Modeling of Groundwater Pollution by Former Seawater in Submarine Groundwater Discharge Driven by Saltwater Intrusion

• Autorzy: Al-Taliby Wissam , Dekhn Hadeel

Identyfikatory

DOI

10.12911/22998993/144393

• Języki publikacji: EN

Abstrakty

EN

Coastal aquifers are usually vulnerable to contamination by saltwater intrusion. The degree of contamination depends on the amount of former seawater intruding the aquifer as submarine groundwater discharge (SGD). A three-dimensional numerical SEAWAT model was developed to provide insights to the responses of saltwater intrusion and amount of seawater portion of SGD, to groundwater withdrawal from four wells at different spatial locations. The results showed that saltwater wedge encroachment varies with a withdrawal rate and well location. Increasing withdrawal rates from 0.165 m³/s to 0.53166 m³/s resulted in a noticeable increase in wedge encroachment into the aquifer from 589 m to 1319 m, respectively, regardless of the distance from the coastline. However, higher withdrawals from the wells closer to the coastline caused the hydraulic head near the seaside to drop below the terrestrial head, causing the saltwater wedge to be pushed back toward the sea. Simulations also showed that a coastal well might act as a hydraulic barrier that prevents the brackish zone from moving further inland, which is critically important in terms of groundwater management. Seawater contributed from 5% to above 33% in SGD. Although the withdrawal rates from Well 3 were 10 to 20 times larger than the Well 2 rates, the seawater contribution associated with Well 3 was about the same. This is attributed to the horizontal vicinity of Well 2 to the seacoast boundary compared to Well 3 even though Well 3 is deeper than Well 2, demonstrating that it is the horizontal location that governs the amount of abstracted former seawater.

Słowa kluczowe

EN

saltwater intrusion; SEAWAT; submarine groundwater discharge; groundwater

• Wydawca: Polskie Towarzystwo Inżynierii Ekologicznej ; Lublin University of Technology
• Czasopismo: Journal of Ecological Engineering
• Rocznik: 2022
• Tom: Vol. 23, nr 2
• Strony: 166--175
• Opis fizyczny: Bibliogr. 32 poz., rys., tab.

Twórcy

autor

Al-Taliby Wissam

• Department of Environmental Engineering, College of Engineering, University of Babylon, Babylon 51001, Iraq

• https://orcid.org/0000-0003-1104-0078

autor

Dekhn Hadeel

• Housing, Municipalities and Public Works, Soil Investigation Section, Construction Laboratories, Ministry of Construction, Babylon 51001, Iraq

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