Document dvL7nxnLeG3wX2VEnN7GOozB

It* me Manager, AuatrtllSQ Blue Asbestos Ltd., WITTBHOOU. KALOOORIIE. 27th August, 1957. Dear Sir, Attached Is s copy of dust counts sad tempersturee reeordsd in underground working places at year colonial.and Wlttonoom mines. Also the results of dust eouats taken la the treataeat plaat. You *111 observe that tbe dust eouats uadargrouad are < vary high* These could be lowered by ensuring that a greater vi volume of sir Is asde to flow through tbs working pieces. .Ibs asasuremsnta/of.slrflow resulted:?.' Colonial iilaet * '' Sxhaust (measured before fan) total Intake (Hsla Adit 28,750ef* Mo.l South Drive piuetuatee (aay even reverse) No.*3 South Drive U, 950cfa Ho.3 South Drive 27,000efa - 6S,500efm. 60,700cf. fflttenoon Mine: gxheust (measured poet fan) Intake (through new portal) 50,625ofm 32,650effe Air la lost through the doors la the following ouaatltlee: Through door to 1181 Crosscut " " " 1200 Crosscut " " 1600 Crosscut " " 2000 Crosscut " " " 2400 Crosscut '3,120efh. 6,430 9,100 * 5,300 " 6,600 * leaving 2,200 efm to vantllata the 2702 and 2704 Stopea. Yours faithfully. DTSTBTC.T IKSPBCTOft OP *TWg8. U 1 93? state timing Engineer, Ulnee Department, PERTH. XA1000BLXS. 23rd August, 19 I vialted Wlttenoom during tae period 131b to 171b August end instsoted uadergrouml working places-at beta Colonial and Wlttenoom. uinea: aada MMwtMau of the asJor*sirflowar- and inapaoted end secured duet count* la the tr*eMo* plant* - A copy of tut temperatures aadr dual counts recorded at imm plaosa is ..... u 7. - The majority of the ora la now being eon frota the Col onial mine where about 20 msohlaes are engaged oa atoping opera tions. mesa machines break the ora on ops shift aad on the shift opposite to the machines eerspers art used to claaa the face and moYe the broken ora into the paaeae. The ratio le approximate, one eoraper party to two meohlnee. Development le carried out by three partite, and appears to be lagging behind* At the llttat^ oat aloe the operation* ere not purely on e salvage baale. Six acreper parties ere engaged cleaning tba broksn ore from stepea end this le ezpeoted to be completed by the end of the current month. Air measurements! These were aede using a vans aaemoneter end resulted: Colonial Kina : 68,JOOefB. Intake through kata Adit 28,730cfn " through Mo.l South Drive Fluctuates (may aven reverse) " " 5o.2 South Drive u,950efm. (Flue cua tee) " " . M0.3.South 9rlve-27000efkw Tot*1 Intake. ~ -$0;700cfm. .B. la previous report* Ao.l South Srlvo and p.2 South Drive have beao refarred to sa mo.l Cliff Opeclng aad Mo.2 Cliff opening respectively but the new titles ere those oow adopted at tha alas. Tba above figures for airflow ladloste that a large vol ume of air la pausing through tbo mine, which la correct, but the path tha air takas la variabla. At oae tlaa the velocity of the air entering through the Min edit le very strong, whilst a short tins later tha velocity le practically negligible aad the air oust be entering the mine through another opening. The airflow through the no. 1 South Drive la vary small aa an lntaka and at times has baea measured se reverting. In fact there la no positive airflow through the Intake openings sod no constant path that the air adopt The cause laattributable to tha sir currents In thegorges and alo the walla of the gorge. In order.to improve the airflow it win b neceaaary to instsl doors, regulators, and fans to indues the re` oulred airflow. The attention of the mine management vae drawn to t this matter, aa well se the need for the air to be prevented from f short circuiting directly to the mein fan without pasting through i working placet. The fan inducing the airflow la a 60" Axial Flow fan in stalled at an opening to t&s mine workings on tha sastern cliff foe 500 feot north of the main adit. v.utenooB kina: Exhaust Intaka through lew Portal 50.625f 32,650ef> Tha discrepancy batwaan Intake end Exhausted air la 17,975ef. which is probably bsing snort circuited to the feo through the in-, effective seeling of old edit oeniage, and a poor stopping at tnr f*n itself. ______ ; ! 1 I) ?or tne amount of work proc#>xling la tmi alas the 33,650 cubic feet pr minute entering the ala* 1* adequate although more air could bo nada to extend to the bottom of the ala* to vent ilate the 3700 atop**. The leakage* through th* door* doa iprova condition* la *os* atop**. The loaaoa through the door* ara tabulated below:- Intak* through no* portal. loat ttirougn door In 1181 Crosscut. . Loot through door la 1300 Croaaeut. Plow Hong 1180 Drive. Lott through door la 1600 Crosscut. Ploa along 1180 Drive. Lost tnrough door in 3000 Crosscut. Plow along 1130 Drive. Loat through door In 3000 Crosscut. Plow along 1180 Drive. 33,650cfa. 3,130 " 6,U30 * 33.100 " 9.100 a 10,000 * 5.300 " 6,800 a 6,600 a 3,200 a This 3,3oCef flows to the 3700 atopas and Joining with the other sir eventually reach** the exhaust fan by **y of old worked out atop** ate. Duat Counts: The attached figures appear to me to be very high for the underground working*. rrnilst Ido consider that attention eeuld b* given to Improve th* air elreult tnrougn tn* mla* condition* underground w*r* s*tlsfcscry *ad la evidenced by th* w*t * older bulb tet^eretures. Coarsened air-water Jata nr* auppllad at th* or* pasaaa into which th* or* l* aoraped. Luring aeventy five percent of the tin* 1 spent at th* Colonial min* water wa* nos available du* to th* msln **t*r pip* to the mine being broken. This caused boring opsrstioos to be eue-ead*4 but did not affect th* scraping which continued irrespective of water being available or not. Kith the instrument. us*d for taking th* aampl* of dust, there le e tendency, particularly in e dusty a maoaphero, for future sections of tna glass sllds to b# poluted. I feel then that the results obtained under these conditions for the duat aaeples ere not * true Indication of the duet content of th* air. Treatment Plant: Little visible Improvement we* evident to th* external appearance of the treatment plant. However much la being attempted la an endeavour to lnprov* the duet collection. That section of th* plant wnleh include* the Soils. Kublt bresksr and screens hat been totally enclosed and fitted with exhaust ducts which eonaaet to duetlng leading to a Rotoeloaa dust collsetor. This duet eollcetloa appear* satisfactory. Another Rotoclon* unit la installed but as yet has not been pereemantly connected te the roof discharge from the fibre collecting eyeloao*. An Inadequate supply of power w*e given ea oo* reaeon. nhen eoaneeted a great improvement 1* expected. Pound# tlone for a third Rctoelca* dost collector have boon commenced. It 1* anticipated this will exnaus duat crested at the crushing unite inside the plant building. Plans have been prepared for the construction of e new treatment plant at the Colonial mine. 3ulldcxers aero In operstlo I evening out fill for the foundation for the site. Th* nign ele vation of the entrance to the min* on the gorge face, and the fall into the volley of the gorge should aaaiet In tn* plant layout. Th' firut oa natruetlou anticipated la tne installation of a conveyor belt In the lower tunnel, to convey th* or* free th* nine bln, to * Jaw crusher, thane* to e dynona crusher and to a storage bln. The ore *111 be carted by trucks from this bln to the treatment plant 1: vvittenoom gorge whilst tne remainder of tn* plant la ooostructed. General: At present the fibre being recovered la in the vicinity of 1000 tons per four weekly period aod t.iia from tne treatment of 17,000 tone of ore. It la envisaged that a tonnage of uo.ooo tons of ora per four weekly period will be attaiad. ,../3 C This will call for Increased working atopes anddevelopmoat *111 nave to be escaped up. -*11 this *111 repnire laproved ventilation end possibly me sinking of s ventilation shaft from the top of tne hill *111 be necessary sooner than Is anticipated at the noment. Disvaic-f INSPECTOR OP UIH33. f s t