The sewage system referred to in this chapter means the dedicated sewage systems in an industrial park.

Sewage systems shall collect wastewater or sewage in the area using dedicated ditches or pipes. However, this is not applicable to the wastewater or sewage of an enterprise that has acquired a surface water body discharge permit or a simple discharge permit document for such wastewater or sewage pursuant Article 20.
Sewage systems shall collect rainwater and the runoff wastewater other than that specified in Article 8 in the area using dedicated rainwater ditches or pipes. The ditches or pipes referred to in the preceding sentence shall not be used to collect the wastewater or sewage referred to in the preceding paragraph in a mixed manner.

Sewage systems shall conduct regular inspection and repair of the ditches and pipes referred to in the preceding paragraph.
For the regular inspection and repair referred to in the preceding paragraph, all the wastewater or sewage collection ditches or pipes shall be inspected and repaired at least once every three years. All the rainwater connection ditches or pipes shall be inspected and repaired at least once every three months. All the wastewater or sewage and rainwater drainages of the sewer-connected users shall be inspected at least once every month. And all the drainages of the sewer-connected users that only produce domestic sewage shall be inspected at least once every six months. Records shall be made for the results of the inspection and repair and shall be retained as a reference for three years.
Where the inspection result referred to in Paragraph 1 shows the incapability of separate collection specified in Article 96, such inspection result shall be, together with improvement measures, reported to the competent authority within one week after the inspection. Engineering improvement measures, if required, shall be completed within one year. An application may be made to the competent authority for an one-year extension of improvement, if necessary.

Sewage systems shall inspect the water consumption and wastewater or sewage volume of the sewer-connected users to ensure maintenance of reasonable balance. The inspection result shall be documented and retained as a reference for three years.
Where the inspection result referred to in the preceding paragraph does not indicate reasonable balance between the water consumption and wastewater or sewage volume, the sewage system shall find out the cause and take appropriate management measures.
In case the inspection referred to in Paragraph 1 indicates that a sewer-connected user is pumping groundwater without the approval from the competent authority of water supply, the local competent authority of water supply shall be informed of this violation.

Sewage systems shall take into account the characteristics of the wastewater or sewage of the sewer-connected users and the capability of the sewage treatment plant to specify the quality of the wastewater allowed to be discharged into the sewage system; sewage systems shall also take samples on a regular basis to test the wastewater of the sewer-connected users for its quality, and take appropriate management measures based on the test result. The test result shall be documented and retained as a reference for five years. However, this paragraph is not applicable to the water quality with respect to any sewer-connected user who only produces domestic wastewater.
The sampling and testing referred to in the preceding paragraph may be conducted in the internal water quality laboratory and shall be performed using the methods announced by the central competent authority.
The sampling and testing referred to in Paragraph 1 shall be conducted item by item according to the water volume of the sewer-connected user and the characteristics of the water quality. However, the instruction of the competent authority shall apply when it order a sewage system to increase the sampling and testing items or frequencies for the sewer-connected users based on actual need.
Itemized testing referred to in the preceding paragraph is prescribed below:
I. Sewage systems in science parks and specific petrochemical areas: Reported water quality items shall be tested on a regular basis and samples shall be taken and tested at least once every quarter.
II. Dedicated sewage systems in an industrial park other than those specified in the preceding subparagraph: Samples shall be taken and tested at least once every quarter for hydrogen ion concentration index, water temperature, chemical oxygen demand and suspended solids; samples shall be taken and tested at least once every six months for other water quality items to be tested and reported on a regular basis.
For the water quality of the user connected to a sewage system, all the items, except for hydrogen ion concentration index, water temperature, chemical oxygen demand and suspended solids, whose test results are lower than the effluent standard for two consecutive tests are exempted from retests.
Sewage systems shall regularly guide and inspect sewer-connected users to understand the function and operation of their wastewater or sewage pretreatment facilities, and shall take appropriate management measures based on the result of the inspection. Records shall be made and retained as a reference for five years.

Sewage systems shall regularly take samples of wastewater or sewage at appropriate confluence points and test such samples for their water quality. Records shall be made and retained as a reference for five years.
The sampling and testing for water quality referred to in the preceding paragraph shall comply with Paragraph 2 of the preceding article.
Where the water quality sampling and testing results referred to in Paragraph 1 discovers incompliance with the water quality requirements for the sewer-connected users specified in Paragraph 1 of the preceding act, the sewage system shall find out the cause and request the sewer-connected user concerned to make improvement, and shall take inflow water quality/water volume buffering and blending measures to maintain the quality of the inflow water within the normal treatment rage of the wastewater or sewage treatment facilities.

Sewage systems shall analyze and review water volume and quality for their variation every month, and assess the collection and treatment capability of the sewage system. Where the assessment and review indicate possible inadequacy of collection and treatment capability, a written notice shall be sent to the municipality or county (city) competent authority and response measures shall be taken. Engineering improvement measures, if required, shall be completed within one year. An application may be made to the municipality or county (city) competent authority for a one-year extension of improvement, if necessary.
Records shall be made for the monthly analysis and review of water volume and quality variation, assessment of collection and treatment capability, and implementation status of response measures and retained as a reference for three years.

As of 2015, dedicated sewage systems in an industrial park shall submit the self-assessment report of the previous year to the municipality or county (city) competent authority before the end of June every year. The report shall at least contain the following information:
I. Sewage treatment plant’s inflow and outflow water quality, dosage of agents, power consumption, sludge production volume, permit (document) registration items, and the data comparison results of the latest three years.
II. The number of enterprises, sewer-connected enterprises, and self-discharge enterprises in the industrial park.
III. Allowable utilization, design utilization, and charge rate based on the volume of water to be treated.
IV. Equipment availability, equipment damage response measures, annual repair and engineering improvement.
V. Imposed punishments and improvement measures in a year.
VI. Implementation status of the matters to be completed according this chapter.

Sewage systems may discharge through emergency discharge points to rescue personnel or salvage treatment facilities. Such emergency discharge points are limited to the overflow outlets of the inflow well or other facilities with similar functions, and wastewater or sewage can be discharged only after the Issuing Authority gives its approval.
Cumulative water measuring facilities and gate valves shall be set up for the emergency discharge points. Gate valves shall be sealed with lead sealing by the competent authority and shall not be destroyed; the seal of a gate valve may be removed only when emergency discharge is required.
When discharging wastewater or sewage through an emergency discharge point referred to in Paragraph 1, the sewage system shall report to the competent authority within one hour after the discharge; records shall be made and retained as a reference for three years.
Where using an emergency discharge point more than twice within six months, the sewage system shall propose an written improvement plan for the abnormal inflow, submit it to the competent authority for approval, and implement the plan within the scope of the approval.

Sewage systems shall in any of the following circumstances submit a total pollution reduction management plan pursuant to the regulations of the competent authority. The plan shall be reviewed and approved by the central competent authority in consultation with the central authority in charge of the relevant industry and the municipality or county (city) competent authority, and shall be implemented within the scope of the approval:
I. The discharge wastewater or sewage contains substances harmful to the health and the total discharge volume increases for five consecutive years.
II. The actual average discharge volume of wastewater or sewage reaches more than 50,000m3/day within six months and the receiving water body of the effluent is deemed by the competent authority as seriously polluted.
III. The competent authority conducts environmental pollution investigation with respect to the receiving water body and finds, based on the investigation result, that discharge of wastewater or sewage into the sewage system may bring about serious pollution.
The total pollution reduction management plan referred to in the preceding paragraph shall contain the following items:
I. Wastewater or sewage discharge characteristics.
II. Receiving water body impact analysis.
III. Analysis of sewage collection management measures.
IV. Assessment of the sewage treatment plant for the function and operation status of its facilities.
V. Reduction goals and schedules of the total pollution reduction management.
VI. Concrete implementation measures and scopes of the total pollution reduction management.
VII. Effectiveness assessment and verification of the total pollution reduction management.