S.LANCS. &. N.CHES. ADVISORY PLANNING COMMITTEE
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COAL AND SALT GENERA LISED MAP
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Coal and Salt Areas I I)
\L :\RE.\.
A. A RE.\S COLOURED GREE:-1.- These are situated within the coalfield and will be st bl hr at least ten years. They comprise areas where : a e (1) Coal has been exhausted and nothing remains worth working.
(2)
ome coal still remains, but mines are not likely to be re-opened under predictable economic conditions during the next ten years.
(J) ~lining may take place at great depth or in thin scams, so that subsidence will be small
and non-destructive.
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B. :\HE.\S CoLOURED RED.-These areas are unsafe for bu ilding and include the following of su bsidencc, etc. : -
(r) Ground under which coal is in process of extraction and destructi,·e subsidence is in process. (2) :\rcas in which coal has been left and the mines may be re-opened, or into which
present workings may extend within ten years with consequent destructive subsidence. (3) :\ reas recently worked out where subsidence may continue for any period up to tt'n years. (4) :\reas "·here subsidence will lower the surface to below free drainage level and cause flooding. (5) :\rcas where virgin coalfield will be entered within the next ten years either by extension of present workings or by sinking a new shaft or opening adits. C. .\RE \S CoLOU RED PALE PtNK.- This indicates the limits of the workable coalfield as . r as can be determined from geological deductions. Broadly these areas can be diYided into t
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(r) Those fringing or extending into the Cheshire Basin. (2) Those within the coalfield which have not yet been explored and developed fo r a Yariety of reasons. It will be clear that the chief factor which will limit the extension of the field into or Cheshire will be depth. Depth is in itself dependent on rate of dip and on faulting "hich may throw down the coals to below the limit practicable for working under present t•mditions. The limit of workings set by depth is determined largely by temperature, distance which it is practicable to haul coal underground, gradient and ventilation problems. ~Iany areas indicated in the map as containing coal reserves are problematical, since no boring has been done which would indicate the depth and nature of t he coal measures and geological d ·ductions have been made on very slender evidence. t ''' ards
Those areas within the proved coalfi eld where development has not taken place are less vroblematical. This apparent lack of interest is due mainly to thick glacial deposits which c n·er large tracts of the coalfields and have prevented early exploration . There is every probability that these areas will be explored and developed, but t hey are and contain less coal than the areas fringing Cheshire.
~mailer
= REFERENCE==~
\LT .\ RE.\S
D.
AREAS
COLOURED YELLOW.- Salt underlying t hese areas is a possible source of
!:>ltbsiden~e . AREAS LIKELY TO 8£ AFFECTED BY SVBSIDBNCE
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AREAS WJTHJN THI! CO.U.PIELD UNLIKELY TO BE A FF.EC TED UV J'l/RTKER Sl1BSIDB111CE
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PROBABLil LIM ITS OF UNDEVELOPED COALFI ELD AREAS WITH UNDE RLYING ~LT
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CLASSlt' lED HOADS RAIIJ\V.\.VS, TWO TRACKS MORE TIIA.~ TWO TRACKS NAVIGABLE \\~\TERW\YS RESEitVOillS , l:iTC. BOUNDARIES,
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ADVISORY AllEA
RFAIIONAL PL.i\NNIN6 (OMMI'ITE£S - · -·SCALI-~ I
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