Development means development as defined in the Municipal Government Act, R.S.A. 2000, c. M-26.

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1 PROCEDURE PRO-449 Title: Performance Requirements for Wastewater Treatment Systems Legal References: Provincial Act(s): Municipal Government Act Safety Codes Act Provincial Regulation(s): Safety Codes Council Alberta Private Sewage Systems Standard of Practice 2009 Council Resolution(s): Other: Procedure Category: Infrastructure & Operations Cross References: Supercedes: Strategic Plan/Vision: Policies: 430 -Performance Requirements for Wastewater Treatment Systems Procedures: Other: Rocky View County Servicing Standards Adoption Date: Effective Date: May 10,2011 Revision Date(s): Purpose: The purpose of this procedure is to provide Administration with alternatives for sewage disposal based upon three available options: 1. Regional Wastewater Treatment Systems & Connections 2. Communal Wastewater Treatment Systems 3. Private Sewage Treatment Systems (PSTS) Definitions: CCC means Construction Completion Certificate. County means Rocky View County. Decentralized Wastewater Treatment Systems consist of a communal system that collects typical wastewater strength effluent from multiple lots, conveys effluent to a wastewater treatment plant for treatment and discharges to an approved discharge location. Development means development as defined in the Municipal Government Act, R.S.A. 2000, c. M-26. Development area means those various areas of Lands within the County as set out in Schedule A. FAC means Final Acceptance Certificate. Master Servicing Strategy is a detailed analysis of servicing options, best possible locations and ultimate discharge strategies for wastewater for a defined service area. Odour Control Mechanisms means an air outlet discharging air that has been filtered/treated to remove/minimize human detectable odours with the use of UV light or other appropriate means. PRO-449 Page 1

2 Packaged Sewage Treatment Plant means a manufactured unit that is used to substantially improve the effluent quality beyond the quality of effluent expected of a septic tank that meets the requirements of BNQ and NFS/ANSI Standard 40 specifications. Private Sewage Treatment Systems provide on-site wastewater treatment and include septic tank and tile fields, treatment mounds, and packaged sewage treatment plants. Regional Wastewater Treatment Systems consists of a communal system that collects sewage from large developed or developing areas and conveys the sewage to a regional treatment facility. Transfer Agreement means an agreement supported by a Cost Feasibility and Sustainability Analysis that sets out the terms and timelines for the transfer of wastewater infrastructure and/or operational responsibility from one party to another. Typical Wastewater means wastewater that: a. 80% of the time has i) BOD 5 of less than 200mg/L, ii) TSS of less than 220 mg/l, and iii) oil and grease content of less than 50 mg/l, and b. does not exceed i) BOD 5 of 300 mg/l, ii) TSS of 350 mg/l, and iii) oil and grease content of 70 mg/l. Note: Assumed design peak daily flow of 340 L per person per day. 1. Design Requirements - The design of sanitary wastewater collection, treatment, and disposal systems shall favour providing a long service life, ease of maintenance, and ease of operation over initial start-up costs. Except where stated otherwise, all design criteria, materials, installation and testing shall be in accordance with the following: Rocky View County Servicing Standards. Standards and Guidelines for Municipal Waterworks, Wastewater, and Storm Drainage Systems in Alberta, as published by Alberta Environment. The City of Calgary Wastewater, Standard Specifications Sewer Construction. *Manhole coverings should not reference other Municipalities. Alberta Environmental Protection s Environmental Reference Manual for Review of Subdivisions in Alberta. Alberta Private Sewage Systems Standard of Practice. The Alberta Private Sewage Systems Standard of Practice sets out design standards, installation standards and material requirements for on-site private sewage systems handling less than 25 cubic metres (5,500 Imperial gallons) sewage volume per day. A Model Process to Guide Municipal Consideration of Subdivision and Developments using Private Sewage Treatment Systems (Alberta Municipal Affairs and the Alberta Association of Municipal Districts and Counties). For communal systems the experience and professional knowledge of the Developer s Engineering Consultant who is ultimately taking responsibility through their professional endorsement of the sanitary wastewater design. Also, it is the responsibility of the Engineer certifying the design of the system to ensure that upon final acceptance of the development by the County, the future public responsibilities for maintenance fall within normal, reasonable and tolerable levels. Other policy, standards or guidelines as deemed applicable by the County. PRO-449 Page 2

3 2. Review of Wastewater Treatment Options - A proper and detailed review of wastewater treatment options is required for any proposed development. Existing sanitary wastewater disposal sites should be investigated for a central hook-up if such capacity is available. 3. Cost Feasibility And Sustainability - A key component to the County s review of proposed wastewater treatment systems is the requirement for a Cost Feasibility and Sustainability Analysis report, to be provided by the development proponent. This report must outline the life-cycle cost of construction, operation, maintenance and replacement of proposed Wastewater Treatment Systems in the County. The report must be endorsed by a Consulting Engineer, reviewed by the County and if required, a 3 rd party review will be completed. The cost of preparing this report will be borne by the Developer. The County will use the report to determine the long-term financial feasibility and sustainability of proposed Wastewater Treatment Systems. The report should provide at a minimum the following: a. Guidance on timing of transfer to County b. Guidance on utility billing costs for connecting users c. Expandability of system to encompass present and/or future lands and users d. Identification of what is an affordable utility billing rate for the proposed Development e. Identification of minimum number of connecting users to achieve affordable utility billing rates 4. County-specific Requirements for Wastewater Treatment - In addition to the standards, guidelines and documents listed above, the County has developed its own set of specific requirements as listed below. a. REGIONAL WASTEWATER TREATMENT SYSTEMS Design and Siting 1. Regional Wastewater Treatment Systems and connections must follow the guidelines and recommendations set out in the applicable County Master Servicing Strategy (if available). 2. All regional systems will be required to be on public utility lots where the title is held by the County and the Developer shall be responsible for ensuring they meet or exceed all municipal and provincial (Alberta Environment) guidelines and design requirements. Discharge locations and treatment methods will need to meet or exceed Alberta Environment and Municipal guidelines and regulations. System Design and Approvals 3. When a Regional Wastewater Treatment System is being considered, the documents listed in Section 1 shall be relied upon for minimum design requirements. 4. These minimum guidelines may not be applicable to every situation and good engineering design practices of a higher standard may be required to ensure the proper treatment and disposal of the wastewater in specific situations. 5. All designs of Regional Wastewater Treatment Systems require Alberta Environment permits and licenses for construction and operation. 6. The proponent of development is responsible for all necessary approvals and for ensuring that the design meets all requirements of all Provincial and other regulatory bodies. 7. A Regional Wastewater Treatment System shall incorporate a membrane bioreactor filtration system capable of treating sewage, complete with the membrane skids, bioreactor tanks, all pumps, blowers, integral piping, valves, instrumentation and controls to treat the required volume of wastewater. PRO-449 Page 3

4 8. Currently Alberta Environment requires a 300 metre setback from a treatment plant to any residential dwelling however, Subdivision Authority may grant relaxation for setbacks subject to Alberta Environment consent. Any setback relaxations requested by the Subdivision Authority must be a minimum of 20 metres from any residential dwelling to the treatment plant and be supported by an Emergency Response Plan and Operations Response Plan that includes odour, nuisance and sound attenuations. East Rocky View Wastewater Transmission Main 9. In circumstances where a connection to the East Rocky View Wastewater Transmission Main is being considered, the Developer will need to contact Rocky View s Engineering Services for an appointment to address lateral lift station requirements, connection locations, levy requirements, and other pertinent items. b. DECENTRALIZED WASTEWATER TREATMENT SYSTEMS Design and Siting 1. Decentralized Wastewater Treatment Systems and connections shall follow the guidelines and recommendations of the County s Master Servicing Strategy (if available). 2. All Decentralized Wastewater Treatment Systems will be required to be on public utility lots where the title is held by the County and the Developer shall be responsible for ensuring they meet or exceed all municipal and provincial (Alberta Environment) guidelines and design requirements. Discharge locations and treatment methods will need to meet or exceed Alberta Environment and Municipal guidelines and regulations. 3. Discharge locations and treatment methods will need to meet or exceed Alberta Environment and Municipal guidelines and regulations. System Design and Approvals 4. When a Decentralized Wastewater Treatment System is being considered, the documents listed in Section 1 shall be relied upon for minimum design requirements. 5. These minimum guidelines may not be applicable to every situation and good engineering design practices of a higher standard may be required to ensure the proper treatment and disposal of the wastewater in specific situations. 6. All designs of Decentralized Wastewater Treatment Systems require Alberta Environment permits and licenses for construction and operation. 7. The proponent of development is responsible for all necessary approvals and for ensuring that the design meets all requirements of all Provincial and other regulatory bodies. 8. Decentralized systems that Rocky View County presently allow are ECOfluid USBF, BioNest and ORENCO systems and must meet, as a minimum: i. 15 mg/l Total Suspended Solids (TSS) and ii. 15 mg/l Chemical Biological Oxygen Demand (CBOD) or more stringent requirements as deemed by Alberta Environment. 9. These systems must have remote monitoring capability 24 hours per day and 7 days per week. PRO-449 Page 4

5 10. Currently Alberta Environment requires a 300 metre setback from a treatment plant to any residential dwelling however, Subdivision Authority may grant relaxation for setbacks subject to Alberta Environment consent. Any setback relaxations requested by the Subdivision Authority must be a minimum of 20 metres from any residential dwelling to the treatment plant and be supported by an Emergency Response Plan and Operations Response Plan that includes odour, nuisance and sound attenuations. c. PRIVATE SEWAGE TREATMENT SYSTEMS (PSTS) Private Sewage Treatment Systems Testing Requirements for Subdivision Approval 1. The County is following the Model Process Reference Documents. In some cases, the County will refer directly to the Alberta Private Sewage Systems Standard of Practice Handbook for Private Sewage Treatment Systems (PSTS) standards. If the Model Process assessment identifies additional improvements to be implemented at the lot development stage then the County will require the Developer to enter into a form of Development Agreement and register it on title. This will notify future land owners, installers and Safety Codes Officers of the necessary additional improvements. Copies of the Model Process Reference Documents can be obtained at the AAMD&C Website. Permitting and Siting of PSTS 2. A permit is required prior to the installation of a PSTS. The permit is available through the County s Building Services and requires the work be completed by a certified installer and must meet the requirements of the Safety Codes Act. Conventional PSTS systems can be installed on lots 4 acres and greater provided a proper site evaluation in accordance with the Model Process Reference Document or the Alberta Private Sewage Systems Standard of Practice has been completed. 3. The County does not support the use of sewage holding tanks for residential subdivisions or developments. 4. For residential developments, packaged sewage treatment plant methods meeting the Bureau de Normalisation du Quebec (BNQ) standards for onsite residential wastewater treatment are encouraged by the County. The operation and maintenance is critical and the responsibility of the PSTS lies with the landowner. The reports derived from the testing procedures of the Model Process should be made available to the future landowners. Packaged Private Sewage Treatment Systems 5. For residential developments relying on PSTS, where lot sizes are equal to, or greater than, 1 acre but less than 4 acres, the County requires the use of Packaged Sewage Treatment Plants for private sewage disposal. In addition to the requirements described in this Policy, the site selection, design, installation, operation and maintenance of these systems must be in accordance with Provincial guidelines, standards, and regulations; and must meet, as a minimum: i. 15 mg/l Total Suspended Solids (TSS) and ii. 15 mg/l Chemical Biological Oxygen Demand (CBOD). Separation Distances shall be in accordance with the Alberta Private Sewage Systems Standard of Practice. 6. Packaged sewage treatment systems come in many forms and variations but typically must meet National Sanitation Foundation (NSF 40) standards. This is a U.S. standard; however, many of the systems meeting this requirement have not been proven effective in a Canadian environment. This has been addressed with the introduction of the BNQ standard. This standard applies 6 months of cold weather winter testing on top of the NSF 40 test procedure. The BNQ standard is the County s requirement for packaged sewage treatment plants meeting BNQ standard satisfied requirements of standard NQ , Class III and Class V. PRO-449 Page 5

6 7. Wastewater Strength - A packaged sewage treatment plant shall not receive wastewater having a strength that exceeds typical wastewater unless it can be demonstrated the packaged treatment plant has the capacity to treat the organic loading of the wastewater to achieve the effluent quality required by these standards. 8. Treatment Capacity - A packaged sewage treatment plant used in an on-site wastewater treatment shall have a rated treatment capacity of 1.5 times the expected daily peak volumes 9. Service Access Not Buried - Packaged sewage treatment plant access openings shall not be buried and shall be located at a height above the surrounding landscape that ensures surface water will drain away from the access opening to ensure an access opening for required maintenance. 10. Access Openings Equipped with Lid/Cover - Packaged sewage treatment plant access openings shall be equipped with a secure lid or cover to increase safety by preventing unauthorized or accidental entry into the access opening. Acceptable protective measures include, but are not limited to, a padlock, a cover that can only be removed with tools, or a cover having a minimum weight of 29.5 kg (65 lbs). All man way access openings shall be insulated to provide the equivalent of an R-8 insulation value. 11. Base for Package Sewage Treatment Plant - The bottom of an excavation for a packaged sewage treatment plant shall provide a uniform base to support the tank in a level position and meet the manufacturer s installation instructions. A tank must have a stable base so it will not settle, shift, or crack after installation. 12. Insulation of Tank - A packaged sewage treatment plant that has less than 1.2 m (4 ft) of earth cover to protect it from freezing conditions shall be insulated to provide the equivalent of an R-8 insulation value over the top and sides of the tank to a minimum depth of 1.2 m (4 ft) below grade or insulated in some other acceptable manner to achieve a level of protection from freezing that is equivalent. 13. The County recommends the use of sewage holding tanks for industrial, commercial and institutional land uses when it is not feasible to connect to a Regional or Decentralized systems. The County does not permit the use of PSTS for any purpose other than typical wastewater strength and volume wastewater treatment and disposal. PRO-449 Page 6