottom when water is added.5.2.4.2.5.4 The hole shall be filled with water to a minimum depth of 12 inches above the aggregate or sand. This level shall be maintained for a period of at least four (4) hours.5.2.4.2.5.5 The water level shall then be adjusted to six (6) inches over the gravel or sand. The hole shall be allowed to stand undisturbed for 30 minutes. The water level shall again be adjusted to six (6) inches over the aggregate and the hole allowed to infiltrate undisturbed for another 30 minutes.5.2.4.2.5.6 Where the drop in the water level is two (2) inches or more in 30 minutes, the interval for readings during the percolation test shall be 10 minutes. Where the drop in the water level is less than two (2) inches in 30 minutes, the interval for readings during the percolation test shall be 30 minutes. The drop in water level shall be recorded after each reading and the water level shall be adjusted to six (6) inches above the gravel. Readings shall continue for a minimum of four (4) hours where the interval between readings is 30 minutes. Where the interval is 10 minutes due to fast percolation, the readings may be discontinued after one (1) hour. Where the drop between readings has not stabilized at the end of the minimum period, the reading shall continue until a steady rate is established. A steady rate is established when two (2) successive water level drops do not vary by more than one-sixteenth (1/16) of an inch. If any of the holes has a rate that is significantly different from the other holes, it shall be examined to see if this hole is in a soil that is different from the soil described in the site evaluation. If the hole is determined, by the licensed percolation tester, to be uncharacteristic of the site it shall be excluded from analysis but listed on the application.5.2.4.2.5.7 The percolation rate for the site shall be determined by taking the arithmetic average of all percolation tests conducted. Percolation rates slower than 120 minutes per inch (mpi) are unacceptable and shall not be used to determine the arithmetic average percolation rate but shall be reported. On site wastewater treatment and disposal systems shall not be placed on those portions of any sites that have percolation rates slower than 120 mpi.5.2.4.3 Additional Methodologies At the discretion of the Department or Class D soil scientist, additional methodologies may be preferred as a substitute for the soil percolation test. Approved test methods are given in the current edition of Methods of Soil Analysis, ASA and the ASTM Standards.
5.2.5 Site Interpretation Advisory Council 5.2.5.1 The purpose of the Site Interpretation Advisory Council (Council) is to act as an objective peer group in the review of discrepancies between the Department and Class D soil scientists regarding questions of interpretation of soil and site information for the purpose of siting on site wastewater treatment and disposal systems.5.2.5.2 The Council shall restrict its charge to those items normally and commonly addressed when conducting a site evaluation as discussed below. The Council specifically excludes instances regarding the engineering design and/or installation of on-site wastewater treatment and disposal systems except when it is directly applied to the soil science practice. 5.2.5.2.1 The description and interpretation of soil morphology in regard to the proper functioning of on site wastewater treatment and disposal systems utilizing the soil as part of the treatment process.5.2.5.2.2 The characterization of lithologic and hydrologic limiting layers and geomorphology pertinent to the proper siting and functioning of on-site wastewater treatment and disposal systems.5.2.5.2.3 The recognition and documentation of site limitations for the placement of on site wastewater treatment and disposal systems (e.g. existing wells and on-site wastewater treatment and disposal systems) in accordance with standard practice in Delaware.5.2.5.3 The Council shall be appointed by the Secretary and consist of the following members: 5.2.5.3.1 Four (4) non governmental Class D.2 or D.3 soil scientists actively practicing in the State of Delaware for two (2) or more years with one (1) acting as an alternate.5.2.5.3.2 One (1) employee of the Department with soils and on site wastewater industry expertise.5.2.5.3.3 One (1) soil scientist designated by the State Conservationist through the State Soil Scientist, NRCS, USDA.5.2.5.3.4 A manager of the Groundwater Discharges Section (GDS), DNREC, shall serve as a liaison to the Council without voting privileges.5.2.5.3.5 All members shall serve three (3) year terms. Procedures shall be established by the Council to stagger terms so as to provide continuity.5.2.5.4 Documentation and testimony regarding a review shall be submitted to the Council. After the initial review by the Council, a determination shall be made as to whether sufficient information has been submitted to render an informed decision. The Council may request additional information from the applicant before proceeding with the review. There shall be no cost to the Council for any information submitted.5.2.5.5 Within 30 days from receipt of the documentation, the Council shall render a decision, based on a simple majority vote, regarding which system(s), if any, are suitable under the Delaware Regulations.5.2.5.6 A site visit shall be conducted by at least two (2) members of the Council. The applicant is responsible for all costs that may be incurred. Council members shall not be reimbursed for any expenses.5.2.5.7 Any decision rendered by the Council shall be considered by the Secretary and may be a deciding factor in his/her decision. The applicant still maintains his/her right to appeal the decision of the Secretary in accordance with7Del.C.§ 6008.5.2.5.8 The Council shall designate one of its members representing the private sector to serve as chairperson for a period of one year. The chairperson, or his/her designee, serving as the principal contact person between the Council and a manager of the Groundwater Discharges Section (GDS), shall perform the following duties: 5.2.5.8.1 Call and preside at all Council meetings. (A GDS manager may also call a meeting, but is not entitled to preside at a Council meeting.)5.2.5.8.2 Upon receipt of a request, poll the Council members and communicate the results to the GDS manager calling a Council meeting when appropriate. (This function may also be performed by the GDS manager, when necessary.)5.2.5.8.3 Prepare a letter communicating the Council's decision in each case. (The letter shall be sent within 15 working days after the Council's decision to the GDS manager for signature and returned for mailing within three (3) working days.)5.2.5.9 The following services shall be furnished by the DNREC to facilitate the operation of this Council: 5.2.5.9.1 A manager of the Groundwater Discharges Section shall represent the Section's position at all Council meetings.5.2.5.9.2 All submittals for consideration shall be circulated to the Council under the direction of the GDS manager within 10 working days.5.2.5.9.3 A GDS manager, at the request of the Council chairperson, shall reserve space in the DNREC facilities for Council meetings.5.2.5.9.4 The DNREC shall provide clerical services for record keeping. Records of the Council meetings shall be furnished to all Council members within 15 working days following the meetings.5.2.5.9.5 The clerical person shall prepare and mail the decisions of the Council upon receipt from the chairperson.5.2.5.10 The Council shall restrict reviews to those submittals using one of the following two (2) methods:5.2.5.10.1 A submittal from the Secretary, DNREC; or5.2.5.10.2 A submittal from a Class D soil scientist.5.2.5.11 All submittals shall be circulated to the Council membership. A majority vote of the Council is required for any submittal to be accepted for Council review.5.3 Permitting 5.3.1 General Requirements 5.3.1.1 No person shall cause or allow construction, or repair of a system, or any part thereof, without a permit. An exception may be allowed for certain emergency repairs as set forth in these Regulations.5.3.1.2 All disposal systems shall be located according to the minimum horizontal isolation distances specified in these Regulations (see Exhibit W). All isolation distances for capped systems and elevated sand mounds shall be measured from the edge of the aggregate or aggregate-free chamber.5.3.1.3 All pressurized systems must be constructed in such a manner that the operating pressure can be checked at the end of the distal lateral (permanent tee, etc).5.3.1.4 All pressurized systems must utilize timers or other electrical on/off delay devices to ensure dosing frequencies. Timers must be part of the control panel. Any timer system utilizing a demand over-ride float shall incorporate a pump cycle counter and elapsed time meter.5.3.1.5 Trench depths as prescribed in the approved site evaluation are for the upslope side of the trench only. Trench systems designed in sloping disposal areas > 5% may result in downslope trench sidewall depths that may change system type (e.g. capping fill vice full depth).5.3.2 Disposal System Sizing 5.3.2.1 All disposal systems shall be sized based on the estimated wastewater flow and the results of percolation tests or the assigned percolation rate. Percolation rates shall be based on USDA soil textures and assigned by the Class D soil scientist. The table of percolation rates used by the Department (see Exhibit Y) does not represent assigned rates, but instead gives estimates based upon textures. Percolation rates < 20 minutes per inch (mpi) will not be allowed for designing any on-site wastewater treatment and disposal system, unless otherwise approved by the Department.5.3.2.2 The minimum disposal area required for trench systems with percolation rates <= 120 mpi shall be determined from the following equation: A = 0.33 Q (t)0.5
Where:
A = the minimum disposal area required in square feet
Q = wastewater application rate in gallons per day
t = the average percolation rate in minutes per inch (minimum rate is 20 mpi for design)
5.3.2.3 The minimum disposal area required for seepage bed systems with percolation rates <= 120 mpi shall be determined from the following equation: A = 0.42 Q (t)0.5
Where:
A = the minimum disposal area required in square feet
Q = wastewater application rate in gallons per day
t = the average percolation rate in minutes per inch (minimum rate is 20 mpi for design)
5.3.2.4 Where percolation rates are < 6 mpi (minimum rate is 20 mpi for design), such as in soils with USDA textures of sands, and loamy sands, a pressurized distribution system is required; the minimum disposal area shall be determined from the following equation: A = 1.2 Q
Where:
A = the minimum disposal area required in square feet
Q = design flow rate in gallons per day
5.3.2.5 The minimum disposal area required for low-pressure pipe systems with percolation rates <= 120 mpi (minimum rate is 20 mpi for design) shall be determined from the following equation: A = UQ
Where:
A = the minimum disposal are required in square feet
Q = design flow rate in gallons per day
U = unit absorption area (see Exhibit P)
5.3.2.6 The minimum disposal area for Wisconsin At-Grade systems with percolation rates <= 75 mpi (minimum rate is 20 mpi for design) shall be determined from the following criteria: 5.3.2.6.1 Calculate the long term acceptance rate (LTAR) (see Exhibit V); and5.3.2.6.2 Calculate the horizontal acceptance rate (HAR) in gpd/ft using the following equation: HAR = sum (incremental loading rate (in site evaluation) (see Exhibit V)) X (thickness of each horizon (inches) to a depth of 20 inches)
5.3.2.6.3 Calculate the effective absorption area (EAA) in ft2 using the following equation: EAA = Q/LTAR
Where:
Q = design flow rate in gallons per day
LTAR = long term acceptance rate (see Section 5.3.2.6.1)
5.3.2.6.4 Calculate the effective absorption width (EAW) in feet using the following equation: EAW = HAR/(1.2 - LTAR)
Where:
HAR = horizontal acceptance rate (see Section 5.3.2.6.2)
LTAR = long term acceptance rate (see Section 5.3.2.6.1)
NOTE: An effective width of four (4) to nine (9) feet is appropriate. The designer should use an EAW that is <= the calculated value. If the calculated value is > 10 feet then limit the EAW to 10 feet.
5.3.2.6.5 Calculate the absorption length (AL) in feet using the following equation: AL = EAA/EAW
5.3.2.7 For design criteria and requirements for the permitting of micro-irrigation (drip) or peat biofilter systems refer to the specific Department guidelines located at the end of the Regulations.5.3.3 Wastewater Design Flow Rates 5.3.3.1 The projected peak daily wastewater flow shall be used to determine the appropriate size and design of on site wastewater treatment and disposal systems.5.3.3.2 Where actual calibrated metered flow data indicating peak daily flows over the most recent three (3) year period are available for a similar facility, such peak flow data may be substituted for the wastewater flows listed in this section subject to the approval of the Department. When ranked in descending order the adjusted design daily flow shall be determined by taking the numerical average of the daily readings within the upper 10% of the daily readings.5.3.3.3 The design wastewater flow from residential dwellings, including single family, multiple family, manufactured homes, and apartments served by on site wastewater treatment and disposal systems shall be 120 gallons per day per bedroom. The minimum design flow for any commercial property shall be 120 gallons per day and residential dwellings shall be 240 gallons per day. Credit for water conservation devices will be accounted for according to current Department guidelines.5.3.3.4 The design wastewater flow from other residential, commercial and/or institutional facilities served by on site systems shall be as prescribed in Exhibit D.5.3.3.5 Disposal systems shall be designed to receive all wastewater, except for water softener backwash (regeneration water), from the building or structure served unless otherwise approved by the Department.5.3.3.6 All restaurants or other establishments involved in food preparation activities shall install external grease traps as required by the Department.5.3.3.7 Laundromat and car wash wastewater shall be pretreated as specified by the Department prior to discharge to any absorption facility under these Regulations.5.3.3.8 Industrial wastewater shall not be discharged into a septic tank unless prior approval is obtained from the Department.5.3.4 Isolation Distances5.3.4.1 The minimum isolation distances set forth in Exhibit C shall be maintained when designing, locating, repairing, replacing, and installing on site wastewater treatment and disposal systems.5.3.4.2 The Department may require greater isolation distances for systems when conditions warrant for purposes of protecting environmental resources and the public health.5.3.4.3 Isolation distances may be decreased by the Department based on a site specific geological and hydrogeological analysis performed pursuant to the requirements of these Regulations, provided that the Department is satisfied that such decrease will allow for protection of environmental resources and the public health.5.3.4.4 Existing on site wastewater treatment and disposal systems which are repaired or replaced shall be subject to the requirements of this Section, provided however, that if it is impossible to comply with such requirements due to lot size limitations, the repaired or replaced system shall conform to the maximum extent practicable with the requirements of this Section as determined by the Department at its sole discretion.5.3.5 Water Conservation Devices5.3.5.1 A 25% reduction in design flow is allowed for water conservation. The absorption facility shall be enlarged if the conservation devices are removed, become inoperative, or the system malfunctions.5.3.5.2 Water saving plumbing devices are encouraged to lengthen the life of the absorption facility. However, only permanent water saving plumbing devices such as low flush toilets shall be considered in reducing the size of the absorption facility for replacement systems with limited approved disposal area, properties located in a five (5) year plan sewer district or temporary structure. Devices such as inserts in showers are considered temporary. Water conservation reductions of 25% in design flows will not be permissible for new construction.5.3.6 Dosing and Diversion Systems 5.3.6.1 Effluent from on site wastewater treatment and disposal systems shall be transmitted to the absorption facility by gravity, pressure distribution systems utilizing a dosing chamber (see Exhibit I) or lifted by a lift station (see Exhibit X) to overcome elevational differences between the septic tank and the gravity absorption facility.5.3.6.2 Gravity distribution systems may be used when the design wastewater flow requires < 2,500 ft2 of disposal area for seepage trenches or seepage beds and the percolation rate is >= six (6) minutes per inch.5.3.7 Gravity distribution systems shall conform to the following requirements: 5.3.7.1 All unperforated gravity transmission pipe up to the distribution box shall be Sch. 40 PVC at least four (4) inches or greater in diameter unless lifted by a lift station to a distribution box in which case a minimum 11/2 inch diameter pipe would be permissible with a minimum of 20 feet of four (4) inch diameter Sch. 40 PVC pipe set at a minimum grade of 1/8 inch per foot prior to entering the distribution box. NOTE: Minimum bury depth requirements apply to all pressurized transmission piping - see Section 5.3.9.2.
5.3.7.2 All gravity transmission piping shall be placed on a firm undisturbed or well compacted soil. All joints shall be watertight. A minimum grade of 1/8 inch per foot shall be provided for gravity transmission piping. Clean backfill shall be placed around and over the pipe and hand tamped to provide compaction.5.3.7.3 All gravity distribution laterals shall be thin walled or Sch. 40 PVC and shall be four (4) inches in diameter. Perforated PVC pipe shall have 3/8 to 3/4 inch diameter holes a maximum of 30 inches on center. Coiled and corrugated piping shall not be used. A grade of less than two (2) inches per 100 feet shall be provided for all gravity distribution laterals.5.3.7.4 The design and construction of the gravity distribution system shall provide uniform application of the effluent. All distribution laterals shall be of equal length unless approved by the Department. The effluent shall be equally divided between laterals of the gravity distribution system by means of a distribution box.5.3.7.5 Stepped trenches shall be used on sloping ground.5.3.7.6 All distribution boxes shall conform to the following requirements (see Exhibit H): 5.3.7.6.1 Location: Distribution boxes shall be used with all gravity systems. They shall be located in accordance with the minimum horizontal isolation distances set forth in Exhibit C. A minimum distance of three (3) feet shall separate the inlet face of the distribution box from the septic tank outlet.5.3.7.6.2 Capacity: Distribution boxes shall be sized to accommodate the number of distribution laterals required for the distribution system.5.3.7.6.3 An inlet baffle shall be installed in all distribution boxes. The baffle shall be perpendicular to the inlet pipe and situated six (6) inches from the end of the inlet. The baffle shall be constructed of the same material as the distribution box. In cases where concrete distribution boxes are utilized, there shall be a 12 inch square rising from the box floor, centered with the inlet connection, and permanently affixed. In cases where plastic distribution boxes are utilized, PVC tees or 90° elbows may be incorporated as baffles.5.3.7.6.4 The inverts of all outlets shall be of the same elevation and at least one (1) inch below the inlet invert.5.3.7.6.5 Each inlet pipe and outlet distribution lateral shall be connected separately to the distribution box. Unperforated distribution piping shall be Sch. 40 PVC and extend a minimum of five (5) feet from the distribution box prior to the absorption facility.5.3.7.6.6 The requirements of Sections 5.3.14.6, 5.3.14.8 and 5.3.14.13 shall apply to all distribution boxes approved in accordance with these Regulations.5.3.7.6.7 Distribution boxes shall be accessible either by means of a removable cover or access riser and shall extend above grade at time of installation. The riser and lid shall be made of concrete or an equivalent durable material approved by the Department. If multiple risers are needed manufacturer recommendations must be followed. All above finished grade access covers shall be watertight and secure from vandalism.5.3.7.6.8 All installations of distribution boxes shall be in accordance with the requirements of Section 5.4.3.5.3.7.6.9 All installed distribution boxes shall be tested to ensure watertight conditions and leveled to ensure an even distribution of flow to each lateral under operating conditions.5.3.7.7 All systems utilizing a lift station must incorporate a float activated pump control panel. The control panel shall meet the requirements of Sections 5.3.17.13, 5.3.17.14 and 5.3.17.15.5.3.8 Pressure distribution systems shall be utilized with: 5.3.8.1 Trench or bed systems receiving flows requiring >= 2,500 ft2 of disposal area.5.3.8.3 Certain sand lined systems.5.3.8.4 All absorption facilities located on soils where percolation rates are < six (6) minutes per inch.5.3.8.5 All low pressure pipe systems.5.3.8.6 All Wisconsin at-grade systems.5.3.9 Pressure distribution systems shall conform to the following requirements: 5.3.9.1 All unperforated pressure transmission pipes shall be Sch. 40 PVC pipe unless approved by the Department. The pipe shall be sized to provide a minimum flow rate of two (2) feet per second in the pipe.5.3.9.2 All pressure transmission pipes shall be placed below the frost line. All joints shall be watertight and all pipes shall be placed on a firm undisturbed or well compacted soil. Clean backfill shall be placed around and over the pipe and hand tamped to provide compaction. Frost line minimums for each county are as follows: Sussex - 24 inches Kent - 24 inches New Castle - 30 inches
5.3.9.3 All pressure distribution laterals shall be Sch. 40 PVC pipe with diameters as determined by a Class C designer. Minimum hole diameters for perforated pressure distribution laterals shall be 5/32 to 1/2 inch maximum and spacing intervals as determined by a Class C designer and be placed on center along the length of the pipe. Maximum hole spacing shall be determined by percolation rates as follows: | Percolation Rate | Maximum Hole Spacing |
| 20 - 25 MPI | 60 inches |
| 30 - 60 MPI | 72 inches |
| 65 - 120 MPI | 96 inches |
NOTE: Trench systems designed on slopes > 5% must provide for balanced trench loading rates (gpd/ft2).
5.3.9.4 All laterals shall be connected to manifolds with tees or sanitary tees constructed of PVC corresponding to the size of the connecting laterals.5.3.9.5 Distribution of effluent from the pressure transmission pipe to the distribution laterals shall be by a central PVC manifold.5.3.9.6 The dose volume shall be designed so that the estimated daily flow shall be discharged to the absorption facility in a minimum of three (3) equal doses that either meets or exceeds minimum dose volume requirements. Minimum dose volume shall be five (5) times the internal (liquid) volume of all piping not flooded.5.3.9.7 The size of the dosing pumps shall be selected to maintain a minimum pressure of one (1) psi (2.31 feet of head) at the end of each distribution line. Pump characteristics and head calculations that include maximum static lift, pipe friction and orifice head requirements shall be submitted with permit applications.5.3.10 Diversion Boxes and Diversion Valves 5.3.10.1 Location: Diversion boxes or diversion valves for dual systems shall be located according to the requirements set forth in Exhibit C.5.3.10.2 Capacity: Diversion boxes and valves shall be sized to accommodate the piping connected to them.5.3.10.3 Diversion Valves: All pressure dosed dual systems shall use diversion valves.5.3.10.4 All installations shall be in accordance with the requirements of Section 5.4.3.5.3.10.5 Diversion boxes shall be pre-cast concrete or other approved products. Diversion valve systems shall be commercially available and diversion or gate valves shall be constructed of durable cast iron or plastic.5.3.11 Diversion Box and Diversion Valve Specifications (see Exhibit J):5.3.11.1 All diversion boxes and diversion valves shall be installed level with connecting piping to minimize stress.5.3.11.2 Cast iron valves shall be free of dirt and rust. Plastic valves shall be clean and dry before installation.5.3.11.3 Diversion boxes may be standard distribution boxes with selective flow diversion devices.5.3.11.4 All inlet and outlet cutout connections shall be sealed watertight with grout or approved rubber gaskets.5.3.11.5 Appurtenances: All buried valves shall be furnished with a suitable box constructed of durable material approved by the Department and extended to finished grade with a tight fitting secure access cover.5.3.11.6 Testing: Installed valves and gates shall be tested in the field prior to back fill.5.3.12 Conventional On-Site Wastewater Treatment and Disposal Systems Criteria 5.3.12.1 All Full Depth Gravity and Capping Fill Gravity Trench and Bed Treatment and Disposal Systems shall be designed in accordance with the following criteria (see Exhibits K, L, M or N). 5.3.12.1.1 Landscape Position: Areas with good surface drainage which allow surface water to run off easily without ponding and which are not prone to flooding.5.3.12.1.2 Slope: 0 - 15%: Bed systems cannot be sited on slopes > 2%, unless otherwise approved by the Department. All systems must be constructed with level bottoms and shall incorporate construction procedures prohibiting equipment from entering the excavation. Trench systems on slopes in excess of 15% shall be permitted only if the design is prepared by a licensed Class C designer. Any such design shall incorporate construction procedures.5.3.12.1.3 Depth to Limiting Zone: The limiting zone shall be a minimum of three (3) feet below the bottom of the trench >= 48 inches beneath the soil surface.5.3.12.1.4 Percolation Rates: 5.3.12.1.4.1 6 - 120 mpi: Gravity distribution systems may be allowed unless otherwise required by these Regulations. Construction of seepage trenches and beds in soils with percolation rates > 120 mpi shall not be permitted.5.3.12.1.4.2 < 6 mpi: A pressurized distribution system is required for seepage trenches or beds. The trench or bed may be placed between 12 and 24 inches in order to maintain 36 inch separation distance between rapidly permeable material and the limiting zone.5.3.12.2 All Low Pressure Pipe Treatment and Disposal Systems shall be designed in accordance with the following criteria (see Exhibits O & P). 5.3.12.2.1 Landscape Position: Areas with good surface drainage which allow surface water to run off easily without ponding and are not prone to flooding. Low pressure pipe (LPP) treatment and disposal systems shall not be prescribed in coastal beach sands.5.3.12.2.2 The depth to the bottom excavation shall be nine (9) inches to 18 inches. Trench width shall be 12 inches unless otherwise approved by the Department.5.3.12.2.3 Depth to Limiting Zone: The limiting zone shall be a minimum of 18 inches below the bottom of the trench (e.g. a minimum of 27 inches below existing grade for a nine (9) inch deep LPP trench system). Shallow disposal trenches (placed not less than nine (9) inches into the original soil profile) may be used with a capping fill to achieve the minimum separation distance specified above. The capping fill, if required, shall be placed in accordance with these Regulations (see Exhibit O). A capping fill cover is required for all LPP treatment and disposal systems with trench depths less than 18 inches.5.3.12.2.4 Earthen dams shall be designed at the beginning of each trench and subsequent dams spaced at a maximum of 20 feet thereafter.5.3.12.2.5 Lateral lines of the LPP treatment and disposal system which are placed on lower landscape positions shall have an interceptor drain installed upslope of the uppermost lateral to intercept and divert surface and subsurface waters away from the absorption facility as determined by a Class D licensee.5.3.12.2.6 There shall be no soil disturbance to the proposed disposal area except the minimum required for installation. The soils may be rendered unsuitable should unnecessary soil disturbance occur. Particular care should be taken when clearing wooded lots so as not to remove the surface soil material (see Lot Clearing Guidelines).5.3.12.2.7 LPP treatment and disposal systems shall be installed only with equipment approved by DNREC.5.3.12.2.8 LPP treatment and disposal systems shall not be allowed where sand lining is required or where soils have been filled or disturbed.5.3.12.2.9 Percolation Rate: 0 - 120 mpi: Construction on soils with percolation rates > 120 mpi is not permitted. A pressurized distribution system is required in all cases.5.3.12.3 All Wisconsin At-Grade Treatment and Disposal Systems shall be designed in accordance with the following criteria (see Exhibit U & V). 5.3.12.3.1 Landscape Position: Areas with good surface drainage which allow surface water to run off easily without ponding and are not prone to flooding. They shall not be prescribed in coastal beach sands due to the high probability of wind/water erosion and short effluent retention time in the coarse sands.5.3.12.3.2 Slope: 0 - 3% for soils with percolation rates faster than 75 mpi, unless otherwise approved by the Department.5.3.12.3.3 Depth to Limiting Zone: <= 24 inches to evidence of a limiting zone. Replacement systems must have a limiting zone <= 20 inches and in soils without an umbric epipedon or prone to ponding and/or flooding. Class D soil scientist shall verify these site characteristics are applicable prior to prescribing the Wisconsin at-grade as a disposal option. The soil scientist must also specify the percolation rate for each soil horizon to a depth of 36 inches and the incremental loading rates for the first 20 inches of soil (see Exhibit V).5.3.12.3.4 Percolation Rate: 0 - 75 mpi: Construction on soils with percolation rates > 75 mpi is not permitted. A pressurized distribution system is required in all cases.5.3.12.4 All Elevated Sand Mound Treatment and Disposal Systems shall be designed in accordance with the following criteria (see Exhibit Q). 5.3.12.4.1 Landscape Position: Areas with good surface drainage which allow surface water to run off easily without ponding and are not prone to flooding.5.3.12.4.2 Slope: 5.3.12.4.2.1 0 - 6% for soils with percolation rates slower than 60 mpi.5.3.12.4.2.2 0 - 12% for soils with percolation rates faster than 60 mpi.5.3.12.4.3 Depth to Limiting Zone: > 20 inches to evidence of a limiting zone.5.3.12.4.4 Percolation Rate: 0 - 120 mpi: Construction on soils with percolation rates > 120 mpi is not permitted. A pressurized distribution system is required in all cases.5.3.12.5 All Pressure-Dosed Full Depth and Capping Fill Treatment and Disposal Systems shall be designed in accordance with the following criteria except LPP systems (see Exhibits R & S). 5.3.12.5.1 Landscape Position: Areas with good surface drainage which allow surface water to run off easily without ponding and are not prone to flooding.5.3.12.5.2 Slope: 0 - 15%. Bed systems cannot be sited on slopes > 2%, unless otherwise approved by the Department. All designs must be constructed with level bottoms and shall prohibit equipment from entering the excavation. Slopes in excess of 15% shall incorporate construction procedures such as, but not limited to, equipment to be used, installation methods (e.g. trenches on contour, one trench at a time), and proper site restoration.5.3.12.5.3 Depth to Limiting Zone: >= 48 inches from original grade and three (3) feet below bottom of filter aggregate (e.g. a minimum of five (5) feet below existing grade for two (2) foot deep trench and bed systems).5.3.12.5.4 Percolation Rate: 0 - 120 mpi. Construction on soils with percolation rates > 120 mpi is not permitted. A pressurized distribution system is required in all cases.5.3.12.6 All Sand-lined Treatment and Disposal Systems shall be designed in accordance with the following criteria (see Exhibit T). 5.3.12.6.1 Landscape Position: Areas with good surface drainage which allow surface water to run off easily without ponding and are not prone to flooding.5.3.12.6.2 Slope: 0 - 15%. Slopes in excess of 15% shall only be allowed if the design is prepared by a Class C designer. Any such design shall incorporate construction procedures.5.3.12.6.3 Depth to Limiting Zone: >= 48 inches from original grade and three (3) feet below bottom of filter aggregate (except for impermeable, slowly permeable, or very slowly permeable materials proposed for removal). Sand-lined systems shall not be used where there is less than one (1) foot of undisturbed native soil between the limiting zone after excavation and the impermeable or slowly permeable soil zone. Sand-lining will not be permitted into the water table, except in instances where it is necessary for replacement systems to function hydraulically.5.3.12.6.4 Percolation Rate: 0 - 120 mpi. A pressurized distribution system may be required. The percolation test shall be taken in the permeable soil below the impermeable or less permeable soil zone. The bottom of the percolation test hole shall extend a minimum of six (6) inches below the slowly permeable soil zone but in no case shall it be < six (6) inches above the underlying limiting zone. If the percolation tests are to be conducted at a depth too deep to obtain accurate percolation rates, a percolation rate based on USDA soil textures shall be assigned (see Exhibit W). Otherwise, hydraulic conductivity tests may be substituted.5.3.12.6.5 Sand-lined systems may be used where the site evaluation has shown that there is an impermeable, slowly, or very slowly permeable soil zone located over an acceptable soil. Use of this system requires removal of that zone within the disposal area and its replacement with a sandy fill as prescribed under Section 5.4.2.1. The system shall be constructed in accordance with specifications for sand-lined seepage trenches and beds (see Exhibit S). Installation may require a Class D soil scientist on site to monitor depth of sand lining and proper interfacing of the sandy fill with the native soils.5.3.12.7 Artificially Drained Systems Disposal systems shall not be constructed on sites where curtain drains, vertical drains, under drains, or similar drainage methods are utilized to artificially lower the level of the water table to meet the requirements of these Regulations. Observation wells may be used to demonstrate the change in the hydrology of a particular property for the purpose of siting an on-site wastewater treatment and disposal system.
5.3.13 Building Sewers 5.3.13.1 The minimum requirements contained in this Section shall apply to all conduits, pipes or sewers which transmit wastewater flows from building or house drains to a septic tank (or other treatment device) and from the septic tank (or other treatment device) to the distribution box, lift station or dosing tank. Collection systems servicing three (3) or more units shall be in conformance with National Standards.5.3.13.2 Building sewers shall comply with the following requirements: 5.3.13.2.1 Location: A minimum horizontal separation of 10 feet shall be provided between a house or building sewer and any water line. Suction lines from wells shall not cross under house or building sewers.5.3.13.2.2 Size: Building sewers shall be sized to serve the expected flow from the connected fixtures. All building gravity sewer plumbing shall be at least as large as the internal building plumbing but in no case less than three (3) inches in diameter. Pressure building sewers transmitting wastewater to a septic tank (or other device) shall be a minimum of two (2) inches in diameter.5.3.13.2.3 Foundation: All building sewers shall be laid on a firm compacted bed through its entire length. Building sewers placed in wet soil shall have a four (4) inch bedding of 3/4" to 11/2" aggregate.5.3.13.2.4 Materials: Building sewers shall be constructed of Sch. 40 or Sch. 80 PVC, reinforced concrete, or Sch. 40 or Sch. 80 ABS pipe. PVC pipe encased in six (6) inches of concrete or sleeved within a larger sized Sch. 40 or Sch. 80 pipe shall be used for building sewers located < three (3) feet below driveways, parking area, or other areas subject to vehicular traffic or similar loading. The sleeving or encasement shall extend a minimum of two (2) feet beyond the edge of driveways, parking areas, or other areas subject to vehicular traffic or similar loading and shall be adequately bedded.5.3.13.2.5 Joints: All pipe joints shall be watertight and protected against external and internal loads.5.3.13.2.6 Grade: A building sewer shall be installed in a straight line to the maximum extent practicable with a uniform continuous grade not less than l/8 inch/foot, unless it can be demonstrated to the satisfaction of the Department that an alternative design can maintain adequate flow from the source and is approvable under the applicable local building code.5.3.13.2.7 Cleanouts: Building sewer cleanouts shall be installed at minimum intervals of 50 feet for three (3) inch diameter pipe and 100 feet for four (4) inch and larger diameter pipe. Cleanouts shall be provided at all changes in direction greater than 45o. Wherever possible, bends should be limited to 45o. Every house or building sewer shall have at least one (1) cleanout fitting to provide access to the plumbing. Cleanouts may be placed at greater distances provided National Standards are used to design the total collection system.5.3.14 Septic Tanks 5.3.14.1 The standard wastewater treatment system used for on site wastewater treatment and disposal shall be the dual compartment septic tank. All concrete septic tanks must be certified through the On-Site Wastewater Accreditation Program (OWAP) of the National Precast Concrete Association (NPCA) which assures long-lasting, structurally sound and watertight septic tanks. This requirement will become effective one (1) calendar year from date of promulgation of these Regulations.5.3.14.2 All septic tank treatment units shall be designed in accordance with Exhibit G and comply with standards for septic tanks as prescribed in these Regulations (see Section 5.4.3).5.3.14.3 The location of septic tanks shall be in accordance with the minimum isolation distances set forth in these Regulations as prescribed in Exhibit C. Septic tanks shall be located to avoid large elevational differences in order to facilitate periodic pumping.5.3.14.4 The minimum liquid working capacity of septic tanks shall be: 5.3.14.4.1 For flows <= 500 gpd the minimum liquid working capacity shall be 1,000 gallons.5.3.14.4.2 For flows > 500 gpd but < 2,500 gpd shall have a working capacity of 1.5 times the expected flow rate with a minimum liquid working capacity of 1,500 gallons.5.3.14.5 If large flow surges are anticipated the septic tank shall be increased in size to accommodate the surges without causing sludge or scum to be discharged from the tank.5.3.14.6 All tanks shall be watertight, non corrosive, durable and structurally sound. Materials of construction for tanks shall be one of the following: 5.3.14.6.1 Pre-cast reinforced concrete; or5.3.14.6.2 Other suitable material approved as equal by and at the sole discretion of the Department.5.3.14.6.3 Metal tanks are not a suitable material.5.3.14.7 All septic tanks shall be of multi-compartment design with a minimum of two (2) compartments. The first compartment of a two (2) compartment tank shall contain two thirds (2/3) the liquid capacity of the total volume of the tank. Tanks shall be of rectangular design.5.3.14.8 Pre-cast reinforced concrete tanks shall have a minimum wall thickness of two and one half (21/2) inches.5.3.14.9 All inlet and outlet connections shall be sanitary tees or baffles constructed of pre-cast concrete or PVC. Inlet openings may have a minimum diameter equivalent to the diameter of the house sewer but in no instance shall the diameter be less than three (3) inches. The outlet invert shall be two (2) inches below the inlet invert. The inlet and outlet baffles or sanitary tees shall extend at least 12 inches below the liquid level, but to a level no deeper than 40% of the liquid depth. Baffles or sanitary tees are not necessary for any portion of the tank if it is to be used as a pumping chamber.5.3.14.10 All pipe cutouts for inlet and outlet connections shall be sealed with a watertight concrete (95%) & bentonite (5%) grout mix or standard rubber gaskets.5.3.14.11 Connections between compartments of multi-compartment tanks shall consist of a four (4) inch diameter sanitary tee or baffle constructed of concrete. All compartment connections shall extend to a level no deeper than 40% of the liquid depth as measured from the liquid level.5.3.14.12 All inlet, outlet and inter-compartment connections shall be located to provide a minimum air space of one (1) inch between the top of the connection and the underside of the tank cover.5.3.14.13 Each tank compartment shall be equipped with an access opening and cover. The opening shall be located to provide access to each tank compartment as well as providing access to the inlet and outlet connections for routine inspections. Access openings shall be at least 20 inches square or in diameter.5.3.14.14 Each septic tank shall be constructed with a watertight access riser for each compartment and shall extend above grade at the time of installation. The riser and lid shall be made of concrete, masonry or an equivalent durable material approved by the Department. If multiple concrete risers are needed then water tight gaskets or hydraulic cement must be placed between each riser.5.3.14.15 All above finished grade access covers shall be water tight and secure from vandalism.5.3.14.16 All septic tanks shall be equipped with any outlet effluent filter approved by the Department. The maintenance of these filters is the responsibility of the property owner and must remain in service for the life of the septic tank. This unit must be maintained in accordance with the manufacturer's service instructions.5.3.14.17 All installations of septic tank treatment units shall be in accordance with Section 5.4.3.5.3.15 Grease Traps 5.3.15.1 Grease traps shall be utilized for commercial and industrial wastewater sources at the sole discretion of the Department to assure the effectiveness of on site wastewater treatment and disposal systems. Grease interceptors shall not be approved for new construction designs as replacement for the grease trap. Grease interceptors may be allowed for replacement systems when there are site limitations and low flow applications at the sole discretion of the Department.5.3.15.2 All grease traps shall be designed in accordance with the following requirements: 5.3.15.2.1 The minimum size grease trap shall be 1,000 gallons (see Exhibits E & F) and be certified through the On-Site Wastewater Accreditation Program (OWAP) of the National Precast Concrete Association (NPCA).5.3.15.2.2 The location of grease traps shall be in accordance with the minimum isolation distances set forth in these Regulations as prescribed in Exhibit C.5.3.15.2.3 The sizing of grease traps shall be based on wastewater flow data and grease retention capacity. The grease retention capacity in pounds shall be equal to at least twice the peak flow capacity in gallons per minute. The flow capacity can be determined from the individual flows from fixtures discharging into the grease trap. Exhibit E contains the minimum flow rate fixture capacities which shall be used for grease trap designs when actual calibrated metered flow data indicating peak daily flows over a three (3) year period are not available.5.3.15.2.4 All grease traps shall have multiple compartments.5.3.15.2.5 All inlet and outlet connections shall be sanitary tees or baffles constructed of pre-cast concrete or PVC. Inlet and outlet openings shall be a minimum of four (4) inches in diameter. The outlet invert shall be two (2) inches below the inlet invert. The inlet baffle or sanitary tee shall extend at least 24 inches below the liquid level. The bottom of the outlet baffle or sanitary tee shall be eight (8) inches above the tank bottom.5.3.15.2.6 Connections between compartments of multi-compartment tanks shall consist of a four (4) inch diameter sanitary tee or baffle constructed of concrete. The bottom of the sanitary tee shall be 12 inches above the tank bottom.5.3.15.2.7 The requirements of Section 5.3.14.6, 5.3.14.8, 5.3.14.9, 5.3.14.11, 5.3.14.13, 5.3.14.14, 5.3.14.15 and 5.3.14.16 shall apply to all grease traps approved in accordance with these Regulations.5.3.15.2.8 All installations of grease traps shall be in accordance with the requirements of Section 5.4.3 and testing shall be conducted in accordance with Section 5.4.3.6 of these Regulations.5.3.15.2.9 Grease traps must have access above grade.5.3.15.2.10 A copy of a contract with a licensed Class F liquid waste hauler consisting of the following conditions, as a minimum:5.3.15.2.10.1 Duration of contract.5.3.15.2.10.2 Pumping schedule.5.3.15.2.10.3 Availability of equipment.5.3.15.2.10.4 Emergency response capability.5.3.15.2.10.5 Contents will be disposed of in a manner and at a facility or location approved by the Department.5.3.15.2.10.6 Evidence that the owner or operator of the proposed disposal facility will accept the pumping for treatment and disposal.5.3.16 Lift Stations 5.3.16.1 Lift stations, as defined in Section 2.0, shall be utilized for residential and commercial wastewater systems to overcome elevational differences for conveying effluent to another system component for gravity distribution and comply with standards for septic tanks as prescribed in these Regulations (see Section 5.4.3).5.3.16.2 The location of the lift station shall be in accordance with the minimum isolation distances set forth in these Regulations as prescribed in Exhibit C and be certified through the On-Site Wastewater Accreditation Program (OWAP) of the National Precast Concrete Association (NPCA).5.3.16.3 Lift stations/packages must be approved by the Department prior to use.5.3.16.4 The requirements of Sections 5.3.14.1, 5.3.14.6, 5.3.14.8, 5.3.14.10, 5.3.14.12, 5.3.14.13, 5.3.14.14, 5.3.14.15, 5.3.17.7, 5.3.17.8, 5.3.17.10, 4.3.17.12 and 5.3.17.13 shall apply, where applicable, to all lift station tanks approved in accordance with these Regulations.5.3.16.5 All inlet pipe connections shall be located above the high water level as pre-determined by the pump installation.5.3.16.6 Check valves shall be required in all lift stations.5.3.16.7 All installations of stand-alone lift station vaults shall be in accordance with these Regulations.5.3.16.8 Demand dose (designed volume by draft/float) shall not exceed 30 gallons. If large flows are anticipated, larger demand dose float settings will be considered.5.3.16.9 Maximum gated/metered flow shall be 20 gallons per minute.5.3.16.10 Calculations required to be submitted with the application shall include static head (elevational differences) and frictional pipe losses. Manufacturer's cut-sheets for the prescribed pump and alarm, including pump curve, must also attend permit application.5.3.16.11 Lift stations designed to convey solid waste (waste generated prior to pretreatment tanks/units) must incorporate pumps capable of handling minimum two (2) inch solids.5.3.17 Dosing Chambers (see Exhibit I)5.3.17.1 Location: Dosing chambers shall be located in compliance with the minimum isolation distances of these Regulations (see Exhibit C) and comply with standards for septic tanks as prescribed in these Regulations (see Section 5.4.3).5.3.17.2 Size/Capacity: The dosing chamber shall have a minimum liquid capacity equal to the designed dose volume plus the design daily flow.5.3.17.3 The requirements of Sections 5.3.14.6, 5.3.14.8, 5.3.14.9, 5.3.14.13, 5.3.14.14 and 5.3.14.16 shall apply to all dosing chambers approved in accordance with these Regulations and must be certified through the On-Site Wastewater Accreditation Program (OWAP) of the National Precast Concrete Association (NPCA).5.3.17.4 All inlet pipe connections shall be located above the high water level as predetermined by the pump installation.5.3.17.5 All pipe cutouts shall be sealed with a watertight concrete (95%) & bentonite (5%) grout mix or standard rubber gaskets.5.3.17.6 Dosing chambers shall be constructed with a ventilation port and a watertight access manhole. The ventilation port shall be extended at least six (6) inches above finished grade while the access manhole shall also be extended above finished grade. The Department recommends six (6) inches above existing grade, at a minimum, at time of installation. The vent shall be three (3) inches in diameter and the access manhole shall be sized for easy removal of pumps. In no case shall the manhole be less than 20 inches square or in diameter. The vent shall be turned down and shall be fitted with insect and rodent proof, corrosion resistant screen. NOTE: PVC pipe caps drilled with holes is not a permissible substitute for the screen.
5.3.17.7 Pumps which are suitable for handling septic tank effluent shall be used to meet dosing requirements and shall be installed in accordance with the manufacturer's recommendations.5.3.17.8 Dosing chambers using pumps shall have an installed pump for which a replacement is readily available in the event of failure.5.3.17.9 Pumps shall be sized to discharge a flow rate equal to the combined flows from all discharge holes in the laterals when operating at designed level or head.5.3.17.10 Pumps and valves shall be equipped with suitable connections so that they may be removed for inspection or repair without entering the dosing chamber. A slide rail system or disconnect coupling accessible from outside the dosing chamber shall be utilized to allow removal and access to the pump and pump check valve for repairs and maintenance. A corrosion-proof lifting device shall be attached to the pumps and tied off at the access manhole.5.3.17.11 Check valves shall be required on all pressure distribution systems.5.3.17.12 An audible and visual high level warning device shall be installed for all pumps and shall be installed on a separate AC circuit from the pump.5.3.17.13 All pump electrical connections and alarm controls shall be NEMA 4x rated corrosion resistant and waterproof. The bottom of the control panel shall be a minimum of 24 inches above finished grade within direct line of sight of the pump or treatment device being operated.5.3.17.14 All control panels shall be UL listed.5.3.17.15 All AC circuits shall have properly sized circuit breakers installed in the control panel.5.3.17.16 Elevations for pump controls and high water level sensor elevations shall be provided in the design.5.3.17.17 Testing: All dosing chambers shall be field tested to ensure watertight conditions. Pumps, alarm controls and related appurtenances shall also be field tested to ensure accuracy and proper operation in accordance with the manufacturer's recommendations. A minimum schedule for periodic testing and calibration of the dosing chambers, pumps, alarm controls and related appurtenances shall be established and incorporated into the permit. All installed pumps shall be accompanied by instruction manuals that include operation and maintenance procedures and pump characteristics.5.3.18 Holding Tanks5.3.18.1 The use of a holding tank is an unusual circumstance wherein all wastewater is permitted to be held in a watertight structure until it is pumped and transported by vehicle to a point of disposal. The use of a holding tank on a permanent basis is prohibited except as provided in these Regulations.5.3.18.2 Permanent holding tanks are not permitted on unimproved lots.5.3.18.3 No person shall install a holding tank without first obtaining a permit from the Department.5.3.18.4 All holding tank permit applications and designs must be completed by a Class C designer. All holding tanks must be certified through the On-Site Wastewater Accreditation Program (OWAP) of the National Precast Concrete Association (NPCA).5.3.18.5 Permits may be issued, by the Department, for the permanent use of holding tanks when all of the following conditions are met:5.3.18.5.1 The site is improved with a dwelling and has been evaluated for all means of on-site wastewater treatment and disposal, including innovative/alternative, and has been deemed not suitable for an on-site wastewater treatment and disposal system.5.3.18.5.2 No community or area-wide central wastewater system is available or expected to be available within five (5) years.5.3.18.5.3 The same isolation distances as required for septic tanks can be met.5.3.18.5.4 The owner(s) contract(s) with a licensed Class F liquid waste hauler to provide hauling services to the dwelling for the period it is utilized or until connection can be made to an approved wastewater facility. Should the owners change waste haulers, a new contract shall be submitted to the Department.5.3.18.5.5 The property deed shall be amended with an Affidavit of Ownership at the time of permit issuance, which states that the dwelling is served by a permanent holding tank. The Affidavit of Ownership must be recorded at the Recorder of Deeds.5.3.18.5.6 When the governmental unit or wastewater utility provides the hauling services directly, it shall conform to the requirements for liquid waste haulers.5.3.18.5.7 Have a water meter installed to measure the in-flow of water into the building or house or a metering device measuring the flow to the tank.5.3.18.6 In an area under the control of a governmental unit, or a wastewater utility which has a recorded covenant with the owner that runs with the land, either of which is authorized to construct, operate, and maintain a large or area-wide central wastewater system, a holding tank may be installed for temporary use provided: 5.3.18.6.1 The application for permit includes a copy of a legal commitment from the governmental unit or wastewater utility that within five (5) years from the date of application the governmental unit or wastewater utility will extend to the property covered by the application, a large or area-wide central wastewater system meeting the requirements of the Department.5.3.18.6.2 The large or area-wide central wastewater system has received the necessary approvals for full operation (established sewer district or CPCN) which includes the anticipated flow to the holding tank.5.3.18.6.3 The proposed holding tank will comply with the requirements of these Regulations and tank sizing is at the discretion of the Department.5.3.18.7 Temporary use of a holding tank may be approved when:5.3.18.7.1 Installation of an approved on site system has been delayed by weather conditions; or5.3.18.7.2 The tank is to serve a temporary construction site (up to five (5) years).5.3.18.8 Applications for holding tank installation shall contain plans and specifications in sufficient detail for each holding tank proposed to be installed and shall be submitted to the Department for review and approval. The application for a permit shall be on forms provided by the Department and contain the following items: 5.3.18.8.1 A copy of a contract with a licensed Class F liquid waste hauler shall contain, as a minimum, the following conditions:5.3.18.8.1.1 Duration of contract.5.3.18.8.1.2 Pumping schedule.5.3.18.8.1.3 Availability of equipment.5.3.18.8.1.4 Emergency response capability.5.3.18.8.1.5 Contents will be disposed of in a manner and at a facility or location approved by the Department.5.3.18.8.1.6 Evidence that the owner or operator of the proposed disposal facility will accept the pumping for treatment and disposal.5.3.18.8.1.7 Method of measuring wastewater use (water meter, wastewater meter, etc.).5.3.18.8.2 A record of pumping dates and the amounts pumped shall be maintained by both the property owner and the liquid waste hauler, and be made available to the Department along with in-flow meter readings as part of the annual renewal of the permit.5.3.18.8.3 The appropriate annual inspection fee.5.3.18.9 Each holding tank shall:5.3.18.9.1 In no case have a capacity less than seven (7) days average flow from the wastewater generating facility or 2,800 gallons, whichever is larger unless authorized by the Department. When holding tanks are designed to serve the needs of a community or large system, the size shall be in conformance with standard engineering practice as determined by the Department and in accordance with an acceptable monitoring and pumping schedule.5.3.18.9.2 Comply with standards for septic tanks as prescribed in these Regulations (see Section 5.4.3).5.3.18.9.3 Be located and designed to facilitate removal of contents by pumping.5.3.18.9.4 Be equipped with both an audible and visual alarm installed on an AC circuit and placed in a location, acceptable to the Department, to indicate when the contents of the tank are at 75% of capacity.5.3.18.9.5 Have no vent at an elevation lower than the overflow level of the lowest fixture served.5.3.18.9.6 Be designed for anti-buoyancy if test hole examination or other observations indicate that seasonally high groundwater may float the tank when empty.5.3.18.9.7 Be constructed of the same materials approved for septic tanks. Holding tanks shall be watertight and structurally sound to withstand internal and external loads.5.3.18.9.8 Be equipped with a 20 inch diameter or square access opening. The access opening shall be extended to a minimum of six (6) inches above grade level at time of installation.5.3.18.9.9 All alarms shall be tested for proper operation.5.3.18.10 Each holding tank installed under these Regulations shall be inspected annually. A fee shall be charged for each annual inspection and all required documentation shall be submitted also.5.3.18.11 No liquid waste from a holding tank shall be applied directly or indirectly onto the ground surface or into surface waters.5.3.18.12 Prior to purchase of a dwelling that is currently served by a holding tank or is proposed to be served by a holding tank, the prospective buyer must sign an Affidavit of Understanding of the terms and conditions associated with use of a holding tank. This Affidavit shall be submitted to the Department to be filed with the permit and a copy of the affidavit shall be provided to the prospective buyer.5.3.19 Spare Area 5.3.19.1 Each site utilizing an on site wastewater treatment and disposal system shall have sufficient area to accommodate a complete replacement system or an acceptable alternative approved by the Department which satisfies the requirements of these Regulations. This area shall be maintained so that it is free from encroachments by accessory buildings and additions to the main building. Encroachment shall include the 10 foot isolation distance to buildings as required by these Regulations. This requirement may be waived if the application for a permit includes a copy of a legal commitment from the governmental unit that states that within five (5) years from the date of the application the governmental unit will extend to the property a community or area-wide central wastewater system meeting the requirements of the Department or an acceptable alternative is approved by the Department. The community or area-wide central wastewater system has received the necessary approvals for full operation which includes the anticipated flow to the on site wastewater treatment and disposal system.5.3.20 System Permit Applications 5.3.20.1 Permit applications must be designed in accordance with the prescribed system type and design considerations as specified in an approved site evaluation for that parcel.5.3.20.2 Applications for permits shall be made by the owner of the property or owner's legally authorized agent on forms approved by the Department.5.3.20.3 An application is complete only when the form is completed in full, signed by the owner or owner's legally authorized agent, accompanied by all required exhibits (provided an approved unexpired site evaluation report is on file) and fee. Additionally an approval letter from the appropriate governmental unit having jurisdiction that states the local governmental unit has approved the activity by zoning be submitted. Incomplete applications will not be processed and may be returned.5.3.21 The completed application shall include, at a minimum, the following site information: 5.3.21.1 Parcel and/or lot dimensions and size with a location map of project site.5.3.21.2 Slope - in absorption facility and replacement areas (percent and direction).5.3.21.3 Existing wells within 150 feet of the proposed system.5.3.21.4 Any and all watercourses or bodies of water.5.3.21.5 Distances of the existing and/or proposed on-site well(s) and absorption facilities from the nearest two reference points or established survey control.5.3.21.6 Soil boring and test pit locations along with limits of approved area as indicated in the approved site evaluation.5.3.21.7 Owner/Agent signature on plot plan drawing, straight edge must be used (no free-hand lines), to scale (acceptable scales are: 1 inch = 10, 20, 30, 40, 50, 60 and 100 feet), north arrow or compass rose and certification that designer site checked the property to confirm no changes have taken place since site evaluation was approved. Designer's signature is certification that site check was performed.5.3.21.8 Any other information required to satisfy these Regulations.5.3.22 A permit shall be issued only to the owner or easement holder of the land on which the system is to be installed.5.3.23 The Department shall either issue or deny the permit within 20 working days after receipt of the completed application. However, if conditions prevent the Department from acting to either issue or deny the permit within 20 working days, the applicant shall be notified. The Department shall either issue or return the permit within 30 working days after the mailing date of such notification.5.3.24 All permits issued for on-site wastewater treatment and disposal systems pursuant to these Regulations shall be effective for two (2) years from the date of issuance except component replacement, repair and authorization to use existing system permits which are effective for one (1) year only. If the system has been started the Department may issue a limited time period extension and an additional fee will be charged. A one year extension will, if requested, be granted by the Department upon demonstration by the applicant that no changes have occurred in system design, siting, or regulations applicable to the permit since the permit was issued and written certification to such factual findings is provided and all appropriate fees are paid.5.3.25 If any portion of the approved disposal area is disturbed during site construction activities, through grubbing, tree removal or other activities utilizing heavy equipment, a Class E system contractor must submit a certification document prepared by a Class D soil scientist on a form provided by the Department (see Exhibit FF) which states whether the area is suitable for installation or not. If not suitable, additional soil borings or test pits shall be performed within the disturbed area(s) to substantiate the initial site evaluation and a review fee will be charged.5.3.26 The Department shall deny the permit if:5.3.26.1 The application contains false information.5.3.26.2 The proposed system would not comply with these Regulations.5.3.26.3 The proposed system, if constructed, would violate a Department moratorium.5.3.26.4 A central wastewater system which can serve the proposed wastewater flow is both legally and physically available as described in Sections 3.31.9, 3.31.10 and 3.31.11 of these Regulations.5.3.26.5 Construction of an on-site wastewater treatment and disposal system is prohibited by codes, ordinances or county or municipal regulations having jurisdiction.5.3.27 Permit Denial Review The Department shall make a decision on the application which it determines will best implement the purposes of 7Del.C.Ch. 60 and these Regulations. Providing of the requisite information in the application procedure by the applicant shall not be construed as a mandatory prerequisite for the issuance of the permit by the Department.
5.3.28 Authorization to Use an Existing System Permit5.3.28.1 Application for an Authorization to Use an Existing System Permit shall be made on forms provided by the Department and shall be accepted only when the forms are complete.5.3.28.2 No person shall place into service, change the use of or increase the projected daily wastewater flow above design standards into an existing system without first obtaining an Authorization to Use an Existing System, Repair, Component Replacement or Replacement System Permit(s) as required by these Regulations.5.3.28.3 An Authorization to Use an Existing System Permit is not required: 5.3.28.3.1 Where there is a replacement of a manufactured home with similar units in manufactured home communities with on site wastewater treatment and disposal systems when an annual inspection has taken place by the Department or an authorized designee certifying that the existing system(s) is/are not malfunctioning.5.3.28.3.2 For use of a previously unused system for which a Certificate of Satisfactory Completion has been issued within one (1) year of the date that such system is placed into service, provided the projected daily wastewater flow does not exceed the design flow.5.3.28.4 For changes in the use of an existing system where no increase in wastewater flow above design standards is projected or where the design flow is not exceeded an Authorization to Use an Existing System Permit shall be issued if: 5.3.28.4.1 The existing system does not incorporate a cesspool or seepage pit.5.3.28.4.2 The existing system is not malfunctioning and is not in need of repair.5.3.28.4.3 All isolation distances from the existing system can be maintained.5.3.28.4.4 The proposed use would not create a public health hazard.5.3.28.4.5 In cases where the Department has no record of an existing on-site wastewater treatment and disposal system permit, a Class H system inspection has been performed, documentation of such inspection has been submitted to the Department, and the results either meet or exceed the regulations governing such use or an inspection of the existing system by the GDS has been performed provided the following are uncovered and found to meet or exceed the regulations governing such use:5.3.28.4.5.1 Septic tank.5.3.28.4.5.2 Distribution box or supply manifold.5.3.28.4.5.3 Beginning and end of all trenches or the four (4) corners of the bed (additional area may be required after inspection depending upon proposed use). A minimum of two (2) distribution laterals in a trench or bed absorption facility is required.5.3.28.4.6 The system had been operated in violation of these Regulations but a Repair and/or Component Replacement Permit and subsequent Certificate of Satisfactory Completion are issued.5.3.28.5 If the conditions of Section 5.3.28.4 cannot be met, an Authorization to Use an Existing System Permit shall be withheld until such time as the appropriate inspections, Repair and/or Component Replacement Permit(s) are obtained and subsequent Certificate of Satisfactory Completion are issued.5.3.28.6 If changes in the proposed use of a system would increase the daily wastewater flows above design criteria an Authorization to Use an Existing System Permit would not be issued and a Replacement System Permit would then be required.5.3.28.7 Applications for connections to existing systems that propose adding additional bedrooms will be considered on a case by case basis.5.3.28.8 The Department may allow a manufactured home to use an existing system serving another dwelling, in order to provide temporary housing for a family member suffering hardship, by issuing an Authorization to Use an Existing System Permit, if:5.3.28.8.1 The Department receives proof, in writing, from a doctor or hospital which indicates the family member is suffering physical or mental impairment, infirmity, or is otherwise disabled and is in need of temporary housing.5.3.28.8.2 The system is not malfunctioning.5.3.28.8.3 The application is for a manufactured home.5.3.28.8.4 Evidence is provided that a hardship manufactured home placement is allowed on the subject property by the governmental agency that regulates zoning, land use planning, and construction.5.3.28.9 An Authorization to Use an Existing System Permit issued for personal hardship shall remain in effect for a specified period, not to exceed cessation of the hardship. The Department shall impose conditions in the Authorization to Use an Existing System Permit that are necessary to ensure protection of public health. If the system fails and additional replacement area is no longer available, the manufactured home must be removed from the property.5.3.29 Repair and Replacement of Malfunctioning Systems5.3.29.1 Steps to repair and/or replace a component or malfunctioning system shall be initiated immediately and continued until system repair is completed. However, if, at the sole discretion of the Department, it is determined that adverse soil conditions exist due to climatic conditions that would likely preclude a successful repair, component or replacement system installation, the Department may allow a delay in commencing repairs or replacement until the soil conditions improve. If this allowance is made, a compliance date and interim system maintenance requirements shall be specified in system construction deficiencies to the system owner.5.3.29.2 No person shall repair a malfunctioning system without first obtaining a Repair or Component Replacement Permit except as permitted in Section 5.3.29.6. In no case shall a repair and/or component replacement be made to a cesspool or seepage pit or tank(s) associated with a cesspool/seepage pit unless approved by the Department. Repairs made to such systems will be considered on a case by case basis and if granted will require the issuance of a hardship permit with conditional use.5.3.29.3 Upon completion of installation of that part of a system for which a Repair, Component Replacement or System Replacement Permit has been issued, the permittee shall obtain a Certificate of Satisfactory Completion from the Department.5.3.29.4 The following criteria for a Repair, Component Repair or System Replacement Permit shall apply: 5.3.29.4.1 If the site characteristics and standards described in these Regulations can be met, then the repair and/or installation shall conform to them.5.3.29.4.2 If the site characteristics or standards described in these Regulations cannot be met, the Department may allow a repair or replacement installation in order to eliminate a public health hazard. Repairs or replacements may require the installation of an innovative/alternative system in order to eliminate a public health hazard. In such cases the Department shall use its best professional judgment in approving repairs or replacements that will reasonably enable the system to function properly.5.3.29.5 Malfunctioning systems that cannot be repaired shall be abandoned in accordance with these Regulations.5.3.29.6 Emergency Repairs5.3.29.6.1 Emergency repairs are considered emergencies only when Department offices are not open for business. Repairs and component replacements required as a result of Class H inspections do not constitute an emergency by definition and therefore are subject to normal permit application procedures.5.3.29.6.2 Emergency component replacements and repairs as specifically defined in these Regulations (see Emergency Permit definition) may be made without first obtaining a permit provided a permit is applied for the first day of normal Department operations following a weekend/holiday. Such a delayed application submittal does not relieve any person, owner or licensee, from complying with these Regulations or subsequent requirements or conditions of approval as may be imposed by the Department. Repairs and/or component replacements made under this initiative are subject to normal inspection protocols as stated in these Regulations and must be made available for inspection after work is completed.5.3.29.6.3 Emergency component replacements require drainfield verification prior to installation. The absorption facility, either trench or bed, must contain, at a minimum, two distribution laterals of equal length. If a legitimate drainfield is located a Repair or Component Replacement Permit shall be issued provided that: 5.3.29.6.3.1 The existing system is not malfunctioning.5.3.29.6.3.2 All isolation distances as required by these regulations can be maintained.5.3.29.6.3.3 The proposed use would not create a public health hazard.5.3.30 Flow Equalization Requirements 5.3.30.1 Flow equalization systems may be used for non-residential facilities that regularly and predictably operate at less than full capacity. Facilities may be permitted for flow equalization when approved by the Department.5.3.30.2 Flow Equalization Terms 5.3.30.2.1 Flow equalization cycle is the time period in which wastewater will be stored and dosed.5.3.30.2.2 Flow event is an occurrence during the flow equalization cycle in which wastewater will be generated.5.3.30.2.3 Equalized daily flow is the total volume of wastewater generated by flow events at the facility during the flow equalization cycle divided by the number of days in the cycle.5.3.30.2.4 Flow balance is a daily account of the amount of stored effluent in the equalization tank which is serviced from the incoming flow, residual storage and outgoing flow. The flow balance shows the day of the week, the amount of wastewater generated, the amount of wastewater dosed, and the residual amount of effluent left in the dosing tank each day. At the end of the flow equalization cycle, the sum of the incoming flow shall equal the sum of the amount dosed.5.3.30.3 System Sizing and Design Criteria 5.3.30.3.1 The septic tank shall be designed to accommodate the largest flow projected in a 24 hour period.5.3.30.3.2 Equalization dosing tank shall be sized to hold the:5.3.30.3.2.1 Minimum dose volume required based on the size of drainfield.5.3.30.3.2.2 Highest cumulative volume of effluent as determined by the flow balance.5.3.30.3.3 The high water alarm shall be set to activate once the equalization volume is exceeded.5.3.30.3.4 Drainfield Sizing 5.3.30.3.4.1 The equalized flow shall be calculated by adding the design daily flow for each event in the flow equalization cycle and dividing by the number of days in the cycle. Under this approval the maximum number of equalization days is seven (7).5.3.30.3.4.2 The drainfield shall be sized by dividing the equalized daily flow by the approved loading rate.5.3.31 Innovative/Alternative Wastewater Treatment and Disposal Systems5.3.31.1 Innovative/Alternative on site wastewater treatment and disposal systems may be appropriate for areas where site constraints limit the suitability for conventional system types. The Department shall consider applications for innovative/alternative wastewater treatment and disposal systems on a case by case basis. It is the policy of the Department to pursue a program of experimentation for the purpose of obtaining sufficient data for the development of innovative/alternative wastewater treatment and disposal systems, which may benefit the people of Delaware. For the purposes of this Section, applications for large and/or community systems that employ advanced treatment units which are in conformance with standard engineering practice as determined by the Department shall not be considered innovative/alternative.5.3.31.2 Sites may be considered for Innovative/Alternative System Permits where: 5.3.31.2.1 Soils, climate, groundwater, or topographical conditions are indicating the seasonal high water table or a limiting condition is encountered deeper than 10 inches below the soil surface or observation well data determines the seasonal high water table is deeper than 10 inches.5.3.31.2.2 A specific acceptable backup alternative is available in the event of system failure.5.3.31.2.3 Installation of a particular system is necessary to provide a sufficient sampling data base.5.3.31.2.4 Zoning, planning, and building requirements allow system installation.5.3.31.2.5 The system will be used on a continuous basis during the life of the project.5.3.31.3 Product approvals. Applications for innovative/alternative wastewater treatment and disposal systems shall provide documentation of the capabilities of the proposed system. Such documentation shall be in the form of proven data of long term usage of facilities similar to those specified in these Regulations, or short term documentation from controlled projects from reliable sources such as Universities or the National Sanitation Foundation International. The Department shall approve only treatment and disposal system applications that provide thorough documentation of proven technology. Alternative treatment units with flows < 2,500 gpd shall provide, at a minimum, the treatment levels prescribed for PSN3. 5.3.31.3.1 Application information required for all innovative/alternative systems or protocols must include the following information (see Exhibit EE):5.3.31.3.1.1 Name, address, phone number, fax number and email address for manufacturer, owner and agent.5.3.31.3.1.2 Executive summary describing the system, stating the type of approval sought, model numbers, and treatment levels, as applicable.5.3.31.3.1.3 System proposed is fully described with the following information: 5.3.31.3.1.3.1 Construction drawings provided detailing all system components.5.3.31.3.1.3.2 Specifications describing all materials to be used, methods of construction, means for assuring the quality and integrity of the finished product, and installation procedures.5.3.31.3.1.3.3 Materials specified for use in construction are equal or superior in physical properties and chemical durability.5.3.31.3.1.3.4 Any special conditions for use, installation, operation; and monitoring and maintenance that should be conditions of any approval document.5.3.31.3.1.4 Provide summary of pertinent literature, published research, and previous experience and performance with the system.5.3.31.3.1.5 Provide other state approvals.5.3.31.3.1.6 Provide results of any available testing, research or monitoring of pilot systems or full scale operational systems conducted by a third party independent research or testing organization. These independent studies must have adequate research from highly controlled, third party studies with rigorous research protocols or well documented long term use studies of proven wastewater technologies.5.3.31.3.1.7 Operation, maintenance and monitoring procedures for system.5.3.31.3.1.8 Notification given of any proprietary information, system, component, or device.5.3.31.3.1.9 Local distributor information and contact information.5.3.31.4 No person shall construct an innovative/alternative on site wastewater treatment and disposal system without obtaining a permit from the Department. Class E.2 or E.3 system contractors must install innovative/alternative systems.5.3.31.5 Applications for innovative/alternative systems shall be made to the Department. The application shall be complete, signed by the owner and accompanied by the required fee. The application shall include detailed system design specifications, plans and any additional information requested by the Department.5.3.31.6 Applications for innovative/alternative wastewater treatment and disposal systems shall include, but not be limited to, the following: 5.3.31.6.1 Volume and rate of wastewater flow.5.3.31.6.2 Characteristics of the wastewater.5.3.31.6.3 The degree and extent of treatment expected.5.3.31.6.4 Design criteria, specifications, and drawings including a description of the system, its capabilities, operation and maintenance requirements, unique technical features and system advantages for treatment systems plus calculations, if applicable.5.3.31.6.5 Construction materials.5.3.31.6.6 Operational and maintenance details along with their requirements.5.3.31.6.7 Class C license is required.5.3.31.6.8 Any additional information required by the Department.5.3.31.7 The permit shall: 5.3.31.7.1 Specify method and manner of system installation, mandatory operation and maintenance requirements.5.3.31.7.2 Specify method, manner and duration of system testing and monitoring, at the Department's discretion.5.3.31.7.3 Identify when and where the system is to be inspected.5.3.31.7.4 Require system construction and use within two (2) years of permit issuance.5.3.31.8 Inspection of all installed systems shall be performed by a Class C designer, Class E.2 or E.3 system contractor, the Department and the manufacturer's representative, if Class E.2 or E.3 system contractor is not certified by the manufacturer for the product. Upon completion of each phase requiring inspection by the permit, the Class E.2 or E.3 system contractor shall notify the Department, the Class C designer and manufacturer's representative, if necessary.5.3.31.9 The Department may inspect construction at any time to determine whether it complies with permit conditions and requirements.5.3.31.10 After system installation is complete and the Department has determined that it complies with permit conditions, a Certificate of Satisfactory Completion shall be issued.5.3.31.11 If the Department finds the operation of the system is unsatisfactory; the owner, upon written notification by the Department shall promptly repair or modify the system, replace it with another acceptable system, or abandon the system.5.3.31.12 The system will be monitored by the Department and/or the Department's designee in accordance with a schedule contained in the permit and the operation and maintenance requirements in 5.5.5.5.3.31.13 Should any additional guidelines be developed by the Department, the permittee would be responsible for meeting these guidelines.5.3.32 Transportation of Non-Hazardous Liquid Waste5.3.32.1 No person shall haul, convey or transport any non-hazardous liquid waste in any container without a Class F liquid waste haulers license and a Non-Hazardous Liquid Waste Transporters Permit issued by the Department in accordance with7Del.C.§ 6003(a)(2).5.3.32.2 In order to obtain a Non-Hazardous Liquid Waste Transporters Permit, the applicant must submit a completed application, demonstrate proof of bonding (see Section 5.3.32.4) and adhere to the transportation requirements (see Section 5.3.32.5).5.3.32.3 The completed application shall include, at a minimum, the following information: 5.3.32.3.1 Company and owner information.5.3.32.3.2 A list of all Class F licensees working for company.5.3.32.3.3 A description of all equipment to include collection, short-term holding, handling, and wash down equipment.5.3.32.3.4 A detailed description of the transport vehicles to include vehicle type, make and model, vehicle year, license number, state of registration, capacity size, number, and all modifications made to prevent spills and leaks.5.3.32.3.5 Type(s) of non-hazardous liquid waste being transported.5.3.32.3.6 An operations plan to include transportation route, days and hours of operation, spill reporting and cleanup plans, plans to keeping transportation vehicles clean, and recordkeeping procedures.5.3.32.3.7 Bonding certification in accordance with Section 5.3.32.4.5.3.32.3.8 A description of the non-hazardous liquid waste to include; the source of the non-hazardous liquid waste, the quantity to be transported, and any treatment the non-hazardous liquid waste has undergone before transportation.5.3.32.3.9 The destination of the non-hazardous liquid waste and a description of what is to be done with the non-hazardous liquid waste at the destination and a copy of permit/authorization letter from each disposal facility.5.3.32.3.10 A permit fee and advertisement fee are required upon submittal of a permit application, in accordance the latest DNREC fee schedule.5.3.32.3.11 All vehicles used to transport biosolids, septage or non-hazardous liquid waste shall be operated and maintained so as to be in compliance with all state and federal regulations and not present a hazard to human health or the environment through unsafe vehicle conditions. The permittee is responsible for the operation and maintenance of all vehicles operated under the permit.5.3.32.3.12 All transporters of biosolids, septage or non-hazardous liquid waste shall submit to the Department a plan for the prevention, control, and cleanup of accidental discharges. No transportation permit will be issued until such a plan has been submitted to and approved by the Department.5.3.32.3.13 All transporters shall at all times maintain commercial automobile liability insurance with a combined single limit of at least $100,000, and shall submit a Certificate of Insurance demonstrating compliance with this regulation.5.3.32.3.14 A copy of the Non-Hazardous Liquid Waste Transporters Permit must be kept in each vehicle used to transport non-hazardous liquid waste.5.3.32.3.15 At all times, and in all phases of operations, Class F licensees and/or Non-Hazardous Liquid Waste Transporters shall comply with all laws and regulations regarding the activities associated with on-site wastewater system maintenance and disposal of materials removed therefrom.5.3.32.3.16 Other information requested by the Department.5.3.32.4 Bonding requirements 5.3.32.4.1 A Non-Hazardous Waste Transporter shall execute as a requirement for obtaining and keeping a Non-Hazardous Liquid Transporters Permit under these Regulations, a person shall file with the Department a bond, Letter of Credit or other security in a form approved by the Department.5.3.32.4.2 The bond shall be payable to the Department and the obligation of the bond shall be conditioned upon the fulfillment of all requirements related to the permit.5.3.32.4.3 The amount of the bond shall be at least $5,000.5.3.32.4.4 Liability under the bond shall remain in effect until the expiration date of the permit. The Department shall release the bond after the Department determines that all of the conditions of the permit covered by the bond have been fulfilled.5.3.32.4.5 The bond shall be executed by the applicant and by a corporate surety licensed to do business in this State. Instead of having a bond executed by a corporate surety, the applicant may elect to deposit, with the Department, cash or negotiable bonds of the federal government or of this State or a Letter of Credit to the Department. The amount of the cash deposit or the market value of any securities shall be at least equal to the required sum of the bond. The Department shall receive and hold the cash or securities in trust, for the purposes for which the deposit is posted.5.3.32.4.6 The obligation of the applicant and of any corporate surety under the bond shall become due and payable, and all or any part of any cash or securities shall be applied to payment of the costs of properly fulfilling any requirement of the permit if the Department has:5.3.32.4.6.1 Notified the applicant and any corporate surety that the conditions of the permit have not been fulfilled, and specified in the notice the particular deficiencies in the fulfillment of the permit conditions;5.3.32.4.6.2 Given the applicant and any corporate surety 60 days to correct the deficiencies and to fulfill all of the conditions of the permit.5.3.32.4.6.3 Determined that, at the end of 60 days, some or all of the deficiencies specified above remain uncorrected.5.3.32.5 Transportation requirements for non-hazardous liquid wastes:5.3.32.5.1 Display the name, address and permit number of the permittee in standard block letters no less than three (3) inches high on both sides of each vehicle used for hauling purposes.5.3.32.5.2 Equip every vehicle used for hauling purposes with a watertight tank or body.5.3.32.5.3 Maintain every vehicle used for transporting in a clean and sanitary condition.5.3.32.5.4 Liquid wastes shall not be transported in an open body vehicle unless contained within suitable receptacles.5.3.32.5.5 All pumps and hose lines shall be free of leaks.5.3.32.5.6 Assure all receptacles used for transporting liquid or solid wastes are watertight, equipped with tight fitting lids and are cleaned daily.5.3.32.5.7 Obtain prior approval in writing from the Department for every site at which a hauler plans to discharge a specified amount of waste material collected.5.3.32.5.8 No waste material shall be discharged on any site without such prior approval. Written approval will be based upon the applicant having satisfied the requirements of all applicable regulations.5.3.32.5.9 Waste material collected by the hauler shall not be discharged into ditches, watercourses, lakes, ponds, tidewater or at any point where it can pollute any watercourse, water supply source, bathing area, or shellfish growing area. It shall not be deposited within 300 feet of any highway, except as provided in Section 5.3.32.5.10.5.3.32.5.10 Discharge liquid wastes into approved wastewater treatment facilities unless otherwise authorized by the Department, provided such facilities have sufficient capacity, capability to handle such liquid wastes and have authorized discharge.5.3.32.5.11 Fit all truck pumping and discharge hoses with automatic shutoff valves.5.3.32.6 Transportation of biosolids 5.3.32.6.1 For the purpose of this section, biosolids and septage are divided into three types: | Biosolid Type | Percent Solids |
| Liquid | < 15% |
| Cake | 15 - 35% |
| Dried | > 35% |
5.3.32.6.2 Liquid biosolids or septage can be pumped and transported by pipeline. If liquid biosolids are transported by truck, rail, or barge, closed watertight vessels shall be used such as tank trucks and railroad tank cars or other vessels which can provide equivalent protection against spills and leakage.5.3.32.6.3 Cake may be transported in watertight boxes, such as dump trucks properly sealed to prevent leaks, or cement type vehicles. Unless the applicant demonstrates equivalent protection against spills and leakage, when biosolid cake is transported in dump trucks, the following standards shall be met: 5.3.32.6.3.1 The trucks shall be equipped with splash guards firmly attached horizontally at the front and rear of the trailer.5.3.32.6.3.2 Each splash guard shall cover at least 25% of the trailer's open area.5.3.32.6.3.3 A minimum two (2) feet of freeboard shall be maintained between the biosolids and the top of the trailer unless the top of the trailer is completely sealed.5.3.32.6.4 The Department may require certain cake biosolids to be transported as liquid biosolids.5.3.32.6.5 Dried biosolids may be transported in open boxes, such as dump trucks, which are properly sealed to prevent leakage. The trucks shall be covered with tarps or the equivalent.5.3.32.7 Transportation of source separated materials as defined in Section 3.0 of the Regulations Governing Solid Waste, for reuse or recycling, does not require a Non-Hazardous Liquid Waste Haulers Permit, only if the material remains separated throughout the transport routes and are not recombined.5.4 Installation Requirements 5.4.1 Excavation 5.4.1.1 Clearing and Grubbing: All vegetation shall be cut and removed from the grade surface at a distance of 10 feet beyond the perimeter of the disposal area (see Lot Clearing Guidelines). Trees and shrubs shall be cut and removed at grade level while roots may be left in place. All cut materials shall be removed from the disposal area.5.4.1.2 Special care should be taken when clearing vegetation from an approved disposal area as disturbance of the soil surface may render the site unsuitable.5.4.1.3 All unsuitable excavation materials shall be discarded and the excavation shall be kept dry and de-watered from surface drainage until backfilling is completed.5.4.1.4 Excavation machinery shall be of such type and operated in such a manner that they will not compact or smear the trench or bed sidewall soils. If smearing does occur, the smeared surfaces (trench/bed sidewalls and bottoms) shall be hand-raked (scarified) to expose an unsmeared soil interface. Trenchers are required for excavation of LPP trenches. Tracked vehicles are preferred in most installation situations.5.4.1.5 Excavations below the design depth shall be brought up to proper elevation with approved fill materials installed in accordance with these Regulations and the requirements for sand-lined systems. Additional aggregate may only be used when a minimum of three (3) feet of undisturbed soil can be maintained between the bottom of the aggregate and the limiting zone. In no case shall more than one (1) foot of additional aggregate be used.5.4.1.6 The sides of the trenches or beds shall be practically plumb and scarified.5.4.1.7 The bottom of the trench or bed area shall be practically level as determined by using a transit, or laser level, with a maximum grade tolerance of two (2) inches per 100 feet.5.4.1.8 All trench or bed excavations shall be kept free of water and dry. Tamping of trench sides and bottoms is not permitted.5.4.2 Materials 5.4.2.1 Sandy fill and filter aggregate materials must come from a supplier whose in-house certification either meets or exceeds gradation requirements as listed in the first two tables below. Random inspection of supply pits and supplier's storage facilities may be performed by the Department. Tire chip (shreds) specifications are located in the third table below.5.4.2.2 Sandy fill materials shall be medium sand, sandy loam, loamy sand/sandy loam mixture. Sandy Fill Gradation Requirements
| Sieve Size | Maximum Percentage Passing Sieve |
| 3/8" | 100% |
| #4 | 95-100% |
| #50 | 5 - 30% |
| #100 | 1- 7% |
Aggregate Sizing Requirements
| Sieve Size | Maximum Percentage Retained | Minimum Percentage Passing Sieve |
| 2 1/2" | 0% | 100% |
| 2" | 0-3% | 97-100% |
| 1 1/2" | 5-10% | 90-95% |
| 1" | 50-80% | 20-50% |
| 1/2" | 25-35% | 10-25% |
| #4 | 0-5% | 0-5% |
| #8 | 0% | 0% |
Tire Chip Sizing Requirements
| Sieve Size | Percentage Passing Sieve |
| 4" | 100% minimum |
| 2" | 25% minimum |
| #4 | 5% maximum |
NOTE: The tire shreds shall have less than one (1)% (by weight) of metal fragments that are not at least partially encased in rubber. Metal fragments shall protrude no more than one (1) inch on 100% of the pieces and no more than one half (1/2) inch on 75% of the pieces (by weight). In no case shall the tire shreds contain the remains of tires that have been subjected to a fire.
NOTE: The Class E system contractor shall submit upon request a Certification of Materials for fill, aggregate and/or tire chips used in systems. This certificate shall be obtained from the supplier.
5.4.2.3 Grade boards or blocks may be used in pipe installation to assure a proper slope of less than two (2) inches per 100 feet for gravity distribution lines.5.4.2.4 Filter fabric shall be placed over the gravel with a two (2) inch overlap turned up on each side of the trench or bed.5.4.2.5 Aggregate-free chambers or any other similar devices may be used in the design, installation, and operation of on-site wastewater treatment and disposal systems in Delaware, but are subject to approval of the Department. The minimum disposal area required when using aggregate-free chambers shall be calculated by utilizing the most recent guidelines and Sections 5.3.2.2 and 5.3.2.3.5.4.3 Septic Tank Installation 5.4.3.1 Excavation: The excavation shall be large enough to allow safe, unencumbered working conditions but in no case shall the size of the excavation be less than two (2) feet beyond the perimeter of the tank. Excavations shall be kept dewatered from surface drainage until backfilling is complete.5.4.3.2 Foundations: The tank shall be placed on firm, dry, granular, undisturbed soil that has been graded level. Gravel bedding shall be used on damp or fine grained soils. A gravel bed foundation shall consist of stone which meets the specifications in Section 5.4.2 and shall be placed level to a minimum thickness of six (6) inches in the excavation. The gravel bed shall extend one (1) foot beyond the perimeter of the tank.5.4.3.3 All tanks shall be placed on a level grade and at a depth that provides adequate gravity flow from the source. Where adequate flow from the source is maintained through the use of pumping equipment, the impact of pumping rates and potential surge flows shall be evaluated so as to maintain the treatment efficiency of the septic tank unit.5.4.3.4 Previously excavated material from the tank excavation may be used for backfill provided the excavation material is dry and free of stones larger than four (4) inches in diameter, construction debris, concrete, wood and other similar materials. To equalize external pressure against the septic tank, backfill material shall be placed and compacted, extending a minimum of two (2) feet beyond the perimeter of the tank.5.4.3.5 Backfill materials shall be placed in uniform layers not more than eight (8) inches thick and compacted to no less than 85% Modified Proctor Density. Tamping shall be done in a manner that will not produce undue stress or strain on the tank. All backfill shall be free of excessive moisture.5.4.3.6 Testing: All tanks shall be tested to ensure watertight conditions and to check alignment and operation of inlet, inter-compartment and outlet connections prior to backfill. When tested, tanks shall be filled to overflowing with water to observe operation of all connections and fittings. All visible leaks in the tank observed by the installer shall be repaired prior to backfilling.5.4.4 Distribution Networks 5.4.4.1 All systems requiring a total of >= 2,500 square feet of disposal area shall have a pressurized distribution system pursuant to these Regulations.5.4.4.2 All systems requiring >= 2,500 square feet of disposal area, with the exception of low pressure pipe systems, shall be divided into a minimum of two separate alternating systems of equal size with pressurized distribution. The minimum separation between absorption facilities shall be 10 feet, with the exception of subsurface irrigation systems.5.4.4.3 All systems installed on lots where percolation rates are < six (6) mpi shall have pressure distribution systems.5.4.4.4 A minimum distance of four (4) feet and a maximum distance of six (6) feet shall separate adjacent laterals in a bed. Laterals shall be placed no farther than three (3) feet from the sidewalls of the bed. The length to width ratio for seepage beds and elevated sand mounds shall be 4:1 or greater and maximum bed width shall not exceed 25 feet, unless approved by the Department. A minimum distance of six (6) feet shall separate laterals in a trench disposal system.5.4.4.5 Gravity system distribution laterals may be connected in closed loop systems on slopes <= two (2)%.5.4.4.6 The maximum allowable trench or bed length is 100 feet for gravity distribution systems and pressure distribution systems.5.4.4.7 Each trench or bed system shall contain at least two distribution laterals. Trenches shall be utilized in all distribution systems located on slopes in excess of two (2)%, unless otherwise approved by the Department.5.4.4.8 All distribution systems shall ensure equal distribution when designed on slopes.5.4.5 Conventional Treatment and Disposal Systems5.4.5.1 Gravity Trenches and Beds (see Exhibits K, L, M and N) 5.4.5.1.1 A minimum of 12 inches of filter aggregate or gravel-less chambers shall be placed in the bed or trench. When aggregate is utilized a minimum of six (6) inches of aggregate shall be placed under the distribution laterals. The remaining filter aggregate shall be placed so that a minimum depth of no less than two (2) inches exists above the crown of the distribution pipe.5.4.5.1.2 For trenches or beds with a minimum sidewall depth of 24 inches, backfill shall be placed in accordance with permit requirements. Unless otherwise required by the Department, the construction sequence shall be as follows: 5.4.5.1.2.1 The backfill material shall be at least 12 inches in depth above the filter fabric and returned to the original grade.5.4.5.1.2.2 Backfill material shall be carefully deposited by methods which will not damage or disturb the distribution pipe or result in undue compaction of the backfill.5.4.5.1.2.3 Backfill over trenches or beds shall not be tamped.5.4.5.1.2.4 Material containing an excess of moisture shall be permitted to dry until the moisture content is within workable limits. The moisture content of the material being placed shall be within plus or minus three (3)% of optimum as determined by AASHTO Designation T 99.5.4.5.1.2.5 Backfill material which is too dry for proper placement shall be wetted. All materials shall be free of stones larger than two (2) inches in diameter, debris, trash, wood or other similar materials.5.4.5.1.3 For trenches or beds with a minimum sidewall depth of 12 inches but less than 24 inches, a capping fill shall be placed over the disposal system. The cap shall be constructed pursuant to permit requirements (see Exhibits M and N). Unless otherwise required by the Department, the construction sequence shall be as follows: 5.4.5.1.3.1 The texture of the soil used for the cap shall be of the same textural class or of one textural class finer, as the natural topsoil. All materials shall be free of stones, larger than two (2) inches in diameter, debris, trash, wood or other similar materials.5.4.5.1.3.2 Construction of capping fills shall not occur when the natural soil has a moisture content which causes loss of soil structure and porosity when worked.5.4.5.1.3.3 The disposal area shall be scarified to destroy the vegetative mat.5.4.5.1.3.4 The system shall be installed as specified in the construction permit. There shall be a minimum of 10 feet of separation between the edge of the fill and the absorption facility.5.4.5.1.3.5 Suitable backfill shall be applied to the fill site and worked in so that the two (2) contact layers (native soil and fill) are mixed. Fill material shall be evenly graded to a minimum final depth of 16 inches over the aggregate or gravel-less chambers and properly crowned.5.4.5.1.3.6 The site shall be landscaped according to permit conditions and be protected from livestock, automotive traffic or other activity that could damage the system.5.4.5.2 Elevated Sand Mounds (see Exhibit Q) 5.4.5.2.1 Sand mound absorption areas shall be plowed seven (7) to eight (8) inches deep parallel to the contour after removing the vegetative mat. Plowing shall not be done on wet soils. No plowing instruments which compact the soil shall be used. Moldboard or chisel plows are recommended.5.4.5.2.2 Immediately after plowing, sandy fill shall be placed on the up-slope edges of the plowed mound absorption area and spread to a depth as specified in the permit. Only lightweight equipment such as small track type tractors shall be allowed.5.4.5.2.3 A 12 inch bed of aggregate or gravel-less chambers shall be placed over the sandy fill. When utilizing aggregate, a minimum of six (6) inches shall be placed under the distribution lateral with the remaining aggregate placed to an additional depth of six (6) inches with at least two (2) inches over the crown of the distribution pipe.5.4.5.2.4 A minimum allowable distance of four (4) feet and a maximum distance of six (6) feet shall separate adjacent laterals in an elevated sand mound bed.5.4.5.2.5 The slope of the sandy fill not directly beneath the filter aggregate or gravel-less chambers shall be a minimum of 3:1, with 5:1 recommended by the Department.5.4.5.2.6 Mound covering or berm soil shall be loamy sand or sandy loam.5.4.5.2.7 The mound berm shall extend at least 12 inches above the 12 inch filter aggregate layer plus at least six (6) inches of topsoil cover.5.4.5.2.8 The outside slopes of the mound cover or berm shall be a minimum of 3:1 with 5:1 recommended by the Department.5.4.5.2.9 Erosion control shall be provided over the complete mound in one of the following manners: 5.4.5.2.9.1 Grass shall be planted over the entire mound and stabilized with mulch; or5.4.5.2.9.2 Sod entire mound; or5.4.5.2.9.3 Other pre-authorized methods of erosion control5.4.5.3 Low Pressure Pipe Systems (see Exhibits O & P)5.4.5.3.1 A trench width of 12 inches shall be used.5.4.5.3.2 Trenches shall be no less than five (5) feet on center.5.4.5.3.3 Nine (9) inches of filter aggregate or gravel-less chambers shall be placed in the trench. When aggregate is utilized, there shall be six (6) inches below the pipe and the remaining three (3) inches of aggregate placed around and above the pipe. There shall be a minimum of nine (9) inches of soil cover over aggregate or gravel-less chambers.5.4.5.3.4 Filter fabric shall be placed on top of the aggregate in the trench with a two (2) inch overlap turned up on each side of the trench.5.4.5.3.5 Check valves are required to eliminate the back siphoning of effluent from the laterals.5.4.5.3.6 Turn ups shall be finished below grade and protected by a four (4) inch diameter or greater Sch. 40 PVC sleeve with a cap and ferrule finished at grade.5.4.5.3.7 Timers or other electrical on/off delay devices shall be installed to ensure dosing frequencies and volumes.5.4.5.4 Wisconsin At-Grade Systems (see Exhibits U & V) 5.4.5.4.1 Wisconsin At-Grade (WAG) absorption areas shall be plowed seven (7) to eight (8) inches deep parallel to the contour after removing the vegetative mat. Plowing shall not be done on wet soils. No plowing instruments which compact the soil shall be used. Moldboard or chisel plows are recommended.5.4.5.4.2 Immediately after plowing, a 12 inch bed of filter aggregate shall be placed over the plowed area. Six (6) inches of aggregate shall be placed under the distribution lateral with the remaining aggregate placed to an additional depth of six (6) inches with at least two (2) inches over the crown of the distribution pipe. Only lightweight equipment such as small track type tractors shall be allowed when placing the aggregate.5.4.5.4.3 Filter fabric shall be placed over the aggregate bed prior to backfilling.5.4.5.4.4 WAG covering or berm soil shall be loamy sand or sandy loam.5.4.5.4.5 The WAG covering or berm shall extend at least 12 inches above the 12 inch filter aggregate layer with six (6) inches of topsoil cover.5.4.5.4.6 The outside slopes of the WAG cover or berm shall be approximately 5:1.5.4.5.4.7 Erosion control shall be provided over the complete WAG in one of the following manners: 5.4.5.4.7.1 Grass shall be planted over the entire WAG and stabilized with mulch; or5.4.5.4.7.2 Sod entire WAG; or5.4.5.4.7.3 Other pre-authorized methods of erosion control5.4.5.5 Site Restoration 5.4.5.5.1 The finished grade of the backfill over seepage bed, trench and sand-lined absorption facilities shall be crowned/sloped to provide positive drainage.5.4.5.5.2 The land adjacent to all absorption facilities shall be graded to prevent both the accumulation of surface water on the absorption facility and the flow of surface water across the absorption facility. The finished absorption facility and fill extensions shall be seeded and mulched or sodded to prevent erosion.5.4.5.5.3 Trees shall not be planted within 10 feet of the perimeter of absorption facility. All post-construction planted trees and shrubs shall be located to prevent root intrusion into the absorption facility and other components of the system. Shallow rooted shrubs are permitted (e.g., rhododendrons, azaleas).5.4.5.5.4 All areas of disturbance due to the installation of the absorption facility shall be either sodded or seeded and mulched to establish a permanent grass cover.5.4.6 Inspections 5.4.6.1 Construction 5.4.6.1.1 The Class E system contractor shall contact the Department 24 hours prior to system construction to obtain a startup number to authorize the construction.5.4.6.1.2 Changes to a permit which result in only a relocation of the system can be done by submitting a pre-inspection "as-built", which requires a minimal check against the site evaluation to ensure the system is still located within approved soils and that all required isolation distances are met. These "as-builts" are to be submitted to the Department by the Class E system contractor prior to installation. The Class E system contractor must obtain permission from the designer prior to submittal.5.4.6.1.3 When construction or repair of a system is complete, except for backfill (cover), or as required by permit, the Class E system contractor shall notify the Department or Class I system inspector, when applicable. The inspector shall inspect the installation to determine if it complies with these Regulations and the terms and conditions of the permit, unless the inspection is waived by the Department in accordance with Section 5.4.6.1.65.4.6.1.4 It is the responsibility of the Class E system contractor to confirm the results of the pre-cover inspection prior to backfilling the system.5.4.6.1.5 An inspector shall be either: 5.4.6.1.5.1 An employee of the Department.5.4.6.1.5.2 A Class C designer or his/her designee. The Class C designer must submit a list of authorized personnel, on company letterhead, to the Department for review and approval.5.4.6.1.5.3 Any person officially authorized by the Department to perform inspections of on-site wastewater treatment and disposal systems.5.4.6.1.6 The Department may waive the pre-cover inspection, provided:5.4.6.1.6.1 The installation is an on-site wastewater treatment and disposal system installed by a licensed person pursuant to these Regulations; and5.4.6.1.6.2 After system completion the Class E system contractor shall provide a construction report which certifies in writing that the system complies with the Department's Regulations within 10 calendar days of system completion. If any changes were made to the system the Class E system contractor shall also provide a detailed "as-built" plan (drawn to scale) within 10 calendar days of system completion.5.4.6.1.7 Failure to comply with Departmental Regulations and the conditions of the permit will result in verbal notification to the Class E system contractor. Failure to correct deficiencies within 10 calendar days (weather permitting) may result in written notification of such to both the Class E system contractor and permittee. Additional inspections may be required by the Department.5.4.6.1.8 Once a system has received a satisfactory pre-cover inspection or authorization to cover without a Departmental inspection, the system may be covered as specified in the approved permit. Backfilling must be completed within 10 calendar days of a satisfactory pre-cover inspection or authorization to cover by the Department, weather permitting.5.4.6.1.9 Systems requiring earthen caps and all mound systems shall require a final cover inspection pursuant to Section 5.4.6.1.3 or 5.4.6.1.6. Capping of systems must be completed within 10 calendar days of a satisfactory pre-cover inspection or authorization to cover without Departmental inspection, weather permitting.5.4.6.1.10 Inspections performed by Class C designers shall conform to guidelines established by the Department.5.4.6.1.11 In situations where the Class C designer is not comfortable approving a system, he/she is to contact the Department immediately.5.4.6.2 Inspection Protocols 5.4.6.2.1 The Class E system contractor shall be responsible for site inspection readiness which implies system completion and requires that:5.4.6.2.1.1 All septic and dosing tanks and lift stations be set and left uncovered with all appropriate risers, filters and other appurtenances installed as required by permit design. In addition, appropriate levels of water (if applicable) for lift stations and dosing tanks shall also be provided to facilitate testing.5.4.6.2.1.2 All accessory components be set and left uncovered with appropriate risers and other appurtenances installed as required by permit design.5.4.6.2.1.3 All transmission trenches from septic, lift station, or dosing tanks shall be left uncovered to verify transmission pipe diameter, level and/or bury depth. Exceptions shall be considered where high water tables are encountered. Portions of the trenches may be backfilled to facilitate site access as required.All inlet/outlet connections to all tanks and components shall be left uncovered in order to ensure pipe connection quality/integrity.5.4.6.2.1.4 The entire absorption facility (e.g. drainfield) must be left uncovered for inspection to verify trench/bed length, width and depth, sidewall condition and aggregate quality. Exceptions to this requirement may be considered for absorption facilities where site conditions such as limited site or drainfield area access, trench spacing that precludes stable equipment stabilizer placement, steep slopes, etc. are encountered. In such cases, some trenched drainfields may be backfilled to better facilitate system installation. In these instances, at the discretion of the Class E system contractor, all trenches except one may be backfilled with the exception being the most upslope trench. All pre-inspection backfilled trenches must, at a minimum, have at least two areas along the length of the trench (not including the trench beginning/end) uncovered for depth verification. In all inspection scenarios regardless of degree of pre-inspection cover, the beginning and ends of all absorption trenches must be left uncovered to verify trench length.5.4.6.2.1.5 All electrical components must be completely installed, wired and ready for testing and/or operation. This is to include, but not limited to, all timers, control panels, alarms, pumps, floats w/attending controls and other accessory appurtenances required by permit design. In cases where generators are utilized to provide electricity for testing where on-site power is not yet available all wiring should be complete with the exception of the final wiring tying into the available breaker box. All electrical connections and components utilized in an OWTDS, at a minimum, must comply with National and Delaware Electric Code (Admin. Code, Title 24, § 1400).5.4.6.3 Class H 5.4.6.3.1 For all properties utilizing an OWTDS that are sold or otherwise transferred to other ownership, the persons must have the system pumped out and inspected by a Class F and Class H licensee, respectively, prior to the completion of sale. An extension will be given to sheriff sales, short sales, cash sales and auctions for a period not to exceed 90 days from date of sale. All inspections of on-site wastewater treatment and disposal systems shall be submitted to the Department on forms approved by the Department (see Exhibit A). These forms shall be submitted within 72 hours of inspection completion.5.4.6.3.2 Must be performed by a Class H system inspector. NOTE: If an inspection has occurred within the previous 36 months and the property owner can provide documentation of such pump out and inspection, then such documentation will fulfill the requirements of 5.4.6.3.
5.4.6.3.3 For transfers of new property, the certificate of completion will fulfill the requirements of this section if issued within the previous 24 months.5.4.6.3.4 If the owner of an individual OWTDS provides proof of a licensed operator or has an annual service contract with a certified service provider then such documentation will fulfill the requirements of 5.4.6.3.5.4.6.3.5 Research historic records with DNREC (permits and/or site evaluations) through tax map numbers and previous owners. Submission of current zoning certificate required.5.4.6.3.6 All reports are required to be submitted on forms provided by the Department and are not to be altered without the prior approval of the Department (see Exhibit A).5.4.6.3.7 Interview the homeowner and/or tenants when completing the inspection forms, if available.5.4.6.3.8 Perform a visual inspection under the house for greywater lines or separate systems. NOTE: Report if area under the dwelling is not accessible.
5.4.6.3.9 Flow test from each household fixture, if applicable. NOTE: Report if access to dwelling is not available.
DISCLAIMER: The International Plumbing Code shall apply to the erection, installation, alteration, repairs, relocation, replacement, addition to, use or maintenance of plumbing systems (e.g. building drains) however this does not preclude others from visually inspecting the building drain for separate systems leaving the building.
5.4.6.3.10 Tank and Building Sewer Inspection 5.4.6.3.10.1 Locate tank.5.4.6.3.10.2 Excavate both inlet and outlet lids on septic tank, if not equipped with risers.5.4.6.3.10.3 Check flow through building sewer from house to inlet baffle, if possible.5.4.6.3.10.4 Observe and make note of effluent levels in septic tank.5.4.6.3.10.5 Observe and make note of effluent filter, if present.5.4.6.3.10.6 Measure and report sludge and scum thickness to determine the volume of solids in the tank. 5.4.6.3.10.6.1 The combined total should not exceed 30% of tank volume.5.4.6.3.10.7 Proceed with tank pump-out. This is required for all inspections and pump-out documentation may be required also. 5.4.6.3.10.7.1 Pay attention to pump-out, note abnormal items.5.4.6.3.10.8 Inspect the structural integrity of the tank.5.4.6.3.10.9 Inspect inlet and outlet pipes.5.4.6.3.10.10 Inspect all baffles.5.4.6.3.10.11 Observe flow back from drainfield, if any.5.4.6.3.11 Distribution Box Inspection, if applicable, if not go to 5.4.6.3.12. 5.4.6.3.11.1 Dig up and inspect structural integrity of distribution box.5.4.6.3.11.2 Inspect grouting and/or gaskets around both the inlet and outlets pipes.5.4.6.3.11.3 Observe water level in distribution box.5.4.6.3.11.4 Observe that all outlet inverts are set level. NOTE: In a properly functioning system, the water level should not be above the invert of the outlet pipe. If the water level is above the invert of the outlet pipes, this can be an indicator that ponding may be occurring in the drainfield. Special attention should be given to the NOTE: in 5.4.6.3.13.3 as this condition in the distribution box along with probing throughout the drainfield may eliminate the need for additional excavation.
5.4.6.3.11.5 If pump truck is still on-site, evacuate distribution box observing any backflow from drainfield.5.4.6.3.11.6 Check distribution box for cracks and inflow of sediment or carryover of FOG/Sludge. DISCLAIMER: All Occupational Safety and Health Act (OSHA) regulations must be complied with during all phases of system installation and inspection. OSHA regulations can be found at www.osha.gov or by contacting the U.S. Department of Labor.
5.4.6.3.12 Dosing Chamber Inspection, if applicable, if not go to 5.4.6.3.13. 5.4.6.3.12.1 Inspect the structural integrity of the dosing chamber, riser and lid.5.4.6.3.12.2 Inspect grouting and/or gaskets around pipe openings, tank seams and risers.5.4.6.3.12.3 Make a visual inspection of the electrical components for safe and corrosion free appearance.5.4.6.3.12.4 Check float switches for proper operation of the pump and alarm5.4.6.3.12.5 Check for timer location, if applicable.5.4.6.3.12.6 Ensure that flow is leaving the dosing chamber by taking effluent measurements before and after activating the pump.5.4.6.3.12.7 Check for weep hole, if applicable, to ensure open and below check valve. DISCLAIMER: All electrical work must meet all currently adopted State and National Electrical Codes where applicable (Admin Code, Title 24, § 1400).
5.4.6.3.13 Gravity Drainfield Inspection (Full Depth and/or Capping Fill), if applicable, if not go to 5.4.6.3.14. 5.4.6.3.13.1 Perform visual inspection of the drainfield area. NOTE: Look for wet or depressed areas with lush vegetation.
5.4.6.3.13.2 Using system records and permits, if available, locate the drain field.5.4.6.3.13.3 In all cases, the existing drainfield should be probed to find its size and extent as well as its exact location. NOTE: While probing the drainfield, care should be taken to observe the apparent operating condition of the drainfield. If, in the opinion of the inspector, there appears to be ponding in the drainfield, additional excavation, to determine the extent of the ponding and the systems functionality, may be necessary.
5.4.6.3.13.4 In the event that the dwelling/building connected to the system that is being inspected has been vacant for more than seven days, it is recommended that a flow/slug test, as described by NAWT or PSMA, be performed on the drainfield.5.4.6.3.14 Pressure Dosed Inspection (Full Depth and/or Capping Fill), if applicable, if not go to 5.4.6.3.15. 5.4.6.3.14.1 Perform the initial inspection in the same manner as 5.4.6.3.13 above "Gravity Drainfield Inspection".5.4.6.3.15 Elevated Sand Mound Inspection, if applicable, if not go to 5.4.6.3.16. 5.4.6.3.15.1 Perform the initial inspection in the same manner as 5.4.6.3.13 above "Gravity Drainfield Inspection".5.4.6.3.15.2 Ensure the satisfactory condition of grass cover for stabilization5.4.6.3.16 Low Pressure Pipe System Inspection (Full Depth and/or Capping Fill), if applicable, if not go to 5.4.6.3.17. 5.4.6.3.16.1 Perform the initial inspection in the same manner as 5.4.6.3.13 above "Gravity Drainfield Inspection".5.4.6.3.16.2 Perform a visual inspection of the drainfield. NOTE: Look for wet, depressed areas with lush vegetation.
5.4.6.3.17 Wisconsin At-Grade System Inspection, if applicable, if not go to 5.4.6.3.18. 5.4.6.3.17.1 Perform the initial inspection in the same manner as 5.4.6.3.13 above "Gravity Drainfield Inspection".5.4.6.3.17.2 Perform a visual inspection of the drainfield. NOTE: Look for wet, depressed areas with lush vegetation.
5.4.6.3.18 All Innovative/Alternative systems including advanced treatment unit's (ATU's) and alternative drainfield systems may only be inspected by a Class H licensee that has been certified through DNREC approved training for that ATU or alternative drainfield system. Proof of certification must be submitted to DNREC. A Class H license alone is not adequate enough for this task.5.4.6.3.19 Scale drawing must contain, at a minimum: 5.4.6.3.19.1 A site drawing to scale, straight edge must be used (no free-hand lines), must show a reference point such as numbered utility pole, telephone or electrical box, building(s), property corners or fixed survey markers, or GPS coordinates. A minimum of two (2) such reference points should be noted on the site sketch. Site sketches shall be based on a whole number scale not to exceed one (1) inch equals 100 feet. Acceptable scales are: 1 inch = 10, 20, 30, 40, 50, 60, or 100 feet.5.4.6.3.19.2 A north directional arrow.5.4.6.3.19.3 Indicate location of central water line or on-site well. All on-site wells must be measured from two (2) reference points or established survey control.5.4.6.3.19.4 Identify each wastewater treatment and disposal system component.5.4.6.3.19.5 Mark distances from fixed reference points (e.g. property corners, existing dwelling) or established survey control points for each wastewater treatment and disposal system component.5.4.6.3.19.6 Should an existing approved permit drawing be available the drawing maybe used, but the inspector must either note on the drawing that "no changes were found" or clearly mark all the changes on the permit drawing.5.4.6.3.20 All cesspools and seepage pits are prohibited and when found must be replaced within one (1) year in accordance with these Regulations.5.4.6.3.21 All metal tanks and metal distribution boxes are prohibited and when found must be replaced in accordance with these Regulations.5.4.6.3.22 Once received, the Class H Inspection Report shall be reviewed for compliance with current Regulations. If not in compliance, the Class H inspector will be notified. The Class H inspector must submit the required corrections within 72 hours of notification to the Department and the owner.5.4.6.3.23 If repairs are made to the system, after receiving an unsatisfactory rating during a Class H inspection, another Class H inspection must be performed or paperwork submitted to the Department outlining all work completed to return system to a satisfactory condition.5.4.7 Certificate of Satisfactory Completion 5.4.7.1 The Department shall issue a Certificate of Satisfactory Completion, if, upon inspection of the installation, the system complies with the Department's Regulations, the conditions of the permit, and a Construction Report is submitted to the Department.5.4.7.2 A system shall be backfilled (covered) when:5.4.7.2.1 The Class E system contractor is notified by the Department that inspection has been waived; or5.4.7.2.2 The inspection has been done and authorization has been granted to cover the system.5.4.7.3 Corrections necessary to meet requirements for satisfactory completion shall be made within 10 calendar days after written notification by the Department, unless otherwise required and weather permitting.5.4.7.4 A Certificate of Satisfactory Completion shall be valid for a period of two (2) years from the date of issuance. After the two (2) year period, the Regulations for Authorization to Use an Existing System Permit shall apply (see Section 5.3.28).5.4.7.5 Denial of a Certificate of Satisfactory Completion may be appealed in accordance with7Del.C.§ 6008.5.4.7.6 If the system has been placed into operation without the required Certificate of Satisfactory Completion, a Notice of Non-Compliance shall be issued to the owner and must be corrected within 10 calendar days or system must be abandoned in accordance with Section 5.4.8.3.5.4.8 Abandonment of On-Site Wastewater Treatment and Disposal Systems 5.4.8.1 General Requirements 5.4.8.1.1 All systems shall be abandoned by a Class E system contractor or other governmental appointee.5.3.8.1.2 Within 10 calendar days of abandonment, the Class E system contractor or governmental appointee shall submit a System Abandonment Report on a form provided by the Department (see Exhibit AA). The report shall be filled out completely and signed by the system contractor or governmental appointee.5.4.8.2 The system shall be properly abandoned when:5.4.8.2.1 A central wastewater system becomes available and the building sewer has been connected thereto; or5.4.8.2.2 The source of wastewater has been permanently eliminated.5.4.8.3 Procedures for Abandonment: 5.4.8.3.1 The septic tank, cesspool or other treatment unit shall be pumped by a Class F liquid waste hauler to remove all of the contents.5.4.8.3.2 The septic tank, cesspool or other treatment unit shall be removed or filled with sand, bank run gravel, or other material approved by the Department. NOTE: If metal tank is encountered, it must be removed and properly disposed of.
5.4.8.3.3 The system's building sewer shall be permanently capped.5.4.8.3.4 The System Abandonment Report shall be submitted to the Department within 10 calendar days.5.4.8.3.5 In addition, the requirements of Section 5.4.5.5 must be adhered to to properly restore the site after system abandonment.5.5 Operation and Maintenance 5.5.1 The owner shall be responsible for operating and maintaining their on site wastewater treatment and disposal systems.5.5.2 Each on site wastewater treatment and disposal system shall be pumped by a licensed Class F liquid waste hauler once every three (3) years and innovative/alternative treatment systems shall be pumped according to manufacturer recommendations unless determined that the tank is less than one-third (1/3) full of solids. The schedule shall be prescribed in accordance with current Department guidelines based on the size of the treatment unit and anticipated number of residents. The owner of the on site wastewater treatment and disposal system shall maintain a record indicating the system has been pumped and provide such documentation to the Department upon request. 5.5.2.1 Effluent filters shall be cleaned as per manufacturer's recommendations, at a minimum, or as necessary to prevent backing up into the dwelling. Cleaning is accomplished by hosing off the filter over the open inlet cover riser.5.5.3 Grease traps shall be cleaned when 75% of the grease retention capacity has been reached.5.5.4 The sites of the initial and replacement absorption facilities shall not be covered by asphalt or concrete or subject to vehicular traffic or other activity which would adversely affect the soils. These sites shall be maintained so that they are free from encroachments by accessory buildings and additions to the main building. 5.5.4.1 There shall be no lawn irrigating systems installed over the absorption facility when the absorption facility is active.5.5.5 The Department may impose specific operation and maintenance requirements for on site wastewater treatment and disposal systems to assure continuity of performance. All innovative/alternative systems have operation and maintenance requirements. These requirements follow; 5.5.5.1 For new construction, prior to the Department granting a Certificate of Completion, the permittee, unless certified by the homeowner training program, must enter into a service contract with a certified service provider initially, for a minimum of two (2) years starting at the onset of initial system operation. For replacement systems, this service contract must be submitted with the permit application. Specifically, the service contract shall prescribe an Inspection Program and Homeowner Training Program as outlined below: 5.5.5.1.1 Inspection Program. The inspection program shall include the following: a schedule indicating inspection frequency, inspection objective(s), inspection details, necessary operation and maintenance activities, additional sampling if required, and record keeping requirements. 5.5.5.1.1.1 Inspection Frequency/Objective: The service contract must outline that the certified service provider is to inspect the system once every six (6) months or otherwise as approved by the Department.5.5.5.1.1.2 Inspection Reports: The contract must outline that the certified service provider must document all inspections. Operation inspection reports shall indicate the following: date and time of the inspection, sampling and laboratory analysis results, operation and maintenance performed, repairs, an assessment indicating the current performance status of the entire treatment and disposal system, and any corrective actions that must be taken prior to the next inspection. All inspection reports shall be on forms approved by the Department.5.5.5.1.2 Homeowner Training Program. The service contract must state that the certified service provider is required to meet with the homeowner during the first sixth month inspection. The certified service provider is to educate the homeowner on the components of the system and on the proper operation and maintenance requirements. At this time, the certified service provider shall provide the homeowner with an operation and maintenance manual.5.5.5.2 Following the initial two (2) year period, the permittee is required to maintain a service contract for the system by: renewing the existing contract annually, at a minimum, contracting with another certified service provider or being certified by the homeowner training program. The service contract must contain the inspection program requirements from Section 5.5.5.1.1.5.5.5.3 All reports and contract renewals from the previous year shall be submitted by February 1st of each year to the Department. The certified service provider must submit all inspection reports to the Department and permittee. The permittee shall submit any contract renewals as necessary to the Department.5.5.5.4 The Department reserves the right to collect and analyze samples to ensure proper treatment levels and system performance.5.5.5.5 The Department may increase inspection frequencies as warranted. A notice outlining new frequencies and cause will be provided to the permittee prior to initiation.5.5.5.6 Transferability. Within 90 days after the transfer of the real property which utilizes an innovative/alternative system, the owner shall notify the Department. Transfer of the maintenance agreement must also be completed within this 90 day period.5.5.6 Innovative/Alternative systems without permit conditions requiring a certified service provider shall be inspected by the Department or its designee once every three (3) years and a fee may be required.5.6 Waivers. Waivers from any provisions contained in these Regulations may be granted after a public notice and hearing, if warranted. 5.6.1 Applications for Waivers. A separate application shall be made to the Department for each site considered for a waiver.5.6.2 Formal 5.6.2.1 A letter signed and submitted by the property owner or their authorized agent requesting a Formal Waiver (FW). This submittal must include all appropriate fees.5.6.2.2 A site evaluation report conducted by a Class D soil scientist.5.6.2.3 At the sole discretion of the Department, a design prepared by a licensed Class C designer may be required to show exact location of a proposed system with initial submission of the FW application.5.6.2.4 A list of all property owners' names and addresses located contiguous to the waiver site.5.6.2.5 The location of all current wells within 150 feet of the property.5.6.2.6 The Department shall advertise a FW in accordance with7Del.C.§ 6004 to include direct notification of adjacent property owners. The Department will not hold a public hearing unless a meritorious request is made.5.6.2.7 Upon approval of the FW the following will be required:5.6.2.7.1 A completed permit application prepared by a licensed Class C designer, if not previously submitted.5.6.2.7.2 Only those items stated in writing in the initial request will be granted in the FW.5.6.3 Rural Area 5.6.3.1 Waivers for any provision of these Regulations may be granted by the Secretary provided that: 5.6.3.1.1 The owner executes and records in the appropriate County Office of the Recorder of Deeds an affidavit, on a form approved by the Department, which notifies prospective purchasers that the property is subject to a Rural Area Waiver (RAW).5.6.3.1.2 The parcel size is not less than 10 acres.5.6.3.1.3 The permit is for an on site wastewater treatment and disposal system designed to serve a single family dwelling.5.6.3.1.4 The on site wastewater treatment and disposal system will function in a satisfactory manner so as not to create a public health hazard.5.6.3.1.5 Each RAW application shall include: 5.6.3.1.5.1 A letter signed and submitted by the property owner or their authorized agent requesting a RAW. This submittal must include all appropriate fees.5.6.3.1.5.2 A site evaluation report conducted by a Class D.2 or D.3 soil scientist to include the requirements of Section 5.6.3.1.5.6.3.1.5.3 At the sole discretion of the Department, a design prepared by a licensed Class C designer may be required to show exact location of a proposed system with initial submission of the RAW application.5.6.3.1.5.4 Proof the parcel is a minimum of 10 acres (survey or statement from zoning office).5.6.3.1.5.5 Location of any wetlands, refer to Statewide Wetlands Mapping Project (SWMP) map, and State Tidal Wetlands maps, if applicable.5.6.3.1.5.6 A proposed disposal location which is a minimum of 100 feet from all property boundaries (when soil conditions allow).5.6.3.1.5.7 The location of all wells within 150 feet of the property boundaries.5.6.3.1.5.8 A list of all property owners' names and addresses located contiguous to the site.5.6.3.1.5.9 The Department shall advertise the RAW application in accordance with7Del.C.§ 6004 to include direct notification of adjacent property owners.The Department will not hold a public hearing unless a meritorious request is made.5.6.3.1.5.10 Prior to submitting the site evaluation, the Class D soil scientist in conjunction with the Department will determine the system type, design specifications and return this information to the owner, or designated agent.5.6.3.1.6 Upon approval of the RAW, the following criteria will be required: 5.6.3.1.6.1 A completed permit application prepared by a licensed Class C designer, if not previously submitted.5.6.3.1.6.2 An affidavit of a RAW (as part of the permit application).5.6.3.1.6.3 Only those items stated in writing in the initial request will be granted in the RAW.5.6.4 Hardship 5.6.4.1 The Secretary may grant waivers from any provision of these Regulations in cases of extreme and unusual hardship.5.6.4.2 The Department may consider the following factors in reviewing an application for a waiver based on hardship including, but not limited to: 5.6.4.2.1 Advanced age or bad health of the applicant.5.6.4.2.2 Need of applicant to care for aged, incapacitated, or disabled relatives.5.6.4.2.3 Relative insignificance of the environmental impact of granting a waiver.5.6.4.3 Hardship waivers granted by the Secretary may contain conditions such as: 5.6.4.3.1 Permits for the life of the applicant.5.6.4.3.2 Limiting the number of permanent residents using the system.5.6.4.3.3 Use of conventional on-site wastewater treatment and disposal systems for specified periods of time.5.6.4.3.4 Any other conditions which the Secretary finds in his/her sole discretion to be appropriate.5.6.4.4 At the time of the application, the applicant must designate on the application that it is for a hardship waiver.5.6.4.5 Documentation of hardship must be provided before the application is referred to the Department for action.5.6.4.6 Department personnel shall strive to aid and accommodate the needs of applicants for waivers due to hardship.5.6.5 Waiver Hearings 5.6.5.1 The hearing officer shall hold a public hearing in conformance with7Del.C.§ 6006.5.6.5.2 The hearing shall be held in the county where the property is located.5.6.5.3 No waiver may be granted unless the hearing officer, or in the case of an appeal to the Environmental Appeals Board, finds:5.6.5.3.1 Strict compliance with the provision of these Regulations is inappropriate for cause; or5.6.5.3.2 Special physical conditions render strict compliance unreasonable, burdensome, or impractical.7 Del. Admin. Code § 7101-5.0
17 DE Reg. 752 (1/1/2014) (Final)