## 4 Results and Discussion
### Construction Stage
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Chainage**} & \multirow{2}{*}{**Excavation Period**} & \multirow{2}{*}{**Ground Water Conditions**} & \multirow{2}{*}{**Rock Type and Condition**} & \multirow{2}{*}{**Chainage**} & \multirow{2}{*}{**Excavation Period**} & \multirow{2}{*}{**Ground Water Conditions**} & \multirow{2}{*}{**Rock Type and Condition**} \\  & & & **Date** & & & & **Period** \\ \hline
0 + 000–0 + 455 & Excavated & Dry & & 1 + 668–1 + 721 & February 2007 & Dry and damp & \\
0 + 455–0 + 600 & June 2006 & Flowing & 1 + 721–1 + 750 & March 2007 & Flowing & \\
0 + 600–0 + 658 & July 2006 & Dry and damp & 1 + 750–1 + 805 & March 2007 & Damp & \\
0 + 658–0 + 669 & July 2006 & Flowing & 1 + 805–1 + 880 & April 2007 &
\begin{tabular}{c} Dripping and \\ flowing \\ \end{tabular} & \multirow{2}{*}{**Dripping and**} \\
0 + 669–0 + 780 & July 2006 & Dry & 1 + 880–1 + 887 & May 2007 & Damp & \\
0 + 780–0 + 786 & August 2006 & Dripping & 1 + 887–1 + 923 & May 2007 & Flowing & \\
0 + 786–0 + 839 & August 2006 & Dry and damp & 1 + 923–1 + 960 & May 2007 & Damp & \\
0 + 839–0 + 843 & August 2006 & Dripping & 1 + 960–1 + 978 & May 2007 & Flowing & \\
0 + 843–0 + 869 & August 2006 & Damp & 1 + 978–2 + 030 & June 2007 & Damp & \\
0 + 869–0 + 873 & August 2006 & Flowing & 2 + 030–2 + 055 & June 2007 & Flowing & \\
0 + 873–0 + 884 & August 2006 & Dry and damp & 2 + 055–2 + 355 & July 2007 &
\begin{tabular}{c} Dry and \\ damp \\ \end{tabular} & \multirow{2}{*}{**Dripping and**} \\
0 + 884–0 + 889 & August 2006 & Flowing & 2 + 355–2 + 390 & July 2007 &
\begin{tabular}{c} Dripping and \\ flowing \\ \end{tabular} & \multirow{2}{*}{**Dripping and**} \\
0 + 889–0 + 910 & August 2006 & Damp & 2 + 390–2 + 400 & August 2007 & Dry & \\
0 + 910–0 + 925 & 2006 & Flowing & 2 + 400–2 + 418 & August 2007 & Dripping & \\
0 + 925–0 + 975 & September & Dry and damp & 2 + 418–2 + 438 & August 2007 & Damp & \\
0 + 975–1 + 021 & September & Dripping & 2 + 438–2 + 468 &
\begin{tabular}{c} September \\ 2007 \\ \end{tabular} & \multirow{2}{*}{**Dripping and**} \\
1 + 021–1 + 055 & October 2006 & Dry & & & \\
1 + 055–1 + 071 & October 2006 & Flowing & 2 + 700–2 + 834 & January 2008 &
\begin{tabular}{c} Dripping and \\ Dry and \\ damp \\ \end{tabular} & \multirow{2}{*}{**Dripping and**} \\
1 + 071–1 + 175 & 2006 & Dry & & & \\
1 + 175–1 + 217 & November & & & & \\
2006 & & & & & \\
1 + 217–1 + 237 & November & & & & \\
2006 & & & & & \\
1 + 237–1 + 246 & November & & & & \\
1 + 246–1 + 258 & December 2006 & Damp & & & \\
1 + 258–1 + 329 & December 2006 & Flowing & & & \\
1 + 445–1 + 459 & January 2007 & Damp & & & \\
1 + 445–1 + 459 & January 2007 & Flowing & & & \\
1 + 459–1 + 619 & February 2007 & Dry and damp & & & \\
1 + 619–1 + 636 & February 2007 & Flowing & 4 + 634–5 + 256 &
\begin{tabular}{c} September–9 \\ January \\ \end{tabular} & \multirow{2}{*}{**Dripping and**} \\
1 + 636-1 + 662 & February 2007 & Dry and damp & 5 + 256–7 + 700 &
\begin{tabular}{c} Dry and \\ damp \\ \end{tabular} & \multirow{2}{*}{**Dripping and**} \\
1 + 662–1 + 668 & February 2007 & Flowing & 7 + 700–7 + 828 &
\begin{tabular}{c} Dripping and \\ August \\ \end{tabular} & \multirow{2}{*}{**Dripping and**} \\
7 + 828–8 + 400 & 7 Jan–7 July & damp & & \\
8 + 400–8 + 509 & 6 September–7 & & & \\
8 + 400–8 + 509 & January & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Lowari Tunnel ground water conditions during the construction stage. Table 2 summarizes the results of the hydrochemical analysis of water samples collected from the right shoulder at chainage 1 + 662, which were compared with the 2017 World Health Organization (WHO) standards. All measured parameters were found to fall within the normal range, except for the pH value, which was observed to be low (5.21). The low pH value is attributed to the presence of CO2 inside the tunnel, which was quantified as 14,000 ppm by [43]. According to [45], higher CO2 concentrations are known to result in lower pH values.