Last edited on 2011-06-01 04:07:55 by stolfi

Fukushima Daiichi
Units #1, #2, #3
Corrections to the data

Jorge Stolfi
2011-03-22 (updated 2011-05-29)

Some of the data from the sources used were almost certainly typos and were corrected (hopefully) for the plots.

Reactor #1

• 2011-03-12 to 2011-03-13, the SLP1 source seems to record some "B" core pressures (well above 300 kPa) as "A" pressures (which are generally well below 300 kPa). Swapped as seemed fit.
• 2011-03-14 19:30 to 2011-04-07 12:00, the readings of core pressure "B" in the NISA releases 023--079 were consistently below those given in the SLP1 source. The readings of the other pressues in those releases were similar but apparently less precise than those of SLP1. The discrepant NISA readings were discarded.
• 2011-03-15 18:43 and 01:24, the SLP1 source apparently swapped the "A" and "B" core pressures. Swapped back.
• 2011-03-15 18:43 and 01:24, the SLP1 source apparently swapped the "A" and "B" core pressures. Swapped back.
• 2011-03-16, 6:00, the core pressure was given as "0.62 MPa" in the NIRS table. Corrected to "0.162 MPa".
• 2011-03-19 03:30, the SLP1 source gives the torus CAMS reading "B" as "1.45E+1" Sv/h, but adjacent values suggest that it should be 4.45E+1 Sv/h. Corrected.
• 2011-04-20 15:00:00, the SLP1 source gives the torus CAMS reading "B" as "1.04E0" Sv/h, but adjacent values suggest that it should be 2.04E0 Sv/h. Corrected.
• 2011-04-22 06:00, core pressure "A" was 536 kPA in NISA release 107, 541 kPa in SLP1. Retained 541 kPa.
• 2011-04-22 12:00, core pressure "A" was 541 kPA in NISA release 108, 531 kPa in SLP1. Retained 541 kPa.
• 2011-04-23 00:00, core pressure "A" was 541 kPA in NISA release 109, 544 kPa in SLP1. Retained 541 kPa.
• 2011-05-26 05:00, NISA release gives the torus pressure as 35 kPa. Neighboring values are 100 kPa. Note that the drywell pressure of reactor #2 is precisely 35 kPa. Presumably a transcription error. Discarded the reading.

Reactor #2

• 2011-03-14 06:00, the entry is incorrectly dated "2011/3/15 6:00" in SLP2.
• 2011-03-14 18:38, the entry is incorrectly dated "2011/3/14 18:40" in SLP2.
• 2011-03-15 06:02 to 07:20, SLP2 gives the torus pressure as "0 kPa". Changed to "99999" (missing) instead.
• 2011-03-16 01:35 to 14:00, NIRS drywell pressure values "A" in range 58--78 kPa, while the SLP2 values are in the range 220--450 kPa. Retained the NIRS values.
• 2011-03-20 11:00, the drywell CAMS reading "A" was given in the SLP2 source as "1.34E+1" Sv/h. Adjacent values suggest a typo. Corrected to 6.34E+1.
• 2011-03-20 15:00, the CAMS reading in the drywell was given as "6.25×10^-1 Sv/h" in NISA's Release 37. Corrected to "6.25×10¹ Sv/h".
• 2011-03-24 09:00, the core pressure "A" is given as "-134 kPa" (gauge), which is nonsensical; while the NISA relase N048 gives -37 kPa gauge i.e. 64 kPa absolute, consistent with adjacent readings. Retained the N048 reading and discarded the SLP2 one
• 2011-04-04 11:00 NISA release N073 gives the water level "A" as -1600 mm, SLP1 says -1500 mm. Retained -1500.
• 2011-04-24 12:00, the drywell pressure is given as 73 kPa in NISA release N111, but as 83 kPa in SLP2. Retained the latter.
• 2011-04-22 06:00 NISA release N107 gives the water level "A" as -1600 mm, SLP1 says -1500 mm. Retained -1500 mm.

Reactor #3

• 2011-03-11 between 20:00 and 21:00, the SLP3 entry dated "3/11　20:??" was discarded. (Could be 2011-03-11 20:50 based on core pressure readings.)
• 2011-03-12 08:30, the entry is duplicated in source SLP3
• 2011-03-13 09:20, the source SLP3 contains two entries with this date, with slightly different values. Assuming that the first one is earlier, based on readings; re-dated it as 2011-03-13 09:19.
• 2011-03-20 16:00, the NISA N037 note gives the torus pressure as "800 kPa" (twice the nominal maximum!) while SLP3 has 400 kPa. Discarded the N037 value.
• 2011-03-21 10:00, the SLP3 source gives the core pressure "A" as "-500 kPa" (!). Perhaps it was -50 kPa? Assumed it was "down scale" (1 kPa abs).
• 2011-04-20 00:02, NISA press release N098 and the next four releases gave the drywell CAMS reading "A" with the wrong exponent "×10¹ Sv/h" instead of "×10^-1 Sv/h" (a factor of 100). Corrected on 2011-05-07 per TEPCO errata of 2011-04-24.

Other corrections

A couple of other insignificant errors noted in the TEPCO errata above were also corrected on 2011-05-07 and on 2011-05-29.

Disclaimer

IMPORTANT: These plots, scripts, and data files are provided "as is", for the reader's convenience, with no guarantee whatsoever. There may be errors in the original document and/or in my processing of it.

This page is NOT an official document of the State University of Campinas (UNICAMP). Neither its author (me) nor UNICAMP should be held responsible for any damages that may result from the use of this information. Corrections and suggestions are welcome.