Photo: Near the bottom of reactor 1 PCV. Molten debris can be seen in the upper middle part of this photo. (16.03.2022) [Link]
The crippled reactor 1 in the Fukushima nuclear plant presumably had the damage worsened due to the intense earthquake that happened on the 16th of March, 2022.
The earthquake, which hit the Fukushima nuclear plant again at midnight of the 16th of March local time, had the epicenter in Fukushima offshore and the magnitude was 7.3. The seismic scale was measured to be 6+. Tepco confirmed the water level decreased by 20cm in reactor 1’s primary containment vessel (PCV). Though Tepco reported it was merely a temporary decrease related to the air pressure change and it was unlikely that the earthquake caused additional damage to the reactor, another 20cm decrease of the water level was observed during the following week.
On the 22nd of March, 2022, Tepco announced there’s a possibility that the damage in reactor 1’s PCV was exacerbated. The part that was affected by the earthquake hasn’t been identified.
The possibly newly added damage forced Tepco to increase the injection volume of coolant water by more than 50% per hour. No estimation has been calculated about the progressing vulnerability of the reactor vessels as time passes from the 11th of March, 2011 and how much the increased coolant water contributes to the overwhelming contaminated water storage.
https://www.tepco.co.jp/decommission/information/newsrelease/reference/pdf/2022/1h/rf_20220322_6.pdf
https://www.tepco.co.jp/decommission/information/newsrelease/reference/pdf/2022/1h/rf_20220324_1.pdf