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2017 Project of investigating and verifying pollution for Taichung soil and groundwater

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Taichung Environmental Protection Bureau (TCEPB) has carried out the work to manage the current quality of soil and groundwater, including regular monitoring, emergency treatment and investigation, confirmation for soil gas near underground storage tanks, testifying contaminated sites, management and maintenance of monitoring wells, and educational campaign. In 2017, TCEPB has commissioned AECOM (the team) to run “2017 Project of contamination investigation and confirmation for Taichung soil and groundwater” (the “project”), and the working period was from January 24th 2017 to December 31st 2017. The following abstract is the interpretation of the project. 1.Investigation of highly potential contaminated farmland According to Article 6 in Soil and Groundwater Pollution Remediation Act, the regular monitoring has been imposed to farmlands. There were 90 parcels under investigation with totally 90 collected samples and two parcels (DF004-B and DF005) in Dajia district was found that the zinc concentration is higher than the farmland control standards. Although the examination results from Dajia and Dali districts were below control standards, they were higher than the monitoring standards, suggesting the surveillance should be continued. The results by characteristic radar index showed that the concentrations of nickel, chromium and zinc were the characteristics in 2nd water supplement of Datuliao waterway and in 1st and 4th water supplement of Zhancuoyuan waterway. On the other hand, the concentrations of nickel, chromium, zinc and copper were the characteristics in 2nd water supplement of Zhancuoyuan waterway, indicating the sources of pollution were different. The results in Dajia farmlands showed that the concentrations of nickel and zinc were the characteristics. Our team suggested that the supervision and verification plans for 28 farmlands exceeding control standards should be drawn up as soon as possible in order to remove them from contamination control list. 2.Investigation of highly potential contaminated groundwater In 2017, we had successfully completed groundwater sampling for 78 wells in both drought and monsoon seasons, including Taichung Export Processing Zone (TEPZ), Taichung Dali GuangZheng road area, large-size storage tank area of Taichung harbor, Taichung Industrial Park, Aerospace Industrial Development Corporation (AIDC), Sinon Corporation (Wang Tian factory), Tali Sunko Ink Co., Ltd, and Da Jia Youth Industrial Park (DYIP). The results showed that groundwater at Taichung Industrial Park, Da Jia YouthIndustrial Park (DYIP), Taichung Dali GuangZheng road area exceeded the control standards. The detail results are as follows: a. Taichung Industrial Park The chromium concentrations at B00343 monitoring well was 0.637 mg/L in drought season and 0.855 mg/L in monsoon season, respectively. Although the chromium concentrations in 2017 were lower than the ones in 2016, the investigation results showed that the chromium concentrations still exceeded the control standards, which indicated chromium pollutant from this area still had impact on the quality of groundwater at downstream area. Investigation results of monitoring wells B00343, B00365, B00403 and B00424 inside Taichung Industrial Park’s early-warning network in drought season showed that slight amount of trichloroethylene (TCE) was found. The concentration of trichloroethylene (TCE) at monitoring well B00424, which is at the northernmost location, exceeded the baseline value of confirmation(查證基準值) (0.006mg/L). It is likely that B00424 was affected by upstream no. 33, Xiehe section, Xitun district. Close attention to this site is necessary. b. Taichung Export Processing Zone (TEPZ) and its perimeter L00094, L00095 and L00096 are three monitoring wells outside the TEPZ. VOCs concentrations of L00094, the furthest one from TEPZ, were higher than those of L00095, which means the contaminant from TEPZ still affected the quality of groundwater outside TEPZ. Monitoring operation should be constantly taken to observe the groundwater outside TEPZ after improvement method was carried out (加藥) in TEPZ by management office(管理處) and quality improvement team(改善業者). c. Dajia Youth Industrial Park (DYIP) and surrounding area The nickel concentration at B00373 exceeded the control standards in drought season but not in monsoon season, and the nickel concentration at B00429 exceeded the control standard. There is a gap with 10 meters width between B00373 and B00429 and the distance between them is 80 meters. Recently, these two monitoring wells had nickel content usually higher than the control standard as B00429 is 20 meters far from sewage outfall of Tai Zi Ji Co.Ltd.,. The company was under inspection by Article 7-5 in Soil and Groundwater Pollution Remediation Act and had been in control list because of exceeding nickel concentration in soil. Although it had been removed from control list by January 18th 2016, the contaminant may come from unsaturated zone, upstream area, electroplating process area or other sources. Close attention to this site is necessary. d. Taichung Tali Guang Zheng road area Monitoring well B00113 is located at downstream area of three contaminated sites in Taichung Tali Guang Zheng road area. It exceeded the control standards in both monsoon and drought seasons. Moreover, the chromium concentration at B00238 exceeded the control standard in monsoon season in 2017. The value had been ups and downs between the monitoring standard and control standard since 2013. Because Zheng You Co., Ltd. and Bao Jing Company didn’t conduct pumping operation properly and thus, the plume was spread to downstream monitoring wells B00113 and B00238, causing chromium concentrations over the control standard. The counselor of EPA and Chief of TCEPB held a meeting with Zheng You Co., Ltd. at June 20th for demanding Zheng You Co., Ltd. to inspect the plating tank. Otherwise, the current operation would merely prevent plume from being spread rather than improve the overall condition. e. Dajia Youth Industrial Park (DYIP) The monitoring results showed that L00055 and L00073 in drought season didn’t exceed the monitoring standards. Monitoring well L00073 near Prim Oil Chemical Service Corporation (POCS) was found vinyl chloride concentration at 0.00606 mg/L as a result of slight affect by POCS. f. The Taichung City Precision Machinery Innovation Technology Park In 2017, downstream monitoring well B00046 in the park didn’t exceed the monitoring standards. Self – monitoring results of GW05 and GW06 were well-documented in this report. It showed that trichloroethylene (TCE) concentrations of GW05 and GW06 had not been exceeding the monitoring standards for three years but over the baseline value of confirmation. There was no investigation on contaminant source in Park Development of Project Environmental Impact Statement or outsourcing projects, suggesting the surveillance of downstream area be continued. To avoid unexpected contamination incident, passive diffusion bag sampler method would be conducted at GW-05 and GW-06 when necessary. g. Other areas Aerospace Industrial Development Corporation (AIDC), Sinon Corporation (WangTian factory), Taichung Tali Sunko Ink Co., Ltd. and Taiwan UL FengFu gas station had been in improvement stage and all of the downstream monitoring wells did not exceed the control standards. 3.Well monitoring and maintenance management In first half year, the team had completed exterior and interior patrol and inspection for 198 monitoring wells and 209 in each half year. Other results included condition evaluation for 37 wells, i.e 4 area wells and 33 site-placed wells , maintenance of 18 monitoring wells, repairing body facility for 9 wells, re-developing 19 wells, removing unexpected substance and inner photography for 5 wells, and termination on 10 wells. The team suggested to repair or maintain L00012, L00151 and B00113 depending on its damage. Besides, L00005, L00169 and B00403 were found to have unexpected substance inside. The team assisted TCEPB to draw up grading system for monitoring well interior maintenance. The result suggested that there were 33 wells in need of further evaluation in order to understand the situation inside the wells since their monitoring wells score were higher than 14. 4.Verification and supervision of pollution site The team had completed 893 times patrol and inspection since January 2017, and ended up in November 2017 according to the contract (once per two months). In April, the team found Zheng You Co., Ltd.(正佑公司) was not able to meet the effluent standards and thus inspected them again with enhanced monthly audit. However, they still couldn't improve the situation to meet the requirement and had been fined to ask them for immediate improvement. The chromium concentration of Bao Jing Company (保勁地下水) was found to increase unexpectedly so that the TCEPB had already formally informed Bao Jing Company (保勁地下水) to initiate emergency response to address and improve this issue and see if it wascaused by their improper factory operation. As both effluent pH and chromium concentration from Ruey Chang Printing & Packing Foil Co., Ltd. had not conformed to effluent standards in 2016, the team assisted TCEPB to conduct enhanced weekly audit and examination and the results were qualified. In addition, the team had assisted TCEPB to review 109 reports. The original contract requested to complete 5 sites confirmation. The team planned to carry out the confirmation in HouLi farmlands additionally, but didn’t accomplish because of some issues over soil offsite. The project in 2017 had confirmed only 1 out of 5 sites was qualified. The reasons of failing to qualify might be imperfect site investigation in early time, suggesting that the sites should be kept in control list to address the contaminated extent clearly. 5.Inspection of underground storage tank There were 316 (January), 317 (May) and 318 (September) underground storage tank industries that had to complete online application, separately. The team finished the verification in February, June and September. Both the percentage of application and verification were 100%. According to the contamination potential classification of underground storage stank completed by the team, 15 underground storage with high potential of contamination had been selected for verification. Among the selected, there were 9 stations at which concentrations of soil gas were still higher than regulatory warning standards and 3 of them belonged to level A, 1 of them belonged to level B1 and 1 of them was found level B1 in two sequential inspections. Apart from the results of the 3rd inspection integrated into the surveillance next year, the results of 1st and 2nd inspection launched the soil and groundwater investigation according to EPA’s rating and showed no detection of TPH and BTEX. 6.Emergency treatment work As of 18th December 2017, the team had completed 12 soil and groundwater emergency treatment works, including 2 farmlands in Dali and Xi Tun, 2 factories in Wu Chi and Daya, 4 lands in Dajia, 1 contaminated site in Shenang, Shunlifa gas station, Zhonghua gas station, Dalian gas station, Zhonggang container transfer station, guanlian industry park and drainage area in Houli. There were 3 cases found exceeding the control standards and was 1 case found exceeding the monitoring standards. The total funds was 786,843 NTD. 7.Other achievements The team assisted TCEPB holding 1 groundwater storage tank laws explanation session and 1 environmental regulation workshop. The amount of participants conformed to the contract and the results of questionnaire showed high satisfaction. As Report of Investigation and Detection in Soil Pollution (土測報告) would be reviewed by TCEPB, the team established a process of review and memo and set up a website to advocate Article 8 and 9 in Soil and Groundwater Pollution Remediation Act. Besides, 70 reports were 100% reviewed and the team reduced the working time from 66 days to 45 days.
Keyword
Soil and Groundwater, Investigation of High Pollution Potential Areas, Monitoring Wells Maintenance Management
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