Then the measures of slot concrete cutoff wall were taken to the dam of Yongji reservoir.

同年开始了除险加固工程，对永记水库的防渗问题采用沟槽混凝土防渗墙处理。

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Then the measures of slot concrete cutoff wall were taken to the dam of Yongji reservoir.

同年开始了除险加固工程，对永记水库的防渗问题采用沟槽混凝土防渗墙处理。

youdao