GENERAL33376

• Permit No: C1982057
• IBM Index Class Name: General Documents
• Doc Date: 9/4/1991
• Doc Name: PROPOSED DECISION & FINDINGS OF COMPLIANCE FOR PR1
• Permit Index Doc Type: FINDINGS
• Media Type: D
• Archive: No

The Iles Formation i; divided into three members. ihe• sal Tcw Creek
Sand;tcna is a massive, fine grained, well Sorted sane. The icw Creek varies
from ~5 to 125 feet thick. 0v?rlying tha Tow Cr??< ir? 12'JQ feet of
~nL?r;,?tided shales, sandstones, and coal;. Tha cca~s, ;nil? mince in the
/icinity, ar? too deep to be considered ?ronomically r?COV?r3b12 a:
J2^?C3 iI-W Mine. The mdiilVe, fine gf3`ned. 100 f??L th1Ck TYJUt Cre?:<
SdncstJne is the UCO2rl1GSt unit cf the Iles FormaLiJr:.
GJnformably overlying the ales i; the Williams Fora Formation. The lower unit
of the ,Ji iliams Fork Formation is a serves of int2rJedded ;hales, 53nds :One;,
SdndV ;nal?S and Coal. The middle coal group C•in L3:nS L`1e ;?d~S Cf eCCnCmIC
I~7~CCrt3nC?. LOwB''mO;L is the Wclf Cr??k teal, whim is _Jlit irtc in upper
dnC 1Cwer unit. The lOwen 523:11 i5 dGOU: if) f?e: t~?iC:<, •.vn`le Ln? UCG?" iS
doouL 1.5 fe?t th1Ck. Thls CJdI lies tJ0 tleep •w1Lh'~' Lh2 C2rmiL ar?3 t0 Je
mined by ;urfaca me:hcd;. 100 feet 3bC'/e th? WOif Cr??< .Jai iS tha Wdd;?
COdI. The two Sedm; are ;2pdr3te7 ~Oy 1nL2rC?tided SdnC'>tJneS, ;hales,
siit;tones and thin coals. The Waage coal s?am is the most continuous in the
area and is the seam which will be extracted. The outcrop strikes about
north-south, and dips 8 to 14 d?yr??s. The Waage is a15J split into upper and
lower ;?3m;. The ICwer is two to thr?e f?et thick, and .5 secar3ted from the
10 foot thick upper seam by two to five feet of ;ha'?s ano sardstcnes.
0v?rlying the Wddg2 iS about 500 feet Of SdndStv'n2>, Sh3~?;. 3..0 COdi,
'nClUding the L?nno~ l,Odl S2 till, 'Which hdS Ce?'1 ?rJtl? i'n3v 'n C;iC?S.
Jv?rlying this low?r unit of the Williams FJrk Fcr~atJn ': the .3C ~??t thick
Twenty Mlle Santl;tone. The upper most Unl_ or Lh2 sviiliims =or< FormaLi•Jn
COn;1;tS Of interbedd?d sa.nd;tJne;, ;hales, and Chlil CJdI;.
In2 applicant has ;ubmitt?d detailed andiy5l '> Jf the 'yEOi'?~iC3l
Cnd BCt?ristiCS Of the OverDUrden anti io:2rbUrd?.^. fJUne i,n :~e ~2neC3 _'!-W
'4i n? Dermit area. The Sdmpl2d pdr3met?'i aver? 3^yr??e UCOn by the DivlSlOn,
OS~I and Peibodv Coal Company during :me?`ings held 'n 1550 and 1981.
P3^imet?ri idil!pl°_d ar? ll;tad In the pe'miL dpC11C3`iJn ~~/CluTle ?, Tab p. The
09''miL dppliCdtiOn states that theS2 par3mE:ari '.wer? 'J;2] DJ ... CCC'JmE'lt the
physical and chemical propa~ties of the cverbur.den and undErburden, to compara
these properties to ground avatar qualit/, and to d?t?rmine pctenila
reclamation success."
The data obtained from the geochemicdl analyses aver? compared to criteria
d?rived from Slate and Federal agencies CUSOP., BLM, Wy^_ming OEQ, and other;).
The rrjterid U52d fCr COmpdriiJn and re1d`.ive d?jr2?S Cf SiliCdbllity are
lilt?~ In 'Jolume 2. 30 5, Td01? 5-J, fag°_ ~- "• ChrJUgh 5-24 f Cha 02rmit
3CC11J3LiCn.
LO ~: Or Iasi C' the sdmcl?s 3ndl yZ°_'1. ~~, 3C'd/base CC:?r :'d' CC rOn.
mdng3^252, C3Cm'Um and Z`.nC a.<C?Ede7 SUiCeC_ 1?',:'i. .' 'yE^?''ai, :ae pi`/1;10n
CJnCUr; ~.vith tf2 3tlC~iC3nt~S det?rminaLion th3: nOrmd! mi.ci^e of Ove'bUrd?n
'a'il m':*,igate the tOxiC effect; Of theS2 mat?ridi5. C.J. ^Ci'hCC' in
"Selective Placement Jf Strip Hine O~rerburden in Mcnta~a" (Chapter 5, Summary
R?port, 1981) sago?sLS that if the '/clume Jf tc%ic mat" it 's 1?ss then 15Y
Cf Lne COLdI volume cf mdL2ridl t0 be r2tl1dC?d, dil'JtiCn Cf the tCdiC material
Cin C2 SUCC2S i~Ul.
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