History of the Site
Cadastral No. 279 is an undeveloped land with an area of 64,485 m2. It is located in Nazi District, Kaohsiung City, with the Kaohsiung Refinery of CPC on the west and nearby the Houjin creek on the east.
In 2014, the EPB (Environmental Protection Bureau) investigated and verified that BTEX and TPH (Total Petroleum Hydrocarbon) in the soil and TPH in groundwater exceeded law standards. Therefore, EPB announced Cadastral 279 is a soil and groundwater pollution control site. Since Apollo undertakes the site in 2019, Apollo has continued to carry out SVE/AS in-situ remediation, and the goal is to achieve site delisting within 4 years.
Pollution in figures
Over 40% of the site, approximately 27,500 square metres, is contaminated. The maximum concentrations of various contaminants in the soil are as follows:
- Benzene: 74.4 mg/kg
- Toluene: 989 mg/kg
- Ethylbenzene: 1,230 mg/kg
- Xylenes: 3,730 mg/kg
- Total petroleum hydrocarbons (TPH): 14,700 mg/kg
Highest concentration of contaminants in groundwater:
- Benzene: 0.443 mg/L
- TPH: 15.6 mg/L
Apollo Technology Added Value
The main containment in the site is low-carbon TPH, which is easily volatile and biodegradable. In addition, the geological conditions are mainly sandy soil (high permeability), which is a well-permeable formation, so it is suitable to apply in-situ physical or biological remediation, such as Soil Vapor Extraction (SVE), Air Sparging (AS) and Enhanced bioremediation (EB).
Generally, the main factor that is most possible to affect the effectiveness of in-situ remediation is the heterogeneous geology, which may cause the effect to be less than expected and draw the remediation time out. Therefore, assess the area of the heterogeneous texture, and strengthen improvement is very important. In Apollo’s experiences, there are many sites with heterogeneous geological conditions that seriously affect the performance. After assessing the site characteristics and applying enhancement in specific areas, all the site remediation performance got great improvement.
Furthermore, Apollo has experience in managing large sites. Cadastral No. 279 is a large-scale site using in-situ methods. Apollo has to operate and maintain more than 400 remediation wells. Proper management of all the wells, ensuring their functions and effective operation, plus immediate improvement is another important key to achieving the remediation goal.