Nuclear Safety and Security Commission

The NSSC Held the 116th Meeting of the Commission

■ The bill to modify the construction permit and operating license of nuclear facilities was discussed and passed.

The Nuclear Safety and Security Commission (Chairman Uhm Jaesik, hereinafter referred to as the NSSC) held the 116th meeting of the Commission in writing*, and passed the ｢bill to modify the construction permit and operating license of nuclear facilities｣.

* To prevent the spread of Corona 19, this meeting was held for 5 days from Mar. 23 (Mon), 2020 to Mar. 27 (Fri) in writing in accordance with Article 14 of the ｢Rules on the Operation of Nuclear Safety and Security Commission Meetings｣.

In order to improve the safety of the Hanbit Unit 5 and 6, the bill will allow the modification of the Final Safety Analysis Report and the Technical Specifications to ① replace the steam generators* equipped with Alloy 600 tubes with the ones with Alloy 690 tubes, which are more resistant to corrosion, and to ② apply Alloy 690 materials on the upper reactor head penetration using weld overlay techniques.

* Steam generators produce steam from the heat generated by the reactor and drive turbines and power generators.

As for the modifications related to the Shinkori Unit 5 and 6, the bill will revise the Preliminary Safety Analysis Report to reflect the design details confirmed after the construction permit, such as ③ changing the shape of the opening of the outer wall of the auxiliary building and ④ adding pillars to the building for component cooling water heat exchangers.

The NSSC Announced Result of Investigation on Leakage of Radioactive Materials from Natural Evaporation Facility of the KAERI

The Nuclear Safety and Security Commission (Chairperson Uhm Jaesik, hereinafter referred to as the "NSSC") finalized the investigation, which was started on January 21st, of the "Korea Atomic Energy Research Institute (President Park Won-seok, hereinafter referred to as the “KAERI”) about the incident involving the “leakage of radioactive materials from a natural evaporation facility”. On March 20th, the NSSC notified the Ministry of Science and ICT (Minister Choi Gi-yeong, hereinafter referred to as the “MSIT”), the designating authority of the KAERI, and the KAERI, and requested for follow-up actions.

The natural evaporation facility was licensed (in 1989) as a nuclear spent fuel processing business by the former Ministry of Science and Technology in accordance with Article 35 (2) of the Nuclear Safety Act. Therefore, the MSIT will seek and impose administrative actions according to Article 36 (1) of the same act and the KAERI will establish detailed implementation plans of the safety enhancement plan and report them to the NSSC.

The NSSC dispatched a team of investigators from the Korea Institute of Nuclear Safety (President Son Jae-yeong, hereinafter referred to as the “KINS”) to the site. The team looked at the inspection records, facility operation records, radiological environment survey records from the licensing stage to now, CCTV images, and simulation experiments. The results are summarized below:

【Root cause of the leakage of radioactive materials】

The root cause of the leakage of radioactive materials from the natural evaporation facility is that the drainage system had been constructed and operated differently from the design permitted by the MSIT.

The natural evaporation facility obtained the permit for its design that had a closed circuit where the facility receives very low level of liquid radioactive waste (below 185Bq per liter) into the basement storage tank (860,000 liters), send the waste up to the supply tank on the third floor then to the evaporation stream stretching long on the second floor for the waste to naturally evaporate by sunlight, and finally send the remaining waste back to the basement storage tank.

At the actual site, however, the floor drainage tank (600 liters), not included in the permitted design and connected to the outside pipes, was installed in the basement. The facility has been used (since its construction in August 1990) every year from April to November with some of the drains on the first floor connected to the floor drainage tank.

The operators so far have not realized that the floor drainage tank (600 liters) had been installed separately from the basement storage tank (860,000 liters) and thought that all drains were connected to the basement storage tank and circulating in the close circuit.

【Result of the investigation on the discharged amount】

As a result of investigating the discharged amount through CCTV images and simulation experiments, it was found that about 510 liters of liquid radioactive waste was leaked to the outside while the waste water collecting basin on the second floor overflowed due to flawed operation with the valve overly opened after the filter was replaced on September 26th, 2019.

In addition, it was confirmed that in the process of retrieving all liquid radioactive waste into the basement storage tank after the operation of the facility was stopped every November to prevent freezing during winter, some of the waste (470-480 liters annually) was introduced into the floor drainage tank, then leaked to the outside.

【Impact assessment of the outside environment due to the leakage of radioactive materials】

As a result of reviewing the radiological environmental impact assessment records independently measured by the KAERI and the KINS on a regular basis every year, it was confirmed that all of the records of the stream water were below the minimum detectable activity (MDA) even though radioactive materials were discharged every year in November.

As for the radioactive concentration of the soil in the stream in front of the main gate of the KAERI, it is judged that the effect to the outside has been minimal as no notable records were found except for the record, 25.5 Bq/kg, which was measured in the fourth quarter of 2019.

The KINS investigation team confirmed that no peculiar records had been left in the quarterly radiological environment surveys of the surrounding environment of the KAERI. This is because the radioactive materials, such as Cesium-137, are easily absorbed to soil and while the released waste water flowed 1.5 kilometers, starting from the natural evaporation facility then through rainwater pipes inside the KAERI site and 10 manholes to Deokjin Stream in front of the main gate, the radioactive materials were absorbed to the soil inside the KAERI site, barely reaching the stream, including Deokjin Stream, and stream soil.

However, the reason for the unusual value in the fourth quarter of 2019, measured after the discharge (510 liters) due to inexperienced operation on September 26th, 2019, was the high precipitation (200 mm) between October and November of 2019, which led to some radioactive materials leaking outside the site.

※ Average precipitation in December after the discharge (470 ~ 480 liters) around November for the past 30 years is 30mm

Most of the discharged radioactive materials such as Cesium-137 are presumed to be retained on the surface of rainwater pipes and soil in the manholes within the KAERI. However, under the assumption that all of the radioactive materials have been leaked to the outside, the annual dose is assessed to be:

① 3.24×10-7 ~ 4.25×10-5 mSv based on the discharged amount in 2019

② 2.08×10-6 ~ 2.72×10-4 assuming that all of the discharged amount over the 30 years were released at once

Those values were found to be about 1 in 3 million to 1 in 3,700 of the effective dose limit for the public (1 mSv).

The NSSC concluded that the root cause of this incident is the lack of an institute-wide management system to fulfill primary responsibilities for nuclear safety as a licensee, inadequate design-based configuration management, manual operation system, and absence of safety awareness.

The NSSC ordered the KAERI to establish detailed implementation plans for the comprehensive safety enhancement plan for the KAERI facilities that include conducting a full investigation to see if there are any differences between the licenses and construction drawings of the KAERI's over 100 nuclear and radiation facilities and the current state of the facilities, increasing the number of points for radiological environmental impact assessments in the KAERI, backfitting the operation system of waste-related facilities, strengthening supervision of the safety management department, conducting a safety culture assessment by an outside agency, and etc., and report them to the next NSSC commissioners’ meeting.

In addition, the NSSC plans to seek its policy improvement in a way that strengthen its regulatory responsibilities for the safety of nuclear fuel cycle facilities such as doubling the number of periodic inspections of nuclear fuel cycle facilities, including natural evaporation facilities, and establishing a team dedicated to conducting on-site inspections of the KAERI at any time.

「Definite Change, 2020 Korea」 Realize Nuclear Safety For People to Be Safe and Relieved 

 - 2020 Strategic Plan of the Nuclear Safety and Security Commission -

<Directions for 2020 policies>

◈The NSSC will strengthen preemptive responses, eliminate blind spots, accelerate innovation and communication, and expand collaboration systems.

[1] To strengthen safety management of nuclear power plants, a comprehensive safety level will be quantitatively evaluated, and an inspection system that applies inspection items and methods differentiated according to the safety level will be developed.

※Complete the conformity review of the Preliminary Decommissioning Plan for all nuclear power plants, including Kori Unit 1 ( by the end of 2020)

[2] In order to preemptively guard against radioactive accidents in neighboring countries such as China and Japan, the surveillance network will be expanded * to be more dense and the Joint Emergency Drill among Korea, China and Japan will be conducted.

* (China) Install additional monitors at 23 locations in the western and southern regions and 2 locations in the Korea-China joint waters

  (Japan) Increase the number of locations where tritium analysis is conducted (22 → 32 locations) and the frequency of monitoring at the main inflow points (once a year → 4 times a year)

[3] In order to respond to disasters with the highest priority on the protection of residents, the response system will be restructured into a joint response system led by the NSSC and the Ministry of the Interior and Safety. The number of emergency medical institutions will be increased (24 → 31).

[4] In order to resolve the blind spots in radiation safety management, such as radiation in our living environment, the NSSC will revise safety standards for each field and standardize measurement methods through collaboration with other ministries.

[5] The NSSC will strengthen the protection * for radiation workers in order to eliminate the blind spots in safety management of radiation users subject to reporting (approximately 7,200 institutions).

* Develop tailored training programs and enhance the inspection and check-up of radiation equipment

[6] The NSSC will nurture safety regulation experts by opening and operating nuclear safety regulation courses at universities*.

* Nuclear safety regulation courses will be opened at four universities selected through public offering in 2020

[7] The NSSC will form and run the Public Consultation Group to gather opinions and strengthen communication throughout the entire process from establishment to implementation of nuclear safety policies.

On March 19th, the Nuclear Safety and Security Commission (Chairperson Uhm Jaesik, hereinafter referred to as the "NSSC") announced the 2020 strategic plan, which contains five key tasks to be carried out in 2020.

In order to achieve the vision of “Nuclear Safety for People to Be Safe and Relieved,”, the NSSC presented five key tasks in the 2020 strategic plan:

① Preemptively strengthening safety management of nuclear facilities;② Establishing a radiation safety system without blind spots;③ Strengthening capacity to respond to large-scale accidents and disasters;④ Laying out a strong foundation for safety regulation; and⑤ Communicating with empathy and spreading autonomous safety culture.

Chairperson Uhm Jaesik emphasized, “In 2020, the NSSC will put the highest priority on resolving the blind spots in nuclear and radiation safety management, and through cooperation with related ministries the NSSC will make definite changes that people can feel.”

[1] Preemptively strengthening safety management of nuclear facilities

① The NSSC will develop an inspection system (by 2022) to quantitatively evaluate the overall safety level by revising the current regulatory policies that are focused on performance inspections of individual safety facilities.

- The NSSC will introduce an inspection system that differentiates periodic inspection items and methods according to the evaluated overall safety level of each nuclear power plant

※ (Overseas Cases) Other countries including the United States and Japan utilize the probabilistic safety assessment (PSA) to quantify and classify safety management levels of each nuclear power plant and conduct differentiated inspections based on the evaluated level.

To this end, the NSSC will design the basic concept of a safety management system suitable for domestic nuclear power plants, and develop a safety level evaluation system for each nuclear power plant (by December 2020)

② In preparation for receiving the Final Decommissioning Plan for Kori Unit 1, which is expected to be the first to be decommissioned in Korea, the NSSC will prepare and revise detailed guidelines for safety review.

※ Complete review (by the end of 2020) on the conformity of the Preliminary Decommissioning Plan for all nuclear facilities submitted by the licensee (in July 2018)

- In addition, the NSSC will prepare reasonable safety regulations for exemption and recycling of wastes that have comparably less radiation effects in preparation for the full-scale decommissioning of the nuclear power plant.

※ Introduce a system to separate construction permits and operation licenses for high-level waste disposal facilities

③ The NSSC will build a drone detection and blocking system in stages to actively react to illegal drones flying near the nuclear power plants.

* 'High-performance surveillance cameras will be installed by the first half of 2020 (by the Korea Hydro and Nuclear Power) to strengthen anti-aircraft surveillance. By the end of 2020, tests and verification of detection and neutralization equipment such as radar and radio wave blocking equipment will be pursued.

[2] Establishing a radiation safety system without blind spots

① The NSSC will establish a pan-government cooperative system* in the field of radiation safety management to coordinate the work among ministries and collaborate together so that the blind spots in safety management can be resolved.

* Make the Nuclear Safety Policy Consultation more active and establish the Radiation Safety Policy Working-level Consultation

- In consideration of conformity with international standards, the NSSC will support the revision of safety standards, measurement methods, etc. that are handled and developed by each ministry.

② To monitor radiation for imported cargo, additional radiation portal monitors(RPM) will be installed at airports and ports (128 units in 2019 → 134 units in 2020), and the NSSC will strengthen joint inspections with the Korea Customs Service.

③ For radiation users subject to reporting (approximately 7,200 institutes)that may have been laid in the blind spot of safety management, the NSSC will strengthen the protection of workers by providing customized safety training and inspecting radiation equipment.

④The NSSC will establish a plan to mutually share the exposure records of radiation workers that are currently managed by each ministry, and in cooperation with the Ministry of Land, Infrastructure and Maritime Affairs, the NSSC will strengthen the safety management* of space radiation for aircraft crew members.

* Ensure trustability of the program to assess dose from cosmic radiation and extend the dose record retention period (currently 5 years)

[3] Strengthening capacity of responding to large-scale accidents and disasters

① In preparation for radioactive accidents in neighboring countries such as China and Japan, the NSSC will monitor radiation levels with related ministries and work with the international community in order to systematically respond to such accidents.

- In preparation for radioactive accidents in neighboring countries, the NSSC will strategically expand the radiation monitoring network (171 stations as of 2019) that is concentrated around the domestic nuclear power plants

* (China) Install additional monitors at 23 locations in the western and southern regions and 2 locations in the Korea-China joint waters

  (Japan) Increase the number of locations where tritium analysis is conducted (22 → 32 locations) and the frequency of monitoring at the main inflow points (once a year → 4 times a year)

- The NSSC will hold the Joint Emergency Drill among Korea, China, and Japan (in the second half of 2020) to quickly share emergency information between neighboring countries. The result and outcome of the drill will be intensively reviewed in the Top Regulators' Meeting among Korea, China and Japan (expected to be held in November 2020).

② The NSSC will reform the government's response system* so that the Ministry of the Interior and Safety can comprehensively oversee and support and protect residents in the event of a large-scale radioactive disaster.

* National Emergency Management Committee (chaired by the Prime Minister) will be led together by the chairman of the NSSC and the minister of the Ministry of the Interior and Safety as co-executive secretaries.

- The number of radiation emergency medical institutions will be also increased(24 → 31)for rapid medical response in the event of a disaster.

③ The NSSC will thoroughly verify the Accident Management Program against severe nuclear accidents such as the Fukushima accident, and prepare a government-wide accident recovery strategy (by December 2020).

[4] Laying out a strong foundation for safety regulation

①The NSSC will open safety regulation courses* such as nuclear safety legislation and procedures by supporting operating expenses and education programs at universities, and through this program, the NSSC will nurture safety regulation experts.

* Nuclear Safety Regulation Courses will be opened at 4 universities selected through public offering in 2020.

② The NSSC will increase the support for research for discovering new regulatory demands in various fields by professional experts in universities and the industry.

* (2019) 1.5 billion KRW for 7 projects→ (2020)4.85 billion KRW for more or less than 30 projects (4.6 times compared to the previous year)

[5] Communicating with empathy and spreading autonomous safety culture

① The NSSC will form and run the 「Public Consultation Group」 and thus pursue communication with a wide range of the public from the initial stages of policy establishment such as the Comprehensive Nuclear Safety Plan.

-The Public Consultation Group will consist of students, the general public, and experts from all walks of life (in September 2020) to conduct a faithful demand survey on the safety policies that the public wants.

②A special inspection (by a third party) to identify safety vulnerable elements*at each nuclear power plant (in July 2020) will be conducted, and based on the result, a safety culture improvement plan will be established for the KHNP (December 2020).

* Irrational organization culture and work environment, internal regulations and procedures that hinder safety, and etc.

- The NSSC will ensure the implementation of the plan by holding official meetings between the NSSC and the KHNP (in the first half of 2020)

③ During the review process of the Accident Management Program, the NSSC will promote transparent disclosure of the information such as documents related to questions and answers between a Technical Support Organization(the Korea Institute of Nuclear Safety) and the licensee.

-In addition, the NSSC will establish a nuclear safety information center in cooperation with local governments in order to improve the accessibility to information for local residents living around the nuclear power plant.

※Prepare an operation plan for the nuclear safety information center (in the later half of 2020) and start full-scale operation (in 2021)

That NSSC Secretary General received Red-stripe Order of Service Merit Is Not Related to Result of Voting for Modification of Operation License of Wolsong Unit 1

On March 13th, Chosun Ilbo published an article titled, “the NSSC that Voted for Abolishment of Nuclear Power Plants: Presidential Merit Awarded to the Public Officer Who Took the Lead,” and claimed that Jang Bohyon, Secretary General of the NSSC, was awarded with a Red-stripe Order of Service Merit for playing a leading role in the decision to shut down the Wolsong Unit 1 earlier than its license expiration. The news media also argued that considering the fact that the Board of Audit and Inspection(BAI) is currently looking into the issue of the shutdown of the Wolsong Unit 1, it is inappropriate to reward the high-ranking official involved in the issue.

About the news article, the NSSC explains:

The Order of Service Merit awarded to Secretary General Jang Bohyon is for public officials who have served more than 15 years and according to Article 14 (Order of Merit) of the Award and Decorations Act, it is given to those who have distinguished themselves by working diligently and making remarkable achievements during the tenure. Rewards for outstanding public officials (order of merit) are regular awards that are awarded annually according to the government awards guidelines.

According to the guidelines, those who are under investigation, accused or convicted of a criminal charge will be restricted from recommendation, but an audit on a specific issue is not counted as a reason for restriction.

On the other hand, the audit of the BAI is focused on how economic feasibility of the Wolsong Unit 1 was assessed by the Korea Hydro and Nuclear Power. The

modification of the operation license for permanent shutdown, permitted by the NSSC, was reviewed in the view of whether safety is technically assured, not whether it is economically feasible.

The time of recommendation was December 13th, 2019, before the voting to modify the operation license of Wolsong Unit 1 took place. The decision to shut down the

Wolsong Unit 1 is not related, in the perspective of timing, to the award of the Order of Service Merit unlike the media(Chosun Ilbo) claims.

In addition, there is no content related to Wolsong Unit 1 in the recommendation for awards which is considered at the time of awardee review.

Regarding Concrete Voids of Containment Buildings of Hanbit Unit 3 and 4, the NSSC Will Verify Structural Integrity Objectively and Transparently

On March 12th, Hangyere released an article titled “9 years since Fukushima accident – Environmentalists Call For Phasing Out Nuclear Energy.” The article

quoted Honam Joint Action as saying: “The NSSC and the KINS do not admit the danger of nuclear power plants and think the plants are safe if repaired,” and, “the

Hanbit Unit 3 and 4 have been in the state of shutdown since May 11th, 2018 and May 17th, 2018 , respectively, due to concrete voids.”

Regarding the article, the NSSC explains:

The NSSC is an independent regulatory authority and strictly regulates the Korea Hydro and Nuclear Power(KHNP), the licensee, on its safety management in

accordance with the laws. The NSSC closely checks regulatory safety requirements for nuclear power plants and approves resumption of the power plant operation

only when it confirms all relevant requirements are met.

Particularly for the concrete voids found in the containment building of the Hanbit Unit 3 and 4, the KHNP is carrying out structural integrity assessments.

When the KHNP submits the assessment result to the NSSC, it will verify the result and safety of the units in an objective and transparent manner through technical

review of the KINS, a technical support organization, and independent verification of the Korea Concrete Institute.

The NSSC Is Investigating Leakage of Waste Under Clearance Level at Taekwang Industry

-Up to now, there has been no radiological impact on the environment. -

On February 19th, the Nuclear Safety and Security Commission (Chairperson, Uhm Jaesik, hereinafter referred to as the “NSSC”) received a report* from Taekwang Industry that liquid waste had leaked during the collection of samples from the storage tanks (approximately 96.5 tons) for analysis in preparation for the disposal of radioactive wastes, which are subject to the self-disposal as they are below the clearance level**. Upon receiving the report, the NSSC immediately dispatched a team of experts from the Korea Institute of Nuclear Safety (President Son Jae-young) to the site for detailed investigation.

* On the February 19th, about 2 tons of liquid leaked from the tank through its doorway while a worker was collecting the sludge-type waste stored in the tank. Of the 2 tons, 0.5 tons of the waste has been retrieved.

** The estimated annual dose is so low, less than 10 μSv (the allowable annual dose is 1,000 μSv for the general public), that this type of wastes can be disposed as general waste.

To date, the investigation team has assessed the radiological impact on workplaces, liquid wastes, nearby drainage pipes, and rivers and judged that the environment has not been affected.

※ Waste which was to be disposed of: Waste for which depleted uranium was used as a catalyst during the production of acronitrile. Depleted uranium has a lower level of radiation compared to natural uranium.

Pollution was not detected with pollution detectors that measured the areas surrounding the wastes and tank. The radiation dose rate was also found in the natural range of 0.1 to 0.2 μSv/h.

As a result of analyzing the radioactive concentration of the liquid waste, collected by Taekwang Industry at the time of leakage, it was 0.046 Bq/ml, which was much lower than the exempt clearance level*, set by the International Atomic Energy Agency (IAEA), 1 Bq/g.

* IAEA Safety Guide RS-G-1.7 (Application of the Concepts of Exclusion, Exceptional and Clearance) 

As a result of evaluating the samples from drainage pipes and stream near the workplace, it was found that the level was 4.0 × 10-6 Bq/mL, which is not different from the uranium concentration levels measured in domestic rivers or seawaters.

The NSSC is in the process of acquiring additional samples for more accurate assessment. The NSSC will thoroughly investigate the matters related to the company’s radioactive waste management based on CCTV recordings, various records, and interviews with relevant staffs and make the result of the investigation available to the public to ensure that similar events do not recur.