Engineering—Reports, Plans, and Specifications

PURPOSE: This rule provides the minimum criteria for the preparation of engineering reports and facility plans and specifications related to the design of wastewater systems. This rule is to be used with rules 10 CSR 20-8.110 through 10 CSR 20-8.210 for the planning and design of a wastewater treatment facility. It does not address all aspects of design, and the design engineer may refer to other appropriate reference materials so long as these minimum standards set forth in this rule are met. (1) Applicability. Engineering reports and facility plans and specifications shall be prepared based on criteria contained in this rule, published standards, applicable federal and state requirements, standard textbooks, current technical literature, and applicable safety standards. In the event of any conflict between the above criteria, the requirement in this rule shall prevail. (A) This rule shall not apply to treatment units covered in 10 CSR 20-8.300. (B) This rule shall not apply to treatment units covered in 10 CSR 20-8.500. (2) General. All documents submitted to the Missouri Department of Natural Resources (department) for the purpose of complying with this rule shall be prepared, signed, sealed, and dated by a Missouri registered professional engineer. (A) Submittal. The design engineer must submit a project engineering report or facility plan to the department and receive department approval prior to submitting permit applications, plans, specifications, and fees. (B) Engineering Reports or Facility Plans. 1. Engineering reports must be completed for projects involving collection systems, pumping stations, and force mains. 2. Facility plans must be completed for projects involving wastewater treatment facility projects and projects receiving department funding through the grant and loan programs under 10 CSR 20-4, Grants and Loans. (C) Approval. Engineering report or facility plan approval does not authorize construction. (3) Hydraulic and Organic Waste Load. (A) Existing Systems shall— 1. Use actual flow data that accurately represent the average and peak flows to calculate projections for hydraulic capacity; 2. Include contributions from existing upstream combined sewers that will affect interceptor sewers and treatment facilities; 3. Use actual data that accurately represent organic waste load to calculate projections for organic capacity; and 4. Include documented hydraulic and organic waste load contributions of industrial sources in the calculations of projected capacity. (B) New Collection and Wastewater Treatment Systems. 1. Hydraulic capacity for wastewater facilities and new collection systems. A. Flow estimates for the design average flow and design peak hourly flow, including origin of the flow estimates and any assumptions, shall be identified. B. Peaking factor. The average design flow value shall be used in conjunction with a peaking factor from the following Equation 110-1, included herein. Equation 110-1. Ratio of peak hourly flow to design average flow. Peaking Factor = Q Peak Hourly / Q Design Avg = (18 + √P) / (4 + √P) Where: Q Peak Hourly = design peak hourly flow Q Design Avg = design average flow P = Population in thousands C. Where the new collection system is to serve existing development, the likelihood of inflow and infiltration (I/I) contributions from existing service lines shall be evaluated. 2. Organic Waste Load. Organic waste load estimates shall be identified for all contributing parameters such as the design average five (5)-day Biochemical Oxygen Demand (BOD5). (C) Drinking Water Use Records. Facilities proposing drinking water usage as the basis for design average flow must provide at least one (1)-year of drinking water use records in the following form: 1. A minimum of twelve (12) continuous months of drinking water use records for facilities that discharge year-round; or 2. A minimum of continuous daily water use records during the entirety of an operating season for facilities having critical operational schedules (e.g., recreational areas, campuses, and industrial facilities). (D) Re-Rating a Wastewater Treatment Facility. A wastewater treatment facility owner must request department review and approval when proposing to re-rate an existing wastewater treatment facility’s current design hydraulic capacity or organic waste loading. An engineering re-rating analysis must demonstrate the wastewater treatment facility can reliably operate at the proposed re-rated loading rate. The re-rating analysis shall include the following: 1. Hydraulic Capacity. Evaluate the annual average flow, the maximum monthly average flow, the maximum daily flow, and the ratio of the peak flow to annual average flow using the last five (5) years’ wastewater treatment facility. Include all calculations and assumptions. A. Calculate the design average flow using the wastewater treatment facility’s average annual flow plus one (1) standard deviation for a wastewater treatment facility that will not be affected by future growth; or B. Calculate the design average flow using the anticipated changes from the existing flow for a wastewater treatment facility that will be affected by future growth. 2. Organic Waste Load. Evaluate the design organic waste loading based on the average daily organic load. A. Include the data from the analyses of at least three (3) twenty-four (24)-hour composite samples of the influent wastewater per week, taken during days with representative flow, for a period of at least three (3) months during both wet and dry weather conditions; B. Include sample data of the following parameters unless monitoring of the parameter is not a requirement of the National Pollutant Discharge Elimination System (NPDES) permit: BOD5, Total Suspended Solids (TSS), ammonia, total nitrogen, and total phosphorus; C. Include the influence of hydraulic capacity evaluation from subparagraph (3)(D)1.A and B. of this rule; and D. Evaluate the size of each unit process to determine if they are appropriately sized to provide adequate treatment based on the re-rated design organic waste load. 3. Existing unit processes. Evaluate each unit process for its design and peak capacity. Normally one (1) unit process will be most restrictive in terms of design capacity. Include solids processing, handling, and storage in this analysis. 4. Compliance. Evaluate the proposed change of the facility’s ability to reliably and consistently comply with the NPDES permit effluent limitations and conditions. 5. Growth. Evaluate the system’s anticipated rate of growth. (4) Engineering Report. Engineering reports shall include the following: (A) Cover Page. Include a statement identifying the owner and continuing authority (refer to 10 CSR 20-6.010(2)(A)), a contact person for each (including phone number and address), and engineer in accordance with section (2) of this rule; (B) Problem Defined. Include a description of the existing system and an evaluation of the conditions and problems needing correction; (C) Hydraulic Capacity and Organic Waste Load. Establish the anticipated design average and design peak flows and organic loads for the existing and ultimate conditions. Include the basis of the projection reflecting the existing or initial service area, and the anticipated future service area. More detail on flow and organic waste load information and data needed for new and existing collection systems are included in section (3) of this rule; (D) Impact on Existing Wastewater Facilities. Evaluate the impact of the proposed project on downstream existing wastewater systems (including gravity sewers, alternative sewers, pumping stations, force mains, and treatment facilities); (E) Project Description. Provide a written description of the project; (F) Location Drawings. Provide drawings identifying the site of the project and anticipated location and alignment of proposed facilities; (G) Engineering Criteria. Include design criteria for the proposed project; (H) Site Information. Provide project site information, where applicable, including topography, soils, geologic conditions, depth to bedrock, groundwater level, distance to water supply structures, roads, residences, and other pertinent site information; (I) Alternative Selection. Discuss the reasons for selection of the proposed alternative, including any pumping station sites, feasibility, and how the project fits into a long term plan; and (J) For flood protection follow the provisions listed in 10 CSR 20-8.140(2)(B). (5) Facility Plan. Facility plans shall include the following, in addition to the information in section (4) of this rule: (A) Planning and Service Area. Include a description or drawings of the planning area, existing and potential future service areas, the site of the project, and anticipated location of the proposed facilities; (B) Population Projection and Planning Period. Base the present and predicted population on a twenty (20)-year planning period. Consider phased construction of wastewater facilities in rapid growth areas. Design sewers and other facilities with a design life in excess of twenty (20) years for the extended period; (C) Wastewater Treatment Facility Design Capacity. The wastewater treatment facility design capacity is the design average flow at the design average BOD5. Establish the anticipated design average and design peak flows and waste loads for the existing period in accordance with section (3) of this rule. Include the basis of the projection of initial and future flows and waste loads; (D) Initial Alternative Development. Discuss the process of selection of wastewater treatment alternatives for detailed evaluation. Include all wastewater management alternatives considered, including no action, and the basis for the engineering judgment for selection of the alternatives chosen for detailed evaluation; (E) Detailed Alternative Evaluation. Include the following for the alternatives to be evaluated in detail: 1. Collection system revisions. Evaluate the proposed revisions to the existing collection system including adequacy of portions not being changed by the project; 2. Wet weather flows. Provide facilities to transport and treat wet weather flows in a manner that complies with federal, state, and local regulations; 3. Evaluate the no-discharge option and include it as an alternative in the facility plan. Also refer to 10 CSR 20-6.010(4) (A)5; 4. Evaluate the regionalization option and include it as an alternative in the facility plan; 5. Include the information outlined in 10 CSR 20-8.200(2) when the project includes wastewater irrigation or subsurface soil dispersal; 6. Site Evaluation. Consider the following criteria during site evaluation. Take appropriate measures to minimize adverse impacts when a site is critical with respect to the following items: A. Consider compatibility of the treatment process with the present and planned future land use, including noise, potential odors, air quality, and anticipated solids processing and disposal techniques. Wastewater treatment facilities should be separate from habitation or any area likely to be built up within a reasonable future period and shall be separated in accordance with state and local requirements. Refer to 10 CSR 20-8.140(2)(C) for minimum separation distances; B. Identify zoning and other land use restrictions; C. Evaluate the accessibility and topography of the site; D. Identify areas for future facility expansion; E. For flood protection, follow the provisions listed in 10 CSR 20-8.140(2)(B); F. Include geologic information, depth to bedrock, karst features, or other geologic considerations of significance to the project; G. A request for a geohydrologic evaluation conducted by the department’s Missouri Geological Survey is required in the following instances: (I) All new wastewater treatment facilities to identify stream determinations (gaining or losing); (II) All new outfalls or relocated outfalls; (III) All new or major modifications to earthen basin structures. Earthen basin structures shall not be located in areas receiving a severe collapse potential rating. Earthen basin structures located in areas receiving a severe overall geologic limitation rating are reviewed on a case-by-case basis. Earthen basin structures located in areas receiving a moderate collapse potential rating with an appropriate engineering solution are reviewed on a case-by-case basis; and (IV) All new features (e.g. wastewater irrigation sites, subsurface soil dispersal sites); H. Protection of groundwater including public and private wells shall be provided. When the proposed wastewater facilities will be near a water source or other drinking water facility, as determined by the Missouri Geological Survey or by the department’s Public Drinking Water Branch, include an evaluation addressing the allowable distance between these wastewater facilities and the water source. Refer to 10 CSR 208.140(2)(C); I. Determine the soil type and suitability for construction and depth to normal and seasonal high groundwater; J. Submit a soil morphology analysis conducted by a qualified soil scientist for all subsurface soil dispersal systems. Refer to section (7) of this rule; K. Identify the location, depth, and discharge point of any field tile or curtain drain in the immediate area of the proposed site; L. Include the present and known future effluent quality and monitoring requirements; M. Provide a discussion of receiving waterbody access for the outfall line; and N. Include a preliminary assessment of site availability; 7. Engineering criteria. Provide the engineering criteria and assumptions used in the design of the project. Provide the basis for unit operation and preliminary unit process sizing; 8. Location Drawings. Provide drawings identifying the site of the project and anticipated location and alignment of proposed facilities; 9. Flow diagram. Provide a preliminary flow diagram of treatment facility alternatives, including all recycle flows; 10. Removal efficiencies. Provide estimated loadings to and removal efficiencies through each unit operation in addition to total removal efficiency and effluent quality (both concentrations and mass); 11. Emergency operation. Provide a discussion of emergency operation measures as outlined in 10 CSR 20-8.140(7)(A); 12. New and innovative technology. See section (6) of this rule. Provide a contingency plan, in the event that such new technology fails to meet the expected performance; 13. Nutrient removal. Provide a discussion of nutrient removal capabilities, including the footprint available for expansion or treatment facility modifications necessary for nutrient removal for each alternative; 14. Solids. Include the solids handling and disposal alternatives considered and method selected consistant with the requirements of 10 CSR 20-8.170 and any conditions in the NPDES permit; 15. Treatment during construction. Develop a plan for the method and level of treatment (including solids processing, storage, and disposal) to be achieved during construction and include it in the facility plan. Refer to paragraph (9)(A)5. and subsection (10)(C) of this rule; 16. Cost estimates. Present cost estimates for capital construction cost, annual operation and maintenance cost (including basis), and a twenty (20)-year present worth cost for each alternative; 17. Environmental review. Include any additional environmental information meeting the criteria in 10 CSR 20-4.050, for projects receiving funding through the state grant and loan programs; and 18. Water quality reports. Submit all reviews, studies, or reports in accordance with 10 CSR 20-7, Water Quality; and (F) Final Project Selection. Present the selected project from the alternatives considered under paragraph (5)(E) of this rule, including the financing considerations and recommendations for implementation of the plan. Provide a project implementation schedule identifying project milestones. (6) New and Innovative Technology. (A) Evaluation of Technology Performance. To determine if new technologies of wastewater treatment processes and equipment or applications have a reasonable and substantial chance of success, the facility plan prepared for department approval shall include the following: 1. Monitoring observations, including test results and engineering evaluations demonstrating the efficiency of processes or equipment; 2. Detailed description of the sampling protocol and test methods that are sufficiently sensitive analytical methods for detecting, identifying, and measuring the concentrations of pollutants; 3. Testing, including appropriately-composited samples, under various ranges of strength and flow rates (including diurnal variations) and waste temperatures over a sufficient length of time to demonstrate expected performance under the range of climatic and other conditions that may be encountered in the area of the proposed installations. A control group may be necessary to demonstrate effectiveness; 4. Description of manufacturer’s warranty and performance warranty including all exclusions or limitations on the warranty, when available; 5. Complete design requirements, calculations, and all assumptions clearly documented and explained; 6. Documentation of how the new process or equipment functions; 7. A discussion of actual, full-scale operating experience or pilot test work. For full-scale operating experience, include the length of time that each installation has been in operation. For pilot test work, include a copy of the associated pilot test plan and final pilot test results report; 8. Discussion of known or anticipated start-up issues and operational issues that have occurred or may occur during the first year of operation; 9. A description of specific operator knowledge and skills needed to operate the proposed technology including an estimate of increased operator attention needed during start-up and the first year of operation; and 10. Other appropriate information. (B) Pilot Test or Demonstration Plan. Proposals for pilot tests and demonstration projects shall include the following in addition to the facility plan information in section (5) of this rule: 1. Goals, objectives, and benefits with an explanation as to why a pilot study or demonstration project is necessary to obtain additional engineering data; 2. Literature identifying key design parameters and related experience; 3. A description of the proposal with schematic diagrams, pictures, drawings, or any other important information; 4. Complete design requirements, calculations, and all assumptions clearly documented and explained; 5. Identification of associated environmental impacts, both direct and indirect; 6. Detailed description of the sampling protocol and test methods that are sufficiently sensitive analytical methods for detecting, identifying, and measuring the concentrations of pollutants; 7. Complete schedule for testing and evaluation including start, completion, and submittal of the pilot test or demonstration results report; and 8. Other appropriate information. (C) Evaluation of Collected Data. All raw testing data and the evaluation of the data and performance must be submitted for department review upon conclusion of the project demonstration. The evaluation shall identify and justify the removal of any excursions not representative of the new technology process or equipment from the data evaluation. (7) Soils Report. (A) Soils. Soil reports are required for all projects involving subsurface wastewater treatment and disposal. All soils investigations and resulting reports must be performed, signed, and dated by a qualified soil scientist as defined in section 701.040, RSMo. Soil observation pits (i.e., backhoe or hand dug) excavated to a depth to reveal the major soil horizons shall be utilized. (B) Soils Report. The soils report resulting from the investigation shall include the following information: 1. A copy of each soil profile description; 2. A description of all drainage features, rock outcrops, erosion, and other natural features that may influence the soil treatment area; 3. An evaluation of any identified limiting conditions or geologic risk factors affecting the soil’s ability to treat and disperse effluent, such as karst features, dense tills, clay pans, and fragipans; 4. Clear and legible scaled site plans, drawings, or maps identifying all applicable site features that could impact the soil treatment area(s). Previously prepared or otherwise available drawings or maps such as a survey prepared by a Missouri registered professional surveyor; an aerial photograph; a United States Geological Survey topographic map with the proposed soil treatment area clearly delineated; a United States Department of Agriculture Natural Resources Conservation Services county soil survey map with the proposed soil treatment area clearly delineated; or a digital orthophotograph prepared from a geographical information system may be used. The following shall be included on the drawings or maps: A. The location of all soil observation pits with the extent of different soils clearly delineated; B. Any existing or proposed dwellings and structures; C. Any site disturbances such as excavated or fill areas, existing roadways, and other hardscapes and proposed hardscapes, or related site disturbances; D. Location of all public and private wells, abandoned wells, or geothermal systems, and surface water features that could either influence or be impacted by the proposed soil treatment area. For minimum separation distances, follow the provisions listed in 10 CSR 20-8.140(2)(C); E. North orientation arrow; F. Identification of areas with conditions that would prohibit, limit, or adversely impact the siting of a soil treatment area including, but not limited to: sinkholes, wetland vegetation, bedrock outcrops, areas with a slope greater than fifteen percent (15%), and existing or abandoned field or drainage tiles; G. Identification of known existing, proposed, and observed easements and right-of-ways; and 5. A discussion of the findings and conclusions must include the following: A. Available area for the soil treatment area; B. Depth to limiting layers (e.g., water table, fragipan, bedrock) and the source of this information; C. Proposed application (loading) rates that take into consideration the drainage and permeability of the soils and the distance to the limiting layer. D. The source of the application rates for each soil horizon within the specific soil description; E. Frequency of flooding and ponding and the source of this information; F. Relevant characteristics (e.g., bedrock outcrops, sinkholes or karst features) on the proposed site or in the surrounding area that may indicate vulnerability for surface water and groundwater contamination and the source of this information; and G. Factors affecting the soils ability to treat and hydrologically control effluent and the source of this information. (C) Imported Soils. When a facility is importing soils for the subsurface soil dispersal systems, the following shall be specified: 1. Physical characteristics that are uniform in texture, structure, and pore space; 2. Transportation methods that ensures uniformity and consistency of the physical characteristics as close as possible to the original state upon delivery; 3. A sandy to loamy material, with less than ten percent (10%) clay and less than fifteen percent (15%) organic debris present; 4. Methods for removal of the organic layer; 5. No compaction of imported soil; 6. Placement in small “lift” increments of four to six inches (4"–6") instead of one (1) thick layer; and 7. Native soil is to be used for the vertical separation for the subsurface soil dispersal systems with the fill for the cap being imported soils. (8) Summary of Design. A summary of design shall accompany the plans and specifications and must include the following: (A) Flow and waste projections including design and peak hydraulic and organic loadings for sewers, pump stations, and wastewater treatment facilities; (B) Information to verify adequate downstream capacity of sewers, pump stations, and wastewater treatment and solids handling unit(s); (C) Type and size of individual process units including the following: unit dimensions; rates and velocities; detention times; concentrations; recycle; chemical additive control; physical control, flexibility, and flow metering; (D) Process diagrams, including flow diagrams with hydraulic capacity and organic waste load; (E) Expected removal rates and concentrations of permitted effluent parameters in the discharge from the wastewater treatment facility, including a separate tabulation for each unit to handle solid and liquid fractions; (F) Design calculations, tabulations, and assumptions clearly documented and explained from 10 CSR 20-8.120 through 10 CSR 20-8.210 used in the design of each unit process and the system(s) as a whole; (G) The appropriate pump curve with the system curve superimposed, as applicable; (H) Unusual specifications, construction materials, and construction methods; maps, photographs, diagrams; and other support data needed to describe the system; (I) Architectural, structural, and mechanical component design calculations as specified in 10 CSR 20-8.120 through 10 CSR 20-8.210; and (J) Anticipated effluent quality. (9) Plans. (A) General. 1. Plan components must include the following components on all plan sheets: A. A suitable title block showing the name of the project, owner, and continuing authority (refer to 10 CSR 20-6.010(2) and 20 CSR 2030-2.050); B. Scale ratios for mechanical drawings; C. Bar scales for aerial maps; D. A north arrow; E. Datum used; and F. Sheet numbers. 2. Plan format must include clear and legible plans drawn to a scale that allows necessary information to be seen plainly. Blueprints and hand-drafted plans are not acceptable. 3. Plan contents must include detailed plans consisting of the following: A. Plan views, elevations, sections, and supplementary views, which together with the specifications and general layouts, provide the working information for the contract and construction of the facilities; B. Dimensions and relative elevations of structures, the location and outline form of equipment, location and size of piping, water levels, and ground elevations; C. All known existing structures and utilities, both above and below ground, that might interfere with the proposed construction or require isolation setback, particularly water mains and water supply structures (e.g., wells, clear wells, basins), gas mains, storm drains, and telephone, cable, and power conduits. Show the location of all existing and proposed water supply structures located within five hundred feet (500') of the proposed or existing wastewater treatment facility; and D. Locations and logs of test borings, where applicable. Include test boring logs on the plans or in the specifications as an appendix. 4. Hydraulic profile for all wastewater treatment facilities must be included; and 5. Plan for operation during construction must specify the procedure for operation during construction that complies with the plan outlined in paragraph (5)(E)15. and subsection (10)(C) of this rule. (B) Plans of Sewers. 1. General plans. These plans shall show the following: A. Geographical features. (I) Topography and elevations. Clearly show existing or proposed streets and all streams or water surfaces. Include contour lines at suitable intervals; (II) Streams. Depict the direction of flow in all streams and high and low water elevations of all water surfaces; (III) Boundaries. Depict the boundary lines of the continuing authority and the area to be sewered; and B. Sewers. Show the location, size, and direction of flow of relevant existing and proposed sanitary and combined sewers draining to the treatment facility concerned. 2. Detail plans. Detail plans shall be submitted showing the following: A. Profiles having a horizontal scale of not more than one hundred feet (100') to the inch and a vertical scale of not more than ten feet (10') to the inch; B. Plan views drawn to a corresponding horizontal scale and shown on the same sheet; C. Location of streets and sewers; D. Line of ground surface; pipe size, material, and type; length between manholes; invert and surface elevation at each manhole; grade of sewer between each two (2) adjacent manholes; and any special construction features. Number all manholes on the plan and correspondingly number them on the profile; E. Elevation and location of the basement floor on the profile of the sewer where there is any question of the sewer being sufficiently deep to serve any residence; F. Locations of all special features, such as inverted siphons, concrete encasements, elevated sewers, etc.; and G. Detail drawings to show the following: (I) All stream crossings with elevations of the stream bed and ordinary high water mark, normal, and low water levels; (II) Details of all special sewer joints and cross-sections; and (III) Details of all sewer appurtenances such as manholes, inspection chambers, inverted siphons, regulators, tide gates, and elevated sewers. (C) Plans of Wastewater Pumping Stations. 1. Location plans. These plans must show the following: A. The location and extent of the tributary area; B. Any continuing authority boundaries with the tributary area; C. The location of the pumping station and force main; and D. Pertinent elevations. 2. Detail plans. Detail plans shall show the following, where applicable: A. Topography of the site; B. Existing pumping station; C. Proposed pumping station, including provisions for installation of future pumps; D. Maximum elevation of wastewater in the collection system upon occasion of power failure; E. Maximum hydraulic gradient in downstream gravity sewers when all installed pumps are in operation; F. Test boring and groundwater elevations; G. All pumping station appurtenances such as pumps, valves, level control switches, hatches, safety equipment, ventilation equipment, and hoisting equipment; and H. Flood protection map. For flood protection, follow the provisions listed in 10 CSR 20-8.140(2)(B). (D) Plans of Wastewater Treatment Facilities. 1. Location plans. Location plans shall include the following: A. The wastewater treatment facility in relation to the remainder of the system; and B. Sufficient topographic features to indicate its location with relation to streams and the point of discharge of treated effluent. 2. General layout. Layouts of the proposed wastewater treatment facility shall show— A. Topography of the site; B. Size and location of treatment facility structures; C. Schematic flow diagram(s) showing the flow through various units and showing utility systems serving the facility processes; D. Piping, including any arrangement for unit isolation (identify materials handled and direction of flow through pipes, including arrangements for independent operation); E. Hydraulic profiles showing the flow of wastewater, supernatant liquor, recycle streams, and solids; and F. Test borings and groundwater elevations. 3. Detail plans. Detail plans shall show the following, where applicable: A. Location, dimensions, and elevations of all existing and proposed treatment facilities and solids handling facilities; B. Elevations of high and low water level of the body of water to which the facility effluent is to be discharged; C. Type, size, pertinent features, and operating capacity of all pumps, blowers, motors, and other mechanical devices; D. Minimum, design average, and peak hourly hydraulic flow in hydraulic profile with wastewater, supernatant liquor, and solids flow through the treatment facility; E. Existing and proposed solids storage volumes in plan and profile; F. Adequate description of any features not otherwise covered by the specifications or facility plan; and G. Flood protection map. For flood protection, follow the provisions listed in 10 CSR 20-8.140(2)(B). (10) Specifications. (A) Specifications shall accompany the plans. The initial page shall bear the owner and continuing authority name, and a contact person for each (including phone number and address). (B) The technical specifications accompanying construction drawings shall include the following, but not be limited to all construction information not shown on the drawings which is necessary to inform the builder, in detail, of the design requirements for the quality of materials, workmanship, and fabrication of the project: 1. The type, size, strength, operating characteristics, and rating of equipment; 2. Allowable infiltration; 3. The complete requirements for all mechanical and electrical equipment (including machinery, valves, piping, and jointing of pipe); 4. Electrical apparatus, wiring, instrumentation, and meters; 5. Laboratory fixtures and equipment; 6. Operating tools; 7. Construction materials; 8. Special filter materials (such as stone, sand, gravel, or slag); 9. Miscellaneous appurtenances; 10. Chemicals when used; 11. Instructions for testing materials and equipment as necessary to meet design standards; and 12. Performance tests for the completed facilities and component units. It is suggested that these performance tests be conducted at design load conditions wherever practical. (C) Operation During Construction. Specifications shall contain a program for keeping existing wastewater treatment facility units in operation during construction. Should it be necessary to take units out of operation, specifications shall include detailed construction requirements and schedules to maintain compliance with effluent limitations and the facility’s NPDES permit. See paragraphs (5)(E)15. and (9)(A)5. of this rule. (11) Revisions to Approved Plans or Specifications. (A) General. Any revisions of approved plans or specifications affecting capacity, flow, system layout, operation of units, or point of discharge shall be approved by the department in writing, before such changes are made. (B) Addendum. Addenda must conform to all requirements in this rule. (C) Change Order. The owner, continuing authority, and contractor must sign and date change orders. (D) As-Built Plans. As-built plans clearly showing the alterations must be submitted upon department request at the completion of the work. AUTHORITY: section 644.026, RSMo 2016.* Original rule filed Aug. 10, 1978, effective March 11, 1979. Amended: Filed Sept. 14, 2010, effective June 30, 2011. Amended: Filed June 15, 2018, effective Feb. 28, 2019. *Original authority: 644.026, RSMo 1972, amended 1973, 1987, 1993, 1995, 2000.