The entry for the mine in "The Mines of the FOD" by Tony Oldham indicates that it has been explored. Not sure about recent current conditions.
The entry in the database http://www.aditnow.co.uk/mines/Bream-Grove-Level-Coal-Mine/?gowhere=%2fmines%2f%3fpID%3d2%3fpid%3d2%26aa%3d30%26ab%3d4%26ac%3dA%26ad%3d10  is rather bare.If you do explore please add what you can to encourage others. NGR is SO614049.
Best of luck.
🙂

Edit I've only just noticed that you've recently joined. So, apologies for not noticing earlier (It's my age you know :confused: ) and welcome to Aditnow.

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It was open when I went the in 1997:

Tufts Iron Mine NGR SO 6112 0498 A 325 feet L 65 yards

Bream Grove Level NGR SO 6140 0495 A 260 feet L 460 yards Connects with Tufts Level qv. There is a good parking at NGR SO 6160 0503. Walk up valley for about 100 yards and take left hand (south) fork. nb the side valley is filled with mine debris. After 50 yards an adit will be seen on your right (west).

Tufts Level NGR SO 6200 0490 A 150 feet. L 1,470 yards. A free drainage level on the western side of the syncline from which the Coleford High Delf and Whittington seams have been worked, in addition to the Trenchard Seam, which was 4½ feet thick. The adit was driven through to the iron ore deposits in the Drybrook Limestone in 1914-1919.

References: Field 37; Log Vol 21 Entry No 090597 p 42, p 94 abandoned as a water supply due to pollution from a piggery, p 105 Chloridation equipment renewed in 1966, p 108 refers to rodding in 1973. RFoDCC N/L 114 p 6 workings broken into by contractor. Bad air noted; Sibley 51 - 53; Trotter p 75

stolen from

The Mines of the Forest of Dean.

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