The purpose of this study is to estimate the wave height located at the front face of the offshore refracted breakwater when the trench is dredged in the exterior region of the breakwater at various depths. The problems that arise with regard to the different obliquely incident wave field involve having two-dimensional planes and having the configuration of the trench region designated by a single horizontal rectangular system. The numerical approach involves applying the Green function based on the boundary integral approach. The results of the present numerical works are illustrated. The ratio of the wave height reduction at the front face of the refracted breakwater is shown to be more than 25% due to the trench's effect on the seabed. The corner of the refracted breakwater is where the wave energy is concentrated, and through utilizing the trench, the wave energy can be subdued to reduce the damage on the breakwater. The trench brings about a reduction in wave amplitude and wave energy in, around, and directly downstream of the trench.

The FEMWATER model is a three-dimensional finite element model that can simulate both groundwater flow and mass transport at the same time, and so by using this FEMWATER model seawater intrusion was simulated and the results were compared to observation data. By using the observation data, a conceptual model was made of 3 layers based on the type of soil, and the hydrogeological parameter was selected. There are two types of dispersivities: longitudinal dispersivity and transverse dispersivity. Longitudinal dispersivity was calculated by Xu and Eckstein's method (1995) and the transverse dispersivity was put at 3=10 of the longitudinal dispersivity for the simulation. The electrical conductivity suggested by Freeze and Cherry (1979) and the correlation with total dissolved solids, TDS, was used to classify the state of the water. Upon analyzing the depths at 15 m, 30 m, 60 m, and 90 m, occurrence of seawater intrusion near the ground surface was limited to the vicinity of the coastline, but as the depths became deeper, seawater intrusion expanded inland. From these results we can come to the conclusion that in order to prevent seawater intrusion there needs to be sufficient preliminary examination.

Contamination of soil with heavy metals drained out from twenty eight abandoned mines in the southwest regions of Korea has been investigated. Utilizing various statistical techniques, the goal was to evaluate and analyze pH and the contamination with Arsenic, and the following six heavy metals: cadmium, hydrargyrum, lead, nickel, chromium, and zinc. Contamination levels of heavy metals were determined depending on the depth of the soil. Results indicated that the subsoil and the surface soil both were strongly contaminated with lead and arsenic. Furthermore, the subsoil also contained much nickel. In forest regions, high levels of lead and arsenic, whereas in all regions high levels of zinc have been detected.