ML19093A129
| ML19093A129 | |
| Person / Time | |
|---|---|
| Site: | Consolidated Interim Storage Facility |
| Issue date: | 04/01/2019 |
| From: | Consolidated Interim Storage Facility |
| To: | Office of Nuclear Material Safety and Safeguards |
| Shared Package | |
| ML19093A183 | List: |
| References | |
| E-53940 | |
| Download: ML19093A129 (11) | |
Text
Enclosure 2 Draft Response to RAI NP-2.4-x with SAR Markups
RAls and Responses Enclosure X to E-XXXX RAI NP-2.4-1:
Provide technical justification for the rating curve of the large playa next to the WCS CISF storage area. This may include the outflow area cross section, the equation and ~a a eters used to calculate the curve, and the details of the calculations under all surfacewat. r flow scenarios.
This information is needed to determine compliance with 1 Response to RAI NP-2.4-1:
0 = CLH 1*5 o er the weir; C = dimensional discharge coefficient; for a broad crested i width; and H = difference between the weir crest elevation and water the reservoir.
Page 6 of 119
RAls and Responses Enclosure X to E-XXXX The flood calculation package of the CISF drainage area dated December 16, 2016, provides calculations and design data that are utilized as input data for the HEC-HMS program. The HEC-HMS non-level dam top routine using the broad crested weir equation and cross-section data internally generates a rating curve for outflow from the large playa and pairs it ith the elevation-storage data to predict the peak storage, elevation, and discharge. The width and the difference between the weir crest elevation and water surface el reservoir is calculated within the HEC-HMS program using the eight station provided in Appendix C, page APP C-12, (weir width and elevation) and t data in Appendix D, page APP C-9 (water surface elevation in the play Two extraneous paired data functions the model input. Neither the elevation-1 nor the inflow-diversion component name therefore, do not affect the model results/a change to the model output or the conclusi CISF drainage area dat er 16, 201 Chapter 2 has been r ve the ext
References:
- 1.
folder on the CD used for all segmen1s as a basin parameter nder the playa reservoir paired data folder of Road Rating Curve" any o e Basin Models and, n be deleted with no n the flo alculation package of the ment B, Flood Plain Report, to SAR us data from Appendix E.
my Corps of Engineers, Hydrological
. 0, December 2013.
apter 2 has been revised as described in the response.
e 5 for Attachment B to SAR Chapter 2 Page 7 of 119
RAls and Responses Enclosure X to E-XXXX RAI NP-2.4-2:
Provide additional information on the erodibility and long-term erosion of the diversi under normal and extreme precipitation events, through all phases of the propos facility. Estimate the seepage through and underneath the berms and the impa the berms' stability through all phases of the proposed facility.
In WCS CISF SAR Section 2.4.2.2, ISP stated that flood events are mo the collection ditch and diversion berms to provide the greatest poss*
to the playa that serves as a water detention pond and potentially the playa. ISP stated that the ditch and berm are to be constru run-on of storm water by diverting it around the operational s compromise of the collection ditch and diversion berms u~
in increased flow across the storage area during some that this increase of flow would be short term and te build-up of water and sediment behind the berm can higher than those modeled without the berm in the even staff requires additional information to evaluate the likeliho overtopping, breach of berm structure, and short-and long-te the integrity of the system, structure an anent in the stora staff requires the estimates of seepage nderneath th seepage to the berms' stability through o osed C potential impact of subsurface water to th AR Figure 2-26, a stormwater collection the WCS CISF storage area.
will be constructed of on-site available mored with o -
e available caliche in order to minimize erosion tion of the berms and ditches will occur during the first phase of the ditches will not be needed for later phases. Inspection of the sediment buildup will be part of the ongoing routine inspection hases. The area between the berms and the storage pads pected rosion, especially after a rainfall. Areas of the site impacted 1 buildup will be repaired to original grades. Inspection and fter normal and extreme precipitation events and through all phases of ge through or under the berms would occur due to the materials used to and to the routine inspections and maintenance performed on all areas storage pads. The berms and ditches are for diverting stormwater around the operationa rage area and any water behind the berm is temporary; therefore, seepage should not impact the stability of the berms. If any seepage were to occur through the berms, subsurface water would have to flow horizontally approximately 470 feet to reach the nearest storage pad, which is not possible due to the sub strata of the site.
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RAls and Responses Enclosure X to E-XXXX The drainage area up-gradient of the collection ditch and diversion berms is characterized predominantly by sand dunes with no clear drainage pathways visible on topographic maps of the area. The soils in this area are classified as hydrologic group A/B, which means the soils have high infiltration and transmission rates as shown on Attachment B, Flood Plain
- eport, Figure No. 2.2.1-1, Soils Boundary Map of the SAR. Stormwater runoff from thes d dunes is highly unlikely; therefore, the potential of a flood water wave occurring behin extremely low.
The maximum berm height will be 2.6 feet. The site will be graded so flows off and around the storage pads. Assuming the berm were to Probable Maximum Precipitation discharge reached a storage pa (P se 8), thee depth of flow on the ground surface is approximately 3 inches.
ddendum A oft Plain Report for calculations, methodologies, assumptions, figure for this worst-scenario. As the flow from the worst-case berm breach m outheastward, the depth o water continues to diminish as it spreads out, thus furth gating any ssibility of flooding the storage pads.
SAR Chapter 2, regarding the be potential ber Impact:
n regarding the berms, as been updated to include information intenance, and calculations regarding the Attachment B to SAR Chapter 2, is included with the response Page 9 of 119
WCS Consolidated Interim Storage Facility Safety Analysis Report Revision 3 Interim The WCS CISF Drainage Evaluation and Floodplain Analysis (Attachment B) models the 100-year flood, the 500-year flood and the PMF to evaluate the effects on the WCS CISF.
The only analysis of significance from a flooding standpoint is the wat playa area resulting from the PMP event. The result is that the WC area is above the maximum water level elevation resulting from demonstrated in Attachment B. The area west of the WCS CI does not result in any ponded water to create a flood area n As noted previously, a stormwater collection ditch an gradient from the WCS CISF storage area. The dit as a matter of operational convenience to mini during precipitation events by diverting it aro 2-26 (CJI Drawing C-1) show the location 2-27 through Figure 2-30 (CJI Drawings C-,
profile of the collection ditch and berm. Berms area will be constructed of on-site available red be on-site available caliche in ord seepage through or under th the berms and to the routine i upgradient of the storage pads.
the area, which will result in sho on the storage area during some p vents.
storage area result in i but aga*
2.6 fi ompromise of the ditch and berm may area as a result of some precipitation events, orary. The maximum berm height will be water runoff flows off and around the each, and the peak Probable Maximum pad, the estimated depth of the flow is es (Adden u of Attachment B). The storage pad area is ee times the area from which run-on might emanate, thus the land flow results from the storm water that falls directly on the pad.
the storage area is predominately a sand dune area with little to ths, which has the effect of lessening the overland flow of at area mg the storm events. In order to provide a conservative flood effects, the flood events are modeled without including the and berms, which provides the greatest possible area contributing playa.
ed in Section 4.0 of the December 2016 revision of the March 2016 report Centralized Interim Storage Facility Drainage Evaluation and Floodplain ysis (Attachment B of SAR Chapter 2):
Page 2-26
WCS Consolidated Interim Storage Facility Safety Analysis Report Revision 3 Interim "The local PMP [probable maximum precipitation] floodplain analysis yielded the PMF elevation near the CISF site of 3488.9 ft ms!. Elevations of the storage pads vary from 3490 ft msl to 3504 ms!. Elevations of the foundations of the security/administration building and the Cask Handling Building are 349 3493 ft msl, respectively."
The finish floor elevations of the Security and Administration bu*
Handling Building are 7 feet and 4 feet, respectively, above t will not be impacted by the PMF. The detailed calculation level elevations in the playa can be found in Attachment B.
2.4.2.3 Effects of Local Intense Precipitation 2.4.3 2.4.4 The Flood Plain Study in Attachment B inclu year frequency storm event and the limits additional storms that were modeled descrio wide that is too distant from the WCS CISF to There are no streams or river Draw, an ephemeral stream, is miles west of the WCS CISF in by flooding on streams of rivers.
nage and is about 3 would be unaffected e
typically dry, the maximum histo
- per second 0, 1972 and measured 36.2 cubic meters o
The Waste Control urrently have five (5) manmade evaporation mentation contra and evaporation. In addition to the WCS ponds, f manmade ponds to the southwest in New Mexico. As indicated in xi mum elevation of the embankment structure of any of these inimum elevation of any structure at the CISF. If a seismic failure, the inherent topography would preclude any adverse eiches are typically observed on lakes or seas. There are no surface water on or near the WCS CISF where such a phenomenon would be a concern at the WCS CISF. There are currently five evaporation ponds at the te Control Specialists site and they are designed with spillways on the south side so any seiche or surge would flow south away from the WCS CISF.
Page 2-27
RAls and Responses Enclosure X to E-XXXX RAI NP-2.4-3:
Provide clarification as to what is the exact design of WCS CISF rail side track, in p section east of the storage area.
In its 2016 floodplain analysis, ISP considered four drainage areas in the wa encompassing the WCS CISF (i.e., P DA 1, P DA 2, P DA 3, and P DA4, 2-35). ISP stated that drainage area P DA 3 contains 42.8 acres and dr portion of the CISF site bounded by the existing WCS railroad and t that surface water runoff from P DA 3 discharges into the large pl a
(SAR Chapter 2 attachment B).
In reviewing the SAR, the NRC determined that the easter are not consistently identified in the site plan depicted i versus that depicted in SAR Figure 2-35 and SAR C 2.2.1-1. The drainage area P DA 3 depicted in the for than that depicted in the latter. Difference in the area of flood water level on the south eastern corner of the storag correctly depicted in SAR Figure 2-35, the NRC staff request design in SAR Figures 2-1, 2-3, 2-4 and If drainage area SAR Figure 2-1, the NRC request that floodplain an Figure 2-1.
in SAR Figures 2-26 and 2-35, which are in 2-1, 2-3, 2-4, and 2-15 show the rail for 2-1, 2-4, and 2-15 have been updated wn for orientation purposes only and that and 2-35. SAR Figures 2-26 and 2-35 both the location o rail line and the drainage playa for drainage 3 has been updated in response to RAI NP 2.2-2 and no longer Page 10 of 119
WCS Consolidated Interim Storage Facility Safety Analysis Report Revision 3 Interim Figure 2-1 Waste Control Specialists Facility Site Plan Page 2-68
WCS Consolidated Interim Storage Facility Safety Analysis Report Revision 3 Interim Figure 2-4 Wind Rose Location Map Page 2-7 1
WCS Consolidated Interim Storage Facility Safety Analysis Report Revision 3 Interim Top of Casing Elevation aaystone Claystone (ft msl)
(ft bgs)
(ft msl)
PZ-36 3498.49 75.0 3419.79 3499.88 77.1 3419.49 3505.87 87.4 3414.98 3503.78 87.0 3413.60 3415.44 3511.79 3515.00 93.5 3418.29 3433.99 3502.08 3504.80 65.3 3436.78 3436.07 3490.40 3493.75 52.5 3437.90 3430.88 3485.45 3488.66 51.0 3434.45 3436.78 3487.06 3490.20 47.1 3439.96 3436.09 3484.19 3487.39 45.4 3438.79 55.55 3435.60 3487.77 3491.15 49.8 3437.97 65.24 3429.59 3491.56 3494.83 58.7 3432.86 49.02 3438.47 3484.17 3487.49 43.3 3440.87 55.21 3438.01 3490.17 3493.22 50.5 3439.67 56.46 3434.68 3488.00 3491.14 51.5 3436.50 Figure 2-15 Boring Locations in the Vicinity of the WCS CISF Page 2-88