HomeMy WebLinkAbout400150_Sludge Survey (Reporting)_20230909Appendix I.Lagoon Sludge Survey Form Revised August 2008
A. Farm Permit or DWQ Identification Number
40-150
B. Lagoon Identification Sandy Ridge
C. Person(s) Taking Measurements Chuck Stokes
D. Date of Measurement 9/9/2023
E. MethodstDevices Used for Measurement of.
NCState LlnWrsity
A&T State Unnrersity
COMRATM
EXTENSION
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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.
talc
c. Thickness of the sludge layer if making a direct measurement with "core sampler".
talc
F. Lagoon Surface Area (using dimensions at Inside top of bank): 3.2 (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. 3 acres x 6 = 18 , with maximum of 24.
(Using sketch and dimensions, develop a uniform grid that has the same number of intersec tlons 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 2.6 fit. when Irrigating.
I. At the time of the survey, also measure the distance from the Maxamum Liquid Level to the Present Liquid
Level (measure at the lagoon gauge poley 1.2
J. Determine the distance from the top of bank to the Maximum Liquid Level 1.6
(use lagoon management plan or other lagoon records)
K Determine the distance from the Maximum Liquid to the Minimum Liquid level: 2.1
(use lagoon management plan or other lagoon records)
L. Calculate the distance from the present liquid surface level to the Minimum Liquid Level 0.9
(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) 8.5
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): 4.6
O. Record from the Sludge Survey Data Sheet the average thickness of the sludge layer. 3.9
P. Calculate the thickness of the existing Liquid Treatment Zone (Item N minus Item L): 3.7
Q. If Item O Is greater than Item P, proceed to the Worksheet for Sludge Volume and Treatment Volume.
If Item O Is equal to or less than Item P, you do not have to determine volumes.
Completed by: F q. q°"""a Date: 9/92023
Print Name /Signature
Appendix 2. Sludge Survey Data Sheet' Revised August 2008
Lagoon Identification Sandy Ridge
Completed by: Eve Honeycutt _fie rq. V,6,crtC Date: 9/9/2023
Print Name
Signature
(A)
( B )
( C )
( C ) - ( B )
Grid Point
Distance from liquid surface
Distance from liquid surface
Thickness of sludge layer
No.
to top of stud a
to lagoon bottom soil)
Ft. & in.
Ft. tenths
Ft. & in.
Ft (tenths)
Ft & in.
Ft. (tenths)
1
0.0
2
0.0
3
0.0
4
0.0
5
0.0
6
0.0
7
0.0
8
0.0
9
0.0
10
0.0
11
0.0
12
0.0
13
0.0
14
0.0
15
0.0
16
0.0
17
0.0
18
0.0
19
0.0
20
0.0
21
0.0
22
0.0
23
0.0
24
0.0
Number of olnts with readings
sonar
X X
sonar
X X
sonar
Average of X X
4.6
X X
8.5
X X
3.9
p,olnts
At pumpT
6.0
X X X X X X
intake
*All 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 O 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 m 2.5 ft. 3.9 ft.
2. Depth of the lagoon from top of bank to bottom soil surface (D) 11 fL 11.3 fL
3. Slope = Horizontal/ vertical side slope (S) 3 3.0
4. Length at the top of inside bank (L) 457 ft. 304.0 ft.
5. Width at top Inside slope (W) 229 ft. 600.0 ft
6. Length at midpoint of sludge layer Lm = L-2S(D-(T/2))
398.5
ft.
247.9
fL
7. Width at midpoint of sludge layer Wm= W-2S(D-(T/2))
170.5
fL
543.9
ft.
8. Volume of sludge (Vs) Vs=Lm Wm T
169,860
ft'
525,848
ft'
9. Volume In gallons: Vso=V'7.5 gal.e.
1,273,950 gal.
3,943,860
gal.
10. Thickness of existing liquid trot. zone (Y) .
3.5
ft
3.7
ft
11. Thickness of total treatment zone (Z) Z= T+Y
6
ft
7.6
ft
12. Length at midpoint of total trot. zone LZ= L-2(S)(D-(Z/2)
409
ft.
259.0
ft
13. Width at midpoint of total trot. Zone WZ = W-2(S)(D-(Z/2)
181
fL
555.0
ft.
14. Volume of total treatment zone (Vz) Vz = LZ W=Z
444,174
ft°
1,092,462
ft'
15. Ratio ( R ) of sludge layer volume to total Treatment Volume
R = Vs/Vz
0.38
0.48
tf 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)
Wimple: 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 0.48