NC0085359_Reactivation of Pretreatment Programs/ HWA Response_20231003

CALCULATIONS WORK SHEET
I. TWELVE MILE CREEK WWTP
Total Dry Tons = Annual Gallons x(% Solids_ 100)x 8.34 lbs./gallon
2,000 lbs./ton
= 9,500,000 x 0.035 x 8.34
2000
= 1,386 Dry tons per year
Rounded to 1,400 Dry tons per year
IL CROOKED CREEK WWTP
Total Dry Tons = Annual Gallons x(%Solids÷ 100)x 8.34 lbs./gallon
2,000 lbs./ton
= 1,500,000 x 0.035 x 8.34
2000
= 218 Dry tons per year
Rounded to 285 Dry tons per year
III. REPRESENTATIVE ANALYSIS OF TWELVE MILE CREEK WWTP AND
CROOKED CREEK WWTP WASTEWATER RESIDUAL SOLIDS
CONSTITUENTS: (next page-lab analysis in Appendix I)
RECEIVED
OCT 03 _J 3
NCIDEQ/ VPP/NPDES

UNION COUNTY
LAND APPLICATION PROGRAM
RESIDUALS ANALYSIS
Residual Type: Wastewater Treatment Plant
Date Sampled: July 20,2018
12 Mile Permit No. WQ0007486
Mineralization Rate 0.30 3.79 %Solids ND0089044
8.1 pH
Parameter % ." Mg/Kg Dry Weight" Pounds/Dry Ton
s.. ,. (%x 110,000) (Mg/Kg x.0.002)
Nitrogen(TKN) 6.370 63,700.000 127.400
Phosphorus 3.560 35,600.000 71.200
Potassium 0.603 6,030.000 12.060
IPAN(injected)* _ 4.293 42,930.000 85.860
PAN(surface)* 2.593 25,930.000 51.860
Ammonia Nitrogen 3.400 34,000.000 68.000
(Calcium 6.630 66,300.000 132.600
LCalcium Carbonate Eq. --- --- ---
Magnesium --- 4,880.000 9.760
Sodium --- 1,860.000 3.720
Sulfur --- 6,050.000 12.100
Nitrate N/Nitrite N --- 20.000 0.040
Barium --- _ --- --- SAR
Chloride --- --- --- 0.36
''Iron --- 5,390.000 _ 10.780 Ceiling Concen.
Aluminum --- 25,200.00 50.400 (Mg/Kg)
Arsenic --- 13.20 0.026 75
Cadmium --- 5.28 0.011 85
- -ro
Chromium --- 13.20 0.026 ---
Copper --- 213.00 0.426 4,300
Lead --- 13.20 0.026 840
Mercury --- 0.50 0.001 - 57
Molybdenum --- 13.20 0.026 75
Nickel --- 10.00 0.020 420
Selenium --- 13.20 0.026 100
Zinc --- 428.00 0.856 7,500 .
Rogers&Cal lcott# 8071344-02
*Determination of Plant Available Nitrogen(PAN):
Injected Application:
(Mineralization Rate)(TKN-Ammonia N) +Ammonia N +Nitrate N +Nitrite N =% PAN
Surface Application:
(Mineralization Rate)(TKN-Ammonia N)+(0.5)(Ammonia N)+Nitrate N +Nitrite N % PAN
Note: Constituents N.D. (Not Detected)or<detection limits arc listed as detection limits 1
for calculation purposes.

UNION COUNTY
LAND APPLICATION PROGRAM
RESIDUALS ANALYSIS
Residual Type: Wastewater Treatment Plant
Date Sampled: July 20,2018
Crooked Creek Permit No.WQ0007486
Mineralization Rate 0.30 3.57 %Solids ND0089044
6.6 pH
Parameter % Mg/Kg Dry Weight Pounds/Dry Ton'
(%x 10,000) (Mg/,Kg`x 0.002)
Nitrogen(TKN) 3.540 35,400.000 70.800
j Phos•horus 1.630 16,300.000 32.600
- Potassium 0.290 2 900.000 5.800
24.934
162.000 22.324
Ammonia Nitrogen 0.261 2,610.000 5.220
Calcium 2.030 20,300.000 40.600
Calcium Carbonate Eq. ---
Magnesium 610.000 5.220
Sodium t t►► 3.420
Sulfur ► 800.000 21.600
Nitrate N/Nitrite N ► ►►► 0.040
Barium --- SAR
Chloride - --- 0.57
Iron --- 15 900.000 31.800 Ceiling Concert.
Aluminum --- ►1 27.200 (Mg/Kg)
►► 0.028 75
0.011E 85
Chromium --- ► ► 0.081 ---
►► 0.556 4,300
Lead 28.20 0.056 840
Mercer ► 0.002 - 57
Mol bdenum 14.80 0.030 75
Nickel --- 30.00 0.060 420
Selenium --- 14.00 0.028 100
Zinc --- 483.00 0.966 _ 7,500
Rogers&Cal lcott N 807 1 3 44-0 1
*Determination of Plant Available Nitrogen(PAN):
Injected Application:
(Mineralization Rate)(TKN-Anunonia N)+Ammonia N+Nitrate N+Nitrite N-%PAN
Surface Application:
(Mineralization Rate)(TKN-Ammonia N) +(0.5)(Anunonia N)+Nitrate N+Nitrite N=%PAN
Note: Constituents N.D. (Not Detected)or<detection limits arc listed as detection limits
for calculation purposes.

IV. TOTAL PAN TO BE LAND APPLIED PER YEAR BASED UPON WEIGHTED
AVERAGE OF BOTH SOURCES:
Total dry tons of residual to be land applied per year: 1,685
Total PAN in lbs=(PAN in lbs/dt)x total tons of residual to be land applied
•
=46.86 x 1,685
=78,959 lbs of PAN per year
V. CROP INFORMATION ON NITROGEN UPTAKE PER YEAR
(See Management Plan)
VI. TOTAL ACRES NEEDED TO LAND APPLY THE POUNDS OF NITROGEN
CALCULATED ABOVE:
Total Acres Needed: = Total Pounds of Plant Available Nitrogen
Pounds of nitrogen needed for crop*
= 78,959
100*
Minimum acres needed based on most restrictive PAN = 789 Acres
*This value is based on 100 lbs/acre/year of PAN being applied to tall fescue pasture. The proposed
land application sites contain a mixture of tall fescue pasture and hay fields and coastal bermuda hay
fields included in this permit application. A request of 225 lbs/acre/year of PAN is being requested for
tall fescue hay. Additionally, a request of 400 lbs/acre/year of PAN is being requested for coastal
bermuda hay.

VII. SODIUM ADSORPTION RATIO (SAR)—TWELVE MILE CREEK WWTP
(This section is completed in mg/1) mg/kg have been converted to mg/1 by the following calculation:
mg/kg x% Solids(as a decimal)=mg/1
SAR=Na milliequivalent [0.5(Ca milliequivalent+Mg milliequivalent)]°'s
CONCENTRATION(mg/I) : Equivalent Weight = milliequivalents of Ion
CONCENTRATION(mg/1) EQUIVALENT WEIGHT MILLIEQUIVALENTS OF ION
SODIUM (Na)—70.494 23 3.065
CALCIUM (Ca)—2512.77 20 125.639
MAGNESIUM (Mg)— 184.952 12 15.413
SAR = 3.065_ [0.5(125.639+ 15.413)I°'s
SAR = 0.365
SODIUM ADSORPTION RATIO(SAR)—CROOKED CREEK WWTP
(This section is completed in mg/1) mg/kg have been converted to mg/1 by the following calculation:
mg/kg x% Solids(as a decimal)=mg/1
SAR=Na milliequivalent_ [0.5(Ca milliequivalent+Mg milliequivalent)rs
CONCENTRATION(mg/1) _ Equivalent Weight = milliequivalents of Ion
CONCENTRATION(mg/I) EQUIVALENT WEIGHT MILLIEQUIVALENTS OF ION
SODIUM(Na)—61.047 23 2.654
CALCIUM(Ca)—724.71 20 36.236
MAGNESIUM(Mg)—93.177 12 7.765
SAR = 2.654_ [0.5(36.236+7.765)j°'s
SAR = 0.566
1

VIII. DETERMINATION OF SITE LIFE FOR THE UNION COUNTY PUBLIC WORKS
LAND APPLICATION PROGRAM
The lifetime pollutant loadings shall not be exceeded. The site life is determined by calculating the
number of years that the site can receive the residual without exceeding the lifetime pollutant
loadings. The site life calculations will be based on the most restrictive crop plant available nitrogen
(PAN) requirement specified and the maximum dry tons of residuals to be land applied annually.
Therefore, in the table below the Tons of Residuals to be Applied/Acre/Year will be calculated as:
A. Crop with highest PAN requirement: Coastal bermudagrass hay
Associated PAN requirement: 400 lbs PAN/acre/year
B. Minimum acres needed based on maximum PAN applied per acre=
•
78.959 lbs PAN/year_400 lbs PAN/acre= 197 Acres
C. Dry tons of residual to be land applied per year: 1,685 dry tons/year
D. Tons of Residuals to be Applied/Acre/Year=dry tons/year land applied
minimum acres required
Tons of Residuals to be Applied/Acre/Year= 1,685= 8.55 tons
197
Tons of residuals to lbs/dry ton of each Projected lbs to be Allowable lifetime
Pollutant be applied per acre applied per acre per pollutant loadings Site life(years)
per year pollutant year (lbs/acres)
Arsenic 8,55 0.027 0.228 36 _ 158
Cadmium 8.55 0.0107 0.091 34 373
Copper 8.55 0.448 3.830 1,338 _ 349
Lead 8.55 0.031 0.269 267 992
Mercury 8.55 0.001 0.010 15 1559
Molybdenum* 8.55 -
Nickel 8.55 _ 0.027 0.229 374 1634
Selenium 8.55 0.027 0.228 _ 89 390
Zinc 8.55 0.875 7.478 2,498 334
THE LIMITING POLLUTANT IS: ARSENIC
THE SITE LIFE OF THE LIMITING POLLUTANT IS: 158 YEARS