The cache is not at these coordinates.
The coordinates given are of the junction of the Grand Union Canal with its Slough Arm.Junction of Slough Arm with Main Line of the Grand Union Canal
The Slough Arm of the Grand Union Canal was the last canal to be built in England, other than the Manchester Ship Canal. It was authorised in 1879, opened in 1882. It was built to transport bricks from brickworks along the canal to Slough into London. There are no locks on the arm, nor are there indeed on the Paddington Arm into London, nor on the Regents Canal from Paddington as far as Camden. Thus, Camden to Slough is one of the longest lock-free stretches of canal in the country. This winning combination of level transport and high market demand for bricks, made the canal a commercial success despite being built long after the Great Western Railway.
The Slough arm is almost straight and almost East-West. In its short length it crosses no fewer than three delightful aqueducts.
The canal is now somewhat neglected, though still navigable. There are water lilies and iris growing in the rarely disturbed water and the little-used towpath provides a lovely flat route to cycle along. So this is a cache best done by bicycle. Long trousers and sleeves are however recommended as there are very tall nettles in places.
In common with most English canals, the navigation is narrower than the length of most of the vessels that travel along it. This means that boat skippers cannot turn around wherever they like, but must continue to a place that is wide enough to turn. These special widenings are called "winding holes" (pronounced "win-ding" not "wine-ding"). The Slough Arm has more than its fair share of winding holes for its length, presumably because it is not a thoroughfare.
Thus, boats can turn at the junction, at the marina entrance close to the junction and at the various winding holes. The cache is located at the middle one of all the possible turning points between the tow path and the canal.
The cache is a camouflaged 35mm film canister containing a bison capsule and pencil. The log sheet is inside the bison capsule - please put the log back into the lid, then screw on the body. On the back of the stash note is the Confirmation Code (all upper case) that you need to note to log the cache.
You can narrow the search area with a bit of studying and then check your coordinates on Geochecker.com
. (Note: CacheID on Geochecker is TC9JU as this was formerly listed as a Terracache.)