Nob End is the site of a former waste tip, and now a Site of Special Scientific Interest (SSSI)

Site of Special Scientific Interest

A Site of Special Scientific Interest is a conservation designation denoting a protected area in the United Kingdom. SSSIs are the basic building block of site-based nature conservation legislation and most other legal nature/geological conservation designations in Great Britain are based upon...

 near Kearsley

Kearsley

Kearsley is a town within the Metropolitan Borough of Bolton, in Greater Manchester, England. Historically within Lancashire, it lies about 7½ miles northwest of Manchester,5.5 miles south-west of Bury, and about 3¾ miles south of Bolton.It is bounded on the west by Walkden, the east by...

, Bolton

Bolton

Bolton is a town in Greater Manchester, in the North West of England. Close to the West Pennine Moors, it is north west of the city of Manchester. Bolton is surrounded by several smaller towns and villages which together form the Metropolitan Borough of Bolton, of which Bolton is the...

, England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

.

Standing at the confluence of the River Irwell

River Irwell

The River Irwell is a long river which flows through the Irwell Valley in the counties of Lancashire and Greater Manchester in North West England. The river's source is at Irwell Springs on Deerplay Moor, approximately north of Bacup, in the parish of Cliviger, Lancashire...

 and River Croal

River Croal

The River Croal is a river located in Greater Manchester, England. It is a tributary of the River Irwell.Rising at the confluence of Middle Brook and Deane Church Brook, it flows eastwards through Bolton, collecting Gilnow Brook and the larger River Tonge at Darcy Lever...

 it was used around 1850-70 as a tip for alkaline waste from the production of sodium carbonate

Sodium carbonate

Sodium carbonate , Na2CO3 is a sodium salt of carbonic acid. It most commonly occurs as a crystalline heptahydrate, which readily effloresces to form a white powder, the monohydrate. Sodium carbonate is domestically well-known for its everyday use as a water softener. It can be extracted from the...

 (soda ash) by the Leblanc process

Leblanc process

The Leblanc process was the industrial process for the production of soda ash used throughout the 19th century, named after its inventor, Nicolas Leblanc. It involved two stages: Production of sodium sulfate from sodium chloride, followed by reaction of the sodium sulfate with coal and calcium...

.
The waste was known as 'galligu' and was a blue sludge (from reduced iron compounds) dominated by calcium sulphide and smelling of bad eggs. The toxicity of the calcium waste has subsided and calcicolous vegetation

Calcicolous grasslands in the British National Vegetation Classification system

This article gives an overview of the calcicolous grassland communities in the British National Vegetation Classification system.-Introduction:The calcicolous grassland communities of the NVC were described in Volume 3 of British Plant Communities, first published in 1992, along with the...

 has colonised the site.
The 8.8 hectare

Hectare

The hectare is a metric unit of area defined as 10,000 square metres , and primarily used in the measurement of land. In 1795, when the metric system was introduced, the are was defined as being 100 square metres and the hectare was thus 100 ares or 1/100 km2...

 site became a SSSI in 1988 and a Local Nature Reserve

Local Nature Reserve

Local nature reserve or LNR is a designation for nature reserves in the United Kingdom. The designation has its origin in the recommendations of the Wild Life Conservation Special Committee which established the framework for nature conservation in the United Kingdom and suggested a national suite...

 (LNR) in 2000.

In 1936 a major breach in the now defunct Manchester Bolton & Bury Canal occurred east of the Nob End locks which was never repaired.