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... ."we F RATE LOADING STUDY FINDINGS STEWATER FLOW CALCULATIONS AND CHARACTERISTICS oaequately determine nitrogen loading from the Church, wastewater flows must be determined as accurately as possible. As with most Churches, Sunday is the heaviest wastewater flow day of the week, which influences flow estimates and design criteria. The following calculations illustrate flow projections: With the new building addition,there will be a c=acitof 210 Parishioners. According to Mr. Rodgers there is approximately 180 members of the Church, with an average Sunday attendance of approximately 150. Additional meetings include a small weekly meeting every Tuesday of 5 people and a monthly Council Meeting consisting of approximately 15 people (average people/wk). ac or, spe ' events such as bazbeques, car washes, etc. may the a 17 people per we k For example: 6 major events throughout the year with 150 - people at each ev = 6 events N50 people/event - 5weeks/yr= 17 people/wk. Therefore /J� the flow projections are as follows: ��s��orSS�'�'c'F r--(� �1�6 5 +4 people/wk x 5 gals/person=�fisU gals/wk=7 days/wk `IS&Zals/day=Average Daily Flow(ADF) It is our understanding that there is no kitchen for food preparation,thus reducing the organic loading that would normally be found in a Church kitchen having a garbage grinder or disposal. The characteristics of the wastewater flow will be predominately blackwater, with a comparatively small volume of sink water and no graywater from the washing of clothes, bathing, etc. B. CALCULATED IMPACT FROM NITRATE-NITROGEN LOADING From the anticipated wastewater characteristics described, the nitrogen originating from the Church may be at a higher concentration than what would normally be found in a typical domestic or household system. This can be attributed to the lack of a dilution effect which graywater would provide. In contrast, it can be theorized the nitrogen concentration may be less because anticipated toilet habits may differ from a residential setting. Data found in Table 4-16 of Small and Decentralized Wastewater Management Systems indicates the Total Kjeldahl Nitrogen(TKN)concentration in the effluent from a residential septic tank with an effluent filter vault ranges between 50 and 90 mg TKN/L. For conservative purposes, the highest value of 90 ppm TKN will be used in the following calculations. The TKN fraction is the total of the organic and ammonia-nitrogen fractions of nitrogen and it is conservatively assumed that this nitrogen concentration has the pential to all be oxidized, or converted to nitrate. The areal contribution of nitrate in terms of pounds per acre is as follows: 126 gals/day (ADF)x 3.79 L/gal =478 L/day x 90 mg N/L= 43 grams N/day x 365 days/yr T) 16 kg N/yr x 2.2 Ib/kg= 35 lbs N/yr_ 0.92 Ac= 37 lbs N/Ac/yr(Total areal contribution). Page-4- VaCley Ag Research