In order to prevent soil and groundwater from contamination, the local competent authority must regularly investigate and exam the quality of soil and groundwater in its own jurisdiction and deal with the petitions. Therefore, Yilan Environmental Protection Bureau (EPB) has been continuously monitoring the potential sites of contaminated soil and groundwater in the region, including industrial complex and communities in Longde, Lize, and Meizhou, as well as other underground storage tanks (UST). Additionally, the inspection, verification and control measures has been implemented over restricted contaminated area. The Yilan EPB has commissioned Taiwan AECOM Co., Ltd (the “team”) to be the chief executive of the “2016 Investigation and Verification of Soil and Groundwater Contamination in Yilan County” project (the “project”). All scopes of work in the project has been accomplished and every assignment was flawlessly on schedule. Hereby the final report is submitted to the EPB following its inspection over the work.
This year, a total of 9 sites, where the contamination in soil exceeds the control standard, were investigated. The result shows that the concentration of heavy metals were found to exceed monitoring standards of food crops in some of the lands fertilized using animal manure and lands in Gonglao Section of Zhuangwei. In addition, when crop lands in Gonglao Section of Zhuangwei were investigated, the sediment of water inlet and upstream, as well as the underground water were also investigated. Results showed that the arsenic in the sediment all exceeded the “Sediment Upper Limit”, and it is possibly due to long-time irrigation using arsenic-containing underground water.
For sensitive receptors near Lucky Cement Co., including Dongao elementary school, camp sites and farmlands along the Dongaobei River, as well as bare lands around the residential area, sampling work was performed. Also, one sample point was set outside the dust-affected area of Lucky Cement Co. as a background reference for soil heavy metals and dioxin analysis. No heavy metal was detected or exceed the soil monitoring standards; the highest of dioxin was 2.76 ng I-TEQ/kg, 0.00276 times of that of the monitoring standards, not exceeding the standard as well. The team further compare the dioxin concentration near Lucky Cement Co., and it was found that the dust from the operation of Lucky Cement Co. may affect the surroundings.
In the survey of sediments of rainwater discharge outlets of the highways, it mainly focused on the sections that may be the most highly contaminated, the Toucheng-Yilan section and the Yilan-Luodong section, sampling 3 and 2 points respectively. The results showed that although heavy metals such as mercury, copper, nickel, zinc and arsenic were detected to exceed the lower limit of the sediment quality index of the sediment, with zinc also exceeding the upper limit, after comparing the results of sediment of the irrigation channel from the Irrigation Association, it was found that the survey results are similar to the background except for zinc.
The team had completed, as contracted, a total of 2 times of quarterly work of the checks and maintenance of regional and on-site monitoring wells for the condition assessment on 13 monitoring wells; according to the results, 5 of them went through the maintenance after the assessment, and 6 of them went through the well development again followed by camera shooting inside the well to assure of tidiness.
Sampling work of all 30 wells has been done in May, 2018, and no results exceeded the control standards, and 12 of them reached the monitoring standards, mainly ammonia and TOC.
As for the monitoring of the landfill site, no groundwater exceed the control standards. It is common that all landfills detected ammonia nitrogen, exceeding monitoring standards, including Wujie Landfill, Suao Landfill, Samsung Landfill, Jiaoxi Landfill, Yilan City Jianlan Section, Dongshan Landfill and Yuanshan Regional Landfill. The Wujie Landfill, Su-Ao Landfill, Dongshan Landfill and Sanxing Landfill all exceeded the monitoring standards in total hardness, chloride salts and total dissolved solids. For raw water, Wujie, Su-Ao and Samxing Landfill all detected ammonia nitrogen, exceeding the discharge water standard. Suspended solids of Sanxing Landfill exceedied the discharge water standard as well. In addition, Su-Ao Landfill is also high in pH, suspended solids, chemical oxygen demand, exceeding the discharge water standard.
The team has carried out the monthly inspection over restrained sites for the progress of improvement and the latest condition in hand and evaluate the predicted effects for the site where the remediation plan has been accomplished. Currnently, there are totally 10 sites that has completed post-improvement verification, and 5 of them (Land No.1197 of Yicheng 4th section in Dongshan, Land No.734-1 of dongyue section in Nanao, Land, No.1049 of Kaisuan section in Yilan, Land No.549 of Bayalin 2nd section in Toucheng, and Land No.10 of Nanan section in Suao have been removed from the control list.
A survey was conducted on the sediments around the potentially-contaminated factories; a total of 25 factories were surveyed and sediment of 10 of these factories were sampled. The test results preliminary evaluated that there were 4 factories that are relatively with high contamination, including Shunfa Timber Co., Ltd., Nonghe Enterprise-Wujie Factory and Yiguan Industrial Co., Ltd. It is suggested that the EPB can focus on the mentioned factories for on-site checks and follow-up investigations.
According to the results of the “Determination of Sediment around the Potentially-Contaminated Factories” in 2017, 7 factories in Yilan County were selected for on-site interviews. Based on the results of the on-site interview, the De-hsieh and Cheng-you company were selected for soil contamination verification. The results showed that TPH and zinc concentration of De-hsieh Company have exceeded the control standards.
The team has conducted soil and groundwater contamination verification for 3 announced firms that are with environmental violation records, and the Meliwei Semiconductor Co., Ltd Yilan Factory. Leze Plant of Taiwan Semiconductor Co., Ltd. and Yaohua Technology Co., Ltd. were selected for on-site investigation and the interview. The results showed for soil and groundwater, none of these 3 factories exceeded the monitoring standards.
This year, the team has conducted verifications of soil contamination at 7 points where the Xuanlong Company used to pile up the output of Luodong Iron and Steel Company. The results showed that the heavy metals in Land No.831 of Aicheng Section in Suao, Land No.2011 of Beifu Secion in Dongshan, and Land No.690 of Hukou Section in Suao exceed the control standards.
Currently, the team has been associate with EPB to complete the UST reports of Q3 in 2017 (from Sep to Dec), Q1 in 2018 (from Jan to Apr) and Q2 in 2018 (from May to Aug), with 100% of inspection. Organizing the issues coming up frequently, the main issues include “declaration of soil and air monitoring items” and “operation of online system and others”. Brief sessions for Precautions and Regulation of Soil and Underground Water Contamination for UST has been held on May 7th, 2018 for such issue.
There had been 12 Lorries going through the examining work of soil-rock importing management from March to November 2018. Amid the use of XRF screening, the selected samples were analyzed for heavy metal content and the results indicated zero sample exceeding the monitoring standards of crop soil. Additionally, on March 3rd, with the EPB and staff from Nanou Town Office, the team has executed the on-site check at the construction produced soil backfill point in Aohua Cemetry, and 6 soil samples were collected to undergo XRF screening; the results was much lower than the regulatory standards. The examining work of soil-rock importing management has been implementing for 2 years and most of the business owners or stack-holders have been precautious for those soil from unknown sources since their awareness of the EPB’s examination. Thus, with efficiently managing the investigating resources and funds, it is recommended that the EPB can particularly rely on XRF screening for determination in which the sample should be transferred to laboratory for standard analysis and further tracking if there was 1 element exceeding the monitoring standard.
In this there have been 3 open conferences for interpreting relevant Acts of prevention of soil and groundwater contamination (total audience number: 306), 5 educational sessions (total audience number: 335) and 6-hour training courses for EPB’s staff. The team has also assisted the EPA and EPB for the 2018 National Soil and Water Seminar on September 11 and 12, 2018.
For the evaluation of performance indicators, the team has assisted the EPB in proposing key points and measures of the 2018 evaluation for program management, contaminated site management and administrative works, highlighting the determination of the EPB in contamination verification and remediation and showing the effectiveness of soil and underground water implementation. In addition, the team also assists the EPB in setting relevant weights for assessments, giving higher weights to projects with higher levels of confidence, in order to achieve the highest scores in addition to the principle of mastering the basic scores, as of December 27, 2018, the score of EPB's performance was 89.57.
