From 1993 to 1999 Ron Treadgold (top right) recorded the memories of his work friends from the Royal Gunpowder Mills. Either in person at their house or by phone recording their conversations in his shed.
Both the Southsite (now Gunpowder Park) and the Northsite (the Waltham Abbey Gunpowder Mills visitor attraction) are steeped in history. You can explore some of that history here.
You may also want to visit the Waltham Abbey Gunpowder Museum.
There is a link to their web site on page 2 of the potted history section of this web site.