This should be the topic line of a letter written by a government agency, you can use this format:

Re: returning a copy of the "检还固定污染源操作许可证展延申请文书" that you submitted, which we have checked


This is the whole idea:

We are hereby returning the copy of the "固定污染源操作许可证展延申请文书" submitted by your company, which we have reviewed/checked.


检还 is the standard word to start the topic line when a government department write a reply

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Note added at 2 days 9 hrs (2019-03-28 21:57:02 GMT)
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检还 is the standard word to start the topic line when a government department writes a reply to an entity.