Ground and Tropospheric Environmental Study of City of Wilson Educational Forest: An Environmental

Study

By: Austin Edmonds

Scholar’s Day April 15, 2015

Outline• Introduction

• Location and history of City of Wilson Educational Forest• Sample Collection

• Heavy Metal analysis, Phosphate analysis and Chemical Oxygen Demand (COD)• Sample Preparation

• Preparation for analysis of three tests completed• Analysis

• Instrumental: • ICP-OES (Heavy Metals)• UV/Vis (Phosphates)

• Titrimetric Method (COD)• Results• Conclusion• Future Work• Acknowledgements• References

Introduction• City of Wilson Educational Forest

• 657 Canal St E, Wilson, NC 27893 (Dendrology Drive)• 1.7 miles from Barton College• Total area: 75 acres• Small field area used to be a trailer park before Hurricane Floyd (1999)

Map of City of Wilson Educational Forest

Sample Collection• Heavy Metals

• Toxic amounts rarely natural in soil and water (Heavy Metal Soil Contamination, 2000)• Toxic to humans and animal and usually chronic conditions (exposure over a long period of time) occur (Heavy Metal Soil

Contamination, 2000)• Examples:

• Lead – mental lapse (Heavy Metal Soil Contamination, 2000)• Cadmium – affects kidney, liver, and GI tract (Heavy Metal Soil Contamination, 2000)• Arsenic – skin poisoning, affects kidneys and central nervous system (Heavy Metal Soil Contamination, 2000)

• Soil and water samples collected using 50mL centrifuge tubes• Areas tested:

• Water• A2SW• B2SW• E1CW

• Soil• A2• B2• C2• C3RB• D2• E2• F1• G1• G2• H1• H2 Pollution of the creek water (cups, pam can, bottles, etc.)

Sample Collection• Phosphates

• Lead to eutrophication in water, which leads to decreased dissolved oxygen levels (Phosphorus, 2012)

• Introduction to water predominantly occurs due to surface runoff (Phosphorus, 2012)

• Soil samples were taken using a corer and collecting in a 50mL centrifuge tube

• Areas of soil tested:• B3• C3• F1• G1• G2• H1• H2

Sample collection (forest area)

Sample Collection• Chemical Oxygen Demand

• Measures the amount of oxygen consumed by organic material in a water sample (Baird, C., Cann, M., 2008)

• The higher the organic material concentration, the less dissolved oxygen present in the water for living organisms

• 50mL centrifuge tubes were filled and capped underwater to allow no air to be in the sample collection

• Areas tested:• C2CW• C2SW• D2CW• C3CW

Flooded area of the forest (swamp water)

Sample Preparation• Heavy Metals

• Soil• Weigh 5 grams of sample • Add 2.5mL of 36% HNO3

• Add 10mL of DI water• Boil Gently for 5-10 min.• Decant/Filter• 3X washes of soil• Dilute to 100mL

• Water• Obtain 10mL aliquot of each water

sample into a clean beaker• Add 2.5mL of 36% HCL• Set on a hot plate for 5-10 min. to boil

gently• Pour into a 25mL volumetric flask• Dilute to volume using DI water• Take 10mL aliquot for analysis COD samples

• Phosphates• Soil

• Weigh 5 grams of sample • Add 20mL of DI water• Cap and shake well• Filter the mixture• Add 0.50mL of 36% H2SO4

• Dilute to 50mL mark

• COD• Pour sample in a beaker• Add 25mL of 18mol.

Sulfuric Acid• Add 50mL of Dichromate

Solution

Analysis of Heavy Metals• (ICP-OES)

• 10mL of prepared sample was taken and run through the ICP-OES

• Selected metals were analyzed

• Spike samples and check standards with concentrations of 1.50, 2.125, and 2.75 ppm were tested

Analysis of Phosphates• (UV-VIS)

• 1mL of prepared sample was taken

• 5mL of Ammonium Molybdate solution was added

• Diluted to 15mL with DI water• Absorbance was measured at

400nm• Standards were measured

with concentrations of 3.46, 6.92, 10.38, 17.30, and 27.68 mg/L

Analysis of Chemical Oxygen Demand• (Titration method)

• Prepared samples were placed on a hot plate for 1 hr. for digestion

• 3 aliquots of each sample were taken and put into Erlenmeyer flasks

• 5 drops of Ferroin Indicator were added to each• Ferris Ammonium Sulfate was used as the titrant• Color changes from green to red/brown at the end point• Volume of titrant was recorded and used to calculate the

COD• Dichromate solution was standardized by taking 25mL of

dichromate solution and 25mL of 18mol. sulfuric acid, then mixed and allowed to cool, followed by the addition of 5 drops of Ferroin indicator, then the solution was titrated with Ferris Ammonium Sulfate

• Two sets run:• COD1 (same day collection)• COD5 (five days after collection)

Results of Heavy Metals (Water)

EPA drinking water limits (Drinking Water Contaminants, 2014)

Heavy Metal(Water)

MCL/ppm

Aluminum 0.05 to 0.2Antimony 0.006Arsenic 0.010Bismuth NADCadmium 0.005Calcium NADCobalt NADChromium 0.1Copper 1.3Iron 0.3Lead 0.015Magnesium NADMercury 0.002Nickel NoneSelenium 0.05Thallium 0.002Zinc 5.0

Sample Al 396.152 As 189.042 Ca 396.847 Cd 214.438 Co 238.892 Cr 267.716

A2SW < 0.111567 < -0.036408 < 1.289 < -0.004314 < -0.015577 < -0.021420

B2SW 0.111366 0.032161 2.311 < -0.003144 < -0.010703 < -0.022796

E1CW 0.604785 < 0.011728 2.451 < -0.004225 < -0.009570 < -0.023740

Cu 324.754 Fe 259.941 Hg 184.950 Mg 279.553 Ni 221.648 Pb 220.353 Se 196.090

< 0.012659 < -0.017093 < 0.020792 < 0.549955 < 0.037162 < -0.084636 < -0.073426

0.051487 0.072345 0.031814 1.085 0.041685 < -0.027954 < -0.016398

0.014458 0.827452 0.03035 1.094 0.025415 < -0.050164 < -0.017185

Results of Heavy Metals (Soil) Heavy Metals(Soil)

Mg/kg or ppm

AluminumAntimonyArsenic 75BismuthCadmium 85CalciumCobaltChromium 3000Copper 4300IronLead 420MagnesiumMercury 840Nickel 75Selenium 100ThalliumZinc 7500

EPA Soil regulations (Heavy Metal Soil Contamination, 2000)

Sample Al 396.152 As 189.042 Ca 396.847 Cd 214.438 Co 238.892 Cr 267.716 Cu 324.754

A2 > 117.718 0.174818 > 17.023 0.036188 0.13325 0.138844 0.286226

B2 > 90.348 0.133116 > 16.624 0.023802 < -0.002272 0.110499 0.231424

C2 > 67.990 0.107157 > 16.575 0.025433 < 0.000544 0.11557 0.369993

D2 > 109.448 0.138228 > 17.598 0.020437 < -0.005213 0.114131 0.18221

E2 > 92.411 0.148297 > 16.546 0.027486 < -0.027320 0.138918 0.321049

C3RB 7.223 < 0.002918 > 15.849 < -0.000755 < -0.006979 < -0.011758 0.139749

Fe 259.941 Hg 184.950 Mg 279.553 Ni 221.648 Pb 220.353 Se 196.090 Zn 206.200

> 82.606 0.064904 7.297 1.199 0.865938 0.235405 0.886936

> 103.380 0.057782 > 18.152 1.187 0.536341 0.175791 0.785022

> 67.110 0.049697 11.689 1.403 1.735 0.114545 0.261494

> 58.768 0.056593 4.133 0.892235 0.54941 0.17453 1.853

> 91.072 0.055132 > 12.121 1.575 0.898345 0.173133 1.13

10.93 0.02338 1.464 0.154157 0.20682 < -0.044633 1.377

Results of Heavy Metals (Soil)Sample Al 396.152 As 189.042 Bi 223.061 Ca 396.847 Cd 214.438 Co 230.786 Cr 205.552 Cs 455.531 Cu 324.754 Fe 259.941

H2 > 33.922 < -0.119702 0.062866 > 14.869 < -0.035762 < -0.009404 < -0.030263 0.221668 < -0.017808 8.475

H1 > 30.400 < -0.110337 0.122347 > 15.143 < -0.035613 < -0.011218 < -0.005500 0.201234 0.036703 > 32.522

G2 > 33.138 < -0.110231 0.192186 > 26.495 < -0.035331 < -0.013234 < -0.006862 0.330112 0.105838 > 29.463

G1 > 37.722 < -0.118384 0.031581 > 16.763 < -0.032579 < -0.019898 < -0.035434 0.102691 < -0.049470 3.5

F1 > 52.932 < -0.093734 0.043894 6.877 < -0.034209 < -0.006742 < -0.020031 0.254476 < -0.037309 7.618

Hg 194.227 Mg 279.553 Ni 231.604 Pb 220.353 Sb 231.147 Se 196.090 Tl 276.787 Zn 206.200

0.033585 3.101 0.0854 0.244776 < 0.007962 0.087432 0.016572 0.663068

0.031572 1.642 0.046827 7.904 < 0.008077 0.095046 0.046939 0.663736

0.029666 5.053 0.47177 0.45215 < 0.006284 0.081889 0.043408 1.041

0.033855 2.137 0.064243 0.222915 < 0.001766 0.090336 0.010099 0.191597

0.043069 0.837214 0.089183 0.30121 < 0.013090 0.124525 0.019388 1.273

Results of Phosphate AnalysisZero Report Read Abs nm ________________________________________________ Zero (0.0898) 400.0

Calibration Collection time 3/18/2015 5:01:49 PM Standard Concentration F Mean SD %RSD Readings mg/L ______________________________________________________________________ Std 1 0.0580 0.0580 0.00 0.0581 0.0002 0.26 0.0583 Std 2 0.1254 0.1256 3.46 0.1255 0.0001 0.10 0.1256 Std 3 0.1963 0.1960 6.92 0.1958 0.0006 0.29 0.1952 Std 4 0.2613 0.2613 10.38 0.2613 0.0001 0.02 0.2614 Std 5 0.4034 0.4032 17.30 0.4032 0.0001 0.03 0.4031 Std 6 0.6054 0.6045 27.68 0.6050 0.0005 0.08 0.6049 Calibration eqn Abs = 0.01981*Conc +0.05783 Correlation Coefficient 0.99993 Calibration time 3/18/2015 5:04:48 PM

Calibration Readings

Analysis Collection time 3/18/2015 5:04:48 PM Sample Concentration F Mean SD %RSD Readings mg/L ______________________________________________________________________ B3 0.0844 0.0840 1.33 0.0842 0.0002 0.23 0.0841 C3 0.0936 0.0936 1.80 0.0936 0.0000 0.03 0.0935 F1 0.0962 0.0968 1.95 0.0964 0.0003 0.35 0.0962 G1 0.1821 0.1821 6.28 0.1822 0.0002 0.09 0.1824 G2 0.1722 0.1728 5.79 0.1726 0.0003 0.19 0.1726 H1 0.1264 0.1265 3.46 0.1264 0.0001 0.11 0.1262 H2 0.0832 0.0827 1.28 0.0831 0.0004 0.52 0.0835

Results of Chemical Oxygen Demand

Temperature(°C)

DO(mg/l)

Temperature(°C)

DO(mg/l)

0 14.60 23 8.56

1 14.19 24 8.40

2 13.81 25 8.24

3 13.44 26 8.09

4 13.09 27 7.95

5 12.75 28 7.81

6 12.43 29 7.67

7 12.12 30 7.54

8 11.83 31 7.41

9 11.55 32 7.28

10 11.27 33 7.16

11 11.01 34 7.16

12 10.76 35 6.93

13 10.52 36 6.82

14 10.29 37 6.71

15 10.07 38 6.61

16 9.85 39 6.51

17 9.65 40 6.41

18 9.45 41 6.41

19 9.26 42 6.22

20 9.07 43 6.13

21 8.90 44 6.04

22 8.72 45 5.95

Maximum dissolved oxygen concentration with temperature (Dissolved Oxygen and Biochemical Oxygen Demand, 2012)

COD1 COD5

Conclusions• Heavy Metals

• Water• Answer

• Soil• Answer

• Phosphates• Answer

• Chemical Oxygen Demand• COD1

• Answer• COD5

• Answer

Future Work• Air

• Smog

• Soil• Pesticides/Herbicides• Nitrates/Nitrites

• Water• Pesticides/Herbicides• Nitrates/Nitrites• Phosphates• Biological Oxygen Demand• Carbon Filtration

Acknowledgements• Dr. Dogbe• Dr. Carpenter• Mawuena (Dr. Dogbe’s son)• Barton College Science Department• City of Wilson

ReferencesBaird, C., & Cann, M. C. (2008). Environmental chemistry (4th ed., pp. 562-564). New York, NY: W.H. Freeman.

Brogan, J., Crowe, M., & Carty, G. (2001). Developing a National Phosphorus Balance for Agriculture in Ireland. Retrieved from https://www.epa.ie/pubs/reports/land/Developing%20National%20Phos%20Balance %20for%20Agriculture.pdf

Dissolved Oxygen and Biochemical Oxygen Demand. (2012, March 6). Retrieved from http://water.epa.gov/type/rsl/monitoring/vms52.cfm

Drinking Water Contaminants. (2014, October 29). Retrieved from http://water.epa.gov/drink/contaminants/#one

Heavy Metal Soil Contamination. (2000, September). Retrieved from http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_053279.pdf

Phosphorus. (2012, May 27). Retrieved from

http://www.epa.gov/agriculture/ag101/impactphosphorus.html