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HomeMy WebLinkAbout960200_Compliance_20210211ROY COOPER Governor MICHAEL S. REGAN Secretary S. DANIEL SMITH Director Thomas P. Uzzell Uzzell Swine Farm 404 Walnut Creek Road Goldsboro, NC 27534 Dear Mr. Uzzell: NORTH CAROLINA Environmental Quality February 11, 2021 Subject: Sludge Survey Testing Dates Certificate of Coverage No. AWS960200 Uzzell Swine Farm Animal Waste Management System Lenoir County The Division of Water Resources (Division) received your sludge survey information on February 9, 2021. With the survey results, you requested an extension of the sludge survey requirement for Lagoon 1 at the Uzzell Swine Farm facility. Due to the amount of treatment volume available, and the rate of sludge accumulation for the lagoon, the Division agrees that a sludge survey is not needed until December 31, 2024. The next sludge survey for Lagoon 1 at Uzzell Swine Farm should be performed before December 31, 2024. Please retain this letter and keep it with your farm records for reference. Please call me at 919-707-3663 if you have any questions. Sincerely, 3i,Uy A. -0l l Asap Bill Dunlap Animal Feeding Operations Program cc: Washington Regional Office, Water Quality Regional Operations Section Permit File AWS960200 DNorth Carolina Department of Environmental Quality Division of Water Resources E Q�� _ 512 North Salisbury Street 1 1636 Mail Service Center I Raleigh, North Carolina 27699-1636 NORTH CARD OapartmeM ofEnviw ronmenWl Uual� p ` 919.707.9000 Sludge Survey Evaluation Form Today's Date2/11/2021 Facility # 9600200 Owner: Thomas P. Uzzell Lagoon ID1 Sludge Survey Received:2/9/2021 Sludge Survey Performed:12/11/2020 Sludge Depth (Row O): (ft) 2.6 Existing Treatment Depth (Row P): (ft) 4.60 Start Date:01/01/91 Facility age at time of survey:(yr)30 Average Sludge Accumulation (ft/yr):0.09 3 Requested Extension: (yr) Requested Due Date2024 Sludge Accumulation during extension period: (ft)0.26 4.34 Treatment Depth Available after Extension: (ft) Sludge level OK?YES Ratio Estimates Based on DepthEXISTINGEXEMPTION Ratio of Sludge layer to total trmt depth 0.360.40 Ratio of Sludge depth OK?YES EXISTINGEXEMPTION Average Sludge layer thickness (T)2.62.86 Depth of the lagoon from top of bank to bottom soil surface (D) 10.110.1 Slope=Horizontal/vertical side slope (S) 33 Length at the top of inside bank (L) 375375 Width at the top inside slope (W) 175175 Thickness of existing liquid treatment zone (Y) 4.604.34 Lm Length at midpoint of sludge layer ()=L-2S(D-(T/2)) 322.20322.98 Wm Width at midpoint of sludge layer ()=W-2S(D-(T/2)) 122.20122.98 Vs Volume of sludge ()=Lm*Wm*T 102369.38113612.89 Vsg Volume in gallons ()=Vs*7.481 765825.36849824.40 Z Thickness of total treatment zone ()=T+Y 7.207.20 Lz Length at midpoint of total treatment zone ()=L-2(S)(D-(Z/2)) 336.00336.00 Wz Width at midpoint of total treatment zone ()=W-2(S)(D-(Z/2)) 136.00136.00 Vz Volume of total treatment zone ()=Lz*Wz*Z 329011.20329011.20 Ratio(R) of sludge layer volume to total trmt volume0.3110.345 Sludge Volume Ratio OK?YES Maximum extension until end of permit cycle Next survey to be done: (calendar yr) 12/31/2024 Notification letter mailed: 2/11/2021 Appendix 1. Lagoon Sludge Survey Form Revised August 2008 State University A&T State University A. Farm Permit or DWQ Identification Number 96-200 NCCOOPERATIVE B. Lagoon Identification Uzzell Swine C. Person(s) Taking Measurements D. Date of Measurement E. Methods/Devices Used for Measurement of: EXTENSION Eve Honeycutt Empowering People • Providing Solutions 12/11/2020 a. Distance from the lagoon liquid surface to the top of the sludge layer. sonar b. Distance from the lagoon liquid surface to the bottom (soil) of the lagoon. sonar c. Thickness of the sludge layer if making a direct measurement with "core sampler". sonar F. Lagoon Surface Area (using dimensions at inside top of bank): 1.67 (acres) (Draw a sketch of the lagoon on a separate sheet, list dimensions, and calculate surface area. The lagoon may have been built different than designed, so measurements should be made.) G. Estimate number of sampling points: a. Less than 1.33 acres: Use 8 points b. If more than 1.33 ac. acres x 6 = , with maximum of 24. (Using sketch and dimensions, develop a uniform grid that has the same number of intersections as the estimated number of sampling points needed. Number the intersection points on the lagoon grid so that data recorded at each can be easily matched.) H. Conduct sludge survey and record data on "Sludge Survey Data Sheet" (Appendix 2). Also, at the location of the pump intake, take measurements of distance from liquid surface to top of sludge layer and record it on the Data Sheet (last row); this must be at least 2.5 ft. when irrigating. I. At the time of the survey, also measure the distance from the Maximum Liquid Level to the Present Liquid Level (measure at the lagoon gauge pole): 0.8 J. Determine the distance from the top of bank to the Maximum Liquid Level 1.7 (use lagoon management plan or other lagoon records) K. Determine the distance from the Maximum Liquid to the Minimum Liquid level: 2.0 (use lagoon management plan or other lagoon records) L. Calculate the distance from the present liquid surface level to the Minimum Liquid Level 1.2 (Item K Minus Item I, assuming the present liquid level is below the Maximum Liquid Level) M. Record from the Sludge Survey Data Sheet the distance from the present liquid surface level to the lagoon bottom (average for all the measurement points) 8.4 N. Record from the Sludge Survey Data Sheet the distance from the present liquid surface level to the top of the sludge layer (average for all the measurement points): 5.8 O. Record from the Sludge Survey Data Sheet the average thickness of the sludge layer: 2.6 P. Calculate the thickness of the existing Liquid Treatment Zone (Item N minus Item L): 4.6 Q. If Item 0 is greater than Item P, proceed to the Worksheet for Sludge Volume and Treatment Volume. If Item 0 is equal to or less than Item P, you do not have to determine volumes. Completed by: Eve H. Honeycutt Date: 12/11/2020 Print Name /Signature Appendix 2. Sludge Survey Data Sheet* Revised August 2008 Lagoon Identification Completed by: Print Name Signature Date: 12/11/2020 (A) Grid Point No. (B) Distance from liquid surface to top of sludge ( C ) Distance from liquid surface to lagoon bottom (soil) (C)-(B) Thickness of sludge layer Ft. & in. Ft. (tenths) Ft. & in. Ft. (tenths) Ft. & in. Ft. (tenths) 1 0.0 0.0 0.0 2 0.0 0.0 0.0 3 0.0 0.0 0.0 4 0.0 0.0 0.0 5 0.0 0.0 0.0 6 0.0 0.0 0.0 7 0.0 0.0 0.0 8 0.0 0.0 0.0 9 0.0 0.0 0.0 10 0.0 0.0 0.0 11 0.0 0.0 0.0 12 0.0 0.0 0.0 13 0.0 0.0 0.0 14 0.0 0.0 0.0 15 0.0 0.0 0.0 16 0.0 0.0 0.0 17 0.0 0.0 0.0 18 0.0 0.0 0.0 19 0.0 0.0 0.0 20 0.0 0.0 0.0 21 0.0 0.0 0.0 22 0.0 0.0 0.0 23 0.0 0.0 0.0 24 0.0 0.0 0.0 Number of points with readings sonar X X sonar X X sonar Average of points x X 5.8 X X 8.4 X X 2.6 At pump intake 3.6 X X X X X X *AII Grid Points and corresponding sludge layer thicknesses must be shown on a sketch attached to this Sludge Survey Data Sheet. Appendix 3. Worksheet for sludge volume and treatment volume Revised August 2008 The average thickness of the sludge layer and the thickness of the existing liquid (sludge -free) treatment zone are determined from the information on the Lagoon Sludge Survey Form ( Items 0 and P, respectively). In this example, the average sludge layer thickness is 2.5 feet and the existing liquid treatment zone is 3.5 feet. If the lagoon has a designed sludge storage volume, see notes at end of the worksheet. The dimensions of the lagoon as measured and the side slope are needed for calculations of sludge volume and of total treatment volume. If the lagoon is a standard geometric shape, the sludge volume and the treatment volume in the lagoon can be estimated by using standard equations. For approximate volumes of rectangular lagoons with constant side slope, calculate length and width at the midpoint of the layer, and multiply by layer thickness to calculate layer volume, as shown in the example. For irregular shapes, convert the total surface area to a square or rectangular shape. For exact volumes for lagoons with constant side slope, the "Prismoidal Equations" may be used. Example Your Lagoon 1. Average sludge Layer Thickness (T) 2.5 ft. 2.6 ft. 2. Depth of the lagoon from top of bank to bottom soil surface (D) 11 ft. 10.9 ft. 3. Slope = Horizontal/ vertical side slope (S) 3 3.0 4. Length at the top of inside bank (L) 457 ft. 620.0 ft. 5. Width at top inside slope (W) 229 ft. 240.0 ft. 6. Length at midpoint of sludge layer Lm = L-2S(D-(T/2)) 398.5 ft. 562.4 ft. 7. Width at midpoint of sludge layer Wm= W-2S(D-(T/2)) 170.5 ft. 182.4 ft. 8. Volume of sludge (Vs) Vs=Lm Wm T 169,860 ft3 266,713 ft3 9. Volume in gallons: Vsg=V*7.5 gal./ft3. 1,273,950 gal. 2,000,344 gal. 10. Thickness of existing liquid tmt. zone (Y) 3.5 ft 4.6 ft 11. Thickness of total treatment zone (Z) Z= T+Y 6 ft 7.2 ft 12. Length at midpoint of total tmt. zone LZ = L-2(S)(D-(Z/2) 409 ft. 576.2 ft. 13. Width at midpoint of total tmt. Zone WZ = W-2(S)(D-(Z/2) 181 ft. 196.2 ft. 14. Volume of total treatment zone (Vz) Vz = LZ WZ Z 444,174 ft3 813,963 ft3 15. Ratio ( R ) of sludge layer volume to total Treatment Volume R = Vs/Vz 0.38 0.33 If the ratio R exceeds 0.50, than a sludge Plan of Action may be required. Check with DWQ for information on filing the Plan of Action. Note: If the lagoon has a designed sludge storage volume (DSSV), subtract that volume from both the volume of sludge (Vs) (Item 8) and from the volume of total treatment zone (Vz) (Item 14), and take the ratio. Then, R = (Vs-DSSV) / (Vz - DSSV) Example: If DSSV = 85,000 ft3, then R = (169,860 - 85,000) / (447,174 - 85,000) = 84,860 / 362,174 = 0.24. 16. Design sludge storage volume (DSSV) 85,000 17. Ratio (R) of sludge layer volume to treatment volume adjusted for designed sludge storage volume 0.24 0.33