All surfaces inside the building should be of impervious material to permit thorough washing.

建筑里所有的表面都应当用不透水的材料这样可以彻底清洗。

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The coal and limestone storage yard must have a bottom impermeabilization system. This system may be constituted by a clay layer, a geomembrane layer, or other impervious material.

煤料和石灰石存放场必须有底部防渗系统。该系统可由粘土层、地质处理用膜层、或其他防渗材料组成。

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The coal and limestone storage yard must have a bottom impermeabilization system. This system may be constituted by a clay layer, a geomembrane layer, or other impervious material.

煤料和石灰石存放场必须有底部防渗系统。该系统可由粘土层、地质处理用膜层、或其他防渗材料组成。

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