Text

Revised Response to RAI 1-g
	ML22293A431
Person / Time
Site:	Zion File:ZionSolutions icon.png
Issue date:	10/17/2022
From:	; ZionSolutions
To:	; Office of Nuclear Material Safety and Safeguards
References
	ZS-2022-044
	Download: ML22293A431 (25)
	v • d • e

ZionSolutions ZS-2020-044 Zion Nuclear Power Station, Units 1 and 2 Revised Response to RAI 1-g

NRC RAI-lg:

Given the observations in the survey units listed above, as well as any additional observations resulting from ongoing licensee activities under the Final Status Survey Due Diligence Plan, provide an explanation for why the licensee surveys are adequate.

ZIONSOLUTJONS REVISED RESPONSE:

ZionSolutions has revised its response to RAI-J g in response to comments received from NRC staff. We believe that this revised response addresses the issues raised by NRC, in particular the inclusion of survey units to ensure that the power block are and CCDD haul path are included in the DRP Survey Plan.

The licensee surveys were conducted following the process for performing FSS in accordance with the LTP, MARS SIM 1, and other regulatory guidance documents. As such, ZionSolutions believes that the surveys were conducted in accordance with best industry practice. The licensee surveys were designed to find uniformly distributed contamination and were adequate and successful for that purpose.

Particles are a source term, and it is ZionSolutions' intention to not leave any particles in site soil that present an unacceptably high risk. ZionSolutions accomplished this by performing a 100%

surface area scan in the 41 survey units that are within the scope of the DRP Survey Plan using DQOs and survey methods that have been specifically designed to have sufficient sensitivity for the detection of particles. 2 Evaluation Criteria. In order to determine the scope of the DRP Survey Plan, ZionSolutions developed evaluation criteria to identify those survey units with the potential to contain DRPs.

These criteria were developed based on experience conducting other surveys at the site. They also were informed by consideration of the transport mechanisms discussed in response to RAi-l c. The following criteria were identified and applied to determine which survey units to include in the DRP Survey Plan. Included are survey units:

where clean concrete demolition debris (CCDD) was temporarily staged after completion ofFSS along the travel path for CCDD to loadout area (also sometimes referred to as the "haul path")

where waste loadout areas resided 1 "Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM)," NUREG-1575, Revision I, U.S.

Nuclear Regulatory Commission, August 2000.

2 See Connecticut Yankee Atomic Power Co., 58 N.R.C. 262, 297-299 (2003) (finding that Connecticut Yankee's compliance with MARSSIM provides a sufficient plan for detecting hot particles in its LTP, with a separate opinion noting that a licensee cannot implement a detection plan until the final site survey results are available).

1

with areas of elevated activity identified by ORJSE during the April 2021 inspection survey Class 2 survey units that were adjacent to Class 1 survey units where particles or elevated areas had been previously identified DRPs,vere previously identified and the SU was not surveyed by ORJSE specifically for DRPs or surveyed using the DRP DQOs The final criterion was added subsequent to the initial development and execution of the DRP Survey Plan. Including all survey units where a DRP was identified results in the addition of eight survey units: 10202B, 10202D, 10207A, 10220A, 10220G, 12201D, 12201E, and 12204A.

Exclusion Criteria. ZionSolutions also developed exclusion criteria for assessing survey units that were not identified for inclusion in the DRP Survey Plan. The application of these criteria is intended to give a high level of confidence that the site has been adequately surveyed and that ZionSdlutions and the NRC have a high level of confidence that any activity below the MDA remaining at the site is not significant.

None of the exclusion criteria is intended to apply in stand-alone fashion, although that is typically the case in the application of exclusion criteria. Rather, they are taken together to provide additional justification for excluding survey units from further consideration. For example, completion of FSS and finding no DRPs is one of the exclusion criteria. While FSS alone is not considered adequate in and of itself to identify DRPs, it is important to recognize that 19 DRPs were detected during FSS. As such, it provides useful data regarding the likelihood of unidentified DRPs remaining in any given survey unit.

One criterion that was considered but not included was all Class l survey units. The designation of a survey unit as Class 1 is based upon an area having the greatest potential for exceeding DCGLs, which are based on distributed contamination. There is no basis for assuming that Class 1 areas are more likely to contain DRPs. As such, there is no compelling basis for including all Class 1 survey units in the DRP Survey Plan.

The exclusion criteria for survey units not included in the DRP Survey Plan include a combination of the following:

For Class 3 survey units, ZionSolutions assessment of the source and transport of the DRPs that have been identified did not give any indication that the survey unit would contain DRPs.

DRPs were not detected in prior surveys.

FSS was performed in the survey unit with no identification of DRPs.

ORJSE performed an independent verification survey in the survey unit, prior to 2021, with no identification of DRPs.

2

ORISE did not detect DRPs in its April 2021 surveys designed to identify DRPs.

Surveys performed during final site grading did not identify DRPs.

CCDD staged or transported through prior to the completion of FSS.

ZionSolutions has prepared Table lg-J, which indicates how each individual survey unit compared with the criteria for inclusion or exclusion in the DRP Survey Plan. Also attached is Figure lg-1, which illustrates all survey units and identifies whether each was:

Surveyed by ORJSE specifically for DRPs Surveyed by Z ionSolutions using DRP DQOs Contained a DRP that was identified at any point since 20 J 4.

The survey units included in the ORJSE surveys for DRPs were not surveys of the entire survey unit; rather they were partial surveys. ZionSolutions' believes that these surveys provided valuable information and, thus, are valid for inclusion.

ZionSolutions' response to RAI-1 g was the subject of lengthy discussion during the regulatory audit conducted July 19-20, 2022, and August 24-25, 2022. The following information regarding the justification for inclusion or exclusion of survey units from the DRP Survey Plan is provided in response to questions raised by NRC staff during the audit.

3

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Provide additional information regarding the basis for including survey units in the DRP Survey Plan.

Inclusion in previous surveys. The fo llowing are descriptions of the surveys that ZionSolutions has relied upon, cumulatively in most cases, to determine if a survey unit met the criteria for inclusion or exclusion from the DRP Survey Plan. While the surveys described below were not all performed using DRP data quality objectives (DQOs) (it is stated in each description below when they were performed with DRP DQOs), they provide data that is useful for determining if a survey unit is likely to contain undetected particles. As ZionSolutions has demonstrated, any survey technique (slow scan or standard scan speed) would detect DRPs with significant activity.

They also all have been shown to be useful for detecting non-significant particles.

Considering the cumulative, multi-layered nature of these surveys, ZionSolutions believes that past surveys are valid criteria for selecting or not selecting specific urvey units for the DRP Survey Plan, regardless of DRP-specific DQOs.

Power Block Radiological Assessment A radiological assessment (RA) was performed in the power block area from April 18, 2019, to May 28, 2019. The purpose of the RA was to assess the areas affected by the removal of the sacrificial layer for DRPs. 100% of the fo llowing survey units were scanned for DRPs:

Table lg Power Block RA Survey Units 10203A 12106 12110 12201C 12202D 10203F 12107 12111 12202A 12202E 12104 12108 12201A 12202B 12202F 12105 12109 12201B 12202C The power block RA employed a 0.25 mis scan speed, which is equivalent to the scan speed included as the primary scanning DQO in the DRP Survey Plan. As such, ZionSolutions bel ieves that the Power Block RAs provide useful data for identifying DRPs and can be relied upon, in combination, with other surveys. Six DRPs were identified and remediated in survey units 12107, 12109, 12110, 12201B, and 12201C during the power block RA.

Travel path for CCDD to load out area (also referred to as the "haul path)

The survey units along the travel path were included in the DRP Survey Plan. There has been some confusion on this point, but ZionSolutions wishes to be clear that these survey units have been surveyed for DRPs. The path for transferring the CCDD from the survey units where it was staged (12205A-E) and the path along which it was transported are shown below in figure dated June 16, 2021.

13

Date for Affected and Immediately Adjacent Survey Units Figure lg-2

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9/9/2019 10:zoeD l l/l/2019 12202C 9/ 10/2019 10l06C llYll/2019 1(1!011) 10/17/2019 102">0 ll/ll/2019 10207' 10/21/2019 10:ZO,C ll/ll/2019 122021!

10/l/2019 10J:l4ll ll/7/2019 06-16-21 14

Final Site Grading and Seeding Surveillances Final site grading and seeding commenced on August 31, 2020, and was completed September 23, 2020. During this time and after its completion, surveillance surveys were performed in accordance with ZS-LT-300-001 -003, "I olation and Control for Final Status Survey," to assess if radiological condition differed in the urvey units affected by final site grading and seeding from the radiological conditions reported for fina l Latus urvey (FSS).

The scan coverage during these surveillances varied depending on the activity performed during final site grading and seeding. A 100% gamma scan was performed on areas affected by digging, such as where swales were being created or where soi l was being borrowed to build up a different area. urvey units in which a po1tion of the survey unit was affected by swales or borrow areas are as fo llow :

Table lg Final Site Grading and Seeding Surveillance Survey Units Affected by Digging 10201A 10203B 10206A 10207B 10208C 10221A 12110 10201B 102030 102068 10207C 102080 10221B 12202A 10201C 10204A 10206C 102070 10209A 10221C 12202B 10202B 10204B 102060 10207E 10209B 102210 12202C 10202C 10204C 10206E 10208A 10209C 12108 122020 10203A l 02040 10207A 10208B 102090 12109 12202E Additional scans, typically at a 5% coverage, were performed on soil areas that were scarified for seeding purpose and build-up areas. Thi type of survey was performed for approximately 80%

of the Class 1 survey units in which seeding was necessary.

The final site grading and seeding surveillances employed the 0.25 m/s scan speed, which is the DQO for DRP scanning.

Documentation for the final site grading and seeding surveillances is limited to statements of positive or negative identification of elevated areas of activity that would differ from the radiological status of survey units during FSS. Thus, ZionSolutions cannot provide detailed scan or ample data for the surveys performed. No particles were identified in these surveys.

ORI_SE April/July 2019 lndependent Verification Surveys The Oak Ridge Institute for Science and Education (ORlSE) performed independent verification (IV) surveys in April and July of 2019. The survey units included in these surveys are the same as in Table 1.

In April, two DRP were identified in survey unit 12106. Later, in July, after the power block RA was performed by the licensee, two additional particles were found in survey units 12202D and 12202F. 12106 was not included in the DRP survey plan, while 12202D and 12202F were.

According to 5271 -SR-07-0, "Independent Confirmatory Survey Summary and Results for the Subsurface Soils Associated with the Sacrificial Barrier at the Zion Nuclear Power Station Zion, Illinois," the scan survey performed was of "medium-to high-density coverage" while "passing 15

the detector slowly over tbe surface." The scanning speed for the April/July 2019 JV surveys is not documented and tbe purpose of the surveys was not expressly to identify DRPs, but ratber to identify potential subsurface contamination after the removal of the sa*crificial layer.

Nonetheless, the scan surveys performed by ORJSE were sensitive enough to detect any DRPs of significance and are considered as valid data points to inform the decision of whether to include specific survey units in the DRP Survey Plan.

ORISE December 2019 I January 2020 FSS Confirmatory Surveys ORJSE performed FSS confirmatory surveys in December 2019 and January 2020. The survey units included in these surveys are as follows:

Table lg ORISE FSS Confirmatory Survey Units 12102 10202D 10208A 1021 IA 10214E 10220]

12203D 12103 10203A 10208B l0211B 10214F 10221A 12204A 12112 10203D 10208C 10213A 10219A 102218 12204B 12113 10206D 10208D 10213B 10220A 10221C 12204C 10201A 10206E 10209A 10213C 10220E 10221D 12205A 10201B 10207A 10209B 10214A 10220F 12201D 12205B 1020 IC 10207B 10209C 10214B 10220G 12203A 12205C 10201D 10207D 10209D 10214C 10220H 12203B 12205D 10202B 10207E 10209E 10214D 102201 12203C 12205E According to 5271-SR-08-0, "Independent Confirmatory Survey Summary and Results for the Remaining Land Areas at the Zion Nuclear Power Station Zion, Illinois," the scan survey performed was of "medium-to high-density coverage" while "passing the detector slowly over the surface." As with the previous surveys performed by ORJSE in 2019, it is not documented at what specific speed the scanning was performed at for tbe December 2019/January 2020 FSS confirmatory surveys and the purpose of the surveys was not expressly to identify DRPs. The scan surveys performed by ORISE were sensitive enough to detect any DRPs of significance and are considered as valid data points to inform the decision of whether to include specific survey units in the DRP Survey Plan.

One DRP was identified in survey unit 12204A during the ORISE FSS confirmatory surveys.

Survey unit 12204A was included in the DRP Survey Plan.

16

ORJSE April 2021 Inspection Survey ORJSE performed an inspection survey in April 2021 to assess remaining residual radioactivity and DRPs at the site. The survey units included in the survey are as follows:

Table lg ORISE April 2021 Inspection Survey Units 10205 12112

!0206B I0208C 10209£ 10214C 10221A 12203B 10222 12113 10206C 102080 1021 2A 102140 102218 12203C 10223 10204A l0207B 10209A

!0212B 10214E 10221C 122030 10224 10204B 10207C 10209B 10213A 10214F 12201A 12104 10204C 10208A 10209C 10214A 10220C 122018 12105 10206A 10208B 102090 10214B 102201 12203A According to 5271-SR-09-0, "Independent Confirmatory Survey Summary and Results Assessing the Presence of Residual Radioactivity and Radioactive Particles within Select Land Areas at the Zion Nuclear Power Station Zion, Illinois," the scan survey performed was based on a presence/absence design that included high-density coverage within systematically-located grids. The report states that the scan speed used was 0.25 m/s, and the detector was held a maximum of 3 inches above the surface. The scan surveys performed by ORJSE were performed with the scan DQO for DRPs and were sensitive enough to detect any DRPs of significance.

Eight DRPs were identified and remediated from survey units 10204B, 10209E, 102201, 12201B, 12203A, and 12203D during the ORJSE April 2021 Inspection Survey. All five of these survey units were included in the DRP Survey Plan.

FSS prior to 2021 FSS performed prior to 2021 (and the implementation of the DRP Survey Plan) did not utilize DRP DQOs. As stated in the response to RAI-lg, the licensee surveys were designed to find uniformly distributed contamination and were adequate and successful for that purpose.

Nonetheless, particles were identified and remediated during the FSS process despite not using DRP DQOs. FSS technicians were trained to slow scan speed while scanning to investigate rises in count rate. This is an effective method that has shown to identify particles on multiple occasions. Additionally, as explained above, no particle identified to date has contained sufficient activity to pose an unacceptably high risk to a future occupant. Furthermore, particles that would potentially pose an unacceptably high risk to a future occupant are particles with activity that would be detected using the normal FSS scan methods.

DRP Cleanup Efforts in 2014 and 2015 ZionSolutions performed scan surveys that targeted affected and potentially affected areas after the incidents in 2014 and 2015 (described in the response to RAI-c). The extent of the DRP contamination events was bounded by scanning in each case. These surveys were not performed using DRP DQOs, but hundreds of DRPs were identified and remediated. Survey units partially scanned during the 2015 cleanup effort are as fol lows:

17

Table lg 2015 DRP Cleanup Effort Survey Units 2104 12109 102030 10221B 12202A 12202F 2105 12110 10203F 10221C 12202B 12203A f-2106 12111 10207E 12201A 12202C 12107 10203A 10208D 12201B 122020 2108 10203C 10221A 12201 12202E urvey areas (survey units are not defined in the documentation for this event) partially scanned during the 20 14 cleanup effort are as fo llows:

Table lg-7 -2014 DRP Cleanup Effort Survey Areas 10202 10208 10203 10209 10204 10221 10206 Physical barriers to vehicular and pedestrian access to the beach area survey units Another factor that affects the opportunity for transport of DRPs from one survey unit to another is the presence of access controls. The I imitations upon vehicular and pedestrian traffic among survey units also was taken into account in the selection of survey units for inclusion in the DRP Survey Plan.

The eastern-most boundary of the former Radiologically Restricted Area (RRA) consists of numerous survey units (1020 1, 12101, 12102, 12103, 12204, 12112, 12203, 10211, and 10221) that abut the beach survey units to the east (10222, l 0223, and l 0224). DRPs have been identified in the past in a few of the eastern-most survey units within the RRA (12204A, 1211 2, and 12203D).

As seen in the photos below, there is a chain-link fence that runs north and south for the entire length of the eastern-most survey units within the RRA. This fence serves as a barrier that prevents vehicular and pedestrian traffic from accessing the beach survey units from the RRA, and vice versa. Any vehicles, equipment, or personnel who wish to access the beach survey units from the RRA would have to first be surveyed out of the RRA.

Additionally, staff expressed concern regarding the potential for DRPs to be transported from SUs 10220A, B, D, E, H, I, and J mto the southern-most SU 10220C. However, a fence 1s present on the north side of SU 10220C that prevents any vehicles, equipment, or personnel from accessing 10220C.

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Figure lg-3 Potential for surface water runoff to transport particles It has been suggested that DRPs may have migrated to impact the beach survey units via surface water flow, i.e., runoff during heavy rains. While this prospect cannot be eliminated completely from consideration, ZionSolutions believes there is a remote potential for the transportation of DRPs via surface water flow. This is due to two factors:

First, since final site grading, the ground cover within the RRA has become thick with native grasses and small trees. This greatly reduces the amount of runoff that was previously identified prior to site grading.

Secondly, as seen in the photos above, there is a silt fence attached to the bottom of the fence for the entire length of the eastern RRA boundary. Another silt fence is located approximately 6 feet to the west of the fence and is present for a good portion of the length of the eastern RRA boundary. These two silt fences serve as a barrier to prevent the potential transportation of DRPs via surface water flow.

Similarly, regarding the potential for DRPs to migrate via surface water flow from SUs 10220A, B, D, E, H, I, and J into the southern-most SU 10220C, this is prevented by the presence of vegetation. As seen in the photo below (standing in 102201 and looking south into 10220C) the area to the north of the fence is covered with extremely dense grasses and trees. The grass and trees have been present throughout decommissioning and runoff during heavy rains was never an issue in this southern portion of the site.

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Figure lg-4 Describe the location of the culvert on the north side of the site and the potential for water transport of DRPs in that area. Include rationale for reclassification of 10212A, B, and C, and 10213B and C to Class 1.

The culvert on the north side of the site borders the southern edge of SUs 10212D and 10213C.

The two photographs below show the ditch in 2016 and 1019.

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Figure lg-5 Drainag Ditch in 10212D in Ma of2016 Drainag Ditch in 10212D in Augu t of2019 21

This area of the site has been subject to flooding due to clogging of the outfall and heavy rains in November 2018 that led to portions of SUs 10212, l 0213, and 10214 being underwater. The flooding resulted in the contamination of portions ofSUs 10212 and 10213 with plant-generated contamination and their subsequent subdivision and reclassification. No DRPs have been discovered in these SUs (10212A, ]0212B, 10212C, 10212D, 10213A, 10213B, and 102l3C).

The flooding and reclassification of these SUs have been described in detail in previous submittals to the NRC. The most thorough description of these events is contained in the answer to RA ls Sa, 56, and Sc in response to the NRC 's RAJ of April 20, 2020. This description of the flooding, along a description of the surveys, sampling, and sampl ing results is contained on pp.

26-36 of Attachment 2 to that RAJ revised response.3 We have included this excerpt from that letter herewith for your convenience. We also have included the supplemental spreadsheet, "Drainage Ditch Flood Timeline," from the February 2021 RAJ responses.

Areas previously identified as being at higher risk In its February 10, 202 1, response to RATs, ZionSolutions stated:

A second high-risk area for the presence of DRPs would have also been in survey units 10221A, l0221B, and 1022 1C, where reactor internals segmentation liners were temporarily stored.

The rationale for not including those areas in the DRP plan is that they were considered to have been adequately surveyed for particles. In 2019, ZionSolutions performed the FSS of 1022 I A through C. The FSS of those surveys included a 100% scan of the soil. One particle was identified in survey l 0221 C during FSS, as indicated on our map. No particles were identified during the FSS of 10221A or 10221B.

ORISE performed an approximately 50% scan survey of survey units 1022 lA through C in 2020 during their FSS confirmatory (the 50% coverage is based on the map provided in the ORISE final report). No particles were identified during those surveys. In 2021, ORISE performed an approximately 15% to 25% scan survey in each of survey units 1022 1 A through C. ORISE did not identify any particles in these areas during the 2021 surveys. Lastly, a swale was dug into the soil in survey units 10221A through D. As part of the surveillance for the grading activities, a I 00% scan survey using DRP DQOs was performed on any area affected by digging. No particles were identified during those surveys.

These multiple surveys provide reasonable assurance that survey units 10221A through C did not need to be included in the DRP Survey Plan as they were no longer high-risk. We feel these areas have been adequately characterized for particles.

3 ZS-2021-0001, G. van oordennen, "Revised Response to Request for Supplemental Information and Request for Additional Information Related to Final Status Survey Final Reports," February 10, 2021.

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Please describe the statistical analysis, the Binomial Test, Zion Solutions prepared to justify the thoroughness of its selection of survey units for inclusion in DRP Survey Plan.

ZionSolutions has performed a nonparametric statistical test called the Binomial test in order to determine if there is some statistically significant proportion of survey units in which we could say particles are li kely to exist. This enabled us to compare that significant proportion to the proportion of survey units that were surveyed using DRP data quality objectives (DQOs) to determine if the survey coverage is reasonable.

We start with the null and alternative hypotheses. The null hypothesis states that the population proportion is equal to 0.3, or that it is expected that 30% of the survey units contain particles.

The alternative hypothesis states that the population proportion is less than 0.3, or that less than 30% of all survey units contain particles.

Then we look at our data. Our sample is the 52 survey units that have been surveyed since the April 2021 inspection survey using DRP DQOs. This number of survey units equates to 45% of all of the site's open land survey units. That is an important proportion to keep in mind; we have surveyed nearly half of all land survey units for DRPs. That does not take into account any radiological assessments or any surveillances performed with DRP DQOs prior to or after the April 2021 inspection survey (including, e.g., final site grading, isolation and control surveillances, or power block radiological assessment). A ll of the survey units included in the test, shown in the figure below, were completely (100%) surveyed by ZionSolutions.

Within our sample of 52 survey units, particles have been identified in 9 survey units. For the purpose of the Binomial test, a survey unit containing a particle is considered a "success."

The following is the output of the Binomial test function in the program R using 9 successes out of 52 trials, a proportion of 0.3, and the indication of which alternative hypothesis is being used

(" less" = less than the stated proportion of 0.3).

Figure lg-6

> bino.test(9,52,.3,alternative*"less")

Exact binomial test data:

9 and 52 number of successes* 9, number of trials* 52, p-value

0.02803 alternative hypothesis: true probability of success is less than 0.3 95 percent confidence interval:

0.0000000 0.2825948 sample estimates:

probability ot success 0.1730769 The conclusion of the Binomial test is that the null hypothesis is rejected based on the p-value of 0.028 being less than the significance level of 0.05. (The p-value is the probability of observing a 23

result at least as extreme as the result actually observed.) Rejecting the null hypothesis indicates that the proportion of survey units that contain particles is less than 0.3, or less than 30% of all survey units contain particles. R also provides a confidence interva l. We are 95% confident that the true proportion of survey units that contains particles is between O and 0.28; and we can see that our proportion of "success" in this case was equal to 0. 17 (9 out of 52 survey units).

Given that ZionSolutions has surveyed approximately 45% of all open land survey units for particles and it is expected that less than 30% of the survey units would contain particles, the survey coverage i reasonable.

One additional facto r to consider in the use of this test i that the Binomial test assumes the sample is random. But given that the actual sample was biased, that is, the survey units included were selected based upon the presumption that they were most likely to contain particles, the results of this binomial test are highly conservative. It is likely that the true, statistically-significant proportion of survey units containing particles is much less than 0.3, given that the survey units were selected for assessment based on their potential to contain a particle and not selected at random.

ZionSolutions believes that even if we were to survey more survey units and locate additional particles, which is possible (the probability is not 0), our knowledge regarding the origin and activity of particles indicates that those particles would be of insuffi cient activity to pose an unreasonable risk to a future occupant. Thi view is supported by the fact that no particle identified to date has been a "particle of significance," in other words, a particle with activity that would present an unreasonable risk to a future occupant, based on our risk analysis. We believe that this provides NRC with the information it needs to make a findin g of reasonable assurance that the license can be safely terminated.

We do not believe there is any reason to expect that the distribution in additional areas is greater than what is represented in the Binomial test or greater than the suspect areas that Z ionSolutions already has surveyed. Z ionSolutions proposes that there is no reason to believe that additional survey units would be more likely to contain DRPs. Rather, we believe that the potential for them to contain DRPs is less because additional survey units did not meet the criteria for inclusion in the DRP Survey Plan.

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Figure lg-7 25 Survey Units Surveyed wtth DRP OQOs (since April 2021 )- 133339 m2

..-==-

lJONSoU/TIO'fS Date: 06/1712022

ML22293A431

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