Document g0bgkZ1BRM99VG2LEgD8J4gN

PLAINTIFF'S EXHIBIT ENVIRONMENTAL SURVEY EL PASO PLANT February 9-23, 1976 Prepared by: John B. Richardson, Environmental Specialist Lowell D. White, Environmental Scientist Department of Environmental Sciences ASARCO Incorporated Salt Lake City, Utah > Report Date: June 10, 1976 Distribution WRKelly KDLoughridge DHSoutar KWNelson LCTravis AJGillespie,Jr./JTStetson RCBeckstead EHHaug/WTSweat Dp.CHHine wMOVarner r EXHffirr 2.n ENVIRONMENTAL SURVEY El Paso Plant February 9-23, 1976 TABLE OF CONTENTS Page Executive Summary ....................................................................................... i I. OPERATING CONDITIONS .................................................... 1 II. SAMPLING PROCEDURES A. Air................................................................................................... 1 B. Noise............................................................................................. 2 III. SAMPLING RESULTS A. Air 1. Tape Samples................................................................ 2. Personal Monitoring ......................................... 3. General Area Samples......................................... 4. Asbestos Sampling ............................................... 5. Sulfur DioxideSampling - Stationary. 6. Sulfur DioxideSampling - Personal . 7. Settled Dust Sampling ................................... 3 5 11 12 12 14 14 B. Noise............................................................................................. 15 IV. COMfffiNTS A. Lead Department................................................................ B. Copper Department .......................................................... C. Zinc Department................................................................ D. Cadmium Department.......................................................... E. Mill, Sample Mill.......................................................... F. Leach Plant, Umpire Lab, El Paso Lab . . G. Sulfur Dioxide Sampling ......................................... H. Asbestos Samplingand Use...................................... I. Noise............................................................................................. J. Biological Monitoring ............................................... K. Welding........................................................................................ 20 21 21 22 23 23 23 24 24 26 26 V. RECOMMENDATIONS.............................................................................. 26 VI. GRAPHS VII. PHOTOGRAPHS ENVIRONMENTAL SURVEY EL PASO PLANT February 9-23, 1976 EXECUTIVE SUMMARY Tape sampler and personal monitoring data continue to show airborne lead concentrations in Dross Reverb, Sinter Plant, Blast Furnace, Zinc Fuming, Zinc Kiln, and Cadmium Areas in excess of the OSHA standard. Sulfur dioxide concentrations were above permissible limits on the Reverb charge deck, and are attributed to larry car activity. Noise dosimeter data for tuyere punchers and rail car unloaders reinforce the finding of the previous survey that noise exposures to these individuals exceed the OSHA standard. Recommendations include: enclosing Dross Reverb and Cadmium crane cabs; providing supplied air respirators to those workers who samples exceeded OSHA heavy metal standards by a factor greater than ten (Dross Reverb furnaceman. Sinter Plant fireman and two beltmen. High Grade Sample cutters and Cadmium firemen); modifying rail car unloading facilities (reduce noise and dust levels); sampling semi-annually for determination of asbestos exposure and eligibility for medical examina tion; and requesting Material Safety Data Sheets for masonry and welding products. \ environmental survey report EL PASO PLANT I. OPERATING CONDITIONS On February 9, 1976, No. 2 Blast Furnace went down. On February 16, 1976, No. 1 and No. 3 Blast Furnaces were shut down and No. 2 Furnace brought in. Because of the drop in furnace slag production, the Zinc Fuming Furnace went down on February 16, 1976, and remained out of operation until February 19, 1976. No. 1 Blast Furnace came back on line about noon of February 20, 1976. The Dross Reverb Furnace ceased operating on February 11, 1976. S.C.S. curtailment was instituted as necessary. Otherwise, all other processes were normal. II. SAMPLING PROCEDURES A. Air: 1. One-hour sequential samples of fugitive emissions were collected with RAC Model G-2 tape samplers at the following locations: Date Feb.1976 General Area Specific Area 10-11 12-13 13-15 11-12 12-13 13-14 14-15 15-16 15-17 19-20 19-20 20-21 20-21 Dross Reverb Reverb II Converters fl II It Zinc Fuming V If II II fl It Cadmium II Charge Deck - south wall " " - southeast corns Near Matte Tapping Area Between No.2, No.3 Converters Between No.l, No.2 Converter control panels Between No.l, No.2 Converters Rear of No.2 Converter Between Main and Holding Furnaces Fuming Furnace Charge Deck - north side Holding Furnace - south side Fuming Furnace Charge Deck - south side Northwest corner of Godfrey Roaster Godfrey Roaster Feed Floor The above samples were analyzed for lead, cadmium, copper, and zinc by atomic absorption spectrophotometry. Selected samples were also analyzed for arsenic using the silver diethyldithiocarbamate (SDDC) colorimetric method. i 2. Individual dust and fume samples were collected with M.S.A. personal monitoring devices equipped with closed-face (plastic cover in place and inlet plug removed) Millipore filters (0.8 micron pore size). These samples were analyzed for lead, cadmium, zinc, and copper by atomic absorption spectrophotometry and for arsenic by the SDDC method. Total particulate weight was determined by weighing filters before and after sampling. 3. General areas samples were collected with M.S.A. personal monitors equipped with closed-face Millipore filters (0.8 micron pore size), and analyzed for lead, zinc, cadmium, arsenic, and total particulate as described above. 4. Individual asbestos fiber samples were collected with M.S.A. personal monitoring pumps equipped with open-face Millipore filters (0.8 micron pore size). The asbestos fibers were counted using a Zeiss phase-contrast micro scope, according to methods specified in the NIOSH criteria document. 5. Sulfur dioxide concentrations were determined at stationary locations using M.S.A. personal monitors equipped with midget impingers. The absorbing solution was 3% hydrogen peroxide. Analysis was by the titrimetric method cited in the NIOSH Criteria Document for Sulfur Dioxide. 6. Personal and general area ^sulfur dioxide measurements were taken by employing $ gas adsorbing dosimeters. These samples were analyzed by the manufacturer. 7. A composite sample of settled dust was collected in the mill. The sample was analyzed for percent free silica by using the modified Talvitie method, as recommended by NIOSH. Noise; Individual noise exposure data were collected using DuPont Permissible Audio Dosimeters, Model D-100, which measure noise exposures in terms of the present 90 dBA OSHA standard. A DuPont Audio Dosimeter Readout Model R150 was utilized to decode each dosimeter memory cell and produce a reading as a percentage of the current 90 dBA standard. III. SAMPLING RESULTS A. Air: 1. Tape Samplers Depart ment Location Starting Time (1976) Anal- Cone1 n. (mg/nr) ysis Mean Max. Min. Percent No. of Exceeding Hourly Graph OSHA Limit Samples No. Lead Charge Deck- 2/10 Pb .98 (1) 4.35 .10 91 Dross south wall 3:02pm Reverb As .43 1.30 .08 20 22 1 51 Copper Converters Between Converter Nos. 2 s 3 2/11 Pb .41^ 1.57 .05 57 23 2:01pm Cu .20<2> .71 .05 65 (Fume) 23 0 (Dust) 2 -- Between Converter Control Panel Nos. 2 & 3 2/12 1:22pm Pb Cu .15 .16<2> -- -- --0 100 (Fume) 0 (Dust) -- Between Converter Nos. 1 & 2 2/13 Pb .14 .43 .04 22 23 5:41pm Cu .14<2) .63 .02 48 (Fume) 23 0 (Dust) 3 As i 054 .055 .051 0 3-- Rear of No.2 2/14 Pb .15 .70 .03 26 23 Converter 4:26pm Cu .11(2) .53 .02 30 (Fume) 23 0 (Dust) 4 Copper Reverb Charge Decksoutheast corner 2/12 Pb .15 12:46pm Cu 1.24(1) .38 4.14 .06 13 24 .16 100 (Fume) 46 (Dust) 24 -- -- Near Matte Tapping Launder As 2/13 12:48pm Pb Cu .06 .14 .11 5.0 .59^^ 2.10 Zinc Filming Furnace Between Main and Holding Furnaces As 1.40(1) 5.70 2/15 7:45am Pb Zn .12 .02 1.69 .23 As .06 .19 .02 0 (Dust) .02 42 .06 81 (Fume) 19 (Dust) .14 50 .02 3 .002 0 .02 0 43 43 8 34 34 7 5 -- 5 -- -- Tape Samplers (cont.) Depart- went Location Starting Time (1976) Anal- Conc'n. (mg/m ) ysis Mean Max. Min. Percent No. of Exceeding Hourly Graph OSHA Limit Samples Ko. Zinc Fuming Furnace (cont.) Fuming Furnace Charge Decknorth side 2/15 4:14pra Pb Zn As .26(1) 1.72 .87 3.91 .14 .48 .04 .16 .007 29 0 0 24 6 24 4 Holding Furnacesouth side 2/19 12:05pm Fuming Furnace Charge Decksouth side 2/19 12:10pm Pb .06 Zn .01 Pb .25(1) .10 .04 .70 Zn 3.81 As .05 17.97 .06 <.006 .003 .06 .09 .03 0 17 0 17 54 25 29(ZnO Fume)25 04 7 8 Cadmium Godfrey Roasternorthwest corner ground level 2/20 11:00 am Cd Pb .08 . 07 .29 .24 Godfrey Roasterfirst floor 2/20 1:30pm Cd 1.69(1,3)6.0 Pb .46(1) 1.20 .006 .02 24 (Fume) 3 (Dust) 10 29 29 .13 100 (Fume) 96 (Dust) .04 74 27 27 9 10 11 Footnotes: As .05 .10 .03 0 5 (1) Mean exceeds OSHA 8-hour tims-weighted average (TWA) limit. (2) Mean may exceed OSHA 8-hour TWA limit depending upon type of exposure. i.e. ,, dust and/or fume. (3) Mean exceeds OSHA ceiling value for cadmium dust,, which should be exceeded at no time during the S-hour shift. * 24-hour sample. Tape sampler did not advance to give hourly sample s. CURRENT OSHA STANDARDS Substance Pb As Cd Cu Zn OSHA PROPOSED STANDARDS Pb As OSHA 8-hour TWA Limit (mg/m^) 0.2 0.5 0.1 0.2 0.1 1.0 5.0 (Fume) (Dust) (Fume) (Dust) (as ZnO Fume) 0.1 0.00-1 OSHA Ceiling Value (mg/mJ) _ -- 0. 3 0. 6 -- -- - .01 (1 5-mlr.utc sample) 2. Personal Monitoring Depart ment Employee Name and S.S. No. Job Title (Respirator Use) 1976 Date and Shift Samp ling Time (Min) Analysis Lead Dross Reverb Craneman \" (yes) 2/11 f -- / 365 D Pb As Total Part. Furnaceman / : (yes) 2/11 D 363 Pb As Total Part. Cone'n. (mg/m3) .88 .107 2.26 2.40 (1) .514(1) 5.43 Lead Sinter Plant Fireman ; (yes) Fireman (yes) Beltman (yes) Beltman : (yes) 2/21 A 2/21 A 2/21 A 2/21 A 479 Pb As Total Part. 2.14 (1) .05 8.12 477 Pb Total Part. .78 (1) 4.02 463 Pb 2.12 (1> Total Part. 25.79 (1) 464 Pb 2.0 As .027 Total Part. 10.21 Lead Blast Furnace 920 Cat eOperator (yes) Furnaceman ~ ' (yes) 2/18 D `r 325 2/11.- ' 368 D Pb As Total Part. Pb As Total Part. .11 .011 .83 2.67 .052 8.19 Cadmium Charge Car Operator (yes) Fireman (yes) 2/11 D 357 2/13 - ; 443 A Pb Total Part. Cd Pb As Total Part. .38 (1) 1.50 2.40 (1' 1.74 (1) .062 13.69 Crane Operator (yes) \ 2/13 D 369 Cd Pb 1.75 (1 1.15 (I" As .059 Total Part. 10.41 Asst. Fireman 2/13 344 Cd 2.23 (1 (yes) D Pb .92 (L Total Part. 10.47 2. Personal Monitoring (cont.) Depart ment Cadmium (cont.) Employee Name and S.S. Mo. Job Title (Respirator Use) Fireman v"-:' (yes) 1976 Date and Shift Samp ling Time (Min) 2/18.,464 D Analysis Cd Pb Total Part. Fireman (yes) 2/13 A : 460 Cd Pb Total Part. Core' n. (mg/m3) .52(1'' .35(1) 2.88 3.78C1, .16 11.23 Zinc Kilns Kiln Loader " (yes) 2/13 D 338 Pb Zn As Total Part. 1.42<1> 5.34(2) .097 9.61 Kiln Loader (yes) 2/13 D 340 Pb Zn Total Part. .47(1) 1.58 3.95 Kiln Loader (yes) 2/12 . 482 A ~'- Pb Zn Total Part. .08 2.07 4.58 Asst. Foreman- 2/13 329 Pb (yes) D Zn .65(1) 1.73 As .043 Total Part. 4.76 Kiln Operator (yes) 2/12 A 363 Pb 2.39d) Zn 6.22(2) As .091 Total Part. 12.94 - Kiln Operator 2/12 481 Pb 1.52d) (yes) A Zn 7.43(2) As .078 Tote 1 Part. 14.69 Kiln Operator (yes) 2/13:, ` 334 D Pb Zn As Total Part. .11 .19 .053 4.91 Kiln Operator (yes) 2/12 A 422 Pb Zn Total Part. .40d) 1.32 3.14 East Helena 2/16 443 Pb .36d) Zinc Dust A Zn .17 'l .v Unloader (yes) As Total Part. .021 20.97(1) 2. Personal Monitoring (cont.) Depart ment Employee Name and S.S. No. Job Title (Respirator Use) 1976 Date and Shift(5) Samp ling Time (Min) Analysis Cor.c1 n. (mg/m3) Zinc Kilns (cont.) a East Helena Sn 2/12 .v : 361 Pb .8S(1) Dust Unloader D Zn 4.59 (yes) Total Part. 6.40 Zinc Fuming Furnace z Zinc Fuming Fumaceman (yes) 2/12 D 352 Pb .15 Zn .06 Total Part. 17.77^ Zinc Holding Furnaceman (yes) 2/12 D 291 Pb .15 Zn . 60 Total Part. -4.06 Zinc Fuming Furnace Helper. Chairge Deck (yes) 2/12 D 342 Pb .27(1) Zn .81 As .018 Total Part. 4.90 Copper Con verters Craneman . (yes) 2/13. 484 A' Pb As Cu Total Part. .24d) .07 .24(2) 3.00 Craneman (yes) 2/1.6 A 488 Pb Cd Cu Total Part. .14 .02 .34(2) 1.96 Craneman (yes) 2/16 A 485 Pb .13 As .028 Cu .08 Total Part. 1.44 Craneman (yes) 2/16 A 486 Pb .15 As .023 Cu .12(2) Total Part. 1.53 Crane Chaser (no) 2/11 ' 313 A Pb As Cu Total Part. .05 .039 .04 1.09 Skimmer (no) 2/11 A 319 Pb . 24 (D As .019 Cu .08 Total Part. 1.80 2. Personal Monitoring (cont.) Department Employee Name and S.S. No. Job Title (Respirator Use) 1976 Date and Shift(5) Sampling Time (Min) Analysis Copper Converters (cont.) ' a Puncher (no) 2/10., 325 Pb A As Total Part. Core 1 n. (mg/m3) .10 .02 3.57 Copper Roasters Fireman >(yes) 2/11/-' - 323 A Pb As Cu Total Part. .03 .011 .50^ 2.66 Feederman -e (yes) 2/11 A 330 Pb .04 As .012 Cu .11(2) Total Part. 12.19 Copper Reverb Matte Tapper v' ' (yes) 2/10at;- 344 A Pb Total Part. .03 1.43 Tapper Helper1 (yes) 2/10 A 344 / Larryman ^ ' (yes) 2/10 A 352 Waste Heat *. Boiler Lancer (yes) 2/16 <- ' ' 479 Pb As Cu Total Part. .03 .011 .27(2) 10.25 Pb As Cu Total Part. .07 .047 2.89 7.63 Pb As Cu Total Part. .04 .035 .04 1.64 Waste Heat Boiler Lancer (yes) 2/16 A 476 Pb Cu Total Part. .03 .06 . 65 Waste Heat Boiler Lancer (yes) 2/16 A 476 Pb .06 As .031 Cu .14C2) Total Part. 1.31 Mill Waste Heat Boiler Lancer (yes) Unloader (yes) 2/16 A 292 Pb Cu Total Part. .04 .06 .71 2/18 ' 342 D Pb Total Part. 1.28{1) 46.19(-) Free Silica= 0.7% OSHA DUST LIMIT (based on free silica content 11.11 2. Personal Monitoring (cont.) Depart ment Employee Name and S.S. No. Job Title (Respirator Use) 1976 Date and Shift(5) Samp ling Tims (Min) Analysis Cone'n. (mg/r.3) Mill (cont.) Feederman . (yes) 2/18.-. 350 Pb .12 D Total Part. 5.96 Free Silica== 0.7% OSHA DUST LIMIT (based on free silica content) == 11.11 Unloado.ng Clean-up ' (yes) 2/19,. A 454 Pb As Total Part. .12 .015 2.73 Motor Crane Operator Y-" (yes) 2/19 A 474 Pb .07 Cd <.01 As .006 Total Part. 1.08 Sample Mill Boiler Shop Switchman " " (yes) High Grade Sample Cutter (yes) High Grade Sample Cutter (yes) High Grade Sample Cutter (yes) Welder (yes) 2/19 A 474 2/13^,. 357 2/18 D 351 Pb Total Part. .03 .74 Pb .42< As "3 (1) Total Part. 149.34' ; Pb .60^) (1) Total Part. 213.51' 2/18 D 2/18 D 353 Pb .32d) As .016 Total Part. 42.74d) 346 Pb .07 Cd < .01 As .01 Total Part. 6.43 Leach Plant Umpire Lab Welder (no) Helper \ . (yes) Operator (yes) ,, Fire Assayer \(no) 2/19 - . 475 D 2/18 c-.-. 474 D 2/18 D 478 2/19 ' D 474 Pb Cd Total Part. Pb Total Part. Pb Cd As Total Part. Pb As Total Part. .10 .01 3.06 .24d) 1.0S .46 (1) .10 .013 1.43 .42d) . 002 1.81 2 Personal Monitoring (cont.) Depart ment El Paso Lab Employee Name and S.S. No. Ore Bins Copper Cottrell Job Title (Respirator Use) 1976 Date and (5) Shift15' Samp ling Time (Min) Analysis Fire Assayer' ' (no) 2/18 509 D '; ` Pb As Total Part, Fire Assayer (no) Fire Assayer (no) Beltman (yes) ' 2/19 ' D 430 2/19 D 431 ` 2/21a.,,. 463 A Pb total Part. Pb Total Part. Pb As Cu Total Part. Beltman (yes) 2/21 A 471 Pb Cu Total Part, Operator ' (resp. use unknown) Conditioner Man (unknown) 2/19 A 2/19 A 465 Pb Total Part 456 Pb As Total Part Cotyc'n. (mg/m3) .19 .008 1.57 .11 .64 .07 .52 .17 .02 .78 6.43 .19 .57 3.23 .04 .19 .04 .006 .22 3. General Area Samples: Depart ment Cadmium Location Office, north wall 1976 Date & Shift(5) 2/22 A Sampling Time (Min.) 330 Lunch Area, north wall 2/22 A 335 * Zinc Kiln Office, west wall 2/16 D 464 Kiln Area Lunch Room, 2/16 west wall D Fuming Furnace Control Room, operator's desk 2/16 D Lead Office, west wall 2/16 D Copper Reverb Office, northwest corner 2/16 D 448 428 390 414 Copper " Office, east wall Anode 2/16 D 442 Boiler Shop On Lighting Panel 2/19 D 378 Analysis Cd Pb Total Part. Cd Pb Total Part. Pb As Zn Total Part. Pb Zn Total Part. Pb As Zn Total Part. Pb As Total Part. Pb As Cu Total Part. Pb As Cu Total Part. Pb Total Part. Cone'n (mg/m13 42 5 .04 .03 .55 .04 .03 .73 .02 .009 .87 1.72 .06 .10 .96 .05 .004 .11 1.28 .10 .008 .79 .14 .082 .05 4.18 .04 .007 .04 9.94 .07 .32 FOOTNOTES (Personal Monitor and General Area Samples) (1) Exceeds OSHA 8-hour TWA limit. (2) May exceed OSHA 8-hour TWA limit, depending upon type of exposure, i.e.f dust and/or fume. (3) Exceeds OSHA ceiling value for cadmium dust'. (4) May exceed OSHA ceiling value, depending upon type of exposure, i.e., dust and/or fume. (5) Shift Notation: D = day A = afternoon FOOTNOTES (Personal Monitor and General Area Samples) (cont.) CURRENT OSHA STANDARDS: Substance Pb As Cd Cu Zn Free Silica (Si02) Total Particulate OSHA 8-hour TWA Limit (mg/m3) 0.2 0.5 0.1 (Fume) 0.2 (Dust) 0.1 (Fume) 1.0 (Dust) 5.0 (as ZnO fume) 50 mg/m3 % quartz + 2 15 mg/m2 OSHA Ceiling Value (mg/m2) 0.3 0.6 OSHA PROPOSED STANDARDS: Pb As 0.1 0.004 0.01 (15-minute sample) 4. Asbestos Sampling Because of heavy dust loading on the filters caused by Blast Furnace caulking, asbestos fibers were not recognizable for counting. 5. Sulfur Dioxide Sampling - Stationary Depart ment Con verter Location Stairway between #1 5 #2 control panels 1976 Date & Shift 2/10 A 2/11 D Sampling Time (Min.) 285 375 Sampler Type Dosimeter Impinger Dosimeter Impinger 2/20 D 496 Dosimeter Impinger #2 Control Panel 2/13 260 Dosimeter D Impinger Concentration (mg/mJ) (ppm) 4.4 1.7 5.7 2.2 0.8 0.3 2.5 0.9 2.1 22.0 0.8 8.4 W 0.5 ' 2.4 0.2 0.9 Sulfur Dioxide Sampling - Stationary (cont.) Depart ment Location Converter (cont.) Above and be tween #1 & "2 converters 1976 Date & Shift(2) Sampling Time (Min.) 2/20 D 502 Sampler Type Dosimeter Impinger Crane #2 Cab 2/11 340 Dosimeter D Impinger Reverb Charge Deck, south side above reverb 2/10 A 2/11 D 2/13 D 385 366 348 Dosimeter Impinger Dosimeter Impinger Dosimeter Impinger Charge Deck, 2/20 500 Dosimeter north side of D Impinger charge ports Charge Deck, south side of charge ports Front of reverb, ground floor Front of reverb, charge deck, south of con verter slag receiving port 2/20 D 2/20 D 2/20 ' D 499 532 508 Dosimeter Impinger Dosimeter Impinger Dosimeter Impinger Roaster Center of fire floor 2/10&13 D 488 Dosimeter Impinger Concentration (mg/m^) (ppm) 2.6 1.0 8.2 3.1 1.0 4.6 2.9 9.9 39.0 8.3 25.0 9.8 141.0 18.0 0.4 1.7 1.1 3.7 14.6(1) 3.1 9.5(1) 3.7 54.4<1) 6.8(1) 19.0 10.8 7.4(1) 4.1 5.7 9.4 12.0 21.7 2.2 3.6 4*5n , 8.3(1'4 16.0 12.1 6.1(1) 4.6(31 6. Sulfur Dioxide Sampling - Personal Department Converter Roasters Reverb Blast Furnace Employee Name and S. S. No. Job or Operation Clean up Skimmer #1 Crane Operator Crane Operator Skimmer "2 c Feeder Fireman Mucker \ '* Feeder 1976 Date & Shift ' 2/12 A 2/10 A 2/11 D. 2/12 A 2/10 D 2/11 A 2/11 A 2/10 . A' 2/10 A Samp ling Time (Min.) 340 403 340 330 370 329 342 405 408 Concentration (mg/mJ) (ppm) 8.1 3.1 7.3 2.8 1.8 0.7 3.6 1.4 5.2 2.0 1.0 0.4 4.2 1.6 10.0 3. 9 0.8 0.3 Footnotes - Sulfur Dioxide Sampling (Stationary and Personal) (1) Exceeds OSHA 8-hour TWA limit for sulfur dioxide, which is 5 ppm. (2) Shift Notation: D = day A = afternoon (3) Some spillage from one of three impingers in set. (4) Solution from one of three impingers evaporated. 7. Settled Dust Sample Laboratory analysis showed the free silica content of Mill dust to be 0.7%. This percentage has been applied to personal samples collected for total dust in the Mill. B. Noise: 1. Employee Samples Depart Employee ment S. S. No. Job Title Samp 1976 (7) ling Date & Time Shift (Min) Adjusted ^ ,, Sound (3) Hearing Dosimeter (1) to Level Protec Readout 8 Hours Exceeded tion'. (Percent) (Percent) 115 dBA? Copper Roasters Fireman 2/11 A 338 No 56 80(5) Yes Feeder- 2/11 man A 324 No 3 4 No Copper Anode -- 2/11 A 321 No 7 10 NO Anode Caster 2/11 A 231 No 10 21 No Copper Converters Skimmer 2/11 A Crane Chaser 2/11 A 309 305 No Yes 23 17 36 No 27 No Puncher 2/10 D 372 Yes 14 18 No Puncher 2/10 D 372 Yes 95 123 (5) Yes Puncher 2/10 A It 2/12 A i Puncher 2/10 A 408 321 405 Yes Yes Yes 0 178 228 o 266 (4) 270 (4) Yes Yes Yes Puncher 2/11 A ii 2/12 A 312 318 Yes Yes 16 71 25 107 {5) Yes Yes Puncher 2/12 A Foreman 2/12 A 319 285 Yes No 32 354 48 ` 596(6) Yes Yes Employee Samples (cont.) -16- Depart- Employee merit S.S. No. Copper Con verters V- Copper Reverb Power House Job Title Samp 1976(7) ling Date Tims Shift (Min) Adjus ted ^ Sound Hearing Dosimeter TM to Level Protec- Readout 8 Hours Exceeded tion (Percent) (Percent) 115 dBh? Middle 2/11 Crane D Operator 335 No 0 o () No South 2/12 Crane A Operator 347 No 11 15 No North 2/12 Crane A Operator 330 No 28 41 No Middle 2/12 Crane A Operator II 2/13 A 339 No 480 No 35 22 50 Yes 22 Yes Larry 2/10 Motorman A 393 No 24 29 Yes Tapper Tapper 2/11 D 2/11 D 292 No 315 No 2 117 3 178(4) No Yes Furnace- 2/11 man D 317 No 32 48 Yes Foreman 2/10 D 290 No 34 56 No Helper 2/10 D 361 No 38 50 No Helper 2/13 A 385 NO 45 56 No Helper tl 2/10 A 2/13 A 415 No 378 No 57 15 66 No 19 No Employee Samples (cont.) Depart- Employee ir.snt S.S. Mo. Blast Furnace Sinter Plant - Ore Bins Copper Zinc Fuming Furnace Job Title Samp 1976 (7) ling Date & Time Shift (Min) Adjusted ^ Sound Hearing Dosimeter TM to Level Protec Readout 8 Hours Exceeded tion (Percent) (Percent) 115 d3A? Furnace- 2/10 346 No man D 104 144 (4) No, Furnace- 2/10 333 No man D 116 167 (4) Yes Furnace- 2/10 man A 385 No 165 206 (4) Yes Furnace Feeder 2/10 A 388 No 172 213(4) Yes 00 o Asst. Furnace Feeder 2/10 A 412 NO 0 No Fireman 2/13 405 No A 60 71 ' No Fireman Fireman 2/13 A 2/21 A 395 482 No No 123 150 149 149(4) No No Fireman 2/21 A 482 NO 77 77 No Beltman 2/21 A 467 No 6 6 No Beltman 2/21 A 467 NO 44 45 No a Beltman 2/21 A 472 No 2 2 No Beltman 2/21 A Furnace- 2/11 man D Furnace Helper Charge Deck Laborer 2/11 D 2/11 D 464 325 319 322 No No No No 2 60 53 39 2 89 (5) 80(5) 58 No Yes Yes Yes Employ ee Samples (cont.) -18- Depart- Employee r,int S.S. No. Zinc Kilns Cadmium Sample Mill Mill Job Title Samp1975 1 ling Hearing Dosimeter Date & Tims Protec Readout Shift (Min) tion (Percent) Asst. 2/13 355 No Foreman D 32 Operator 2/13 340 No D 70 Laborer 2/13 345 No D 94 Craneman 2/13 373 No D 5 Asst. 2/13 373 No Fireman D 48 Asst. 2/13 445 No Fireman A 7 Head Bucker 2/17 403 No D 4 Sample Cutter 2/17 398 No D 33 Sample Cutter 2/17 392 No D 1 Foreman 2/12 282 No D 2 Beltman 2/12 304 No D 49 Unloader 2/12 301 No D 53 Unloader 2/12 300 NO D 34 Tripper 2/12 293 No man D 20 Feeder- 2/12 290 No man D 70 Feeder- 2/12 283 No man D 35 Adjusted 2 (3) Sound to Level 8 Hours Exceeded (Percent) 115 dSA? 43 Yes 99 (5) 131 (5) No Yes 6 No ' 62 Yes 8 No 5 No 40 No 1 No 3 77 (5) 85<5>' No Yes Yes 54 Yes 33 No 116 (5) Yes 59 No Footnotes for Personal Noise ExDOSures: (1) Readout based on elapsed sampling time. (2) The 8-hour adjusted readout is an extrapolation of the original dosimeter reading. This extrapolation assumes that the employee will be exposed to the same noise level during the remainder of the shift when the dosimeter is not worn. (3) The OSHA noise standard does not allow employees to be exposed to sound levels greater than 115 dBA. However, experience to date shows that most dosimeter measurements greater than 115 dBA are the result of employee mischief, i.e. shouting into the microphone of the dosimeter. Therefore, these data must be interpreted cautiously. (4) Dosimeter readouts greater than 100% indicate a violation of the OSHA noise standard. However, the accuracy of the dosimeters (as specified by A.N.S.I. SI.4 - 1971)is * 2 dBA which translates to an upper confidence limit of 133%. Therefore, only readings greater than 133% are a positive violation of the OSHA noise standard. (5) Readings from 75% - 133% fall within the dosimeter calibration limits and may be violations of the OSHA standard. (6) Suspectedtampering. (7) Shift Notation: D = day A = afternoon (8) Dosimeter probablydid not record properly. IV- COMMENTS -20- A. Lead Department: The tape sampler mean concentration (0.98 mgPb/m3 Graph 1) and craneman personal monitor result (0.88 mgPb/m3) both indicate excessive lead levels in the Dross Reverb Area. The Dross Reverb furnace went down about noon on February 11, 1976, the day the craneman and furnaceman personal samples were collected. Although operations were not normal, hourly tape sample results beginning 3:00 p.m. on February 10, show levels consider ably above the 0.2 mg/m3 OSHA limit for lead a full day before scheduled shut down. Three of the four Sinter Plant personal samples, in addition to the Dross Reverb furnaceman result, were an order of magnitude greater than the current OSHA 8-hour TWA limit for lead. Half-mask respirators, equipped with standard dust and fume cartridges, are routinely worn by these employees. However, their use is authorized in atmospheres containing up to ten times the OSHA lead standard only. These four workers are borderline for being required to wear more acceptable respiratory protection, such as supplied air respirators. It is recognized that such equipment would seriously limit worker mobility and possibly create a safety hazard, if dragging along air hoses is involved. Full facepiece respirators could also be used, provided these do not cause undue discomfort and are well received by the workers. The new Sinter Plant planned for El Paso may affect substantial reductions in airborne lead concentrations and thereby remedy the situa tion. The Dross Reverb Area is not scheduled for modifica tion, so the continuing problem of excessive airborne lead concentrations in this department goes unresolved. Serious consideration should be given to enclosing the Dross Reverb crane cab and providing heating,ventilation and air condi tioning, as recommended in prior survey reports, as an initial step. The blast furnaceman personal sample (B.Sosa - 2.67 mgPb/m3) was taken the same day the Dross Reverb furnace ceased operating, and therefore may have been influenced by fugitive emissions from the Dross Reverb Area. The Sosa sample result suggests that more adequate respiratory protection is indicated, such as a supplied air respirator or a full facepiece respirator. The stationary personal sampler placed in the Lead Plant Office showed a concentration of 0.10 mgPb/m3, which is at the 8-hour TWA limit being proposed by OSHA' as a new lead standard. B. Copper Department: -21- Of the six sets of tape samples collected, only one (between Coverter Nos. 2, 3 - Graph 2) recorded a mean lead concentration above the current OSHA limit. At one station (Reverb Matte Tapping Launder) the average of eight hourly samples was almost three times the current OSHA standard for arsenic. It is important to note that the mean lead concentration at all six tape sampler locations exceeded the proposed OSHA lead standard of 0.10 mg/ra^ based on an 8-hour TWA. Spot checks for arsenic consistently demonstrate levels considerably above the proposed OSHA limit for inorganic arsenic, which is 0.004 mg/m-3. T . _ (Craneman) and (Skimmer) personal samples in the Converter Area were above the OSHA TWA limit for lead. The other fourteen Copper Department personal samples were below the OSHA lead standard. The arsenic limit as proposed by OSHA was consistently exceeded, as verified by personal sampling data. Stationary personal samplers located in the Reverb and in the Anode Offices demonstrated acceptably low airborne lead levels. The scheduled enclosure of the Converter Building, which accommodates three converters, a reverberatory and a holding furnace, a zinc fuming and a holding furnace, and two anode furnaces, is'welcomed as a partial answer to low level emission control and applauded by the Texas Air Control Board as a positive step toward enhancement of community air quality. On the other hand, from an occupational health standpoint, the repercussions of enclosure are viewed, at best, with guarded optimism. At present, El Paso is tread ing, a fine line between compliance and non-compliance with the-present OSHA lead standard inside the Converter Building, as measured by tape and personal air sampling in both past and present surveys. Most personal samples collected in the most recent study violate the proposed OSHA lead standard. Should enclosure concentrate to any great degree or even localize fugitive emissions within the building, the burden of trying to comply with even the air quality portion of the proposed OSHA lead standard may prove intolerable. Lead was singled out as one example. The same comments could equally apply to sulfur dioxide, copper, and possibly to other air contaiminatns, such as arsenic. C. Zinc Department: Both tape sampler locations on the Fuming Furnace charge deck showed mean lead-in-air concentrations in excess of the OSHA TLV limit. The Ochoa personal sample (Fuming Furnace charge deck helper)also showed an excessive airborne lead level. It is noteworthy that the tape sampler positioned on the charge deck's south side (Graphs 7 and 8) ran during the Fuming Furnace start-up period (slag from one Blast Furnace) and recorded more hourly excursions above the OSHA 8-hour TWA for lead and zinc oxide fume than did the sampler on the charge deck's north side (Graph 6), which sampled when the furnace was operating normally (slag from two Blast Furnaces). Personal and tape sampler results indicate that this area would be hard-pressed to comply with the proposed OSHA airborne lead standard. The Control Room stationary personal sampler recorded minimal airborne lead concentrations. Personal monitor data for Kiln workers and East Helena fume unloaders continue to show unacceptably high airborne lead concentrations. Eight of the ten Zinc Kiln personal samples violated the OSHA 8-hour TWA for lead. One (OlivasKiln Operator) exceeded the limit by a factor greater than ten. Improved dust handling procedures need to be instituted. East Helena fume unloaders continue- to occupy the same enclosure as the car being unloaded. This procedure should be modified to reduce personal dust exposures. The possi bility of erecting a platform outside the enclosure, where dust unloading could be viewed, should be considered. As an alternative, a spray fog system within the enclosure may serve to reduce dust levels without clogging dust handling equipment. Both stationary samplers (Lunch Room and Kiln Office) showed acceptable airborne lead levels, under both current and proposed OSHA standards. Cadmium Department: Uncontrolled Godfrey Roaster emissions, material handling, and blowing dust contribute to excessive airborne cadmium and lead levels in the Roaster and Mixing Areas, as repeatedly shown by tape and personal sampling. The cadmium dust OSHA ceiling limit (never to be exceeded) is consistently violated. Because dust and fume respirators are approved for dust concentrations up to ten times the applicable TLV, in this case cadmium, the firemen and cranemen should be provided with supplied air or full facepiece respirators until effective engineering controls can be implemented. These controls may include sealing roaster leaks and ventilating the charge conveyor. The craneman may be alternately protected by sealing the crane cab and supplying tempered air through a high efficiency dust filter, such as High Efficiency Particulate Air (HEPA) filter. Paving the yard area may serve to decrease blowing dust. Frequent water spraying or covering with an emulsion of petroleum oils and resins may also control yard dust. -zs- Stationary samplers (Office and Lunch Room) showed acceptably low cadmium and lead levels (see photo). E. Mill, Sample Mill: Personal samples for A.Valdez (Mill-Unloader), R.Pax, L.Esparza and H.Fournier (High Grade sample cutters) were above the permissible limit for lead. However, exposures were probably due to lead sulfide, which is much less soluble than lead oxide or elemental lead. Total particulate concentrations in the Mill and in High Grade were excessive and indicate the need for respirators more suitable than the dual cartridge,half face mask variety presently in use. Supplied air respiratory protection should be provided during high grade sample cutting. The Valdez personal sample also exceeded the OSHA silica dust standard based on free silica content. F. Leach Plant, Umpire Lab, El Paso Lab; Dust handling with front end loaders probably can be credited with causing dusting in the Leach Area. Both operator and helper personal sample results were above the OSHA TWA limit for lead. Of four fire assayers sampled in the two labs, only one (F.Gonzales-Umpire Lab) showed unacceptable levels of airborne.lead in the personal sample. Mr. Gonzales should definitely wear a NIOSH-approved dust and fume respirator during fire assay work. The other fire assayers should wear respir ators during fire assaying as a matter of good industrial hygiene practice. Engineering controls or process venti lation should be investigated to decrease airborne lead levels in the fire assaying area of the Umpire Lab. G. Sulfur Dioxide Sampling: Walden Gasbadges were used concurrently with impinger sampling trains at stationary locations as part of an on-going study to determine the feasibility of using dosimeters only in evaluating workroom SO2 concentrations. The impinger method is considered accurate at higher SO2 concentrations, but may be subject to titration errors up to 25 percent at concentrations less than 1 ppm. The higher impinger values may be due in part also to contam ination from the lip of the impinger during transfer of the absorbing solution to the vial for shipping. The dosimeters appear to be influenced by excessive heat, causing artificially high readings. Sulfur dioxide impinger data should be accepted as most nearly approach ing the true value, except in the case of spilled or dried-up impinger solutions. A total of eight impinger and dosimeter samples exceeded the present OSHA SO2 standard. Five of these samples were collected on the -24- Reverb Charge deck. These data indicate that larry cars should be covered to prevent release of SO2 in transit to the charging area, as is the practice at Tacoma. None of the dosimeters employed for personal sampling showed levels above the 5 ppm OSHA SO2 standard. Six impinger samples and nine gasbadge results were above the limits prescribed in the OSHA proposed standard for S02 H. Asbestos - Sampling and Use; Heavy dust concentrations generated during Blast Furnace caulking effectively masked any asbestos fibers collected on the open-face Millipore filters. No fiber counts were possible. Shorter sampling times and wetting down to suppress dust may aid future sampling endeavors. To comply with OSHA regulations, asbestos sampling should be conducted at six-month intervals to determine asbestos concentrations in the breathing zones of furnace caulkers, masons, and any other plant personnel who may use asbestos. In addition, all employees exposed to asbestos (exposure level not defined by OSHA) should receive an annual comprehensive medical examination. It may be helpful to maintain a roster on these individuals. Several Quigley products were noted in the Brick Mason Shed, namely Plastic Insulcrete, Heathcrete, Q-Chrome and Insulag AF. An inventory of Kaiser Lo-Set S-405 was also observed. These bags contained no asbestos disclaimers. The respective manufacturers should be requested to provide a written state ment or a Material Safety Data Sheet for each product. The manufacturers' reply should specifically address the subject of asbestos content. I. Noise: The Ldpez dosimeter result (Fireman-Copper Roasters) was within the calibration range of the dosimeter (75-133%) and therefore may be a violation of the OSHA 8-hour TWA limit of 90 dBA. The 115 dBA ceiling___limit, which should never be exceeded, was surpassed. The exursion over the ceiling value is probably traceable to burner noise as Lopez was rabbling. No hearing protection was observed. Anode Casting, Power House and Ore Bins dosimeter data were all within permissible limits. The measurements taken from Converter tuyere punchers con tinue to demonstrate unacceptably high 8-hour average readings Of sixteen dosimeter samples collected, two were definite and three were possible violations of the permissible 8-hour limit One dosimeter result was a blatant case of employee mischief (C.Smith-Foreman) . Ten of the sixteen samples exceeded the 115 dBA ceiling limit- The ceiling value data should be interpreted cautiously because employees are prone to tamper with the instruments. For example, the violations of the ceiling value recorded by the --v. dosimeters (Middle Craneman) are suspect, because the data for the other cranemen indicate that no such noise exposures appear possible. (Tapper-Copper Reverb) used an air hammer to clean out launders. His dosimeter showed violations of allowable 8-hour and ceiling limits for noise. Of the lead workers sampled, six of their dosimeters recorded definite violations of the OSHA 8-hour TWA limit for noise. One additional sample may be a violation, because it falls within calibration limits of the dosimeter. Three excursions above the ceiling limit were recorded by dosimeters worn by two blast furnacemen and one blast feederman. Manual tuyere punching may explain the ceiling violations in the case of the furnacemen. The feederman*s activities were not observed. Burner noise may also explain ceiling value violations for several zinc and cadmium workers. Four samples collected in the two departments fall within the dosimeter calibration range, and may be violations of the OSHA 8-hour TWA limit. Higher noise levels than those presently found in the Sample Mill can be expected in future sampling when the rolls are operating. Mill dosimeter results reinforce the data which were collected during the last survey. By enclosing the rail car being un loaded and keeping the employees outside the enclosure, both noise and dust levels recorded by personal sampling instru mentation could be reduced. Mill workers, including rail car unloaders, who remain close to the car when the car shaker is in operation, were observed to wear no hearing protection. To forestall future workmens' compensation claims of occupa tional hearing loss, the wearing of hearing protection should become a rigidly enforced program in all areas demonstrated in present and past reports to have average noise levels in excess of the OSHA 8-hour TWA limit or excursions above the OSHA 115 dBA ceiling limit. Workers in extremely noisy areas, such as tuyere punchers and rail car unloaders, should be given an audiogram every six months instead of annually. These audiograms should be reviewed by a physician or a qualified consultant to deter mine if noise induced hearing loss is occurring. A welladministered audiometric program, with feedback to plant safety and supervisory personnel, can pinpoint breakdowns in the hearing protection program and provide the necessary surveillance over negligent employees. J. Biological Monitoring: As of June 1, 1976, there are seven employees above Asarco's action list and five on the confirmed list for excessive blood lead levels. Of the seven exceeding the action level, three are D&L employees (Foreman, Operator and Beltman), two are Blast Furnacemen, one is a Baghouse Helper and one is a Boilermaker in the Shop. The five confirmed employees include a D&L Fireman, a Boiler Shop Helper, a Blast Furnace Cat Operator, a Pipefitter, and a Zinc Kiln Tender. It is disturbing that two of the five who are confirmed are main tenance personnel. One employee.on the action list is also a shop worker. Supervisory personnel should stress the importance of wearing respirators into production areas where many repairs occur. Supervisors should also exemplify the importance of respirators by carrying and wearing respirators in high exposure areas. K. Welding; The two personal samples collected from welders in the Boiler Shop are acceptably low for lead, cadmium and total particulate i was not using available exhaust ventilation as he welded steel plate. He also wore no respirator. -v.c . had no available flexible hose exhaust ventilation as he welded with manganese and so-called P-5 rods. - wore respira tory protection. Depending upon the metal being welded and the type of metal coatings, fluxes, and other combustibles (e.g., cleaning solvents) at the weld site, toxic gases and aerosols produced from welding may include ozone, carbon monoxide, carbon dioxide nitrogen oxides, phosgene, hydrogen fluoride, acreolin, metal fumes and other hazardous substances. The Department of Envi ronmental Sciences is desirous of obtaining a description of El Paso's welding operations and a list of the welding rod inventory to plan for future sampling. El Paso is to be complimented for installing exhaust ventila tion at welding stations. Employees should now be encouraged to use it. If not available, such as on location in the plant, respirators should be worn. V. RECOMMENDATIONS A. Crane cabs in the Dross Reverb and Cadmium Departments should be enclosed and provided with filtered, tempered air. B. Zinc fume unloading should be modified so that lead exposures to unloaders may be reduced, as described in Comments. C. Personal exposures to Godfrey Roaster workers should be reduced by sealing roaster leaks, exhaust ventilating the charge conveyor, and paving or coating the yard area with a dust suppressant. D. Until engineering controls are implemented. Cadmium cranemen and firemen should be provided with supplied air respirators or full facepiece respirators. E. High Grade sample cutters should wear supplied air respirators or full facepiece respirators. F. Fire assayers should wear NIOSH-approved respirators for dust and fume during fire assay work. G. Semi-annual asbestos sampling should be conducted at El Paso. The Department of Environmental Sciences will be happy to coordinate the project with plant personnel. H. A determination should be- made of how many El Paso employees are exposed to asbestos in their work. Based on this deter mination, annual medical examinations should be provided. I. Material Safety Data Sheets or disclaimer letters should be requested from Quigley & Kaiser regarding asbestos content of their products. J. Mill unloaders should be protected from car shaker noise by enclosing the rail car or providing a sound booth. Until engineering controls are realized, it is urged that the wearing of hearing protection be strictly enforced. K. Workers in extremely noisy areas, such as tuyere punchers and Mill unloaders, should be given semi-annual audiograms. Feed back to supervisors should be established in cases where significant threshold shifts are observed. The supervisors may then more closely monitor the wearing of hearing protection L. Maintenance personnel shown to be above the action level or confirmed for high blood lead should be reminded to wear respirators in production areas and in any visible dust or fume Production workers above the action level or with confirmed high blood lead levels should have their work, respiratorwearing and personal hygiene practices reviewed, as outlined in the Asarco Lead Hygiene Program. M. El Paso is requested to furnish D.O.E.S. with a listing of the types of welding conducted in the shop areas and the kinds of welding rods used. It may be necessary to contact vendors to determine the composition of the various rods. Material Safety Data Sheets may be available from them upon request. JBR/LDW:bj s Enel. ( John BB.. RRiicchhaarrddssoonn ^ Environmental Specialist Lowell D. White, Ph.D. Environmental Scientist 0 H u oo UV-/ O Ui o ft c O o o H < 12 N 6 12M 6 i?w Tim< r Of Lay *A .ir ,b o r n e Lead "* ~ Oiayis J: -- ...................... ----------------------------------------- ` -- -- .... !": f Location: Converters C* Xm V ^ * *^W^ -k **** . i 11 i -- - -L- rT_ " 1 r r* **P t;l 1 - --r -I- \ Ull * J . * 1 ^ Ht *-/ -L. J/ / U i. - .j 1 _- t 1 . i --* *~r-- Average Pb cone n: u.14 mq/mJ 1 \it *i `1 1 i 1 * 'i 1 s __________ t ...................... -- f.: i< ' i 1` * i* 1 1 ... ' | -* .1 ' 1 - 1 -- i1 1t ft;. ; 1! ii , i -j- 1J f i! [ 1 t , 11 ; :t .i ; 1 *` l ,1 ..1 ---- il 11 i *. St i r, H-- i ; .t 1 ;1 t ' ; 1 : i-t-'-. i1 * i i i : |i l l 1 . r --- ... [ * , ;; j 1; i : : . ; , *. ---------------- 'i ii '': >'i i -; i .i '. i . i i.. I-77-- ---- \` 'it 1t: ,; . : *i \' 1( j <: It 11 .; i i 1:.; - 1 . l' ... 1 ... _ j : ' i_ * ..it ' 111 .| ;t i. ii. . ! 1 1 | -! 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Mj i ii li 12N 6 12M Time of Day 6 12 N `) 3 m / i / f' L n (i v Lead A irb o rn e 12 M 6 12 M Time of Day 6 6 12 M Time of Lay iom 6 12 N A irb o rn e C o n c e n tra tio n (m e/m 3 ) - 12 N 12M Time of Day 2.0 n 1.5 1.0 0.5 A irb o rn e C o n c e n tra tio n 6 1 OM 6 12M 12 N A ir b o r n e L e a d ( inc / m" ) A irb o rn e Lead ^ 10.0 nc: 7.5 C o 4-1 u<0 4J c QJ O 5.0 C O CJ <U c So 2.5 12M Time of Day 12 N 5crJ f3 O J O c S-l o xu> H 12N 6 12M 6 1?M Time of Day . Uncontrolled converter emission contribute to background levels of various airborne contamin ants in the Converter Building. Time of Day . '10,'T 6 6 12M 12 N A irb o rn e Lead (me/m3 ) A irb o rn e Cadmium (in.