village of lanark waste water treatment plant-2009 1.0

VILLAGE of LANARK

Waste water Treatment Plant-2009 1.0 PROCESS DESCRIPTION The design flow of village sewage to the wastewater treatment plant (WWTP) is 460 cubic meters per day(winter), and 514 m3/d(summer)* based on an average day domestic sewage production of 350 liters per capita per day (L/c/d) and a 20 year equivalent design population of 1,312 persons.

Figure 1. The Village of Lanark. The Village of Lanark Water and Wastewater Environmental Study Report dated April 11, 2008 actually shows 360L/c/d plus 40L/c/d inflow and infiltration (I&I); however in the design phase, MOE Ottawa has agreed to a design flow of 350L/c/d with no I&I since the project is using a vacuum collection system for wastewater (see Minutes of Meeting with MOE attached as Reference - See Reference B) The WWTP will be located on a 95 acre (38.3 ha) site to the west of the village. The layout of the plant on the site is shown in Fig 2.

Figure 2. WWTP - site plan. 1.1 Septage* During warm weather the WWTP is designed to accept septage from Lanark Highlands and two neighbouring townships – approximately 9,300 residences. Considering pump outs every three years and using 3,800 L (1,000 US gal) tanks, 3100 pump outs carried out during seven months of warmer weather results in an additional design daily flow of 54 m3/day*, during the warmer months. The septage station, designed and built by NWC, is presented in Figure 3. 1.2 Winter Operation The schematic of the plant during the cold months is shown in Figure 5. The design flow of 460 cubic meters per day is pumped into a covered retention cell # 1, of 8,000 cubic meters. This anaerobic digester allows for 17 days of retention at design flow to facilitate the digestion of the solids in the sewage, denitrifies any nitrates in the raw sewage and reduces the BOD of the influent through anaerobic digestion. The natural heat of the sewage and the flow through conditions will prevent the primary cell from freezing.

Figure 3. Septage Station – by NWC

Figure 4. Winter Operation, AFC* - Snowfluent*. The sewage then flows to an equalization cell, #2, of 12,500 cubic meters which will biologically process and store the sewage as required during times when snow cannot be made. It allows for an additional 27 days of storage at design flow and will allow further settling of solids, reducing BOD and phosphorus. The design calls for the equalization cell to be full at the end of warm weather spraying at the end of October and empty at the end of snow making season. This allows for 1 1/2 months loading in the equalization cell at the spring transition time.

Figure 5. EVC* system - winter operation.

A computerized, SCADA control system (Appendix - APP) will monitor air temperature and wind speed and direction. When the conditions are right (temperature between -5C and -50C, for example) the pumps and compressors will be activated and wastewater pumped at pressures up to 500 psig. to three nozzles located on towers in an engineered snow deposit site. In addition, compressed atomizing air is mixed with the wastewater at each nozzle. The design flow rate to the nozzles is 50 cubic meters per hour (max)- 33 m3/hr-avg. At current loading these parameters will provide retention for up to 67 days. As the community grows, over the years, this retention will reduce to the numbers above detailed. In all cases the retention exceeds MOE requirements as stated in the 2008 Design Manual. Based on historical weather data, the design uses a utilization factor of 70% i.e. snowmaking is designed, based on use of 70% of the snowmaking hours available on average (5/10 years), in order to increase the probability to 9.2 years out of 10, and 70% in the 10th year, between the beginning mid November to the end of March. See Fig. 6.

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Northern Watertek Corporation 5

Figure 6. Model 2 of the EVC* Weather Models.

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Figure 7. Spray dimensions. The atomizing process results in the stripping of gases such as CO2, which causes the pH of the wastewater to increase 1 to 2 pH units. The H2S and NH3 are also removed in a similar manner. This is sufficient to render phosphorus insoluble caused by the ionized ammonia slowly converting to ammonia gas in the snow pack (Figure 8).

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NH3

NH4+

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Figure 8 Percentage of Nitrogen as a function of pH.

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The gas is released (volatilized) to the atmosphere at undetectable levels (Fig 8). In sun light the ammonia breaks down to hydrogen and nitrogen, normally found in the atmosphere. As well, when water freezes it is a pure water crystal and all impurities in suspension or solution within the droplet are forced to the outside of the crystal matrix. Carbonaceous material, algae et al. agglomerate to the precipitating inorganics like chlorides, sulphates and nitrates, all of whom precipitate as these compounds lose their heat of crystallization. Before the snow begins to melt, solids, rejected from the crystals have gravitated to the ground matrix.

Figure 9. Ablation curve.

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As the snow eventually melts (Fig. 9), the solids are left behind on the ground matrix. The melt waters seep into the soil strata, filtering any small particles not trapped on the soil surface, leaving these nutrients in the top 2-3 cm of the ground matrix for plants to uptake using phytoremedial forces and the consummation of nutrients, and contaminants by plant enzyme production. This final stage of the process involves vegetation which takes up the nutrients and a good deal of the water, which evapotranspirates into the atmosphere as pure water vapour. The phosphorus and nitrogen is utilized as needed fertilizer to the vegetation. The remaining effluent which then goes to groundwater is highly treated, free of the greater part of these constituents (see Table 4). TDS (Total Dissolved Solids) are removed through filtration effect of the melting snowpack, and the upper levels of the ground matrix. For the most part these nutrients/ inorganics will remain insoluble until regaining their heat of crystallization/formation. This does not occur until the “cold” melt water has exfiltrated into the ground matrix. Then these normally soluble salts will resolubalize for easy access by phytoremedial forces of the surface plant growth. See Fig. 10.

Figure 10. Dissolved solids removed through filtration effect. Further - the recent alarming growth of antibiotics, drugs, and birth control compounds in waste water are also removed, in a similar manner, something not accomplished by other systems. 1.3 Warm Weather Operation The schematic for the system during warm weather operation is shown in Fig. 11. The design flow of 460 cubic meters per day is mixed in the covered retention cell #1 with septage at a design flow of 54 cu meters per day, calculated over 7 months. The covered retention cell of 8,000 cubic meters allows for a minimum of 16 days of retention at design flow to facilitate the complete digestion of bio-

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solids in the sewage, denitrify any nitrates in the raw sewage and reduce the BOD5 of the influent through anaerobic digestion. See table no. 1

Figure 11. Summer operation.

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Droplet Diameter Figure 12. Percent efficiency of evaporation vs. droplet dia. and temperature (T.)

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Figure 13 Summer Spray.

The equalization cell #2, will be empty at the end of March, and will take approximately 1 1/2 months to fill. This accommodates the requirement for pretreatment of accumulating waste water for summer spraying.

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Table 1: RIF-40 SYSTEM* – NORTHERN WATERTEK CORP. LANARK EVC* SYSTEM – Summer operation ONLY – See Figure #13

It is established on the basis that the total load and concentration of constituents, of the septage is added gradually, over the whole day. It is logical to lower the initial effect of the

influent septage' concentrations to approximately1/4 of those indicated initially, for septage from the Design Manual.

N/D means non-detectable / measurements below MDL(min. detection Limit) IC- means increase in concentration by RIF aerobic filtering

DC- means decrease in concentration by biodegradation or dilution( volumetric ratio of cell sizes) ALL CONCENTRATIONS IN mg/l( milligrams per litre)

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Table 2: RIF Functions and Constituent

Thus, warm weather operations would commence while cell #2 is refilling when temperatures are above freezing. This allows for a total of over 40 days of storage at design flow. The design calls for the contents of the equalization cell to be circulated through a RIF (Recirculating Intermittent Filter - Figure 14), three times to ensure tertiary level treatment. This includes the daily inflow of raw sewage, and septage.

Figure 14 RIF Filters--Chester NS The RIF System takes its suction on cell # 2 and recycles the effluent 3 times, back to cell #1 to denitrify the cell #2 waste water as well as dilute the influent to cell # 1. Aeration is installed in cell # 2, to ensure effective nitrification. Tables 2 and 3, clearly show the effectiveness of the RIF Filters treatment on high BOD waste waters, re reduction of constituent contaminants.

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Table 3: RIF Functions and Metals constituent values

Again, the SCADA control system, (Appendix - APP), continuously monitors temperature, wind speed and direction and humidity. When atmospheric conditions are acceptable, effluent from the equalization cell is pumped to the nozzles at pressures up to 500 psig where it is atomized with compressed air to form very fine droplets. This allows controlled evaporation rates in the order of 50- 70% (Fig. 12) to be achieved reducing the hydraulic application (loading) to the ground matrix, accordingly.

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Table 4: Winter Process Values - Performance Summary Primary Municipal Sewage Treatment Followed by EVC* & Exfiltration

Parameter Influent Influent Lagoon Lagoon EVC* EVC* EVC*

Low High Low High Low High Exfiltration

BOD5 120 250 6 20+ 0 2 ND

SS 200 315 5 30 3 5 ND

PH 6.8 7.2 6.7 7.2 8 9 ND

Ammonia 7.5 40 7.5 40 0.1 0.1 ND

Organic N 1 10 1 10 0.2 0.2 ND

NO2 0.5 1 0.5 1 0.01 0.01 < 0.01

NO3 1 2 1 2 0.1 0.1 < 0.1

TP 5 15 1.5 6 0.01 0.1 ND

F-Coli Millions Milions Millions Millions < 4 < 4 ND Pathogens In Aerosol

NA NA NA NA ND ND NA

Coliphage In Aerosol

NA NA NA NA ND ND NA

Gases such as CO2, NH3, H2S are stripped, raising the pH in a manner similar to winter operations, concentrating the residual constituents in the balance of the water fraction. The phosphorus is rendered insoluble by conversion of ionized ammonia to ammonia gas (Fig 8), which is then volatilized. The flow to each of the three nozzles varies between 11 and 17 cubic meters per hour depending on the weather conditions. See Appendix - APP, which shows nozzle performance curves on the typical SCADA control screen design by NWC. The area receiving loading from the spray is approximately 15 to 20 ha. This design meets the spray irrigation standard of 55 m3 per ha per day. The 100 day limit on spraying is met, as well. With the implementation of the Westport system, in 1996, these Spray Irrigation parameters were considered in the Certificate of Approval application process. NOTE:

“Spray Irrigation” allows for secondary level waste water land application, at a rate of no more than 55 m3 per hectare per day for 100 days per year. This is normally an unmonitored system, other than for the volume and time limitations as stated above.

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The system proposed herein, operating both summer and winter is based on: a) detailed site hydrogeological analysis, b) very high treatment standards of the waste water, before land application, followed by c) detailed, regulated surface and ground water monitoring regimen. This regimen was determined appropriate for Westport and 13 years of monitoring without one non-compliance issue, has proven the original design and monitoring determinations to be totally justified. See Table 5. Table 5: EVC* vs. Spray Irrigation –based on data collected at Westport during 1998 Spray Irrigation Tests

Parameter Unit SPRAY EVC*

IRRIGATION

Average Average

Alkalinity mg/L 210 49

NH3 - N mg/L 6.45 < 0.5

BOD5 mg/L 51 < 1

Chlorides mg/L 47 < 10

Conductance umho 664 143

NO3 mg/L < 0.5 < 0.5

NO2 mg/L < 0.05 < 0.05

Organic N mg/L 6.4 < 1.0

PO4 as P mg/L 4.7 0.2

TP mg/L 5.1 0.21

E-coli

31,000 0

2.0 SYSTEM PERFORMANCE 2.1 Influent Characteristics Lanark Village is a rural community with a population of ,currently, 870 persons. There is no heavy industry and very few small businesses and so the waste water produced is and will be primarily residential quality. For the design, the following sewage and septage influent characteristics were used: See MOE Design Manual-Sec 19, Tables 19-1 and 19-2. As well, the Westport data, summarized in the attached 10-year study have been used when NWC experience differed somewhat with the concentrations listed in the MOE Design Manual.

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The design criteria of sewage is also based on the same source, as well as the Westport data. The MOE 2008 Design Manual, utilizes a BOD5 in the sewage of 200 mg/l and in the septage 6,500 mg/l resulting in a combined influent BOD5 of approximately 870 mg/l. This more than quadruples the concentration of the incoming sewage BOD5. The concentration effect on other constituents is similar. The successful implementation of the RIF system at Chester NS by NWC, processed influent far more concentrated than this (by a factor of 8-10 times) but similar to the concentrations of the incoming Septage. This system is ideal, during summer (non-freezing) months to reduce the waste water stream concentrations to better than tertiary standards. 2.2 Process Design Objectives For both summer and winter operations the design objectives for the effluent melting from the snow pack, and spray from cell #--2 for non-freezing seasons, are found in Table 6 (the demarcation line between EVC* performance and “Exfiltration” represents melt water application to the ground matrix). These objectives are supported by the data from the Westport 10 Year Study, REFERENCE “D”, and the Chester RIF performance data; see Tables 3 and 4. Table 6: Design Performance and OBJECTIVES for EVC*

Parameter Unit MDL UPGRADIENT UPGRADIENT MID SYSTEM DOWNGRADIENT

MW #1 MW #4 MW #2 MW #3

Average Average Average Average

TP mg/L 0.01 ND ND ND ND

PO4 as P mg/L 0.01 ND ND ND ND

Total NH3 mg/L 0.02 0.01 ND 0.01 0.02

Un-Ion. NH3 mg/L 0.02 ND ND ND ND

NO3 mg/L 0.1 ND 0.30 1.00 ND

NO2 mg/L 0.01 ND ND ND ND

pH - 1 8.09 7.87 7.75 7.82

Conductivity S/cm 1 429 659 914 797

2.3 Application Rate during Warm Weather Operation During non – freezing weather operations, the atomizing process at the nozzles results in droplet sizes of the order of 180-200 microns MVD (mean volume diameter). This will result in controllable evaporation rates of 50 -70% as can be seen in the graph at Fig. 12. Comparative Application Rates to Spray Irrigation Limitations-Fig. 6. Volume applied to Land —15ha—54,000m3 over 100 days At a minimum evaporation rate of 50%-(max. rate---70%).

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Daily Rates:

24 hrs---22.5 m3/hr 18 hrs---30 m3/hr 12 hrs---45 m3/hr 10.8 hrs @ Max flow rate—50m3/hr

2.4 Impacts- Land Application The performance of this WWTP is very site specific and, therefore, geotechnical studies play an important role in attaining that performance. As part of the ESR, Golder Associates Ltd. assessed the potential impact of the Membrane Bioreactor (MBR) plant on the 95 acre site to the west of the village. They used a design average flow of 524.8 m3/day to the shallow bury trench system, and nitrate and total phosphorus concentrations of 5 mg/L and 1 mg/L respectively in the effluent going to ground. The ESR concluded that, “with the combination of treatment and dilution by precipitation infiltration and surface runoff, the remaining nitrate and phosphorus concentrations in the treated effluent are not expected to result in unacceptable impacts to groundwater or surface water. Natural uptake by plants and microbiota in the wetland and pond may further reduce surface water concentrations.” It is to be noted that the application of effluent is continuous with this MBR System - daily, year round. The design application rate objectives for nitrates for the EVC* Plant are below that for the MBR Plant. Furthermore, while the influent design flows are the same, the effluent is being applied to the ground matrix at an application rate reduced by 50-60% because of evaporation from cell #2, process controlled evaporation from spraying both in summer and winter, sublimation losses during the winter, evaporation from melting snow surfaces in the spring and increased evapo-transpiration, since the effluent is only being applied during non-freezing weather, and under ideal conditions to ensure the evaporation rates are attained. The details of these calculations will be available in the final Certificate of Approval application. Therefore, based on winter considerations as well as non-freezing season’s performance, the system is able to provide suitable treatment and meet all environmental requirements on the proposed site. See “DESIGN OBJECTIVES” Table 6. 2.5 BUFFER AREAS Minimum distance from open cell # 2 to the nearest property line is 220 meters. Minimum distance from a tower to the nearest property line is 200 meters. The minimum distance from a tower to the nearest current residence is 380m.

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General buffer will be established in Fig. 2 is 100 meters inside the designated property lines.

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FFigure 15 Typical Main Control Center Layout.

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3.0 IMPACTS ON THE ENVIRONMENT 3.1 ODOURS This is a major concern of villagers since the WWTP is located to the west of the village. See Fig 1. Previous to the installation of the EVC* system at Westport there were many complaints regarding the odours from the old lagoon system. Since then, the complaints are virtually non-existent, because the cell levels are managed to minimize the odour-generating gases. The open cell # 2 at Lanark is, of course, designed to be facultative, with aeration to ensure adequate nitrification. See Fig. 16.

Figure 16: Aerated Retention Cell. System odours are generally only significant in the Spring when sunlight falls upon ice covering the lagoons, copious quantities of ammonia, H2S, are produced under the ice and normally released in significant concentrations, as the ice melts. The EVC* system has several design features that counter the creation of odours. -The primary cell #1, is covered and produces primarily Nitrogen, an odourless gas as a by-product of the denitrification process. -As odours are primarily a non–freezing seasonal characteristic, a RIF system is installed on the discharge of cell # 2 to lower constituent concentrations to better than tertiary standards. However, the RIF system, as well as the proposed aeration in cell # 2 are “AEROBIC” processes, which as nitrification processes, will control odours, in fact, virtually eliminating them –“WHEN THEY MOST NEED TO BE ELIMINATED”. Further; during spraying – summer or winter - the stripping of odoriferous gases is a continuous process. This is accomplished at levels that are undetectable. At

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the property limits, there would be absolutely no detectable odours. NWC will guarantee that, if the system is implemented and operated as instructed. Note: During winter, the equalization cell # 2, is also ice covered and odours from that source are virtually non-existent, This is when hydrogen sulphide and ammonia are normally formed in facultative lagoons and given off during ice out. The EVC* System ensures that the dropping water level results in a large air space over the residual liquid fraction providing adequate air contact that helps keep the contents aerobic thus preventing any build up of odours.( NH3, H2S etc.) 3.2 Bacteria Survival. The MOE Report – “Snowfluent* – The Storage and Renovation of Sewage Effluent by Conversion to Snow” (Appendix C) published in1985 concluded that after 2 to 3 weeks in the snowpack, the bacterial reduction rate was in excess of 99.9%, typical of chlorinated secondary effluent. Further, University of Ottawa studies showed that log 8 reductions(99,999999%) reduction of all bacterial activity was attained after 8 hours of exposure to temperatures below 0 Deg C. In addition the MOE study found that at 100m downwind bacteria concentrations were about one sixth of secondary waste treatment levels. Studies by AAFPRD(Agriculture Alberta) on high BOD waste water streams resulted in confirmation that downwind of spraying, conditions were identical as upwind of spray towers. 3.3 Aerosols. The 1985 MOE Report also found that during winter operations bacterial aerosolization levels at 100m downwind were about one sixth of levels found in secondary waste treatment aerated sections. Pathogen aerosolization at 100 m downwind was below the limit of detection… see: MOE 1985 Study-REFERENCE “C”. 3.4 Noise Noise levels are within the required levels by environmental standards. The MOE several years ago commissioned the “Hatch” study to examine the noise generated by snowmaking systems at Ski Resorts. It was found that there was no problem in meeting minimum standards of 45 Db at the outside wall of any building, used for accommodation, which is the Provincial Standard. The basis for sound attenuation is the relationship of the depletion of the sound energy as a function of the inverse of the square of the distance. Sound is very directional and the nozzles used in this application are pointed upwards. A discussion can be easily carried out beneath a tower without raising the sound level of the speaker.

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The sound is created, by the release of compressed air by the nozzle. The greater the compressed air volume released, at the same pressure the greater the noise created. Three years ago NWC produced a new nozzle that reduced the volume of air required by 2/3rds. This not only reduced the noise but also the energy consumption to produce that air, by 2/3rds. The noise levels produced at a tower, while somewhat variable can be measured reliably at 82 Decibels at 20 meters. Wind noise and minimal air movement( required by this process) is measured at 42 Db, just below the minimum standard for noise at the outside wall of a dwelling ---3 decibels is a full level of intensity difference---so the doubling of sound energy, say at 70 Db is 70Db+ 70Db = 73 Db. See Marks Mechanical Engineers Handbook- 8th Edition-Section12-pages 12-136-12 -143. In air the inverse proportional applies due to the wide area of propagation of the air waves and subsequent intensity depletion. Calculation of depletion of sound shows that for differences in sound greater than14 Db (Fig 1-page 12-137) that the upper sound level of 82 Db can be ignored as the sound measured at Westport was less than 45 Db at 250 meters from the point of generation. Special equipment was purchased to measure the sounds at a relative proximity to the towers, and then several hundred meters away, so that the inverse ratio could be established for the difference in sound energy levels. The results showed that at 250 meters distance, the air movement sounds were predominant and the nozzle sound were not perceptible. The greater the wind speed, the greater the air movement sounds. Sound generation from several towers is not indefinitely cumulative,* as depletion of sound energy begins at the source of generation—i.e. At each tower, It is cumulative within the immediate sound envelope. The 250 meters sound depletion distance, where the sound depletion range of each tower’s nozzle overlaps that of other towers, at most, this could only be an additional maximum of 6 Db. i.e. the addition of the same level of noise of 3 towers could only total 6Db. Not allowing for depletion of sound energy before “overlapping”. The depletion range for the sound impact on the public is, therefore, based on the last downwind tower. No complaints have ever been received at Westport, nor any other EVC* installation, re: noise from the towers. NWC will guarantee that no noise will be detected from such an operation. Dimensions from towers to property limits clearly demonstrate that any detectable sound impact will be below minimum ambient air movement required to operate the system.

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3.5 Impact of 70% Evaporation Rate on Ambient Air During warm weather operation a 70% evaporation rate at the nozzles would result in up to 848 m3 water per day, being injected into the atmosphere. A natural cone of dispersion would generate an air volume greater than 800,000 m3 by the time any moisture injected into the atmosphere reaches the first habitation in a prevailing wind situation—To wit:---550 meters to the nearest home just to the east and north of the site, from the nearest tower. The empty lot to the east of the site – the most northerly one is to be developed, eventually, by the owner. This, therefore, represents approximately 0.1% of the moisture already in the air at an average of 70% moisture content. Increases in Relative Humidity, therefore, would be immeasurable, and undetectable 4.0 MONITORING 4.1 Ground Water Ground water would be monitored using up to 4 monitoring wells, possibly, 2 up-gradient and 2 down-gradient. Down gradient measurements must be made clear of any impacts from the wetlands to the west and south of the land application area. Location of these wells will have MOE final approval. 4.2 Surface Water. Design of the site would be to control and prevent any direct surface water release off site. However, again, the “pond” location will assure that simply will not happen. It is possible that the infiltrated treated effluent could break out into the wetland and enter the pond. The waters would mix and then flow out as additional base flow for the receiving stream and Clyde River as identified in the Stantec ESR. 4.2 Topsoil Soil samples would be regularly taken and tested in a manner similar to Westport— every two years in the same location.

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REFERENCES—

A. Minutes of Meeting with MOE Ottawa—attached ** B. MOE Report ‘Snowfluent* – The Storage and Renovation of Sewage

Effluent by Conversion to Snow 1985 by Huber and Palmateer—MOE Files. C. NWC--- “10 Year Study of Westport** WWTP submitted to MOE, S. Mansoor Mahmood Phd.,P.Eng)” previously NOTE: The foregoing is a preliminary submission to MOE Approvals on behalf of the Village of Lanark to obtain the objective stated in the covering letter accompanying this document; Respectfully submitted, NORTHERN WATERTEK CORPORATION Original signed by J.A. White P.Eng. Jeffrey A. White P. Eng. President & CEO.

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Appendix – APP TYPICAL SCADA SYSTEM

Northern Watertek Corporation

As installed at Chester NS. The Lanark system will be very similar-

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Figure A1: Typical SCADA-1 main MCB schematic.

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Figure A2: Nozzle performance for winter months in SCADA-1.

Figure A3 SCADA-2 Summer operation curves.

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Figure A4 SCADA monitoring temperature, wind speed, direction and humidity.

village of lanark waste water treatment plant-2009 1.0

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