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HomeMy Public PortalAboutSewage Ordinance - Affidavit of Publication - 1980CITY OF MEDINA INDIVIDUAL SEWAGE TREATMENT AND DISPOSAL SYSTEMS CODE Regulating the installation, construc- tion, alteration, extension and repair of in- iividual soil treatment and sewage dis- iosal systems: requiring permits for. and licensing of persons engaged in the con- struction thereof: and providing for in- spection and prescribing penalties. SECTION I TITLE This code and its provisions shall be known as the Individual Sewage Treat- ment and Disposal Systems Code of the City of Medina. SECTION II PURPOSE The purpose of this ordinance is to promote the health, safety, morals. prosperity, esthetics and general welfare of the residents and property owners of the City of Medina: to protect land, water and other natural resources within and outside the city from impairment, pollu- tion, or destruction as charged under Min- nesota Statutes 1973, 116B.01: to prevent flooding and flood damage; to facilitate the division and subdivision of land; to save residents and property owners from the large and unnecessary expenses of providing central sewers and water ser- vices where such expenses may reasonably be avoided. The City of Medina determines that, in areas not served by public sanitary sewer, the effluent from sewage tanks (septic and aerobic) shall be disposed of by a soil -ea tment and disposal system which shall ie a series of drainfield trenches herein referred to as "subsurface soil treatment and disposal systems". SECTION III DEFINITIONS For the purposes of these regulations, certain terms or words used herein shall be interpreted as follows: the word "shall" is mandatory, the words "should" and "may" are permissive. All distances. unless otherwise specified, shall be measured horizontally. Administrator - That person charged with the enforcement of local sanitary or- dinances, including, but not limited to zon- ing administrators, sanitarians, building officials, and health officers. Aerobic Tank - Any sewage tank which utilizes the principle of oxidation in the decomposition of sewage by the introduc- tion -of air into the sewage. Agency - The Minnesota Pollution Con- trol Agency Agency Approved Disposal Facility - Any disposal facility which has an NPDES (National Pollutant Discharge Elimina- tion System) Permit or State Disposal System Permit or letter of approval from the Agency. AIternative System (Innovative 'ystem) - An individual sewage treatment 'stem designed to mitigate site charac- eristics of high groundwater and slow permeability. The two general types of systems are the innovative subsurface ab- sorption systems (including shallow . trenches and equal distribution system) and innovative mound systems. Engineer- ing methods and devices employed by in- novative systems are presented in the Design :Manual. Raffle - A device installed in a septic tank for proper operation of the tank, and to provide maximum retention of solids. Includes vented tees and submerged pipes in addition to those devices that are nor- mally called baffles. Bedrock - That laver of parent material which is consolidated and unweathered. Bedroom - Any room within a dwelling unit which is designed, used, or intended for use as a sleeping room. Building Drain - That part of the lowest piping of the drainage system which receives the discharge from soil, waste, and other drainage pipes inside the walls of the building and conveys it to the building sewer beginning at least one foot outside the building footings. Building Sewer - That part of the drainage system which extends from the end of the building drain and conveys its discharge to an individual sewage treat- ment system. Adequate cleanouts shall be provided as per State Plumbing Cedes. Capacity - The liquid volume of a sewage tank using inside dimensions below, the outlet. Cesspool- An underground pit into which raw household sewage or other un- treated liquid waste is discharged and from which the liquid seeps into the sur- rounding soil. Clerk - The Clerk of the City of Medina. Council - The Council of the City of Medina. Distribution Pipes - Perforated pipes or agricultural drain tiles that are used to distribute• sc.aWagR tank effluent in a ^,il treatment system. Dosing - Dosing is the periodic applica- tion of effluent to soil absorption area. Distribution Device - A device which is used to distribute sewage tank effluent to the distribution pipes. Dosing Device - A pump, siphon, or other device that is used to discharge sewage tank effluent from the dosing chamber into the distribution device or treatment system. Dosing Chamber - (or pump pit or wet well) A tank or separate compartment following the sewage tank which serves as a reservoir for the dosing device. Dwelling Unit - A residential building or portion thereof intended for occupancy by a single family but not including hotels, motels, boarding or rooming houses or tourist homes. Equal Distribution - The distribution of sewage effluent equally over the entire soil absorption area. Existing System - Any individual sewage tratment system installed before the effective date of this regulation, and any system for which a permit has been issued by the local unit of government before the effective date of these stan- dards. Filter Material - Clean rock, crushed igneous rock or similar insoluble, durable and decay -resistant material free from dust, sand, silt, or clay. The size shall range from one-half inch minimum diameter to two and one-half inch effec- tive diameter. Floodplain - Means lands which are sub- ject to flooding during a ten-year flood as defined herein. Note: If there arp any lake levels which have been recorded for a number of years by the Department of Natural Resources. these should be referred to and the highest kr., wn level of the watertable in the lake should be the reference point for the loca- tion of sewage disposal systems. If a flood - plain ordinance is in effect, the required regulations in the Minnesota Shoreland Ordinance apply. Greywater - Liquid waste from a dwell- ing produced by bathing. laundry. culinary operations and from flood drains. and specifically excluding toilet waste. Impermeable - With regards to bedrock. a bedrock having no cracks or crevices and having a vertical permeability less than one inch in 24 hours shall be con- sidered impermeable. With regard to soils, a soil horizon or layer having a ver- tical permeability less than one inch in 24 hours shall be considered impermeable. Individual Sewage Treatment System - A sewage treatment system, or part thereof, serving a dwelling, or other small living or business unit, or group thereof, which utilizes soil treatment and disposal. Lawn Area - The area bounded by the dimensions required for the proper loca- tion of the soil treatment area. Mottling - A zone of chemical oxidation and reduction activity, appearing as splotchy patches of red, brown, orange, and gray. Mound System - A system where the soil treatment area is built above -ground to overcome limits imposed by proximity to watertable or bedrock, or by rapidly or slowly permeable soils, as described in the Medina Sewer System Design Manual. New System - Any individual sewage treatment system installed after the ef- fective date of these standards. Official Soil Map - The Soil Survey of Hennepin County, Minnesota, 1974, a copy of which is attached hereto and made a part hereof by reference, adopted as the official Soil Survey of the City of Medina together with any detailed supplemental operational Soil Surveys made pursuant to such map. Percolation Rate - The time rate of drop of a water surface in a test hole as specified in Section IV of this regulation. Non-comforming System - A prohibited system: a system located within a designated 10-year floodplain; a system which does not meet all the location design or construction standards of the Design Manual: a system which is being used beyond its capacity; a system which has failed to treat properly and/or dispose of the entire current input; a system results in one or more of the following con- ditions: in A discharge of pollutants, or any li- quid, to the surface of the ground or to any lake, stream, or other body of water. (21 An inability to accept a sewage input from an unoccupied building. (3) The creation of a safety hazard due to unprotected or improper construction or maintenance. (4) The creation of any type of public nuisance. Plastic Limit - A soil moisture content below which the soil may be manipulated for purposes of installing a soil treatment system. and above which manipulation will cause compaction and puddling. Pressure Distribution System - This dis- tribution system consists of a pumping chamber and properly sized pumps and pipe to accomplish equal distribution. Privy - A toilet waste treatment device consisting of a pit where only toilet wastes, fecal matter. urine and toilet paper are discharged. The privy shall be used in conjunction with a greywater system. Sand - A soil texture composed by weight of at least 25 percent of very coarse. coarse. and medium sand varying in size from two to 0.25 mm. less than 50 percent of fine or very fine sand ranging in size between 0.25 and 0.50 mm, and no more than ten percent of particles smaller than 0.05 mm. Seepage Pit - (or leaching pit or dry well) An underground pit into which a sewage tank discharges sewage or other liquid waste and from which the liquid seeps into the surrounding soil through the bottom and openings in the side of the pit. Septage - Those solids and liquids removed during periodic maintenance of a septic or aerobic tank, or those solids and liquids which are removed from a holding tank. Setback - A separation distance measured horizontally in which no In- dividual Sewage Treatment and Disposal System can be constructed. Sewage - Any water carried domestic waste, exclusive of footing and roof drainage, from any industrial, agricultural, or commercial establish- ment, or any dwelling, or any other struc- ture. Domestic waste includes, but is not limited to liquid waste produced by bathing, laundry, culinary operations and liquid wastes from toilets and floor drains, and specifically excludes animal waste and commercial process water. Sewage Tank - A water -tight tank used in the treatment of sewage. Includes, but is not limited to, septic tanks and aerobic tanks. Sewage Tank Effluent - That liquid which flows from a septic or aerobic tank under normal operation. Septic Tank - Any watertight, covered receptacle designed and constructed to receive the discharge of sewage from a building sewer, separate solids from li- quid, digest organic matter. store solids through a period of detention, and allow the clarified liquids to discharge to a soil treatment system. Site - The proposed on -site sewage treat- ment system area. Site Evaluator - Any person so designated by the city such as a soil scien- tist. geologist. or registered professional engineer. Slope - The ratio of vertical rise or fall to horizontal distance, Soil Boring - Any type of excavation capable of revealing detailed charac- teristics of penetrated soils Soil Classification- Where soil particle sizes or textures are specified in this regulation, they refer to the Guide for USDA Soil Textural Classification (See Figure 11). Soil Permeability - The rate of water in- filtration into the soil expressed as a rate (inches per hour). Permeability is most often measured by the Uhland Core method where the rate at which water passed through a water saturated soil un- der one-half foot of standing water. Soil Scientist - A person who has had four years academic training and who has had field experience in the identification of the soil types defined in the Soil Survey of Hennepin County. Minnesota. 1974. Soil Survey - The systematized study of soils, including the study of particulate makeup. slope. permeability. and other morphological soil characteristics: the systematized study of soil behavior and predictions of soil behavior for purposes of individual soil treatment and Sewage Dis- posal Systems: the classification of soils into defined soil types: soils mapping to show the boundaries of specific soil types and their geographic distribution, as set forth in Standard Soil Survey USDA. a copy of which is attached hereto and made a part hereof by reference. Soil Treatment Area - An area where sewage tank effluent is treated and dis- posed of below the ground surface by filtration and percolation through the soil. and also by transpiration. Includes those systems commonly known as seepage bed. trench drainfield, disposal field, and in- cludes mounds. electroosmosis systems, and seepage pits. Standard System - An individual sewage treatment system employing a sewage tank and the soil treatment system com- monly known as trenches. drainfield, or leachfield. Surfacewater Flooding - On major streams, the ten-year floodplain as defined by the Department of Natural Resources, or where a floodplain is es- timated by local officials and/or the Department of Natural Resources. On lakes, high water levels as determined or recorded by the Department of Natural Resources or, in the case of no depart- ment record, by local records or ex- perience. Other surfacewater flooding or high water areas should be determined by local information. Ten -Year Flood - A flood which has the probability of occurrence once in ten years, or the level to which floodwaters have a ten percent chance of rising in any given year. Toilet Waste Fecal matter urine. toilet paper and any water used for flushing. Valve Box - Any device which can stop sewage tank effluent from flowing to a portion of the soil treatment system: in- cluding but not limited to caps or plugs on distribution or drop box outlets• divider boards. butterfly valves. gate valves or other mechanisms. Watertable - The highest elevation in the soil where all voids are filled with water. as evidenced by presence of water or soil mottling or other information. Normal (or Ordinary) High Water Mark - A mark delineating the highest water level which has been maintained for a suf- ficient period of time to leave evidence upon the landscape. The normal high water mark is commonly that point where the natural vegetation changes from predominantly aquatic to predominantly terrestrial. Watertight - Constructed so that no water can get in or out below the level of the outlet. Water Usage - Water usage shall be es- timated by the best current available data. SECTION IV GENERAL PROVISIONS A. Applicability 1. General These standards define the minimum standards for individual sewage treatment systems installed in Medina. It is inten- ded that the administration and enforce- ment of these standards be conducted by the Administrator of the City of Medina except for the following systems which re- quire State Disposal System Permits: a. Systems disposing of waste other than sewage. b. Collector systems which serve fifteen (15) dwellings, or 5,000 gallons per day, whichever is less. c. Individual sewage treatment systems which serve a single facility generating greater than 15,000 gallons per day. In all three cases, approval by the Ad- ministrator shall be obtained prior to the issuance of a license or permit by either the State Department of Health or the Minnesota Pollution Control Agency. 2. New and Existing Systems a. All systems installed subsequent to the adoption of these standards shall be located, designed and constructed in ac- cordance with the requirements of these standards. b. All existing systems which are not located, constructed or installed in accor- dance with the provisions of these stan- dards, shall be brought into compliance as closely as is practicable with the require- ments of these standards whenever such system fails, causes a nuisance, or re- quires a repair or alteration (not including maintenance) . B. Discharge Prohibited Raw sewage, septic tank effluent. or seepage from a soil treatment system shall not be discharged to the ground sur- face. abandoned wells, or bodies of sur- facewater, or into any rock formation the structure of which is not conducive to purification of water by filtration, or into any well or other excavation in the ground. C. Lot Size A lot shall have an adequate area for all expected improvements in addition to an adequate area of soil suitable for the in- stallation of the individual sewage treat- ment system in accordance with all re- quirements pertaining thereto. D. Connection to Public Sewer Nothing shall prohibit the use of in- dividual sewage treatment systems where public or other sewage or other waste dis- posal systems are not available or cannot reasonably be, made available. provided site and soil conditions are satisfactory as outlined in Section 12. E. Treatment Required The system or systems shall be designed to receive all sewage from the dwelling. building. or other establishment served. Footing or roof drainage shall not enter any part of the system. F System Components The system shall consist of a building sewer, sewage tank, and soil treatment system. A11 sewage shall be treated in a sewage tank or toilet waste treatment device. and the sewage tank effluent shall be discharged to the soil treatment system. G. Prohibited Installations Cesspools and seepage pits shall not be installed. H. System Sizing Where the construction of additional bedrooms, the installation of mechanical equipment or other factors likely to affect the operation of the system can be reasonably anticipated, the installation of a system for such anticipated need shall be required. SECTION V LICENSING No person, firm or corporation shall engage in the business of installing, con- structing, or repairing sewage disposal systems within the municipality without first obtaining a license to carry on such occupation •from the Council and procur- ing and posting with the Clerk a bond in the amount of Two Thousand ($2,000) dollars in favor of the municipality and the public, conditioned upon the faithful per- formance of contracts and compliance with this ordinance. Such license shall be renewable annually on or before April 30 and may be revoked or refused renewal by the Council for cause. Any installation, construction, alteration or repair of a sewage disposal system by a license in violation of the provisions of this or- dinance or refusal on the part of a licensee to correct such defective work performed by such licensee shall be cause for revoca- tion of or refusal to renew a license. Before any license issued under the provisions of this section may be revoked or its renewal refused. the licensee shall be given a hearing to show cause why such license should not be revoked or refused. Notice of the time, place, and purpose of such hearing -shall be in writing. The an- nual license fee shall be fifty ($50) dollars. Application for such license shall be made annually on a form furnished by the Coun- cil. The persons licensed shall demonstrate their knowledge and ability to install in- dividual soil treatment and sewage dis- posal systems by attending and com- pleting at least one Home Sewage Workshop conducted by the University of Minnesota Extension Service. SECTION VI PERMITS A. Applicability No person. firm. or corporation shall in- stall, alter. repair or extend any individual sewage disposal system in the municipality without first obtaining a per- mit therefor from the Building Inspector. For specific installation, alteration. repair. or extension; and at the time of ap- plying for said permit. a fee shall be paid based on the city fee schedule. Such per- mits shall be valid for a period of six months from date of issue. Work done without permit shall be subject to double fee. B. Application Forms Applications for permits shall be made in writing upon printed blanks or forms furnished by the Council and shall be signed by the applicant. C. Descriptions and Plans Each application for a permit shall have thereon the correct legal description of the property on which the proposed in- stallation, alteration, repair, or extension is to take place and each application for a permit shall be accompanied by a plot plan of the land showing the location of any proposed or existing buildings and trees located on the property within 75 feet of the existing or proposed system and complete plans of the proposed system with substantiating data, if necessary, attesting to the compliance with the minimum standards of this or- dinance. A complete plan shall include the size and design of all parts of the system to be installed, altered, repaired, or exten- ded. The application shall also show the present or proposed location of water sup- ply facilities and water supply piping, and the name of the person, firm, or corpora- tion who is to install the sewage disposal system and shall provide such further in- formation as may be required by the Coun- cil. SECTION VII ADMINISTRATION The Council shall assign responsibility for administration of this ordinance to a qualified Administrator. This qualified Administrator shall have atten- ded at least one Home Sewage Workshop conducted by the University of Minnesota Extension Service and shall periodically familiarize himself/herself with in- novative technology. The administrator shall have the authority to waive any ap- plication requirement for altering or repairing an existing sewer system if it is determined that requirement of such wi11 be an unnecessary hardship. SECTION VIII SITE EVALUATION Proposed sites for all private sewage disposal systems shall be explored, evaluated. and reported on forms as provided for by the City. Site investiga- tion shall be made by a site evaluator. The site evaluator's report, signed and sealed by him. shall indicate assessment of the suitability of the site and the site's soils for sewage disposal. System type and design should be ascertained and reported by him following the terms of the Medina Sanitary Code. Soils shall be iden- tified by strata and the textural classes of the strata defined according to an accep- ted classification system. The findings shall be supported with: 1. A location plan, with the proposed lots, lines and streets clearly marked. 2. A log of all soil exploration including a description of the various strata encoun- tered. 3. Slopes of the land area in question. 4. Groundwater conditions (including in- dications of seasonal groundwater fluctua- tions) . 5. The design and type of system selec- ted according to the Medina Sanitary Code (including the amount and type of fill re- quired or any special design factors which should be considered). 6. Distances to all surface waters, wells, springs, or other surface waters within one hundred fifty (150) feet of the proposed disposal area. 7. Results of at least three (3) percola- tion tests and one (1) soil boring perfor- med according to testing procedures described in Section IX. Soil Scientists shall also describe the soils at the site in accordance with the standards of the National Cooperative Soil Survey and the Hennepin County Soil Sur- vey - 1974. SECTION IX SOIL BORINGS AND PERCOLATION TESTS A. General Soil boring and percolation tests shall be performed under the supervision of the site evaluator. The location of these tests shall be indicated on the preliminary plot and certified by the person conducting the test. B. Soil Boring Tests and Soil Investiga- tion Pits Sufficient borings shall be made to por- tray adequately the character of the soil, groundwater levels (seasonal high water table) and depths to bedrock. The borings shall be distributed as uniformly as possi- ble and their location shall be shown on the location plan. Table 1 Number of Soil Investigation Pits or Bor- ings Daily Volume of Sewage - Less Than 500 Gallons - Number of Pits required 1 and/or Number of Borings required 1. For Each Additional 500 Gallons - Num- ber of Pits required 1 and/or Number of Borings required 1. The soil borings on sites shall be to a depth of five feet or the ground -water table. within the proposed soil absorption area. The report of the test shall indicate the slope. the soil characteristic by strata. and maximum groundwater elevation. The minimum diameter of the borings ;hall be four inches. SECTION X PERCOLATION TES1 PROCEDURE A. Number and Location of Tests Three (3) or more tests shall be made in separate test holes spaced uniformly over the proposed absorption field site and their location clearly marked on a map of the area. B. Type of Test Hole A hole with horizontal dimensions of four (4) to twelve (12) inches and vertical sides shall be dug or bored to the depth of the proposed absorption trench. The holes may be bored with an auger of not less than four (4) inches in diameter. C. Frozen Soils Percolation test shall not be performed in frozen soil or frost conditions. D. Preparation of Test Hole The bottom and sides of the hole shall be carefully scratched with a knife blade or sharp pointed instrument to remove any smeared soil surfaces and to provide a natural soil interface into which water may percolate. A11 loose material shall be removed from the hole and two (2) inches of coarse sand or fine gravel shall be ad- ded to protect the bottom from scouring and sediment. E. Saturation and Swelling of the Soil The hole shall be carefully filled with clear water to a minimum depth of twelve (12) inches over the gravel. Water shall be kept in the hole for at least twelve (12) hours, and preferably overnight, by refill- ing if necessary, or by supplying a surplus reservoir of water, such as in an automatic siphon. In sandy soils contain- ing little or no clay, the swelling procedure shall not be required and the test may be made as described under Item d.5 (c) after the water from one filling of the hole has completely seeped away. F. Percolation Rate Measurement With the exception of sandy soils, per- colation rate measurements shall be made on the day following the procedure described under Item D and E above and. as follows: A percolation test data sheet should be kept and submitted for each test. 1. If water remains in the test hole after the overnight swelling period, the depth shall be adjusted to approximately six (6) inches over the gravel. From a fixed reference point, the drop in water level shall be measured over a thirty (30) minute period. This drop shall be used to calculate the percolation rate. 2. If no water remains in the hole after • he overnight swelling period. clear water ,shall be added to bring the depth of water r.n the hole to approximately six (6) inches over the gravel. From a fixed reference point. the drop in water level shall be measured at approximately thirty (30) minute intervals for four hours, refilling six (6) inches over the gravel. if necessary. The drop that occurs during the final thirty (30) minute period shall be used to calculate the percolation rate. 3. In sandy soils or other soils in which the first six (61 inches of water seeps away in less than thirty (30) minutes. the time interval between measurements shall be taken as ten (10) minutes and the test shall be run for one (1) hour. The drop that occurs during the final ten (l0) minutes shall be used to calculate the per- colation rate. SECTION XI SITE CRITERIA FOR SYSTEMS ENCOMPASSED BY THIS ORDINANCE This code allows for the standard sub- surface soil absorption systems. Necessary minimum conditions for the proper functioning of this system are listed below. A. Standard Subsurface Soil Absorption System 1. Percolation Rate - The percolation rate must be faster than 60 minutes per inch and less than 0.5 minutes per inch. 2. Depth to groundwater or seasonally saturated horizons - for proper functioning of this system. the minimum depth to groundwater or seasonally saturated con- ditions shall be more than five (5) feet. 3. Flooding Hazard - there must be no hazard of flooding in the area where these systems are installed. 4. Slope - The land slope in the area proposed for the soil absorption field shall not be greater than 12 percent. 5. Depth to bedrock or other impervious materials - the depth to impervious materials must be more than six (6) feet. SECTION XII SOIL SERIES Soil series which in most cases will be considered suitable for installation of the systems discussed in the design manual. A. The following soil series may be suitable for installation of conventional subsurface soil absorption system described in the design manual. HbB, HbC, HbB2, HcC2, HeB, WC, HIB, H1C, LrB, LrC, LsB2, LsC2. B. The following soil series and other associated land generally have such severe limiting conditions that no conven- tional soil absorption sewage disposal systems will adequately treat the effluent, therefore, no development requiring the provision of an on -site sanitary sewage disposal system shall be allowed on these soils except as provided in Section XVI. LtB NeB • EnB, EnC, ErB2, ErC2 D1B, DIA Du KkB, KkC, K1Ca LmB AnB, AnC BsB, BsC DnA, DnB, DnC Dp EtA, EtB, EtC Hayden and Lester with percolation rate faster than 60 minutes Ca Co HbD, HbF, HcD2, HdF D1C HeD, HeF, HID, HIE Mt Sh LrD, LrE, LsBz KkD, KkE, K1D2 EnD, EnE, ErD2, EsF EtD Ha SECTION XIII SEWAGE TANKS A. Capacity 1. Residential Units Each residential unit shall be served by two septic tanks. The liquid capacity of a septic tank serving a dwelling shall be based on the number of bedrooms contem- plated in the dwelling served and shall conform to capacities given below (see definition of Bedroom and General Provi- sion H). Table 2 Number of Bedrooms - Tank Liquid Capacities (Gallons) respectively: 2 or less 750 3 1,000 4 1,250 5 or 6 1,500 7, 8, or 9 2,000 For ten (10) or more bedrooms, the sep- tic tank shall be sized as a non-residential unit (See Section 3.b). 2. Non -Residential Units The liquid capacity of a septic tank serv- ing an establishment other than a dwelling shall be sufficient to provide a sewage detention period of not less than 36 hours in the tank for flows less than 1,500 gallons per day, but in no instance shall the liquid capacity be less than 750 gallons. For flows greater than 1,500 gallons per day, the minimum liquid capacity shall equal 1,125 gallons plus 75 percent of the daily sewage flow rate, which shall be deter- mined by measurement or estimated from data provided by the Agency. B. Location 1. The sewage tank shall be placed so that access is convenient for the removal of liquids and accumulated solids. 2. The sewage tank shall be placed on firm and settled soil capable of bearing the weight of the tank and its contents. 3. Sewage tanks shall be set back the following distance from the features given below. Table 3 Feature - Minimum Setback Distances (Feet) respectively: Water Supply We11 a. 50 feet deep or less 100 b. 50 feet deep or more 50 Buried Pipe Distributing Water Under Pressure 10 Buildings 10 Large Trees 10 Property Line 10 Table 4 Feature Minimum Setback Distances tFeet) respectively: Natural Environment for each individual unit Lakes and Streams 150 4. Trench and bed size shall be as set Recreational Development forth in Table 5. Lakes and Rivers 75 General Development Lakes and Streams 50 C. Aerobic Tanks Aerobic tank treatment systems shall comply with the following design require- ments: The treatment system including each in- dividual unit or compartment shall be easily accessible for inspection and main- tenance and shall be provided with secured covers. The raw sewage flow from the dwelling shall be intercepted by a trash trap prior to its entering the aeration compartment. The trash trap shall have a net holding capacity of not less than 20 percent of the average daily flow. The invert level to the trap shall be above the liquid level and dis- charge directly into the trap. The outlet from the trap to the aeration compart- ment shall be deep baffled or equipped with a tee or long ell. The trash trap shall be readily accessi- ble for inspection and effective cleaning and shall be so constructed as to prevent unauthorized entry. The aeration compartment shall have a minimum holding capacity of five hundred gallons or one hundred twenty gallons per bedroom, whichever is greater. The method of aeration shall be accom- plished by mechanical aeration, diffused air, or both. The method used shall main- tain aerobic conditions at all times. D. The settling compartment shall have a minimum net holding capacity equal to twenty percent of the volume of the aera- tion compartment. The design shall provide for effective settling and con- tinuous return of settled sludge to the aeration compartment. E. A minimum one year warranty and an initial two year service contract which specifies regular inspection calls and ef- fluent quality checks shall be provided as a part of the purchase agreement. F. A11 other features of the aerobic tanks not specifically mentioned above shall comply with National Sanitation Foundation Standard No. 40. SECTION XIV STANDARD SOIL AB- SORPTION SYSTEM A. General Final treatment and disposal of sewage tank effluent shall be by means of soil treatment and disposal. B. Sizing 1. The required soil treatment area shall be determined by number of bedrooms (see definition of "Bedroom" and General Provision H for dwellings and definition of "water use" for other establishments). 2. The minimum soil treatment area re- quired for any dwelling shall provide for at least two bedrooms. 3. The minimum soil treatment area re- quired for multiple residential units shall consist of the sum of the areas required Percolation Rate in Minutes Per Inch Faster than (d) 1zto5 (e) 6 to 15 16 to 30 31 to 45 46 to 60 Slower than 60 (f Per gallon of Waste per day lc 0.83 1.27 1.67 2.00 2.20 Table 5 (a) Table is based on a sewage flow of 150 gallons per day per bedroom. (b) In every case sufficient area shall be provided for at least two bedrooms in residential units. (c) When treatment system design is based on gallons of water per day, the re- quired treatment area may be reduced for trenches only, by the following percen- tages: 20 percent for 12 inches of filter material below the distribution pipe; 34 percent for 18 inches; and 40 percent for 24 inches. . The filter material shall com- pletely encase the disposal pipes to a depth of at least one inch. (d) Soil is unsuitable for standard system if percoiation rate is faster than l z minute per inch. See sections 17-18 for alternative systems. (e) Consider alternative sewage treat- ment units for soils with this percolation rate range. See Sections 17-18 for alter- native designs. (f) Soil is unsuitable for standard system if percolation rate is slower than 60 minutes per inch. See Sections 17-18 for alternative systems. C. Location Any soil treatment area shall be set back the following distances from the features given below: Table 6 Feature - Setback Distance in Feet respectively: Water supply well less than 50 feet deep and not encountering at least 10 feet of im- pervious material. -100 Any other water supply well or buried water suction pipe - 50 Buried pipe distributing water under pressure - 10 Building - 20 Property Lines - 10 Natural Environment Lakes and Streams - 150 Recreational Development Lakes - 75 General Development Lakes and Streams - 50 Trees - 10 SECTION XV SEPARATE TOILET --WASTE GREYWATER SYSTEMS Required Soil Treatment Area in Square Feet Per bedroom (a) (b) Beds Trenches Depth of Filter Material Below Distribution Pipe (c) In Inches 6 12 18 24 125 125 190 190 250 250 300 300 330 330 100 150 200 240 265 85 125 165 200 220 75 115 150 180 200 A. General 1. A toilet waste treatment device shall be used in conjunction with a greywater system. 2. In all cases, only toilet wastes shall be discharged to toilet waste treatment devices. Greywater or garbage shall not be discharged to the device except as specifically recommended by manufac- turer. B. Toilet -Waste Treatment Devices 1. Toilet -waste treatment devices shall be considered as one of two types; 1) privies, and 2) other devices, including but not limited to; incinerating, composting, biological, chemical, recirculating or holding toilets. 2. Type 1- Privies a. Pit privies shall not be installed where the bottom of the pit is less than four (4) feet above the water table. A vault privy shall be used in areas of high groundwater. The vault of a vault privy shall be constructed in the same manner as a septic tank. b. Privies shall be set back from surface waters the same distance required for buildings and from property lines and water supply wells the same distance as required for soil treatment areas. c. Pits or vaults shall be of sufficient capacity for the residence they serve, but shall have at least 50 cubic feet of capacity. d. The sides of the pit shall be curbed to prevent cave-in. e. The superstructure shall be construc- ted so as to be easily cleaned, and it shall be insect proof. The door and seat shall be self -closing. All openings including vent openings shall be screened. f. Privies shall be adequately vented. g. When the pit is filled to within one foot of the top, the solids shall be removed or a new pit shall be constructed. The abandoned pit shall be filled with clean earth and slightly mounded to allow for settling. Removed solids shall be disposed of by burial, or by land application in ac- cordance with agency guidelines for sludge disposal and all local ordinances and codes. h. All liquids and soils removed from a vault privy shall be treated and disposed of by burial or by application in accor- dance with the Agency's sludge disposal guidelines. 3. Type II - Other Devices a. Other devices may be used when reasonable assurance of performance is provided. b. All Type II devices shall be vented. c. All electric. gas and water connec- tions to a Type II device shall conform to all local ordinances and codes. d. Operation and maintenance of all Type II devices shall follow the manufac- turer's recommendations. 4. All materials removed from a Type I or II toilet waste treatment device, in- cluding but not limited to; ashes, compost. and all solids and liquids, shall be disposed of in a public sewage system or by burial or by land application in accordance with the agency's sludge disposal guidelines and all local ordinances and codes. C. Greywater System 1. Plumbing a. The drainage system in new systems shall be based on a pipe diameter of two inches to prevent installation of water flush toilets. There shall be no openings or connections to the drainage system, in- cluding floor drains larger than two inches in diameter. For repair or replacement of an existing system, the existing drainage system may be used. b. Toilets or urinals of any kind shall not be connected to the drainage system. Toilet waste or garbage shall not be dis- charged to the drainage system. c. Garbage grinders shall not be connec- ted to the drainage system. 2. Building Sewer The building sewer shall meet all re- quirements of sewage system design ex- cept that the building sewer for a greywater system shall be at least two in- ches in diameter. 3. Sewage Tank Greywater septic tanks shall meet all sewage tank requirements except that the liquid capacity of a greywater septic tank serving a dwelling shall be based on the number of bedrooms contemplated in the dwelling served and shall be at least as large as the capacities given below in Table 7. Table 7 Number of Bedrooms - Tank Liquid Capacity (gallons) respectively. 2 or'less or hand pump 300 3 500 4 625 5or6 750 7, 8, or 9 1,000 4. Distribution and Dosing Distribution and dosing of greywater shall meet all requirements of the sewage system design. 5. Final Treatment and Disposal a. Standard System A standard greywater system shall meet all requirements of sewage system design except that the required treatment area shall be calculated as in Table 8. Table 8 Percolation Rate Minutes Per Inch 'zto5 (c) (d) 6 to.15 16 to 30 31 to 45 46to60(e) SECTION XVI OTHER SYSTEMS A. General On 5 acre lots or larger. or where it has been found that an existing system is fail- ing. this code allows the installation of one of two alternative systems. The two general types of systems are the in- novative subsurface absorption systems (including shallow trenches and equal dis- tribution system) ; two types of innovative mound systems to be installed on soils with slow permeability or high groundwater problems. B. Conditional Permit Other systems shall be employed only after the issuance of a zoning ordinance conditional use permit provided the following: 1. Reasonable assurance of perfor- mance of such system is presented to the city. 2. The engineering design of such system is first approved by the city. 3. There is no discharge to the ground surface or to surface waters. 4. Treatment and disposal of wastes is in such a manner so as to protect the public health and general welfare. 5. Such systems comply with all ap- plicable requirements of these standards and with all local codes and ordinances. C. System Review and Monitoring All permitted special systems shall an- nually furnish the Administrator with an inspection report assuring proper system operation by June 30. D. System Failure Any failing system violating the condi- tions of the special permit shall cease operation and special permit shall be revoked. E. Site Criteria For Innovative Subsur- face Soil Absorption Systems 1. Percolation Rate - The percolation rate must be faster than 60 minutes per inch and slower than 0.5 minutes per inch. 2. Depth to groundwater - Depth to groundwater or seasonally saturated area must be greater than three feet from the bottom of the trench. 3. Flood Hazard - There must be no flooding hazard. 4. Slope - The land slope in the area be- ing considered for the installation of the system must not be greater than 12%. 5. Position on the landscape - The system shall be installed on level areas, on top of rises on convex slopes, on sides of rises on plane. The systems shall not be installed in depressions, swales or drainage -ways, and shall maintain a 50' setback from lot lines. Required Trench Bottom Area Per Residence Number of Bedrooms 2 3 4 5 6 90 109 127 146 165 137 166 195 224 253 180 218 257 295 333 216 262 307 353 398 238 288 338 388 438 F. Site Criteria for Innovative Mound Systems 1. Percolation Rate - The percolation rate in 12 inches or more of natural _sur-' face soil shall be faster than 60 minutes per inch and the percolation rate in subsoil and/or substratum shall be faster than 120 minutes per inch. 2. Depth to groundwater - The depth to groundwater shall be greater than 3 feet if the percolation rate is 60 to 120 minutes per inch and 2 feet with a percolation rate of 30 to 60 minutes per inch. 3. Flood Hazard - There shall be no hazard of flooding within the area con- sidered for installation of the system. 4. Slope - The land slope in the area be- ing considered for installation of the system shall not be greater than 6%. 5. Position on the landscape - The system shall be installed on level areas; such as the top of mounds and the level planes of stepped slopes. The systems shall not be installed in depressions; swales, or drainageways, and shall main- tain a 50' setback from lot lines. G. The following soil series may be suitable for installation of an innovative system described in the design manual LtB Hayden and Lester NeB percolation faster than 60 minutes EnB, EnC, ErB2, ErC2 D1B, D1A Du KkB, KkC, K1CA LmB AnB, AnC BsB, BsC DnA, DnB, DnC Dp EtA, EtB, EtC H. The following soil series and other associated land generally have such severe limiting conditions that no soil ab- sorption sewage disposal systems will adequately treat the effluent, therefore no development requiring the provision of an on -site sanitary sewage disposal system shall be allowed on these soils. Ca Co HbD, HbF, HcD2, HdF D1C HeD, HeF, H1D, H1E Mt Sh LrD, LrE, LsBz KkD, KkE, K1D2 EnD, EnE, ErD2, EsF EtD Ha Ma SECTION XVII INSPECTION The Administrator shall make such in- spection or inspections as are necessary to determine compliance with this or- dinance. No part of the sewage disposal system shall be covered until it has been inspected and accepted by the Ad- ministrator. It shall be the responsibility of the applicant for the permit to notify the Administrator that the job is ready for inspection or reinspection, and it shall be the duty of the Administrator to make the indicated inspection within twenty-four (24) hours after such notice has been given. It shall be the duty of the owner or occupant of the property to give the Ad- ministrator free access to the property at reasonable times for the purpose of mak- ing such inspections. Upon satisfactory completion and final inspection of the sewage disposal system, the Ad- ministrator shall issue to the applicant a certificate of approval. If upon inspection, the Administrator discovers that any part of the sewage dis- posal system is not constructed in accor- dance with the minimum standards provided in this ordinance, he shall give the applicant written notification describ- ing the defects. The applicant shall pay an additional fee for each reinspection that is necessary. The applicant shall be respon- sible for the correction or elimination of all defects, and no sewage disposal system shall be placed or replaced in service until all defects have been corrected or eliminated. SECTION XVIII DESIGN AND IN- STALLATION STANDARDS A11 system installations, alterations and repair shall be in conformance with the Medina Sewage Treatment Design Manual for system materials, design and con- struction standards. The Medina Sewage Treatment Design Manual shall be on file with the City Administrator. SECTION XIX MAINTENANCE At least once a year the owner of any septic tank or his agent shall measure or arrange for measurement of the depth of sludge and scum in such septic tank. When, as a result of such measurement, the top of the sludge layer in the tank or any compartment of the tank is found to be less than twelve (12) inches below the bottom of the outlet baffle or submerged pipe. or if the bottom of the scum layer is within three (3) inches of the bottom of the 'septic tank outlet baffle or submerged pipe, the owner or agent shall arrange for the removal and sanitary disposal of sludge and scum from the tank; provided that such requirement for measuring shall be waived for any septic tank which is cleaned as indicated at least once each calendar year. It shall be unlawful to operate a septic system which does not meet the requirements of this Section. SECTION XX ANNUAL INSPECTIONS Each owner of property containing an innovative sewage disposal system shall. within twelve (12) months from and after the date of the adoption of this ordinance. cause said system to be inspected by a person, firm, or corporation duly licensed by the City pursuant to Section 5 of this or- dinance and yearly thereafter shall. within said twelve (12) month period. sub- mit to the City Clerk a written statement showing the date upon which inspection was completed, the name and address of the person, firm or corporation by whom such inspecting was completed, and a report of finding of said inspection. SECTION X\I ENFORCEMENT Non -conforming systems shall be issued orders requiring maintenance, repair. alteration or replacement. Systems found to be non -conforming due to location or construction shall be located and ,or made conforming within one calendar year from the date of the order. Systems found to be non -conforming due to failure or pollution hazards shall have remedial action re- quired within a reasonable period of time as follows: Septic tanks or systems found to be clogged. overflowing, leeching, or otherwise discharging pollutants shall be pumped within 48 hours and thereafter as needed and the system shall be repaired, altered. or replaced within 90 days. SECTION XXII OBJECTIVES The objectives of this ordinance are to provide adequate and safe methods of sewage disposal and to prevent the con- tamination of any existing or future water supply by any existing or future sewage disposal system or both. SECTION XXIII PENALTIES Any person, firm, or corporation violating any of the provisions of this or- dinance shall be guilty of a misdemeanor, and upon conviction thereof shall be fined in an amount not to exceed five hundred (500) dollars or imprisoned for a time not to exceed ninety (90) days, or both. Each day that any violation is continued shall constitute a separate offense. SECTION XXIV LIABILITY OF CITY LIMITED This ordinance shall not be construed to relieve or lessen the responsibility or liability of any person, firm, party, partnership, or corporation owning, operating, controlling, or installing any wells or water supply systems for damages to persons or property caused by any defect therein, nor shall the City be held as assuming such liability by reason of the inspection authorized herein or cer- tificate of inspection issued as herein provided. SECTION XXV VARIANCES The City Council may permit variations from the requirements of this ordinance of the applicant demonstrates by evidence that the following qualifications are met: A. Because of the particular physical characteristics, shape, topographical con- ditions, hydrological conditions, or soil conditions of the specific lot, a particular hardship to the applicant would result, as distinguished from an inconvenience, if the strict letter of the regulations were to be carried out. B. The conditions upon which the ap- plication for a variance is based are uni- que to the lot for which the variance is sought. and are not generally common to other similar property in the city. C. Alleged hardship is caused by the re- quirements of the ordinance and has not been created or contributed to by the per- sons presently or formerly having an in- terest in the lot. D. The granting of a variance will not be detrimental to the public welfare or in- jurious to land, ground water or the use and enjoyment of other properties in the neighborhood. E. Conditions and Restrictions - The City Council, may impose conditions and restrictions upon the lot in the granting of a variance, so as to insure compliance with the regulations and the spirit and in- tent of this ordinance. SECTION XXVI BUILDING PERMITS No building permit shall be issued for any structure requiring an individual sewage disposal system unless an applica- tion and tests, as required by this or- dinance, for the premises involved have been filed with and approved by the City and all other provisions of this ordinance relative to said structure have been met. SECTION XXVII SEVERABILITY If any provision of this ordinance or the application thereof to any person or cir- cumstances is held to be invalid, such in- validity shall not affect other provisions of this ordinance or application of any other part of this ordinance which can be given effect without application of the in- valid provision. To this end the provisions of all sections, subsections or subdivisions herein and the various applications thereof are declared to be severable. SECTION XXVIII EFFECTIVE DATE This ordinance shall be effective follow- ing its passage and publication in accor- dance with the law. Adopted this 18th day of December, 1979 by the City of Medina. Thomas Anderson Mayor ATTEST: Donna Roehl Clerk -Treasurer Published in the Crow River News Wed- nesday Jan. 16, 1980.