Report - Nenthead

Oliver Ben Field130074056CEG3603 Research Methods in Environmental Pollution

Water analysis report on Nent River, to assess the impact on Nenthead Lead

and Zinc abandoned mine. Nenthead, Cumbria.

Author – Oliver Ben Field

Abstract:

It is widely known that water quality is greatly affected by close proximity mining activity. Investigation into the River Nent, Nenthead in an Area of Outstanding Natural Beauty and UK’s North Pennines Orefield covering an area of 25km2, Cumbria, on the Alston moor. They mined Lead (Pb) and Zinc (Zn) ore during the 17th and 19th century (Nuttall and Younger, 2015). During this study the Cation and Anion concentration that were collected along the River Nent were prepared in the laboratory and analysed further using Atomic Absorption Spectroscopy (AAS) for the Cations and Ion-Chromatography (IC) for the Anions. Results showed that certain ion were significantly higher leaving the mine compared to the concentration entering the mine site (Zn, Mg), others on the hand did not (Pb, PO4). The accuracy and precision of our results were fairly negligible apart from a few ions, such as Zn and Mg, however only a few results were under 10, thus predominately negligible and not recording the true concentrations in the sample. This study provides an insight to the effect that the abandoned mine had on the water quality of the River Nent, which could be related to sites of a similar nature.

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Student number - B3007405Table of Contents1:

Introduction.................................................................................................................................................51.1.1 – background information.....................................................................................................................61.2 – Study Location......................................................................................................................................61.3 – Aims and expected outcomes...............................................................................................................6

2.1- Methodology..........................................................................................................................................72.1.1– Step 1 – Select Equipment in field.....................................................................................................72.1.2 – Step 2 – Data collection.....................................................................................................................72.1.3 - Sample site locations:.........................................................................................................................72.1.4 - Site description:..................................................................................................................................82.2 - Analytic methods:..................................................................................................................................8

2.2.1 - Alkalinity:.......................................................................................................................................82.2.2 - Analysis of major and trace Cations and Anions:..........................................................................9

Storage:..........................................................................................................................................................92.2.3 – Anion analysis:..............................................................................................................................92.2.4 – Cation analysis:...........................................................................................................................12

Atomic absorption spectroscopy (AAS) was carried out for our further analysis. AAS measures the intensity of the light absorbed when photon move from ground state to excited state shown in figure 8.. 132.3 - Calculations of raw data:.....................................................................................................................15

3.1 – Cation and Anion results..................................................................................................................153.1.1 –Cation analysis..................................................................................................................................15Lower Limit of Detection (LLD):................................................................................................................15

3.1.2 - Sodium (Na):................................................................................................................................163.1.3 – Potassium (K):.............................................................................................................................173.1.4 - Calcium (Ca)................................................................................................................................173.1.6 – Lead (Pb).....................................................................................................................................193.1.7 – Zinc (Zn)......................................................................................................................................19

3.2.1 –Anions Analysis................................................................................................................................202.2.3 - Chloride (Cl)................................................................................................................................213.2.4 - Nitrate (NO3)...............................................................................................................................223.2.5 – Sulphate (SO4).............................................................................................................................233.2.7 – Phosphate (PO4).........................................................................................................................233.2.8 – Alkalinity (HCO3)........................................................................................................................24

3.3 – Charge balance calculations...............................................................................................................243.4 – Precision:............................................................................................................................................263.5 – Accuracy:............................................................................................................................................273.6 – other essential recordings...................................................................................................................283.5 – piper diagram......................................................................................................................................29

4.1 Discussion.............................................................................................................................................294.1 Overview:..............................................................................................................................................304.2. Macronutrients:.....................................................................................................................................30

Cations:....................................................................................................................................................30Sodium and Potassium:...........................................................................................................................30Magnesium and Calcium:........................................................................................................................30Anions:.....................................................................................................................................................31

4.3 - Micronutrients:....................................................................................................................................31Cations.....................................................................................................................................................31

4.5 - Charge balance:...................................................................................................................................324.6 -Accuracy and precision........................................................................................................................32

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4.7 - In field results:.....................................................................................................................................32

5 - Conclusion.............................................................................................................................................32

6 - Limitations............................................................................................................................................32

7 - Acknowledgements...............................................................................................................................33

8 - References.............................................................................................................................................33

9 – Appendices............................................................................................................................................38Appendix 1: Background information of the ore formation........................................................................38Appendix 2: affect of Pb on environmental and health risk........................................................................41Appendix 3: Heavy metal toxicity and effect on fish..................................................................................42Appendix 4: Colorometry and Autoanalyser further description................................................................43Appendix 5: holding times...........................................................................................................................44Appendix 6: A graph of our results with volume of acid on the x axis against the pH on the y axis.........45Appendix 7: calibration standards for Anions.............................................................................................46Appendix 8: calculations.............................................................................................................................47Appendix 9: Description on anions and Cations in waterways...................................................................48Appendix 10: Planks equation (AAS).........................................................................................................52Appendix 11: AAS advantages and disadvantages.....................................................................................53Appendix 12 – Reasons why used specific settings for Ion chromatography.............................................54Appendix 12 – Limestone formation - Nenthead........................................................................................55Appendix 14: calibration curves..................................................................................................................56

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Student number - B3007405

1: Introduction

The North Pennines is famous for veins of lead (Pb), Zinc (Zn) and fluoride (F) formed ~290 MA by hydrothermal process initiated by the Weardale granite (see appendix 1) (Global Geoparks Network, North Pennines, 2015). This lead to Pb and Zn mining in close proximity to the river Nent, which causes critical changes in the aquatic chemical composition, such as elevated toxic metals from weathering of exposed ores (Gajoweic and Witkowski, 2015).

High concentrations of toxic micronutrients have multiple affects on the aquatic systems J. A. B. Bass (2008) as part of the Environmental Agency concluded that toxic metals reduce species numbers of both macroinvertebrates and diatoms in the field, this can provide an effective and sensitive tool for detecting metal toxicity. The Toxicity Binding Model (TBM) provides clear toxicity thresholds of specific flora and fauna identified (see appendix 2 and 3).

The

river Nent occupies five mine water discharges shown in Figure 1. These are point sources of pollution, however river sediments, bank deposits and tailings material represent diffuse metal contamination occurring along the length of the river (Nuttall and Younger, 2015).

Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).Figure 1: Map of the Ninth Valley showing the main inputs of metal contamination (Nuttall and Younger, 2015).

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1.1.1: Background information

The underlying geology of the Nenthead catchment area is predominately limestone and till in with the lower catchment, whilst firestone sandstone and Stainmore formation (clay to gravel) occupy the upper catchment.

1.2: Study Location NY784434

Nenthead is located in an Area of Outstanding Natural Beauty for rare lichens and specific species of plant that grow on the metal-rich dumps, the valley being of a ‘National Ancient Monument’ (Nentheadmines.com, 2015). It lies 1,500 feet above sea level in close proximity to the river Nent (Cumbria RIGS, 1992).

1.3: Aims and expected outcomes

Aims:Analyse the River Nent anion and cation concentration from the base line flow of the river compared to the concentration leaving the mine.

Expected outcomes:Hoping to find multiple correlations because of the Pb and Zn mining activity via mine water discharge and an increase in toxic Anions and Cations leaving the mine in comparison to the base line flow.

2.1: Methodology

2.1.1: Select Equipment in field

Key:

Site 4

Site 3

Site 2

Site 1

Finish

Start

Figure 2: A map to show the underlying geology in the catchment area of the River Nent (Digimap.edina.ac.uk, 2016)

Site location

Stainmore formation

Till

Limestone

Firestone sandstone

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Site 1

Site 2

Site 3

Site 4

Student number - B3007405 0.45 micron filter Cation containers contained nitric acid to lower the pH Hatch alkalinity test kit Infield titration for alkalinity, adding sulphuric acid into the solution in situ with a bromocreasol

methyl red indicator Multiparameter water quality probe

2.1.2 – Step 2 – Data collection

We used judgemental sampling based on a professional knowledge on what sites would be best to sample for the greatest difference in ion concentration between sites. This discounts biased because we stated reasons why each site was chosen (section 2.1.3).

At every site location we had four pre-washed polypropylene bottles. Two for Anion collection and two for Cation collection contains nitric acid to lower the pH to prevents the Cations from precipitating out of solution. We filled the bottle to the rim, which prevents ions becoming volatile. Polypropylene bottles were used instead of glass containers because trace metals strongly absorbed onto the walls of the glass container as well as brittle and heavy (Corning, 2008). During collection we stud downstream of the collection site shown in figure 3 to prevent sample contamination. We then filtered them through a 0.45-micron filter to remove the particular matter.

To measure alkalinity we used a hatch alkalinity test kit with a bromocresol methyl red indicator mixed into the sample. Then titrated dilute hydrochloric acid into the solution until the colour turned grey, which meant the solutions pH was 4.5. We recorded the volume of hydrochloric acid titrated, the more alkaline the sample the more acid was used. We also recorded, Conductivity, Oxidation-reduction potential (EH), Total Dissolved Solids (TDS) and Temperature with Myron L Ultrameter II 6P, which was calibrated prior to each sampling event.

2.1.3 - Sample site locations:

2.1.4 - Site description:

Finish

Start

Figure 3: A map to show our sample locations along the river Nent (Cooke, 2015)

Key:

Sample point

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2.2 - Analytic methods:

2.2.1 - Alkalinity:Alkalinity was analysed within a week to maximise accuracy by ensuring analysis was well within the holding time of 14 days. Then standardised the hydrochloric (HCl) acid to an exact concentration to optimise accuracy and precision, the average concentration of HCl was 0.1028 m/L with a % Stdev of 2.9% after the four repeats. The acid was then diluted by a factor of 10 for precision and accuracy.

Lastly, we titrated 5ml of dilute acid at a time into the sample (25ml), whilst recording the pH until it reached 3, the results were plotted on a graph (see appendix 6).

2.2.2 - Analysis of major and trace Cations and Anions:

In the laboratory we multiplied our samples by 4 (figure 4) to allow an increased number of repeats, which improves reliability as anomalies done skew the data as significantly.

1B1

1B2

Figure 4: This shows how we split up our 4 samples at each of the 4 sites in the laboratory.

1B

1A2

1A11A

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Site number and grid reference

Site description

Site 1 (NY 780,435) This site is located approximately 10 meters (m) downstream of the last mining pollution discharge, allowing us to measure the anion and cation concentration of the waterway leaving the mining site.

Site 2 (NY 783, 433) The next site is upstream of site 1, and is also upstream of another discharge that is located between site 1 and 2, this gives us a better change of identifying the effect of the discharges.

Site 3 (NY 787,428) Located just before River Nent splits up into a number of tributaries, therefore we measured the water quality of the river before the tributaries entre the river, allowing us to analyse the effect of the tributaries on the Cations and Anions.

Site 4 (NY 789, 424) Lastly site 4 was the most upstream section of the Nent River, therefore we would be collecting samples from an unpolluted water that’s has been naturally filtered through the underlying geology.

Table 1: Site description of the location where we collected out 4 samples, in reference to figure 3.

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Student number - B3007405Storage:Samples were refrigerated at 4oC until we prepared or analysed the samples, maximum storage was up to 14 days for alkalinity and 6 months for the remaining metals.

2.2.3 – Anion analysis:

Holding time is the amount of time ions can be held in in solution under specific preservation conditions without affecting the accuracy of the analysis (Epa.gov, 2016)

We did the Anion analysis well within the holding time (6months) for the best chance of accurate results. The calibration standards were made from dry salts, into a 100ml volume with specific concentrations (mg L-1) of ion analysed (see appendix 7). We used these to calibrate the Equipment before each ion analysis.

Four accuracy check solutions (100ml) were made, two contained 10mg L-1 of the anions and the remaining two contained 5mg L-1. Three blank solutions were also made from deionized water to check ensure the Equipment wasn’t reading ions when there wasn’t any for accuracy (Intox.com, 2016). Finally, diluted sample by a factor of 5, to ensure the rods could absorb all the ions in solution, thus prevent supersaturating.

Ion Chromatography was our definitive analysis, which uses ion-exchange ions to separate molecular ions based on their interaction with the resins (Chemicool.com, 2016).

Equipment components (figure 5):1. Dionex ion-chromatography system (ICS-1000)2. AS40 autosampler, which is chemically inert and works with a variety of elements, it uses ion-

exchange resins to separate ions in aqueous solutions (Dionex, 2008).

3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.

Column type - IonPac As14A

Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).

Table 2 - Holding times of the Anions analysed (ALS Environmental, 2013).

Ion (anion) Holding timesCl- 6 monthsNO3- 6 monthsSO43

- 6 monthsPO44

3- 6 monthsHCO3

- 6 months

Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).Figure 5: Diagram of the Ion chromatography Equipment, with the solution getting pumped in and through the ion-exchange column and then through the conductivity detector (Bryn, 2015).

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4. The eluent (within the column): 8.0mM Na2CO3/1.0mM NaHCO3 solution,

5. Injection loop: 25ul (microliters)

6. Flow rate: 1ml/min. Increased flow rate results in easier distinction of which ion is getting absorbed at a given time (figure 6) (Srinivasan et al., 2010), (see appendix 13).

First we calibrated the equipment using the known standard solution, a chromatogram (a plot of the detector output vs. time), which converts each peak area to an ion concentration and produces results in a graph (thermo scientific, 2015). An R2 value is given to show the correlation, which ensures accurate results, an R2 value >9.4 the Equipment was calibrated (see appendix 14).

Each analysis took between 15-25 minutes, Na was analysed first because of contamination concert from sweat. We calibrated the Equipment before each ion analysis to ensure the Equipment’s accuracy via blank solution testing. Then we test the ion solutions to identify the peak of each ion and the time of absorption onto the positive exchange resins to attract negative ions (ammonium group) within the column (Jones, 2015).

Figure 6: the effect of flow rate on the overall run time was studied for a new IonPac AS22-Fast column at various flow rates shown above (Srinivasan et al., 2010).


































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The retention time is the time it takes for a solute to travel through the column, whilst the surface area represents the ion concentration (Chem.agilent.com, 2016). In figure 7 Sulphate has the highest volume and the longest retention time of 12.13 minutes. Nitrate has the lowest concentration with an 8.02 min retention time. Chloride has the fastest retention time (4.99 min) with a relatively small concentration, Phosphate was non identifiable. This plot was done for every sample.

2.2.4 Cation analysis:

Cations were prepared within 10 days for Atomic Absorption Spectroscopy (AAS) analysis, we also could have also Colorimetry and Autoanalyser (see appendix 4).

0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0-1.00

-0.50

-0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

4.50 Edmond 19.11.15 #26 1B1 ECD_1µS

min

1 - Chloride - 4.990

2 - Nitrate - 8.203

3 - Sulphate - 12.133

Figure 7: showing the retention times for Chloride, Nitrate and Sulphate, with the surface area of the peak representing for sample 1B1 the output.

Ion (Cation) Holding timeNa+ 6 monthsK+ 6 monthsCa2+ 6 monthsMg2+ 6 monthsPb2+ 6 monthsZn2+ 6 months

Table 4 - Holding time of the Cations analysed (ALS Environmental, 2013).

Standard 1B1 retention times (min)

Chloride (mins) 4.99Nitrate (mins) 8.02Sulphate (mins) 12.13Phosphate (mins)

N/A

Table 3 – Anion (1B1) retention times (min)


































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Two sets of calibration standards at a given concentration were made, one set for micronutrients (Zn and Pb) and the other for macronutrients (Na, K, Ca and Mg) (see appendix 7)

Four accuracy checks were prepared; two of the four contained 2.50 mg L-1 each of Na, K, Ca and Mg and 2000mg L-1 Cs (caesium) as an ionizing suppressant, which ensures balanced atoms through the release of electrons (Robinson, Skelly and Frame II, 2014). The other two contained 0.50mg L-1 of Pb and Zn with no Cs. Three blanks of deionized with 2000mg L-1 of Cs and another three without Cs were prepared.

Finally, diluted Na, K, Ca and Mg solutions ten times with 2000mg L-1 of Cs, whilst Pb nd Zn required no dilution. This was to ensure accurate and precise results.

AAS was carried out for our further analysis, it measures the intensity of the light absorbed when photon move from ground state to excited state shown in figure 8.

Flame used: acetylene

The atoms are absorbed by the wavelength emitted from the hollow cathode lamp, the monochromator isolates the wavelength chosen and photomultiplier quantifies the amount of light being absorbed by the atom cloud shown in figure 9. The reduction of light intensity is related to the number of absorbing atoms and this is proportional to their concentration in the sample (see appendix 1), (Jones, 2015).

Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.

Wavelength of each atom: K - 766.5 nm (Sisbl.uga.edu, 2016) Na – 589,590 nm - (physics rutgers, 2015) Ca - 422.7 nm Mg - 285.2 nm. (Chemistry 321L manual, 2015)

Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.Figure 8: Illustrating what the photon from the element being analysed does when it goes from a ground state to an excited atom, thus getting absorbed.

11


Appendix 11 lists positives and negatives

Figure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sampleFigure 9: Diagram of the Atomic Absorption Spectroscopy equipment, and the route of the sample

Interference considered

Description

Physical High viscosity reduces the speed of AAS< to avoid this we: Diluted the solution Used the same solvent for samples and standards Calibrated by standards (Jones, 2015).

Chemical Sample must be volatilised, three chemical interferences could have affected this: Formation of stable oxides, resulting in reduction of ground state atoms.

Therefore increase the heat of the flame. Ca absorbance reduced in presence of phosphate as forms calcium pyrophosphate

that is stable in acetylene flame. To prevent this you use a hotter flame. Ionization, therefore added an ionizing suppressant (Cs) (Jones, 2015).

Background absorbance

Occurs when absorbance bands coincide with atomic absorption wavelengths, it occurs at wavelengths <300nm. So we used HCL lamps that record the total absorbance of atoms and molecules, and we also used a D2 lamp only measures background absorbance (molecules). The computer subtracts the D2 lamp from the HCL to give us the atomic absorbance.

Table 7: physical, chemical and background absorbance interfaces compensated for

12


2.3 - Calculations of raw data:

3.1 – Cation and Anion results Appendix 9 for description the ions in aquatic systems

3.1.1 –Cation analysis

Lower Limit of Detection (LLD):

1. Dilution corrections - subtracted the average blank concentration from every sample (1A1 to 4B2) and multiplied it by 10 to improve accuracy.

2. Precision - calculated the average and standard deviation (Stdev) of each ion of each site. Then divided the Stdev by the average and multiplied this result by 100 to work out the precision (%RDS).

3. Accuracy – the accuracy check standards are subtracted from blank concentration averages, and then averaged. Then subtracted the volume of the accuracy check (i.e. Cations = 2.5(mg/L)) off the average accuracy check concentration and divided this by the volume of the accuracy check, and multiply by 100.

4. LLD – average and standard deviation of the blank and add them together and multiply the Stdev by 3. Lastly subtract the average blank concentration from the previous result and multiply it by the dilution of the ion (i.e. Na = 10)

5. Charge balance - divide the dilution correction by the atomic mass, and multiply it by the charge (i.e. Na+ = 1). Add up the total Cations and Anions through this equation: 100 × (total Cations – total Anions)/ (total Cations + total Anions) for each sample.

Cation Na K Ca Mg Pb Zn

Lower Limit of Detection (LLD) – mg L-1

0.0 0.17 0.62 0.17 0.08 0.02

Samples lower than LLD

N/a N/a N/a N/a 1B2 (-0.03)3A2 (0.03)3B2 (0.06)4A1 (-0.03)4A2 (-0.05)4B1(0.06)4B2 (0.03)

N/a

Table 8: Cation LLD, with named samples lower than the LLD of the specific ion

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3.1.2: Sodium

Figure 10 – shows the sodium (Na) concentration in relation to the position on the river, 1A1 – 1B2 is the first site, therefore water sample of River Nent as it leaves the mine. 4A1 - 4B2 is the last sample of the source of river Nent, therefore no pollution.


































Sample and site Na (mg L-1) K (mg L-1) Ca (mg L-1) Mg (mg L-1) Pb (mg L-1) Zn (mg L-1)

1A1 16.90 5.97 89.27 23.43 0.34 3.921A2 13.00 5.77 85.67 23.23 0.08 3.931B1 8.10 4.97 82.67 22.43 0.24 3.891B2 6.80 3.47 82.77 22.43 0.08 3.93

2A1 4.70 1.47 32.07 6.93 0.12 1.852A1 6.60 3.67 36.37 7.83 0.15 1.882B1 4.80 1.17 31.17 7.03 0.36 1.842B2 2.80 0.77 33.37 6.93 0.16 1.86

3A1 7.40 1.47 17.27 4.63 0.28 0.723A2 6.30 1.57 24.77 4.53 0.08 0.743B1 4.60 19.07 18.57 5.03 0.26 0.723B2 7.00 1.87 19.77 5.03 0.08 0.72

4A1 4.00 1.17 12.17 2.93 0.08 0.164A2 3.20 1.17 7.07 2.33 0.08 0.174B1 5.70 0.87 18.17 4B1 - 4.33 0.08 0.154B2 5.70 1.17 9.67 4B2 - 2.93 0.08 0.16

2.5mg L-1 major cations

accuracy check

Accuracy = 10.20

Accuracy = -15.93

Accuracy = 47.47

Accuracy = 16.13

Accuracy = 51.67

Accuracy = 45.33

0.5mg L-1 major cations

accuracy checkLLD

(detection limit)

0.00 0.17 0.62 0.17 0.08 0.02

Table 9: cation results

14


Na concentration has a higher concentration at site one (1A1 – 1B2), in comparison to site 4 (4A1 – 4B2), (figure 10). For example sample 1A1 has a concentration of 16.90 mg L-1, whilst sample 4A2 has a concentration of 3.20 mg L-1. The R2 value is 0.39, thus showing a weak correlation, however it still shows that there is a minor correlation suggesting that the Na concentration is slightly higher leaving the mine than it is entering.

3.1.3: Potassium

These results are relatively negligible, mainly because of the anomalous sample 3B1 (Fig 11), this causes the results of site 3 being misleading and negatively affecting the R2 of the graph. The R2 value is 0.034 showing no correlation from site 1 to 4, as a value of 0 represents no relationship. However if 3B1 was cancelled out it would show a better correlation, with the concentration being greater leaving the mine (5.97 mg L-1) than it is entering the mine (0.87 mg L-1).

3.1.4 - Calcium

Figure 11 – Showa the potassium (K) concentration in relation to the position on the river, 1A1 – 1B2 is the first site; therefore water sample of River Nent as it leaves the mine. 4A1 - 4B2 is the last sample of the source of river Nent, therefore no pollution.


































15


The first visual impression (Fig 12) is that there is a strong trend from low concentrations at site 1 to gradually increasing concentrations to site 4. The R2 value of 0.8, suggests an obvious correlation. The results also back this up, as the Ca concentration leaving the mine is 89.27 mg L -1 (1A1), whilst the value entering the mine is 7.07 mg L-1 (4A2) with intermediate value at site 2 at 36.37 mg L-1 (2A2).

3.1.5: Magnesium

Mg concentration clearly has a significant difference between site one and site 4. An R2 value of 0.74 signifies a clear correlation. The figures show that site 1(23.43 mg L -1) is substantially higher than site 4 (2.93 mg L-1). Therefore the Mg concentration entering the mine is considerably lower than the concentration leaving (Fig 14).

3.1.6 – Lead (Pb)

Figure 13 – Shows the Magnesium (Mg) concentration in relation to the position on the river, 1A1 – 1B2 is the first site; therefore water sample of River Nent as it leaves the mine. 4A1 - 4B2 is the last sample of the source of river Nent, therefore no pollution.


































16


Pb results are negligible and unreliable because of the lack of precision and accuracy, with a number of values are less than the blank concentration named above. These concentrations of Pb are in minor amounts because lead is a micronutrient, however there is no identifiable trend because of the huge range of results within each site (Fig 15). Therefore the results are fairly negligible, which is reiterated by an R 2

value of 0.19, suggesting no significant correlation.

3.1.7 – Zinc (Zn)

17


Zn results are very precise due to little fluctuation of results at each sample site (Fig 16). This chart also shows a clear trend between the Zn concentrations as we move up the River Nent. An R2 value of 0.90 showing a strong correlation, this shows that the Zn concentration is higher leaving the site (3.90 mg L-1) than the water entering the site (0.16 mg L-1). However, the high accuracy value suggests this may not be the true reflection of the site.

3.2.1 –Anions Analysis

Some of the values came out at the same concentration or lower than the blank, therefore it was unidentifiable 1A2 is seen to have a concentration of -1.95 mg L-1 of NO3 less than the blank concentration.

Anions Cl (2) NO3 SO4 PO4 HCO3Lower Limit of Detection (LLD) – mg L-1

4.6 10.13 0.00 0.00 0.00

Samples less than LLD

2A1 (2.83)2B1(3.05)3B2 (2.92)3B1 (3.64)4A2 (3.50)4B1 (2.77) and4B2 (2.89).

1A1 (-1.95)1A2 (-1.95)1B1 (2.01)1B2 (1.93)4A2 (-1.95)4B1 (0.28) and4B2 (-1.95).

N/A N/A ****

Table 10 - Anions LLD and the anion samples less than LLD

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Name Cl (mg L-1) NO3 (mg L-1) SO4 (mg L-1) PO4 (mg L-1)

HCO3 (alkalinity)

concentration (mg L-1)

1A1 5.59 10.13 123.02 0.00 1801A2 5.84 10.13 127.15 0.00 1881B1 5.48 10.13 128.00 0.00 1701B2 6.13 10.13 127.09 0.00 172

2A1 4.6 18.55 31.83 0.00 452A1 4.97 21.59 35.72 0.00 382B1 4.6 18.07 31.65 0.00 752B2 4.6 16.58 29.88 0.00 75

3A1 5.56 74.77 21.50 0.00 103A2 5.39 63.27 22.96 0.00 153B1 4.6 12.96 19.80 0.00 303B2 20.37 18.47 29.16 0.00 29

4A1 5.03 51.77 7.04 0.00 104A2 4.6 10.13 6.43 0.00 154B1 4.6 10.13 6.68 0.00 134B2 4.6 10.13 7.10 0.00 13

10mg/L anions accuracy

check

Accuracy = -27.93

Accuracy = -15.51

Accuracy = -7.91

Accuracy = -17.40


check5mg/L anions

accuracy check

Accuracy = -77.63

Accuracy = -30.38

Accuracy = -42.67

Accuracy = -100.00


checkLLD = 4.60 LLD = 10.13 LLD= 0.00 LLD = 0.00

Table 11: Completed Anion results

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2.2.3 - Chloride (Cl)

An R2 value of 0.00 shows no correlation between Cl concentrations from site 1 to 4, thus suggesting that the mining activity has no effect on the Cl concentration in the river. This is backed up through the concentrations at 1A1 is 5.59mg L-1 and 4A1 is 5.03mg L-1 this shows that there isn’t a significant difference in the Cl concentration in site 1 compared to site 4 (Fig 17). The anomalous result (3B2) with a concentration of 20.37 mg L-1 skewed the results at site 3, leading to heightened insignificance.

3.2.4 - Nitrate (NO3)

Figure 17 – Shows the second Chloride (Cl) lab analysis concentration in relation to the position on the river, 1A1 – 1B2 is the first site, therefore water sample of River Nent as it leaves the mine. 4A1 - 4B2 is the last sample of the source of river Nent, therefore no pollution.


































Figure 18 – Show the Nitrate (NO3) concentration in relation to the position on the river, 1A1 – 1B2 is the first site, therefore water sample of River Nent as it leaves the mine. 4A1 - 4B2 is the last sample of the source of river Nent, therefore no pollution.


































20


These results are somewhat negligible; the R2 value is 0.04, suggesting no correlation between the NO3 concentrations leaving and entering the mine. Site 3 has a large fluctuation as 3A1 has a concentration of 74.77 mg L-1 and sample 3B1 has concentration of 12.96 mg L-1, thus imprecise. Sample 4A1 is anomalous wit ha value of 51.77-mg L-1 compared to the next highest concentration of 0.28 mg L-1 (Fig 18). However, the data shows that the NO3 concentration at site 3 and 4 are higher than 1 and 2, so if anything the mining activity could act as an NO3 reducing agent.

3.2.5 – Sulphate (SO4)

The R2 value is 0.74 showing a relatively strong correlation between an increase in SO4 concentration as we move down the Nent River (Fig 19). The concentration increases 3 fold from site 4 to site 3 from around 7mg L-1 to around 21 mg L-1. The SO4 concentration increases hugely from site 3 to site 4 to a SO4 concentration more than 120 mg L-1, suggesting a significant difference in the SO4 concentration leaving the mine (126.32mg L-1) compared to the concentration entering the mine (6.81mg L-1).

3.2.7 – Phosphate (PO4)

Figure 20 – Shows the Phosphate (PO4) concentration in relation to the position on the river, 1A1 – 1B2 is the first site, therefore water sample of River Nent as it leaves the mine. 4A1 - 4B2 is the last sample of the source of river Nent, therefore no pollution.


































Figure 19- Shows the Sulphate (SO4) concentration in relation to the position on the river, 1A1 – 1B2 is the first site, therefore water sample of River Nent as it leaves the mine. 4A1 - 4B2 is the last sample of the source of river Nent, therefore no pollution.


































21

Student number - B3007405These results are negligible and the absence of concentration results in the inability to analyse PO4.

3.2.8 – Alkalinity (HCO3)

The R2 value 0.74 shows a relatively strong correlation, signifying an increase in the HCO3 concentration from site 4 to site 1. The average concentration at site 4 is 12.75mg L -1, this concentration increases 14 fold to reach the 177.5mg L-1 concentration at sight 1, showing a significant difference between the concentration entering the mine (site 1) in comparison to the concentration leaving the mine (site 4). In between sites 4 and 1 there is a gradual increase from site 4 to site 3 and another slight increase from site 3 to site 2.

Figure 21 – Shows the HCO3/ alkalinity change in relation to the position on the river, 1A1 – 1B2 is the first site, therefore water sample of River Nent are as it leaves the mining site. 4A1 - 4B2 is the last sample of the source of river Nent, where there has been no pollution and is predominately groundwater.


































22


3.3 – Charge balance calculations

The charge balance is the amount of positive and negative charges in solution (Ion.chem.usu.edu, 2015).

Overall the charge balance is positive apart from sites 3A1, 3B2 and 4A1 (Fig 22), these are only minor in compression to positive charges such as 44.86 mg L-1 at site 4B1. A value of zero means that the rivers

Figure 22: Shows the charge balance as you move up the Nent River, the furthest downstream point are samples 1A1 – 1B2 (site 1), the furthest upstream points are from 4A1 – 4B2 (site 4).


































Total Cations

Total Anions

Charge balance

7.39 5.64 11.777.02 5.87 7.306.57 5.64 6.476.48 5.67 5.50

2.47 1.78 16.232.90 1.86 21.942.43 2.27 3.522.43 2.20 5.02

1.63 1.97 -9.661.95 1.90 1.272.05 1.22 25.591.77 1.95 -4.82

1.06 1.29 -9.850.72 0.45 5.601.54 0.43 44.860.01 0.40 25.48

Table 12: Charge balance of the Anions and Cations of the river Nent.

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Student number - B3007405charge is in equilibrium with positive charges suggesting more Cations than Anions and negative value have more Anions. These results seem to be fairly negligible because of the lack of precision in site 2, 3 and 4, however site 1 is relatively consistent.

3.4 – Precision: Precision means results are in close proximity to each other, thus re-obtainable.

Na and K precision results are outside the 5% (%RDS) acceptable value, suggesting imprecise results that are not re-attainable, as they are not in close proximity to each other. However, K 2.5mg/L accuracy check has a value of 7.07%, thus close to 5%, suggesting fairly precise results but not at an acceptable value.

Ca 2.5mg/L accuracy check (1.92%) and site 1 (3.66%) are precise, thus re-attainable. Site 2 is also fairly precise (6.83%) but not acceptably so therefore not classified as re-attainable results. Site 3 (16.32%) and site 4 (40.35%) results are imprecise, thus not re producible.

Mg site 1 (2.30%) and 2.5mg/L accuracy check (0.97%) results are precise therefore re-attainable, however the rest of the results are outside the 5% value, thus imprecise and negligible, even though site 2’s value of 6.07% it’s not classified as precise.

Pb results are very imprecise and negligible, thus not consistent nor re-attainable. However, 0.5 mg L -1

accuracy checks have a value of 6.53%, but not of an acceptable value despite its low value.

Zn, 0.5 mg L-1 accuracy checks (21.41%) are imprecise, site 4 is only 0.21% off being classed as precise however by definition it is imprecise. Site 1 to 3 results are very precise as the highest value is 1.39% therefore reliable and precise.

Site number

Precision (%RDS) Na

Precision (%RDS) K

Precision (%RDS) Ca

Precision (%RDS) Mg

1 41.46 22.52 3.66 2.302 32.85 73.51 6.83 6.073 19.55 145.51 16.32 5.474 27 13.74 40.35 27.082.5 mg/L accuracy checks

18.22 7.07 1.92 0.97

Table 13: Cation macronutrient precision (%RDS) analysis.

Site number Precision (%RDS) Pb

Precision (%RDS) Zn

1 117.35 0.482 54.60 0.923 81.29 1.394 878.31 5.210.5 mg/L accuracy checks

6.53 21.41

Table 14: Cation micronutrients precision (%RDS) analysis.

Table 15: Anion precision (%RDS) analysis24


Cl and NO3 results are all out-side the acceptable value by a considerable margin, thus imprecise and un-attainable. However, site 1 is only 0.05% outside the acceptable level, thus showing relatively precise recordings. NO3 site 1 has a value of 21566.21%, thus entirely negligible.

SO4, site 1 (1.77%) and 4 (4.65%) are precise, thus re-attainable. However, the rest are imprecise and un-attainable. Site 2 (7.62%) is relatively precise but not of an acceptable value.

PO4, only the accuracy checks are available with a result of 116.25%, thus imprecise and negligible.

HCO3, site 1 has an acceptable precision of 5%, thus re-attainable. However, the rest of the results are imprecise and un-attainable.

3.5 – Accuracy:

Accuracy = results represent the true value of the solution (in our case), thus the % deviation of the known values

Table 16 shows that Na is only 0.2% off being an acceptable accuracy (10%), however the rest of the results are considerably above the acceptable level, thus suggesting negligible, inaccurate that don’t represent the true value of the ions in solution.

Precision (%RDS) SO4

Precision (%RDS) PO4

Precision (%RDS) HCO3

1.77 N/A 5

7.62 N/A 34

17.46 N/A 48

4.65 N/A 16

61.12 116.25 N/A

Accuracy (%) Na

Accuracy (%) K Accuracy (%) Ca

Accuracy (%) Mg

Accuracy (%) Pb

Accuracy (%) Zn

10.20 -15.93 47.47 16.13 51.67 45.33

Table 16: Cation accuracy analysis

Accuracy (%) Cl (2)

Accuracy (%) NO3

Accuracy (%) SO4

Accuracy (%) PO4

Accuracy (%) HCO3

5 mg/L -32.33 -15.51 -7.91 -17.40 N/A10mg/L -79.01 -30.38 -42.67 -100.00 N/A

Table 17: Anion accuracy analysis

25


All the results in table 17 are above the acceptable value (10%) apart from 1 SO4 value for 5mg/L at -7.91%, suggesting acceptable accuracy. The rest of the results are negligible and inaccurate, thus not representing the true ion concentration in solution e.g. PO4 10mg/L is -100.00%, and NO3 5mg/L is least inaccurate value (-15.51%).

3.6 – other essential recordings

The results taken in the field are incomplete with about half the data missing (table 18), thus somewhat negligible. However, you can see some trends such as a slight increase in temperature from site 4 (8.360C) to site 1 (8.89oC), also pH declines from pH 8 at site 2 to 7.73 at site 1. Clear correlations of TDS starting at 38 mg L-1 (site 4) and increases to 368 mg L-1 (site 1), conductivity has a similar pattern to TDS, the starting value of 57 (uS/cm) (site 4) and leads to 533 (site 1). Oxidation-reduction potential (EH (mV)) also has a slight increase from 91 at site 1 to 137.5 at site 4. Alkalinity (mg L -1 of CaCO3) also increases from 14.2 (site 4) to 118.3 (site 1).

3.5 – piper diagram

Name Location

Field Alkalinity (mg/L as CaCO3)

Conductivity (uS/cm) PH EH

(mV)TDS (mg/l)

Temp (C)

1A1 NY780435 98 532 7.69 140 368 8.891A2 NY780435 133 534 7.77 135 368 8.771B1 NY780435 1241B2 NY780435

2A1 NY783433 191 8.04 136 125 9.022A1 NY783433 191 7.99 133 126 8.642B1 NY783433 191 7.97 128 126 8.532B2 NY783433

3A1 NY7874283A2 NY7874283B1 NY7874283B2 NY787428

4A1 NY789424 21 57 7.82 91 38 8.364A2 NY789424 134B1 NY789424 124B2 NY789424 12

13

Table 18: results taken in the field

26


In the piper diagram (figure 23) sample 1 and 2 have a higher amount of Mg and Ca, whilst site 3 and 4 have high concentration of Mg and Ca with a substantial amount of Na and K (Survey, 2016).

4.1 Discussion

4.1 Overview: Warmer temperatures, higher oxygen availability and more acidic conditions promote the dissociation of ions. Oxygen react with ions to create energy, leading to increased kinetic energy, thus increasing the chance of particles colliding leading to chemical reactions (WhatReactions, 2016), the same occurs with increasing temperature. Acidic increases the dissociation of ions to maintain equilibrium, e.g. CaF2 as F-

ions reduce to form HF (White, 2016):

The complexity of the ions is an important factor, as the more complex chemical structure such as micro nutrients are less reactive, hence there low abundance dissolved. Macronutrients are in higher abundance due to less complex chemical structures, thus easily dissolved (WhatReactions, 2016).

4.2. Macronutrients: These are essential for growth, metabolism, and other body functions and are needed in large quantities (‘macro’ means large), (Sciencelearn Hub, 2016).

Cations:

Sodium and Potassium:The correlation for Na is strong because they are easily dissolved ions therefore the toxic minerals don’t have a great affect on their content throughout the River Nent. They get constantly absorbed by aquatic flora and fauna and dissolve when water runs through the geology and soil, which maintains equilibrium (Sciencelearn Hub, 2016). K would be similar if sample 3B1 was so anomalous, the assumption that this is human error as the rest of the results are fairly consistent.

Magnesium and Calcium:Ca and Mg ion dissolved from most soils and rocks, especially limestone, which is more prominent in the lower catchment (figure 2), the mining intensifies the limestones exposure, thus promoting disassociation of ions. Hence the sudden Ca and Mg increase at site 3 and 4 (Ngwa.org, 2016). Americas average Ca concentration is 21.8mg L-1, even in different continents the concentration are similar to site 2 (table 9), (Morr et al., 2006).

Anions:

Chloride and Nitrate: Cl blanks were of poor quality, resulting in results being below the lower limit of detection, with only one result being substantially above the LLD.

Decaying OM, sewage and nitrate fertilizers produces nitrate, these were minimal in the Nent catchment, causing low nitrate concentration. However, there were a few large concentrations at site 3, which could be caused by nitrate-contaminated tributaries that feed the river Nent (Ngwa.org, 2016).

Phosphate:

27

Student number - B3007405Results were non-existent because phosphate is often the limiting factor for growth of flora, therefore only containing minor amounts and the lack of Phosphorous fertilizers in the catchment. Therefore there is no PO4 source, also the IC my have struggled to absorb the ion (Bryn, 2016).

Sulphate:Sphalerite (ZnS) in the spoil heaps allows the S to become dissociated when weathered S gets oxidized to form SO4 (Sulphate) (Lenntech, 2015). The reason why there is more sulphate at site 1 than 2, 3 and 4 is because of the mine discharge 10 m upstream of site 1.

Alkalinity (HCO3) Increased HCO3 at site 1 and 2 compared to site 4 is because of the dissociation of CO3 from CaCO3 in limestone, which reacts with free H+ ions. This occurs further downstream because of the increased exposure and abundance of limestone.

4.3 - Micronutrients: They are essential to the human health in minor amounts, however if we have too much of these minerals then it can result in diseases such as lead poisoning (Mayoclinic.org, 2016).

CationsLead and Zinc: Pb results are negligible because the concentration is very small because Pb is fairly insoluble and AAS struggles to identify lead ions, hence Pb imprecise and inaccurate results (Bryn, 2016).

Zn has precise results because the AAS Equipment is very sensitive to Zn concentration, therefore able to detect minor concentrations accurately and precisely. Zn is moderately mobile and dissolves from Sphalerite therefore having higher concentrations at site Compared to site 4. The higher concentration means the AAS picks the ions up easier (Bryn, 2016).

4.4 - Charge balance: The total charge of this should be zero (Ion.chem.usu.edu, 2015), however our recordings are positive. These results are because of the misuse of equipment for Cations, resulting in inaccurate results (Nuttall and Younger, 2015). This is because when we measured the conductivity and ÷ 100 to give the total Cation and Anions in the field, it gave us poor charge balance when expressed as meq L-1. Resulting in the Cation concentration being too high (Nuttall and Younger, 2015).

4.5 -Accuracy and precision Both Anion and Cation results had varied accuracy and precision because of differential contamination between samples for precision and for varied accuracy because some accuracy check solutions were made well, but others were made poorly.

4.6 - In field results: Alkalinity is linked to the underlying geology and the high abundance of limestone, containing CaCO3

that acts as a buffer to the acidity. The pH decrease slightly at site 1 because of the increasing number of dissolved toxic ions, but the pH is still relatively high despite the toxicity of the ions.

Higher concentration of TDS at location, which in turn increase the conductivity of the water system at site 1 but is less at site 4 because of the reduced TDS. These tend to come from the clay bound geology (Till) (Environmental Measurement Systems, 2016). TDS has lead to the increase in EH, which has developed reducing conditions (Wiley.com, 2016).

5 - Conclusion There are more dissolved ions further down stream compared to the concentration at the source of the river because of increased exposure of rock because of the mining activity, as well as various discharges

28


from the mine. The analytic techniques were not as accurate or precise as we hoped because of the inaccurate accuracy check standards and possible contamination of samples (especially Na). However some concentrations saw good correlation as well as accuracy and precision, whilst others had negligible concentrations, precision and accuracy because insolubility of the ion and the inability for the analytic Equipment to identify the ions (PO4 and Pb). AAs and IC were quick, efficient machines that were easy to use despite their sophistication and for the most part produced significant trends and results. However, there were many results there were many insignificant and negligible results because of poor sample preparation for analysis.

6 - Limitations Could of used nitric oxide flame to improve Ca and Mg precision and accuracy. Increase the number of samples Make sure we record all data collected in the field Seasonal and diurnal variety throughout the year, therefore do repeats in different seasons and

times of day. Use better Equipment to analyse minor concentrations such as lead, which are also able to identify

the ion accurately and precisely. Buy in accuracy check standards rather than making them, they are accurate measurements that

would improve our results.

7 - Acknowledgements The author extends his appreciation to Bryn Jones and Martin Cooke for providing the appropriate Equipment and also organising the required transportation to the site, this allowed us to undertake our investigation safely, accurately and within the allotted time. Further appreciation goes out to my course members for their fieldwork cooperation, organisation and assistance throughout the study, which allowed us to collect the relevant sample. Also further gratitude goes out to Bryn Jones and Kath Rothwell for overseeing and helping with laboratory work and analysis.

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9 – Appendices

Appendix 1: Background information of the ore formation

Folding and faulting

Faults formed in the late carboniferous after the batholith, with a representation of its formation in figure 5 (Bulman, 2004). Earth movements bed rock to become gently folded and fractured forming the ‘Teesdale Dome’, developing wedge shape fractures. This caused lateral and vertical slippage forming faults that were later invaded by hydrothermal fluids, eventually depositing concentric layers of minerals.Figure 4 show that faults occurring in hard limestone and sandstone beds create clear, open fracture with a steep angled fault line (Bulman, 2004). Fault zones act as channels, concentrating migrating fluids in a prominent location, producing economic mineral deposits resulting from, mineral rich hydrothermal fluids and igneous intrusions (Holdsworth, 2001).

Formation of North Pennine mineral veins

Mineral deposits origin

Two formation types of mineralization occur at Nenthead: (1) Steeply dipping fracture-filling veins of hydrothermal origin. (2) Mineral flats. Doming during the Paleozoic created a dense network of fractures through the Alston Block, resulting in mineralizing hydrothermal fluids flowing into the fractures from the buried Weardale granite. Vertical mineralization occurs with greater abundance and concentration in more competent stratigraphic units (limestone’s and sandstones) because they create wide, open voids. In less competent rocks (shale’s), the ore bearing veins break up, creating gouge and dragged fragments of wall rock as well as breccia, forming small, low lying faults with poorly mineralized columns, shown in Figure 4 (Bulman, 2004). There are also mineral flats that occur in nine different limestone’s, however predominately occurring within the Great Limestone that occurs within the Alston Block. The flats are split into levels of Low, Medium and High flat horizons with the Great Limestone. High flats are the best developed because the metasomatic replacement of limestone by hydrothermal fluids, forming cavities that produce well-formed mineral specimens in Nenthead (The Rogerley mine, 2015).

Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).Figure 19: vein profile through strata of alternating hardness (Bulman, 2004).

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Mineralisation occurred 260-260MA (Permian), discovered by professor Cann at University of Leeds. Thus coinciding with the underlying granite. Figure 5 shows as fluids move away from the heat source (granite), there is a decrease in temperature that leads to various minerals coming out of solution depending on their chemistry and melting point, resulting in deposition on the walls of the fractures in concentric layers. 2 gangue mineral zones occur, known as the inner layer that hosts Fluorite Zone and the outer occupies Sulphide (Bulman, 2004).

Changing temperature and chemistry of mineralising fluids resulted in different minerals getting precipitated out at different locations in the veins forming concentric layers parallel to the wall rock, growing out into the voids. The temperature ranged from 200oC (closest to intrusion) to 60oC (furthest away). Early solutions were silica rich, thus depositing Quartz that hardened softer walls of which they were deposited on. Making the wall more docile to later vein solutions. Wide scale alternation of host rocks occurred in the early stage by iron and magnesium rich solutions, known as metasomatism, local hardening of rocks and partial re-crystallisation (Bulman, 2004). The mineral deposits bear a close relationship in terms of concentration and spatial variation with the focus of strain and faults with the greatest enlargement (Clarke, 2007). Primary minerals forming at higher temperatures are pyrite, quartz, pyrrhotite and chalcopyrite (copper sulphide); they are restricted to the copper subzone. The following phase started with Fluorite, then quartz, followed by and finally sphalerite. Baryte and witherite were deposited at lower temperatures therefore the last of the primary minerals to precipitate. Silver is associated with lead because the two elements have a similar atomic radius so they are both able to coexist in galena (on average 7 ounces of silver per ton of lead in Nent Valley).

Interesting feature of fluorite is its colour variety. The mineral creates shades of green, purple, amber and almost colourless with the same gross chemical composition. This proves a gradual change in chemistry and temperature during mineralisation (Bulman, 2004).

Secondary mineralisation

During secondary mineralisation the veins came in contact with slightly acidic ground water, rich in oxygen and carbon dioxide. When it came in contact with less stable minerals they were oxidised and secondary minerals formed. Oxidation produced metal oxides, hydroxides, sulphates and secondary carbonates from the primary sulphide and carbonate minerals. Limonite (hydrated iron oxide) was a key economical secondary mineral, developed from the breakdown of calcium iron magnesium carbonates, ankerite and siderite. Occurs with Ankerite and siderite rich flats exposed to the surface and iron carbonates are dissolved, leaving a rock rich in iron. Hemimorphite, hydrozincite and smithsonite are all secondary minerals, derived from sulphide and sphalerite (Bulman, 2004).

Alteration of Galena produces the lead carbonate, cerussite and anglesite (sulphate). Cerussite was found in abundance at Hughill Burn Mine in 1814 were a lead-bearing vein in the Great limestone had been altered. It was a very soft mineral that was easily extractable; no blasting was required and resulted in a rapid extraction (Bulman, 2004).

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Appendix 2: affect of Pb on environmental and health risk

Environmental and Health Risks by Lead: Exposure of Pb can cause many effects depending on level and duration of Pb. The developing foetus and infant are more sensitive than the adult. Mostly, the bulk of Pb is received from food; however, other sources may be more important like water in areas with Pb piping and plumb solvent water, air near point of source emissions, soil, dust and paint flakes in old houses or contaminated land. In air, the Pb levels are brought in food through deposition of dust and rain containing metal on crops and soil. Eight broad categories of Pb use are: batteries; petrol additives; rolled and extruded products; alloys; pigments and compounds; cable sheathing; shot; and ammunition. In environment, the Pb comes from both natural and anthropogenic sources. The Pb exposure can be through drinking water, food, air, soil and dust from old paint. The Pb is among the most recycled non-ferrous metals, so its secondary production has grown steadily. The high levels of Pb may result in toxic effects in humans, which in turn cause problems in the synthesis of haemoglobin (Hb), effects on kidneys, gastrointestinal tract (GIT), joints and reproductive system, and acute or chronic damage to nervous system (Govind and Madhuri, 2014)

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Appendix 3: Heavy metal toxicity and effect on fish

Fish diversity of any regime has great significance in assessment of that zone reference to environment and pollution, as well as it contributes to the necessary information for fisheries. Many fishes may be the bioindicators of environmental pollutants also15-16. Now, there is a great need to adopt rational methods and new technology in the fishing towards the conservation of fish diversity of several rivers. The management measures aimed at conserving freshwater fishes should be part of fishery policies. The broodstock maintenance centres and hatcheries should be established exclusively for endangered and critically endangered indigenous fishes for their in situ conservation16-17. However, in the conservation of fish diversity, it is essential to protect the fish from the environmental pollutants heavy metals, as these pollutants most often contaminate the fish. Various investigators in this regard have performed several studies. The heavy metals, e.g., As, Cd, Cu, Cr, Fe, Pb, Mn, Hg, Ni, Zn, tin (Sn), etc. are very important pollutants which cause severe toxicity to fishes. The studies performed in various fishes showed that heavy metals may alter the physiological and biochemical functions both in tissues and in blood Carpio. The As and inorganic As compounds, Cd compounds, Ni compounds, crystalline forms of silica, beryllium and its compounds have been said to be chemical carcinogens, resulting into the development of cancer in fishes. In a study on the spotted snakehead fish (Channa punctatus, Bloch), it was observed that when the high concentration (2 mM) of sodium arsenite (NaAsO) affected these fishes, they died within 2.5 hr. The chromosomal DNA of liver cells were fragmented which indicated that NaAsO might have caused death of those cells through apoptosis. The polluted marine organisms used as sea foods have caused health hazards, including neurological and reproductive disorders in both humans and animals. The chemicals of industrial effluents and products of ships and boats, such as heavy metals can cause toxicity in aquatic animals (Govind and Madhuri, 2014)

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Appendix 4: Colorometry and Autoanalyser further description

Colorimetry – this is a reagent that is added, which forms a coloured complex with the anion to be quantified. The absorption of the coloured complex with the anion to be quantified. The absorption of the coloured complex is measured with a UV-Ais spectrophotometer. LOOK UP – further information on these techniques

Auto-analyser – Often based on the same chemistry as previous manual techniques (e.g. colorimetric) auto-analysers make all necessary reagent additions and measurements automatically. LOOK UP – further information on these techniques

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Appendix 5: holding times Table 27: holding times of minerals

(ALS Environmental, 2013).

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Appendix 6: A graph of our results with volume of acid on the x axis against the pH on the y axis

Figure : Alkalinity graph through acidic titration

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Appendix 7: calibration standards for Anions

Table 21: calibration standardsStandard 1 Standard 2 Standard 3 Standard 4

Chloride (mg/L) 6.25 12.5 25.0 50.0Nitrate (mg/L) 3.13 6.25 12.5 25.0Sulphate (mg/L) 6.25 12.5 25.0 50.0Phosphate (mg/L) 3.13 6.25 12.5 25.0Table 5: calibration standard concentrations (mg L-1) for K, Na, Ca and Mg

Standard 1 Standard 2 Standard 3 Standard 4 Standard 5K 0.50 1.25 2.50 5.00 25.0Na 1.00 2.50 5.00 10.00 50.0Ca 5.00 12.50 25.00 50.00 250.0Mg 2.00 5.00 10.00 20.00 100.0

Table 6: calibration standard concentrations (mg L-1) for Pb and ZnStandard 1 Standard 2 Standard 3 Standard 4 Standard 5

Pb 0.13 0.25 0.50 1.00 5.00Zn 0.13 0.25 0.50 1.00 5.00

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Appendix 8: calculations

Calculations of raw data:

Dilution corrections – subtracted the average blank concentration from the original values and multiplied it by 10.

Precision - we worked out the average and standard deviation of each site. Lastly we divided the standard deviation by the average and multiplied this by 100 to work out the precision (%RDS). Precision means the results are re-obtainable when you go out into the field and re-collected data.

Accuracy – accuracy check standards subtracted from blank concentration averages, and averaged them. Finally subtracted the volume of the accuracy check (i.e. Cations = 2.5) off the average accuracy check concentration and divided this by the volume of the accuracy check, and multiply by 100.

LLD Detection limit calculation - standard deviation of the blank, then add the blanks average to the standard deviation and multiply the Stdev by 3. Lastly subtract this from the average blank concentration, and multiply this by the factor of dilution (i.e. Na = 10)

Charge balance - meq/L = divide the dilution correction by the atomic mass, and multiply it by the charge (i.e. Na+ = 1). Add up the total Cations and Anions, The equation: 100 × (total Cations – total Anions)/ (total Cations + total Anions) for each sample.

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Appendix 9: Description on Anions and Cations in waterways

Cations:

Sodium (Na) is weathered out from rocks and soil then transported to the aquatic systems. However, concentrations vary and tend to be much lower, depending on their geological conditions and wastewater contamination. Rivers contain approximately 9 ppm of Na, in a soluble form sodium always occurs as Na+. Sodium is present in the human body in amounts of about 100g,. However, an overdone can result in cardiac problems. (Lenntech.com, 2015)

Rivers generally contain 2-3 ppm of K, potassium in solution is mainly present K+ ions. K is dissolved via weathering processes in minerals such as feldspars, but is insignificant; chlorine minerals such as carnalite and sylvite are more favourable for K production. K plays an important role in bacteria, nervous systems and plant growth. K has a relatively high solubility therefore spreads quickly, and is seen to be a macronutrient/essential nutrient (non-toxic) (Lenntech.com, 2015).

Calcium naturally occurs in water due to its high abundance within the earths crust. Rivers generally have a concentration of 1-2 ppm, however in lime rich areas (i.e. limestone) the concentration can be as high as 100 ppm. Calcium carbonate has a solubility of 14 mg/L, which is multiplied by a factor of 5 with the presence of carbon dioxide. Calcium carbonate is the building stone for skeletons of marine organisms, and eye lenses. The calcium storage in plants is about 1% of dry matter. Ca causes water to be less toxic, affecting compounds such as copper, lead and zinc. Ca creates hard water, thus protects fishes from direct metal uptake as Ca competes for binding spots in the gills. (Lenntech.com, 2015)

Commonly a concentration of Mg in rivers is around 4 ppm. Mentioned above Mg is responsible for hard water, along with other alkali earth metals. Water with a high amount of alkali earth metals result in hard water, and water that lacks these ions result in soft water. Mg is more soluble with increased oxygen, and is often present as Mg2+ (aq) in water, but also as MgOH+ (aq) and Mg(OH)2 (aq). Magnesium hydroxide solubility is 12 mg/L, whilst magnesium carbonate is more soluble than this. Minerals such as dolomite and magnesite have high concentration of Mg, causing magnesium to be present in water as well as many anthropogenic affects such as chemical industries adding Mg to plastics. Mg is key for any organism but insect, it’s a central atom for the chlorophyll molecule, and is therefore essential for photosynthesis. (Lenntech.com, 2015)

Lead is a Non-essential element, organisms don’t need lead in large quantities, but can tolerate into certain level, if this threshold is exceeds then we start to suffer from various diseases, such as skin pigmentation and paralysis, it also reduces our mental capacity, because lead is poisonous to bodies. About 10-20 % of lead is absorbed by the intestines, women are generally more susceptible to lead poisoning than men. This causes menstrual disorder, infertility and spontaneous abortion. The foetuses are more susceptible to lead poisoning than mothers and they generally protect the mother from lead poisoning. Children absorb more lead per unit body weight than adults (up to 40%), it can cause a lower IQ, behavioural changes and concentration disorder. Because it’s a macronutrient river contain between 2 and 300 ppb, and the World Health Organisation (WHO) stated a legal limit of 50 ppb for lead in 1995, which has decreased to 10 ppb in 2010. Lead is fairly insoluble and doesn’t dissolve in water under 20 oC and pressure (1 bar). However, lead (II) acetate is a soluble compound. Led often binds to sulphur in sulphide form, or to phosphor to phosphate form. These form of lead are incredibly insoluble and present as immobile compounds in the environment. Lead is often soluble in soft, slightly acidic water (Kelly, Pano and Hackley, 2016).

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Student number - B3007405In Rome lead was often released as a by-product of silver mining, the mining that occurs at Nenthead could have a substantial affect on the Pb concentration. Lead and its compounds are generally toxic pollutants, it limits plants photosynthesis, but plants can still take up high amounts of lead (500 ppm) (Lenntech.com, 2015)Lead in petrol not just the element that counts it’s the form i.e. tetraethyl lead is worst for humans. Most in Nenthead is inorganic, so it’s not as bad as other forms such as the forms put in petrol. – caren Hudson Edwards – Mark mcmin Lead is a trace metal, however is essential to flora and fauna in minor amounts, therefore it is a micronutrient

Zinc - Rivers contain between 5 and 10 ppb of zinc, the WHO stated a legal limit of 5 mg Zn2+/L. The solubility of Zn depends on the temperature and pH of the water. When pH is fairly neutral Zn is insoluble. Solubility increases with increased acidity. Above pH 11 the solubility also increases. Zinc dissolves in water as ZnOH+ (aq) or Zn2+ (aq). Zinc is present in water because of ores such as sphalerite and smithsonite. These compounds end up in water on locations where zinc ores are found. Industrial wastewaters also contain Zn from galvanic industries, battery production etc. Zinc is a dietary mineral for humans and animals, but phytotoxicity may be underestimated. Zinc is a trace element and plays a key role in enzymatic processes and DNA replication. Also the human hormone insulin contains zinc, and is important for sexual development. A minimum amount is 2-3g as this reduces deficiencies, if this isn’t obtained it can cause immune and enzyme systems to suffer. A zinc overdose however can cause nausea, vomiting, dizziness, colics, fevers and diarrhoea, these occur after a 4-8g intake. (Lenntech.com, 2015)

Anions:

Cl is a major inorganic anion in freshwater, it often originates from the dissociation of salts such as sodium chloride or calcium chloride. These and other chloride ions originate from natural minerals, saltwater intrusion into estuaries and industrial pollution. Anthropogenic factors can have a great influence on the Cl concentration such as salt on roads. 250 mg/L of chloride is seen to be a detectable salty taste. The recommended maximum level of (Ruf.rice.edu, 2015)

Chloride behaves as a conservative ion in most aqueous environments, meaning its movement is not retarded by the interaction of water with soils, sediments, and rocks. As such, it can be used as an indicator of other types of contamination. Anomalously high concentrations can act as an “advance warning” of the presence of other more toxic contaminants. Concentrations of Cl- in natural waters can range from less than 1 milligram per liter (mg/L) in rainfall and some freshwater aquifers to greater than 100,000 mg/L for very old groundwaters within deep intracratonic basins (Graf et al., 1966; Psenner, 1989).

Chloride is non-toxic to humans, although there is a secondary drinking water standard of 250 mg/L. It is, however, deleterious to some plants and aquatic biota. Chloride is also a very corrosive agent, and elevated levels pose a threat to infrastructure, such as road beds, bridges, and industrial pipes. (Kelly, Pano and Hackley, 2016)

Nitrogen is one of the most abundant elements. About 80 percent of the air we breath is nitrogen. It is found in the cells of all living things and is a major component of proteins. Inorganic nitrogen may exist in the free state as a gas N2, or as nitrate NO3-, nitrite NO2-, or ammonia NH3+. Organic nitrogen is found in proteins and is continually recycled by plants and animals. (State.ky.us, 2015)

Nitrates in excess can cause eutrophication in downstream coastal waters by stimulating excessive growth of algae and other aquatic plants (when nitrogen is the limiting factor for growth) and indirectly causing oxygen deficiency in the bottom waters and reduced biodiversity. High concentration of nitrates also

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represents a health risk in drinking water (the World Health Organization guideline for drinking water is less 10 mg NO3-N/L, which is the equivalent to approximately 50 mg NO3/L) (Eea.europa.eu, 2015)

Nitrites can produce a serious condition in fish called "brown blood disease." Nitrites also react directly with hemoglobin in human blood and other warm-blooded animals to produce methemoglobin. Methemoglobin destroys the ability of red blood cells to transport oxygen. This condition is especially serious in babies under three months of age. It causes a condition known as methemoglobinemia or "blue baby" disease. Water with nitrite levels exceeding 1.0 mg/l should not be used for feeding babies. Nitrite/nitrogen levels below 90 mg/l and nitrate levels below 0.5 mg/l seem to have no effect on warm water fish. (State.ky.us, 2015)

Sulfates occur naturally in numerous minerals, including barite, epsomite and gypsum (Greenwood & Earnshaw, 1984). These dissolved minerals contribute to the mineral content of many drinking waters. Reported taste threshold concentrations in drinking water are 250–500 mg/litre (median 350 mg/litre) for sodium sulfate, 250–1000 mg/litre (median 525 mg/litre) for calcium sulfate and 400–600 mg/litre (median 525 mg/litre) for magnesium sulphate (NAS, 1977). Concentrations of sulfates at which 50% of panel members considered the water to have an “offensive taste” were approximately 1000 and 850 mg/litre for calcium and magnesium sulfate, respectively(Zoeteman, 1980) – in a survey of 10 -20 people.

Sulfates and sulfuric acid products are used in the production of fertilizers, chemicals, dyes, glass, paper, soaps, textiles, fungicides, insecticides, astringents and emetics. They are also used in the mining, wood pulp, metal and plating industries, in sewage treatment and in leather processing (Greenwood & Earnshaw, 1984). Aluminium sulfate (alum) is used as a sedimentation agent in the treatment of drinking water. Copper sulfate has been used for the control of algae in raw and public water supplies (McGuire et al., 1984).

Sulfates are discharged into water from mines and smelters and from kraft pulp and paper mills, textile mills and tanneries. Sodium, potassium and magnesium sulfates are all highly soluble in water, whereas calcium and barium sulfates and many heavy metal sulfates are less soluble. Atmospheric sulfur dioxide, formed by the combustion of fossil fuels and in metallurgical roasting processes, may contribute to the sulphate content of surface waters. Sulfur trioxide, produced by the photolytic or catalytic oxidation of sulfur dioxide, combines with water vapour to form dilute sulfuric acid, which falls as “acid rain” (Delisle & Schmidt, 1977). (World Health Organisation, 2004)

Phosphate rock in commercially available form is called apatite and the phosphate is also present in fossilized bone or bird droppings called guano. Apatite is a family of phosphates containing calcium, iron, chlorine, and several other elements in varying quantities.

Phosphorus is one of the key elements necessary for the growth of plants and animals and in lake ecosystems it tends to be the growth-limiting nutrient and is a backbone of the Kreb's Cycle and DNA. The presence of phosphorus is often scarce in the well-oxygenated lake waters and importantly, the low levels of phosphorus limit the production of freshwater systems (Ricklefs, 1993)Phosphates are not toxic to people or animals unless they are present in very high levels. Digestive problems could occur from extremely high levels of phosphate.

Phosphate will stimulate the growth of plankton and aquatic plants which provide food for larger organisms, including zooplankton, fish, humans, and other mammals. Plankton represents the base of the

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http://www.water-research.net/images/Krebdiag.GIF

Student number - B3007405food chain. Initially, this increased productivity will cause an increase in the fish population and overall biological diversity of the system. But as the phosphate loading continues and there is a build-up of phosphate in the lake or surface water ecosystem, the aging process of lake or surface water ecosystem will be accelerated. The overproduction of lake or water body can lead to an imbalance in the nutrient and material cycling process (Ricklefs, 1993). Eutrophication (from the Greek - meaning "well nourished") is enhanced production of primary producers resulting in reduced stability of the ecosystem. In situations where eutrophication occurs, the natural cycles become overwhelmed by an excess of one or more of the following: nutrients such as nitrate, phosphate, or organic waste. (Mr. Brian Oram, 2015)

Alkalinity (HCO3) is the measure of the buffering capacity of river water, with a high alkalinity results in a greater ability to neutralise acidic pollution from rainwater or wastewater. Water with a lower pH has a lesser ability to do this. Alkalinity doesn’t just only help regulate the pH of a water body but also the metal content. Bicarbonate and carbonate ions in water can remove toxic metals, such as lead, cadmium, by precipitating the metals out of solution.Alkalinity is mostly derived from the dissolution of carbonate minerals and from CO2 present in the atmosphere and in soil above the water table. HCO3 is dominate within the neutral range (pH 5-9), CO 3

2-

is above pH 9 and H2CO3 is below pH 5.Bicarbonate values in rivers range from <5 to 730 mg/L, with a median value of 126.4 mg/L.

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http://www.water-research.net/images/algae.jpg


Appendix 10: Planks equation (AAS)

The difference between the two orbits produces a wavelength that is emitted, worked out through Plancks equation (E=hc/)

E = energy difference between orbits H = Plancks constant C = the speed of light = Wavelength of photon (given out or absorbed)

Each of the elements have a unique wavelength, these fall within the UV-visible spectrum (160-800 nm).

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Appendix 11: AAS advantages and disadvantages

The advantages of using this technique: Simple Low capital cost Low running cost Few spectral interfaces

Disadvantages: Limited working range Matrix interfaces Single element analytical capability Unattended operation difficult

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Appendix 12 – Reasons why used specific settings for Ion chromatography Column type used was an IonPac As14A, this Analytic column was used because they have:

High efficiency with fast analysis (8 minutes) Improved peak shape, efficiency, and pH stability Meets or exceeds performance requirements by US EPA Method 300.0 (A) Simplified operation with AS14A Eluent Concentrate and Combined Seven Anion Standard

The column packings for ion chromatography consist of ion-exchange resin bonded to inert polymeric particles (typically 10 m),Injection loop: the sample is injected into the loop, when filled it switches back into the flow path. The sample is then injected directly into a mass spectrometer as part of a flow injection analysis (Ionsource.com, 2015).Eluent - allowing the automatic production of high purity ion chromatography eluents, through precise control of the electric current applied to the electrolysis of water to generate hydroxide and hydronium ions. Eluent eliminates the need to manually prepare eluents from concentrated acids and bases, except deionized water (Verma, 2013).

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Appendix 12 – Limestone formation - Nenthead

Cyclothem formations

In the Ordovician Period (510 and 408 million years ago (ma)) the Granite Batholith intruded the Alston Block. Fluctuation in sea level resulted in ‘Yoredale Cycles’ to arise in the Carboniferous shown in Figure 2 and 3 (North Pennines, AONB and European Geopark, 2010).

The Yordale Cycle:

Rock characteristics within the Yordale cycle:Figure 3 shows the rock types within the Yordale Cycle and attributes associated with the formation, such as water depth, thickness and common features found within the beds, such as common fossils in the limestones and marine shales, as well as coal fragments in the sandstones.

The Great Limestone varies in thickness frequently and to a dramatic scale. Varying from thirty-five feet in Northumberland to over eighty feet in Weardale. The local variation in limestone thickness occurs due to the development of limestone bands within overlying shales (Johnson, 1962). Bigger beds are better because limestones and sandstone are harder, therefore forming large open faults resulting increasingly economic mineral deposits, shown in Figure 4.

2

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5

1

2

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1

Figure 22: The formation of cyclothem sequences (from bottom to top). These reflect changing sea levels and the building up of river deltas. The column on the right shows the resulting rock sequence of limestone, shale, sandstone, coal & limestone (North Pennines - AONB 2015).

Figure 23: Cyclothem of the “Yordale Cycles”, the left hand side of the diagram shows the variable hardness’s and the degree of weathering that would be seen in a natural outcrop (Bulman, 2004)



































































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Appendix 14: calibration curves

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Documents

Report - Nenthead