# EXAMPLE #3 CITED IN PUBLIC COMMENT: EPA REGION 

### IX WASTE MANAGEMENT DIVISION, RCRA ENFORC EMENT OFFICE, RCRA COMPLIA NCE EVALUAT ION J NS PECTION REPORT FOR ASARC O INC . RAY COMPLEX HAYDEN SMELTER (APRIL 

### 16, 2002) (UNOFFICIAL COPY)/'\ :·· , "" ';:; II'

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### 0 ·;:-; ::! . 2 ')) UNITED STATES ENVIRONMENTAL

# PROTECTIO**;t.GENgj** S 

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# ~**~** REGION IX c:- _. -:> u , :- ·**~ ~** **.~ 1**  75 Hawthorne Street · .-..::., .· 

### • . ; y San Francisco, CA 94105 

# '<c-.,. .</**z~**



### APR 1 

### 5 ?OOZ Neil A. 

### Gambell Environmental Services Manager Asarco Inc . Ray Complex Hayden Smelter P . O . Box 8 Hayden, AZ 85235 Certified Mail No. 7000 1670 0009 31229883 Certified Receipt Requested In reply, refer to WST-3

Warning Letter, Certification of Violation Correction. and Request for Infonnation On Augu st 14-17 , 2000, and September 20, 2000, a hazardous waste investigation was conducted by repre s entatives ofthe United Sta tes Environmental Protection Agency ("EPA " ) at the Ray Complex in and ncar Hayden , AZ , EPA Identification Numbers AZD 008 397 127, AZD 000 626 606, and AZD 008 397 184 . During the course ofthis investigation, information was gathered in accordance with Section 3007 ofthe Resource Conservation and Recovery Act ("RCRA"), as amended [42 U . S .C. 6927] . 1\. copy ofthe investigation report is enclosed for your information and re sponse. The repo rt describes conditions at the facility at the time of the investigation, and identifies areas of noncompliance with RCRA regu lations and potential violations of the Arizona authorized program under RCRA Subtitle 

### C. Any omissions in the report shall not be co nstrued as a determination of compliance with all applicable regulations . We apologize fo r the delay in i ss uing this report. Several of the regulatory issues addressed in this report were influenced by recent regulatory changes and court deci s ions, and we re sim ilar to issues affecting other industry facilitie s. While this effort contri buted to the delay in issuing this report, we believe that it also contributed to the quality of o ur analysis. We welco me any updated information you wish to submit. Asarco ' s actions during the investigation and your submittal, dated August 23, 2000, adequately address all of the violations noted during the in spect ion, and all but one of the issues discussed in tb c report. Under the provisions of Section 3007(a) ofthe Resource Conservation and Recovery Act (RCRA), 42 U . S .C. 6927(a) , the EPA may require persons subject to RCRA to fumisbinformation necessary for EPA to administer the A1 ; t Pursuant to EPA's authority set fonh in Section 3007(a), you are requested to submit the following information: 1) A copy of**~e** one-time written notice submitted pursuant to 40 CFR 

### § 266.1**00~!;);** and , 2) Documenta tion demonstrating that the spent refractory brick from Asa rco' s precious metals refinery in Amarillo, Texas does not significantly affect the residue, pursuant to 40 

### CFR § 266.112(b); or 3) As a n alternative to submitting the above information (1 and 2), a copy ofthe notice submitted pursuant to 40 CFR 

### § 261.4(a)(J7)(v). lfthis option is used, please also submit certification signed by a duly authori zed representative of Asarco's Amarillo, Texas precious metals refinery (the generator of the spent refractory brick) and your facility (the destination of the spent refrdctory brick) that the spent refrdctory brick is handled at 

### aJJ times in compliance with 40 CFR § 261.4(a)(J7). Section 3008 ofRCRA, 42 U . S . C. 6928 , authorizes the initiation of 

### a civil enforcement proceeding for failure to respond fully to 

### the information request set out in this letter. Section 3008 also authorizes criminal prosecution for knowingly making a false statement or omitting material information. By copy of this letter, EPA is providing the S t ate of

### Arizona with notice of the referenced violations ofS ubtitle C ofRCRA, and is providing the State with notice that it ·intends to take no further enforcement action for 

### the violations that have been noted in the report. The State of Arizona may noti fy EPA of its intent to assume or decline responsibility to take further action to add re ss the referenced violations . Pending receipt ofthe information requested above, EPA reserves the right to take fmther enforcement action as it deems appropriate . Violations of Subtit le C ofRCRA may be punishable by civi l and crimina l actions, includi n g penalties of up to $27,500 per day for each violation as provided by Section 3008 ofRCRA. EPA routinely provides copies ofinvestigation reports and related documents to state agencies . and upon request, to the public. Such releases are handled according to the Freedom of Information Act regulations (40 CFRPart 2). If yo u believe this report, or the information submitted in response to this letter, contains or will contain privileged or confidential information, you**m~y** make a claim within fifteen ( 15) ca lendar day s from the date of this letter. EPA will con strue your failure to furnish a timely claim as a waiver of the confidentiality claims . Your response to this Warning Letter, due within 15 calendar days of your receipt of this letter, shall be mailed to :Barry Cofer Mailcode : WST- 3 RCRA Enforcement Office U.S. EPA, Region 9 75 Hawthorne Street San Francisco, CA 94105 Jf you have que stions or comments related to the technical aspects of the investigation report or thi s Jetter, please contact Bany C ofer at (415) 972-3303 or Kaoru Morimoto at (415) 972

- 3306.

Enclosure cc (w/o enclo sure): Sincerely, ___........-;·**-~ ·.**  ....**{** a i .f_ ,_..**--** / ./. / _t. ' · 

# r: Frances Schultz, Manager RCRA Enforcement Office

Laura Malone, Arizona Depanment of Environmental Quality Greg Workman, Ari7.ona Department ofEnvironmental QualityUNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION IX 75 Hawthorne Street San Francisco, CA 94105 

### WASTE MANAGEMENT DIVISION



### RCRAENFORCEMENTOFRCE COMPUANCE EVALUATION INSPECTION REPORT Purpose: Facility:

Mailing Address : 

### U.S . EPA 

### ID Number: Date ofInvestigation : 

### U. S. EPA Inve s tigators :

Sta t e Representative : RCRA Compl i ance Evaluation Inspection Asarco Incorporated 

### Ray Complex

- Hayden S melter Plant 640 

### Asarco A 

### venue Hayden , AZ Asarco Incorporated

- Ray Complex Box8 Hayden, AZ 85235 

### AZD 008 397 127 

### August 14-17, 2000,and 

### September 20, 

### 2000 Barry Cofer RCRA Enforcement Officer (415)947 :3303 

### co fer. bany@epa .go'' Kaoru Morimoto Environmental Engineer (4 15) 972

-3306 

### France s Schultz Mr.nager, RCRA Enforcement Office ( 415) 972-3297 

### Greg Workman Hazardous Waste Section Manager Arizona Department ofEnvironmcntal Quality (602) 207-4138Facility Representatives:

Report Prepared Dy : Report Date : Neil A. Gambell Environmental Services Man ager Ray Complex (520) 356

-3284 ngambell@asarco.com Joseph A. Wilhelm Manager ofMetallurgy Ray Complex

- Hayden Smelter (,?20) 356

- 3401 Duane M. Yantomo Divisional Environmental Manager Copper Opera ti ons - Tucson Office ( 520) 798-7745 Gary L. Lubers Manager

- Hayllen Concentrator

Ed 

### A. Riege Senior Environmental Engineer Hayden Smelter Larry 

### D. Hagy Envi r onmental Engineer Asarco Ray Complex Neil Nebeker Senior Metallurgical Engineer Ray Mine Mike Benevidas Casting

- Hayden Smelter Darry Cofer January 3 I, 2002

2BACKGROUND Asarco Incorporated ' s Ray Co111plex (hereafter "Asarco" or the "facility") and assudated operations in and near Hayden, Arizona include: • The Hayden Sme lter (EPA Identification Number AZD 008 397 127), a primary mineral proces sing facility (copper smelting); • TI1e Ray Mine (EPA ID 

### # 

### AZD 000 626 606), an open-p it copper mine located approximately 20 miles north ofllayden; • TI1e Hayden Concentrator (EPA ID # AZD 008 397 1 84), located near the Hayden Smelter ; • The Ray Concentrator, located adjacent to the Ray Mine; • Heap leach pad s, and associated barren and pregnant le ach storage and handling systems at the Ray Mine ; • A solvent extraction and copper electro

-winning (SXIEW) plant adjacent to tb e Ray Mine ; • An in

- pit ore crusher and a primary grinding miJI at tbe Ray Mine; and, • A seco ndary mill for crushing and grinding copper ore, located near the Hayden Concentrator. TI1e combined operations at the Ray Complex produce approximately 300 million pounds of copper a year . Asarco also operates a wastewater treatment plant at the Ray Complex . Asarco provides sewage treatment for the town ofHayden, and provides approximately 1,000 residents of Hayden and Winkleman, AZ with drinking water. According to Asarco's web pages and infonnational brochures (see Anachment #1 ofthis report), copper operation s at what became the Ray Complex bega ' n w ith the then-underground Ray Mine in 1 880. The Hayden Smelter was constructed by Asarco's predecessor in 1912 to process ore for the owners ofthe Ray mine. 

### In 1959, tbe Kennecott Copper Corporation , owners ofthe now open-pit Ray Mine, constructeQ their own smelter . Asarco purchased the Ray Mine operations in 19 86, and combined them with Asarco's newly

-modernized Hayden Smelter and Co nc entrator to fonn the Ray Complex. Effective November 11, 1999, Asarco Incorporated became a sub sidiary ofGrupo Mexico S.A de C . V. Additional infonnation on Asarco's history and chronologies for the Ray Complex can be found in Attachment #1 . Facility maps , covering the approximately 700 acres ofthe smelter area, fonn Attacbrnenr #2 .

3

### REGULATORY HISTORY Asarco submitted their initial Notification of Hazardous Waste Activity for the Hayder. Smelter in August of 1980. Records available to EPA indicate the last hazardous waste inspection of the Hayden Smelter (EPA lOti AZD 008 397 127) was conducted by the Arizona Department ofEnvironmental Quality (ADEQ) in November of 1994. Waste detennination violations were noted. Asarco bas subsequently returned to compliance . The Hayden Conceotrator (EPA lD 

### # AZD 008 397 184) was inspected by ADEQ 

### in September of 1998. No violations were noted (Att. #3). 

### In January of 1998 . the Department of Justi ce lodged two consent decrees to resolve alleged violations of the Clean Water Act (CWA) at the Ray 

### M jne and alleged violations of the CWA and the Resource Conservation and Recovery Act (RCRA) at Asarco's smelter facility (primarily lead) in East H e lena, Montana. A third consent decree was filed in May of 1999 resolving a Ueged RCRA and CW A violations at the East Helena smelter a nd alleged RCRA violations at Asarco's smelting and recycling faciliti es 

### in El Paso, Corpus Christ i , a nd Amarillo. TX (all Att. #4). Further infonnation can be found on page 1 of Asarco's subm ittal to EPA (Att . #10) . _ Penalties and_injunctive relief claims were estimated to total $56.3 million. Among other activities requjrcd under the consent decrees, Asarco agreed to: ".. .in stitllle improved materials screening and managemeutprocedures at each of its

four smelters nationwid e... "and; "... impleme11t an en han ced corporate-wide e nvironmental management and compliance auditing system at ASARCO's operating domesticfacilities . " (Att. #4). The focus of this investigation was not to assess Asarco 's compliance with the activities and schedules detailed 

### in the consent decrees 

### and related settlements. Asarco reported they were about mid-way through their consent decree schedule, and were preparing for an internal audit that was schedu led for October of2000. Some activities and procedures required by the consent decrees, however, had already been implemented at**tt: ~**  Hayden Smelter and thu s were observed or reviewed during this investig ation. For exampl e. Asarco's "Procedure for Pre-Acceptance Review and Verification Upon Receipt of Secondary Materials at Asarco's Operating Smelting Facilities" (see the first of the two quotes above) was already part of

### the ongoing operations at the Hayden Smelter (Att. #5 ) . We also briefly observed some ofthe construction activities at the Ray Mine which were conducted in response to the CW A consent decree . 

### INVESTIGATION From August 14,2000 through August 17,2000, a RCRA Compliance Evaluation 4lnspection (CEI) was conducted by inspectors from the United States Environmental Protection Agency (U.S . EPA) . The purpose ofthis inspection was to detennine the facility's compliance with applicable federal environmental statutes and regulations, and in particular the Resource Conservation and Recovery Act (RCRA), as ame nded , the regulations provided in the**Cou~** of Federal Regulations (CFR) T itl e 40, Parts 26 1

- 265, 2 68,270, and 279 , and Arizona's autho r ized hazardous waste program j · n the Arizooa Revised Statutes (ARS) Title 49 and the Arizona Administrative Code (AAC) Title 18, Chapter 

### 8, Article 2. A

s arco reponed generating approximately 14,739 pounds of hazardous waste in their 1999 Faci li ty Annual Report (FAR), including 12 ,285 pounds of •·...spent vacuum truck hoses , gloves and personal pr o tective equipment characteristically hazardous for lead and chrome . . . " (An. #6 , page 

### 3 of8). Although tht; 

### 1 999 total wou ld average less than 600 kilograms of hazardous waste per calendar month, Asarco indicated they were a large-quantity generator of RCRA hazardou s waste s in the 1999 

### FAR (Att . #6 , page 2 of8) . A review ofUnifonn Hazardous Waste Manife s ts and discussions with Asarco representative s indicated Asarco occasionally generated greater than 1,000 kilograms of hazardous waste in a ca lendar month and was a large-quantity generator (see AAC Rl8-8- 2 62(A) and 40 CFR 

### § 262.34} , especially during smelter shutdowns and equipment rebui lding " campaigns" . Thus, Asarco was evaluated as a large-quantity generator during this investigation . On September 20, 2000, EPA collected samples of Asarco media and products and conduc ted preliminary screening using a portable x-ray fluore s cence (XRF) instrument (Att. #7) . The analy sis res ults and 

### XRF s creening data form Attachment 

### #8 . PROCESSES In May of2000, EPA requested Asarco, under**th~** provisions ofSection 3007(a) of RCRA , to provide information on their facilities' processes (An. #9). The process information provided below supp lements the process information provided in the facility' s July 14,2000 respon s e to EPA ' s 3007(a) information request (Att. 

### # 10). The addi ti onal information detailed below includes clarifications and additiona l proce s s infonnation obtained during and subsequent to the inspection . Based upon information gathered during the inspection, the Asarco process flowsheet s s ubmitted as the Appendix of their 3007(a) response (extracted into thi s report as Attachment #II) were modified t o reflect current operations. The revised process Oowsheets created by EPA form Attachment #12 ofthi s report . Ray 

### Mine: A s arco p a rtially owns the "Copper Basin Railway", which transports ground ore from the primary grinding mill at the Ray Mine to the secondary mills located near the Hayden 5

### Concentrator, and also transports sulfuric acid from the Hayden Smelter acid plant to acid storage tanks at the Ray Mine. 

### The 

### CoppCJ: Basin Railway coMects to the nationwide rail system via a rail spur 

### in Florence, AZ. Heap 

### Leach Pads: lncomin2 Material; Crushed oxide ore and low-grade sulfide ores; purchased sulfuric acid; sulfuric acid from the Hayden Sme\ter acid plant (see discussion below); sulfuric acid from the acid plant cone settler overflow (CSO) tank (see discussion below); barren leach solution from the SXJEW plant. Outgoin2 Material: Pregnant leach solutions to the SX!EW plant. Additional Process Information : (Supplements information 

### in Attachment# 10) . • Unloading . from the rail cars is only done at night , so workers can avoid the heat while wearing the protective suits tequircd for unloading the cars. Approximately 24 acid cars are unloaded each twelve-hour shin. • Inco ming purchased and produced sulfuric acid is air pumped into a 90,000 gallon storage tank The CSO is sepa rately stored in two 20,000 gallon tanks . 

### Heap Leach Regulatory lssues: I ssue 

### #1:

Details: Clarified acid from the acid plant gas cleaning system drum filter and CSO is sent to Asarco's heap leach pads for its acid value (pH approximately 

### 1.0) and also for its water value. This liquid is also characteristic for arsenic, cadmium, lead, and se lenium (see the CSO acid discussion in the Gas Cleaning System and the Sulfuric Acid Plant section and Att. #8). Is this practice in violation of any RCRA regulations?

Water and sulfuric acid are the primary ingredients used in 

### the heap leach solutions . Heap leaching i s beneficiation (40 CFR 

### § 261.4(b){7)). During use, the acid and water solution is sprayed onto a mound ("heap") ofore. The solution dis solves ("leaches") copper and other metals from the ore. Copper in the metals

- loaded ("pregnant") leach solution is then electro-plated onto copper anodes ("electro-winning"). After electro-winning, the spent pregnant leach ("barren leach") is 

### returned to the heap leach motmd to dissolve more met a ls. Asarco is located in an arid or desert area of Arizona, and the capture of water from the acids, mine infiltration, equipment rinsing, rainwater runoff containment areas, etc. was common and economically necessary . The captured water is typically reused in the heap leach solution or 6in the concent rdlor units . This copper ore contain s s ulf ates. Exothermic s ulfur reactions provide much ofthe heat used in the furnace and converters, and**sulfur~laden** gases from the smelter are coltected 

### ty air pollution control devices and used to produce su lfuri c acid. Asarco uses some of the sulfuric ac id they produce 

### in their heap leach solutions, but significant quantities of sulfuric acid arc sold as product. Asarco reported that the acid they produce is often of such high quality, and has sucb a high market value as a commodity, th a t they sell the sulfuric ac id produced in their acid plants an d purchase a lesser quality sulfuric acid from the open market for u se on the heap leach . Particles from the smelter exhaust can be carried over into the sulfuric acid production vessels. The sulfuric ac id process tanks are then "blown down.. to remove the paniculates. The particles are removed from the resulting acid plant blowdown liquids by a series ofclarifiers , thickener tanks , filter presses. and the cone set tler. 

### "Acid plant blowdown slurry/sludge resulting from the thickening of blowdown slurry from primary copper. production " was formeFiy listed as hazardous waste number K064 . On October 20, 1999 (64 FR 56470) EPA removed the listing for K064, after previously explaining that the s e wastes can be effectively regulated if they exhibit a hazardou s characteristic (63 FR 28600). 1 The clarified liquid 

### that overflows from the cone settler (both the cone settler tank and the liquid overflow are referred to as .. CSO" by Asarco), is variously referred to as "weak acid" , " blowdown", 

### ''weak acid blowdown" and "clarified acid" by other Arizona copper smelters . This "weak acid" is a strong corrosive with a pH ofapproximately 0 . 3

- 1.0 . (Sulfuri c acid from the gas scrubbing tower is 

### weakened by the absorption of water vapor from the S0 2 gas , while tbe sulfuric acid sold as a product is 

### strengthened by the absorption of 

## so) gas . ) Analysis and Interpretation : The reuse of the water at Asarco appears to be legitimate. The water was typically not characteris tic , was not being stored in impoundments, and was being reu sed for 

### its water value . Materials are not solid waste when recycled 

### by being reused as ingredients in an industrial process to make a product or as effective substitutes for commercial products (40 CFR § 26 1 .2(e)( l)). Distinct components of the water are not recovered as separate e nd products (i . e. it is not reclaimed). See 40 CFR 

### § 261 . 1 (c }(5)(i)).

. As noted , the CSO weak acid does display the hazardous waste charactcnstics . Asarco stated that: 

### "[Tjhe gas cleaning systems are mineralprocessingjacilities because the materials resulting/rom operation of this equip ment gain th eir chemical qualit.y primarily from constituents originating in the ore and copper concentrate. Th e acidplant, however, is not

1 40 CFR 

### § 261.4(b)(7)(ii) lists certain solid wastes from the processing of ores and minerals (i . e . "mineral processing wastes") that are not hazardous wastes. Although residues from the treatment of acid plant blowdown (calcium su lfate wastewater treatment plant sludge from primary copper processing) are included in the li st (40 CFR 

### § 261.4(b)(7)(ii)(H)), acid plant blowdown is not. 7considered a mineralprocessingfacility. "(Page 16, Alt . #10) Asarco notes EPA's previous conclusion, discussed in the background documents incorporated into the LOR Phase IV docket, that acid plants are not uniquely associated to s melting. EPA reiterated this point in the LOR Phase IV final rule, defining "uniquely associated" 1 and stating that the acid plant blowdown at copper smelters is subject to the RCRA hazardous waste regulations if 

### it exhibits a hazardou s characteristic (63 FR 28600). The acid plant blowdown used on the heap leach is characteristically hazardous. The clarified acid from the acid plant blowdown is used on 

### an unlined heap leach , which may be a u se constituting disposal. Materials used in a manner constituting disposal arc so lid wastes even if they are legitimately recycled (40 CFR 

### § 261.2(e)(2)(i) and Column I ofTable 

### I in 40 CFR 

### § 26 

### J . 2) . J As noted, the clarified acid used on the heap le ach is characteristically hazardous . Hazardous waste s that are re cycled are •'recyclable materials" (

### 40 CFR 

### § 26 

### f . 6(a)(l)) . Re c yclable materials used in a manner constitut ing disposal are requ ired to comply with 40 CFR § 266 .20 . 40 CFR 

### § 266.20 requires the recyclable material to meet 

### the applicable Land Disposal Restrictions prior to placement on the land . The characteristically

- hazardous clarified acid does not meet the treatment standard s for the toxic metals . Asarco s tated, however, that the use of the weak acid on the heap leach is legitimate because "...theprovisions of 

### 40 C.F.R. 26 1.2(e)(J )(ii) and tire definition of solid waste und er 

### 40 C.F.R. 261.2(c)(J)(i0 'allow for placement on the land that does not cons titute disposal 

## if that is th e manner of th eir ordinary use. '"(page 20, Att. 

### # 1 0) . Additionally , Asarco noted ADEQ 's interpretation ofthe 1997 military munitions rule (62 FR 6628) : "... us e of a product for 

### its intendedpurpose, even when th e use of the product results in deposition on the land, does not consti tut e aiscard, 'a nd , th erefore, the material is not necessarily a solid waste. "' (page 20, Att . #10). Actually, 40 CFR 

### § 261.2(c)(l)(ii) states that: "... co mmercial ch emicalproducts listed in§ 26/.33 are no t solid wastes 

### if th ey are applied to tire /anti and that i s their ordinary manner of use. " While suJfuric ac id is a commercial chemical product, it is not li sted in 40 CFR 

### § 

### 26 I . 33 . The Munitions Rule**an~** previous EPA letters have recognized that commercial chemical

2 " ... any wastefi·om ancillary operation s are not " uniquely associated" b eca use they are not properly viewed as b e ing ' from" mining or mineralprocessing . In evaluating wastes from no11-ancil/ary operations, one must consider th e extent to which the waste originates or derives from pr ocesses that serve to remov e mineral values from the ground, conce11trate or o therwise enhance their characteris tics or remove impurities, and the extent to which the mineral recoveryprocess imparts its chemical characteristics to the waste. " (63 FR 28591) 1 Unlike so m e of the recyclable materials discussed below, the clarified ac id is not a listed hazardous waste and is not reclaimed (i .e isn ' t part of a furnace feedstock and is not retorted) . The weak acid from the acid plant blowdown meets the definition of"sludge[s]" in 40 CFR 

### § 260 . 10, because the acid plant is connected to 

### the smelter' s air pollution control devices . 

### It also can be cons idered a •'by-product., as defined in 40 CFR 

### § 261.1(c)(3). The sulfuric acid produced for sale by the acid plant is a ..co-product", not a so lid waste s ludge or by

-product (50 FR625) . 8products may still be legitimate ly recycled when they are app lied to the land and th at is their ordinary manner of use, even i f the chemical products are not speci fic all y listed in 40 CFR § 261.33 , , Asarco must purchase or produce sulfuric acid, a c hemical product, for use in the heap leach solu tion . The clarified sulfuric acid replaces some ofthe acid product that is ordinarily used. Thus , the clarified acid can be considered a "commercial**product' ~**  that is nonnally "applied to the land" during use on tbe heap leach . Wben legitimately recycled into the heap l each solution, the clarified ac id is not a solid waste (40 CFR 

### § 26 1.2(c )( l 

### )(ii)).



# - The question now becomes: Is the use of the characteristica lly -hazardous clarified acid from the aci d plant blowdown in the heap leach solution legitimate recycling? G iven its strong acid value, the "weak" acid blowdown appears to be an effective replacement for some ofthe sulfuric 

### acid normally used in the heap leach solut ion . Asarco stated that " ... The 

### pH of the solulion is 1.0 1naking it a s uitable commerci alproduct substilute for Ihe normal raffinale, which has a pH of approximately 2.0 ... "(Page 20, An . #I 0) . As discussed in the Revert Scree'ning Area · and Revert Handling section, one criterion in determining the legitimacy ofre cycl ing 

## i sw hether there are ''toxics along for the**ride" ~**  Although some of the lead in the weak acid may eventually be recovered as ·a lead concentmte after electro-winning, the c harac teristi call y-h igh l eve ls of cadmi um, selenium, and arsenic are non-contributing hazardous constituents .$ Situations likely to be deemed s ham recycling would involve low amounts of recoverable material plus the presence of non-contributing hazardous constituents in the waste, " ... particularly hazar dous constituenl s not olhenvise present in the normal feed'itock of the process... " (63 FR 28587). The clarified acid has large amounts of recoverable material (su lfuric acid). The normal feedstocks ofthe heap leaching process are water, acid, and ore. A detailed review ofthe processes indicates that Asarco wa s correct in determining the weak acid derive s all ofits acid value and toxic metals from the sulfates and m eta ls originally in the ore (Page 16 , Att. #10) . We did not find any other sources of material s that · would account for the hazardous characteristics (either toxi c metals or corros ivity) ofthe acid. Thus, the usc of the clarified acid in the heap leach soluti o n would not introduce hazardous cons ti tue nts not already present in the feedstock The acid in the heap le ach solution (including the clarified acid portion) leaches the to Xlc metals present 

### in the ore along with the copper. The use ofthe clarified acid removes toxic metals from the heap leach. Thus, the clarified acid portion will gain toxic metals, not dispose of them . Although the toxic metals are "along for the ride", the weak acid is used on the heap leach primarily to leach copper, not as sham means of disposing oftoxi c metals. Thus, the usc of ac id

• See 53 FR 522 (1/8/88), 52 FR 17013 (5/6/87), and 50 FR 638 ( 1/4/85) for examp les of recycling legitimacy criteria. The clarified acid is not speculati vely accumulated . 5 We believe that the cadmium, selenium, and arsenic are also removed from the electro-winning process in the lead concentrate, but because this line of inquiry was developed after our inspections at the copper smelters, we do not hav e confirma tion from the facilities . 9in the heap le ach is not use co n stirut ing disposal, and the clarified acid from the acid plant blowdown used in the heap leach solution is being legitima tely recycled . 

### Solvent Extraction and Copper Electro-Winning (SXIEW) Plant: Incoming Material : Copper starter sheets from Asarco's refinery in Amarillo , TX; lead anodes; pregnant leach solution . Outgoing Material :**~opper** cathodes (at 99 . 999% copper); barren leach; used lead anodes; lead flake ; lead sulfate residue. Additional Proce ss Information : (Supplements information in**Attac~ment** 

### #I 0) • The SX!EW Plant generates "lead flake" and lead su lfate residues . The lead flake is sh ipped to Asarco's East Helena lead smelter. • A printout from Asarco's intranet Material Safety Data Sheet (MSDS) system for lead flake and le ad sulfate indicates the lead Oake contains 10

- 50% lead, and would be a hazardous waste (0008) if discarded (Att . #13). • Spent lead anodes are rehlmed to the vendor that provides the new anodes . SX!EW Plant Regulatory**ssues: ~**  A 20-yard bin marked as containing "beads . only" actually held lead flake . Asarco repre senta tive s stated that all outgoing bins are properly placarded before they are transported to East Helena. The SX!EW Plant receives pregnant leach s olutions from the Heap Leach . See the discus sion on the use ofCSO weak acid in the Heap Leach section above. 

### Hayden Mills : The mills were constructed in 191\. Copper ore from the Ray Mine is unloaded into a crusher (for secondary and tertiary crushing with cone crushers) and then passes through four rod mills and four ball mills . The milled ore is then fed into the flotation series in the Concentrator. Incoming Material : 10Approximately 30,000 ton s ofore per day (300 ore cars a t 100 tons/car) brought in by rail (s ee Attachment 

### 1143, photo J); oversized s lag ; water. Outeoing Materi a l : Slurried ore to concentrator; approximately 

### 50 gallons per minute of water flow s to tailings impoundment via a gravity ditch. Additional Process Infonnation: (Supp lements infonnation in Attachment # 10) • The ore crus her area is s hown in photos 

### 3-6 . • Mill crushing and grinding operations are shown in photos 

### 7-8. • The crushed and ground ore is conveyed to the concentrator via overhead conveyer belts (photos 

### 9-1 0). • EPA samp l es collected from under the ore conveyer belts did not display any of the Toxic ity Characteristics (Att._ #8). • Approximately 30,000 ton s offinely crushed ore (a one-day s uppl y) i s stored in the fine ore building .

" H igh chrome" s hot ball s, bought u sed from cement plants , a re used in 

### the ball mill s . Mills Regulatory Iss ue s: None . Hayden Concentrator: Incoming Material : Fihely ground ore; c rushed refractory brick (approximately 15% copper); fresh water; flotation reagents. Outgoing Material : Copper concentrate to the bedding plant; tailings (water and non -copper so lid s) to the tailings impoundment ; solids from the gravity bins to the filter plant. Additional Process Jnfoonation: (Supplements infonnation in Attachment #10) • The three -s tory Concentrator has ten froth flotation rows, with each row consisting ofa serie s of tanks ("banks") . Each row has eight ''rou gher " banks (about 15% copper, one scavenger bank, one fina l cleaner (25 -3 0% copper) (photos I I -12). The co ncentrate goes 11through a re-grind mill between flotation banks . • The froth flotation reagents jnclude milk oflime , pine oil , alcohol , and potassium amy l xanthate . • Liquids and solids that leak or spill from the flotation banks and wash down water flow to channel s below the Concentrator {the ''subway" flows to the "Grand Canyon " or "Salt ruver Canyon") (photo 13). Overflow from the "Canyons " is pumped through a filter plant and thickener at the concentrator and goes back into.

### the flotation circuits . • Copper recovery in the Concentrator averages about 86% , and is measured every fi ve minutes or s o by the Head Operator. • The tailings are normally pumped to the top of the tailings impoundments , but can gravity flow to the toe oftailings during upsets . • Asarco used to operate a molybdenum recovery circuit at the Concentrator. The current market price of molybdenum, however, is about one-half of what Asarco estimates 

### it costs to produce and handle at the Concentrator, so the circuit remains idle. • Liquids discharged from the Concentrator had puddled on the roadway (photos 14-1 5) . Further inspection , however. showed it was condensate {clean water) from the water coolers and air conditioners . • Approximately 300-400 tons of a dark material was piled near the roadway {photos 16

- 17) . Facility representatives stated that solids are generated during upset conditions, when solids from the ..9-bin pump tails" s ettle in gravity bins . The solids arc collected with a long-reach excavatoT and the resulting "low-grade concentrate" Lc; moved within two weeks to the filter plant, and then to the bedding plant. EPA samples collected from under the fence line shown to the left 

### in photo 

### t 7 did not display any of the Toxicity Characteristics (Att . #8). Concentrator Regulato!)' Iss ues : See Brick; Revert Screening Area and Reverts Handling . 

### Bedding Plant Area, Delumper, and Dryer: Incoming Material: According to Asarco ' s submittal (see page 6 ofAttachment #10) each 6,000 ton bin holds about 5,200-5,.300 tons concentrate, 500 tons silica flux {occasionally includes used s ilica beads and quartz rock from acid plant), and about 200

- 300 tons of other materials and byproducts . 

### 12The other materials and byproduct s include: crushed reverts and matte, dusts removed from flash furnace and converter off -gases (acid plant dust, converter hood dust , spray chamber dust and flash furnace filter cake); Cottrell and secondary hood baghouse du!'t, dust from the concentrate dryer baghou se; filter rock from the fluidized bed concentrate dryer; delumper reject s from the wet screens. Out2oing Material: Furnace feed; delumper rejects 6 ; filter rock; used baghous e bags; fluidi zed b ed dryer offgas; water to evaporation . Additional Process Information : (Supplements information in Attachment #10) • TI1e concentrate , primarily from the Ray, Hayden, and Mission concentrators, is delivered in bottom dump rail cars or trucks (photo 18) and passes through the reclaim hopper (photos 19-22). An auger is used to collect six assay samples from each rail car. Asarco normally bas about 20,000 to ns of concentrate on hand. At tlle time of inspection, Asarco estimated they bad approximately I 00,000 ton s of concentrate on hand (photos 23·27). Much of the additional su pply was identified as Mission concentrate (photos 28-29). • The Bedding Plant has four 6,000-ton beds in concrete walled and floored bunkers (photos 30·32). • The Hayden smelter uses 2,500 tons/day of concentrate, so each 6,000 ton bin is smelted in about 2.1 to 2.3 days . • The concentrate is inventoried monthly . • The "Ray and Mission concentrate" contains approximately 27% copper (Att. #14). The Mission concentrate displays the Toxicity Characteristic for lead (6 mg/L TCLP, Att . #8). • Th e bags from the Dryer baghou se contain approximately 17% copper, and di splay the Toxicity Characteris ti cs for cadmium and lead (Att. #15). Beddin g Plant Area Regulatory Issues : · See discussions in: Gas C leaning and S ulfuri c Acid Plant; Filter Pl ant ; Revert Screening Area and Reverts Handling; Brick ; CP-1 Sump and Impoundment.

" After drying in the fluidized bed dryer, the smelter feed is raised into the s melter by air pressure . Feed particles too large to 

### be blown into the smelter ("delumper rejects") are ground to a - 10 mes h , about the size ofbeach sand, and then returned to the bedding plant 13

### Oxygen (0 1 ) 

### Plant: Incoming**Material ~**  

### Air; water; electricity . Outgoing Material : 500 tons oxygen per day to the Jnco flash furnace; nitrogen vented to atmosphere; maintenance waste s. Additional Process Jnfonnation : (Supplements information in Attachment 

### #10) • The Oxygen Plant underwent a major rebuild in 

### 19.83. • Can also make liquid 

### 0 1 for backup storage or sale. 

### Q 1 Plant Regulatory l ss ues : 

## -**~** A co ntainer of used oil was marked as containing ••waste oil". The container WdS placed under a Used Oil sign. The label was promptly corrected (Att. 34). 

### Inco Flash Furnace : According to Asarco's s ubmittal to EPA : "Asarea's Hayden smelter proc esses copper concentrate into copper anodes using an Inca flashfumace, five Pierce Smith converter vessels. two anode furnaces and two anode castiflg wheels." (page 5, Att . #10). Incoming Material : Furnace feed fro m the bedding plant; oxygen from the oxygen plant; naturnl gas; s1lic a; bone ash. Outgoing Material : Matte; slag; used furnace refractory brick; lander brick; lnco flash furnace off -g as; fugitive gases; approximately 200 tons/day flue dust , other reverts. Additional Process lnfonnatjon ; (Supplements information in Attachment #10) • The furnace chambers are lined with silica flux_, purchased from a nearby mine . 

### 14• Bone ash, purchased from South America, is used as a relea s ing agent in the launders, spoons, ladles, etc. • The smelter operates continually, with a shut down occurring once every two years. • The s melter 's s tack is 1000 feet tall. • Bricks from the launders were noted in the converter ai sle ncar the sus pended bumping block, which is made of 30 ton s of copper. • The matte is tapped three times per hour, into 200 cubic foot ladles. Slag is tapped once per hour into a 600 cubic foot ladle. Inco Flasb Furnace RegulatorY I ss ues: The outlets of the flu e dust bins arc nonnally sea led w ith s ilica . During inspection, Asarco rep r esentatives noted two bins that were sca led with flue dust, not silica (photo 33). The bins were promptly scaled properly (photo 34). See discussion s in: Gas C leaning and Sulfwic Acid Plant; Filter Plant ; Revert Screenin g Area and Reverts Handling; Brick; CP- 1 Sump and Impoundment. Converters : Asarco operates five Pierce-Smith converters. Incoming Material : Matte from the furnace , si lica; 3-inch ceramic saddles from the acid plant for use as silica; reverts for use as cold dope; used baghouse bags ; bli ster copper .bars; "foul" anodes. Outgoing Material: Bli ster copper, co nverte r slag; reverts ; used brick ; off-gas particu lates (converter dusts); ofT -g ases to the gas cleaning sys tem and acid plant; converter s lag . Additional Pr ocess Information : (Supplements information in Attachment #10) • The converter aisle, with ladles, skulls and revert s material, i s s hown in photos 35- 38 and 41-4 2. Bunker #1, holding mainly cold dope reverts, is sho wn in photos .39-40. • The matte contains about 65% copper, 15% sulfur, 20% iron . • Each converte r receives about 150 tons/day matte , and produce s about 100 tons of blister copper. 15• Approximately 30 ladles of converter slag per day go into the furnace . • Asarco's MSDS for matte and slag she ll shows they contain approximately 30-40% copper, 1-3% lead (Att. # 16). • Asarco analysis of matte from Asarco's El P.aso facility shows the matte displays the Toxicity Characteristics for lead at 47.5 ppm TCLP (Att. #17). • The converters receive about 10 baghouse bags per week . • Each 150-ton converter charge contains about five ladles of cold revert s. Converter Regulatory Issues: See discussions in : Gas Cleaning and Sulfuric Acid Plant; Revert Screening Area and Reverts Handling; Brick. Anode Barrel Furnace, Remelt Vessel, and Casting Wheel : Asarco operates two Fuller anode furnaces and fluid bed dryers , and two anode casti ng wheels (photos 43-47) . incoming Material: Blister copper from converters; blister bars from Mexico; natural gas; steam ; barite s lurry used as a mold release; contact cooling water. Outgoing Material: Anode copper; anode s lag (to the converters); used refrdctory brick; reverts from minor splas hes and spills; reject anodes (to the converters); off-gases (to atmosphere); contact cooling water (r eused at the casting wheel). Additional Process Infonnation: (Supplements infonnation in Attachment #10) • Each o f the two anode furnaces receives a 300 ton charge of blister copper. • About 25 tons per blow of anode skimmer slag goes to the converter. 

# . • The anode casting wheels are made of copper, and cast about 60 tons/hour ofanodes (photos 44-46) . • The cast anode co ntains about 825 pounds of99.4% copper (photo 47) . The anodes go to the Asarco refinery in Amarillo, Texas.

1637 . Training Plan , undated , circ a 1997 . 38. Arizona Department of Health Services Environmental Laboratory Licens es for J/20 199- 1/20 / 00 and 5/22/00

- 5/22101. 39. Asarco Analys is and hazardous waste de tenninations for : Ace Pipe Cleaning PPE Used gloves Used work boots 40. Weekly Container Inspection Log for Plastic Hose RolloffBin dated 2/15/00 though 8/14/00. 41. Selected Unifonn Hazardous Waste Manifests. 42. MineraJ Pro cess ing M aterial s Inventory as submitted to ADEQ dated 5/3 1/00. 4 3. 1nspe c tion photograph s.



### 4420. Asarco Assay/Analysis for Acid Plant Filters (mist eliminators) dated 5/6/97. 21. Asarco Assay/ Analysi s for 

### WTP drum .filter cake dated 7/12198. 22 . Asarco Assay/ Analysis for WTP plate filter cake dated 7/12198 . 23 . Asarco Assay/Analysis for filter cake plastic and filter plant tank rubber dated I 0/3/96 and associated Laidlaw Environmental Services material profile. 24. Asarco Assay/Analysis for: Converter cyclone dust dated 7/30/98; Delumper reject dated 1217/98 ; Converter hood dust dated 7/3Q/98; Converter spray chamber dust dated 7/1 0/98; "Revert in aisle" dated 7/9/98 ; Ace baghouse bags dated 7/21/00; Filter rock dated 7 I I 0/98. Crucibles and cupels dated 717/00 ; Silica blasting abrasive dated 7/14/00. 25. Material Sa fety Data Sheets for refractory bricks . 26. Asarco Assay/Analysis for "N 3 Brick Converter'' dated 6/ 4/97 and anode brick dated 4/ 15/98 . 2 7 . Material Safety Data Sheet for precious metal s used refractory brick dated 3/20/97 . 28 . Unifonn Hazardous Waste Manifest for precious metals used refractory brick dated 8/2/00 . 29. Asarco Assay/Analysis and handling records for co ncrete s ump sediment removal dated 211 I/99 through 1/21/00. 30. Asarco Analysis for plastic vacuum hose dated 9/17/98 . 3 I . Material Safety Data S heets for Nalco floc culan ts dated 2117/97 and 2/23/99. 32. Kennecott tracking sheet for Moberg algicide dated 8/17/00 . 33 . Asarco let ter t9 EPA with attachments and photos dated 8/23/00 . 34 . Asarco photos taken 8/16/00. 35. Asarco Hazard Recognitionffraining card dated 8/15/00 . 36 . Example of Asarco R.CRA hazardous waste training materials .

. 43

### AIT ACHMENTS I . 

### Facility brochure and selected web s ite page s. 2. Faci lity maps. 3 . 

### ADEQ Report for 

### the Septem ber 22, 

### I998 inspection. 4 . 63 FR 8473, dated 2/19/98, 64 FR 23858-9, dated 5/9/99, and as sociated press releases . 

### 5. Procedure for Pre-Acceptance Review and Verification Upon Receipt of Secondary Material s at A s arco 's Operating Smelting facilities dated 12/l 6/98. 6 . l999 facility Annual Report. (FAR) . 7. EPA field Samp ling Plan dated 9/ 15/00. 8 . EPA Region 9 Laboratory- Ri chmond, CA : Summari es o f Ana lytical Resul ts and 

### XRF Preliminary Screening D ata . 

### 9 . EPA 3007(a) Informati on requ est dated 5111/00; A

sarco letter to EPA dated 5/19/00; 

### EPA e-mail to A sar co date d 6/6/00 ; EPA letter to A s arco dated 6/8/00. 10 . Asarco' s 7/14/00 s ubmittal( s) in res ponse to the 3007(a) request . I I . 

### Asarco pro c ess fl ows beets dated 717/00 . 12. EPA 's re vi sed pr ocess flow sbeets. 

### 13 . Material Sa fety Data Sheet for lead flake , lead sulfate, EW plant residue dated 9/1/93 . 14 . Material Saf ety Data Sheet for Mi ss ion and Ray Concentrate dated 7/2/96 . 15. A sa rco Assay/ Analys is for silica blasting abrasive, dryer baghouse , and benn dirt date d 7/00. 16 . Material Safety Data Sheet for matte and slag shell dated 5/ 19 /95. I 

### 7 . A s arco Assay/Analysis for El Pas o matte dated 8/13/98 . 18 . Asarco As s ay/Analysis for Acid Plant used silica beads and quartz ro ck (ceramic sadd les and V20 5 fine s ) date d 6- 7 /00 . • 19 . A sarco Assay/Analysis fo r polypropy lene saddles dated 8/98 . 

### 42

### AAC Rl8-8-262(A) 

### and 40 CFR 

### § 

### 262.3 4(a )(4) The training plan did not describe the type and amount of botb introductory and continuing ttaining of each employee with duties related to hazardous waste management, as required by 

### 40 CFR 

### § 265.J6(d)(3). The violation bas been correc ted .



### 41

### POTENTIAL VIOLATIONS AAC, Title 18 , Chapter 8, Article 2, Section RlS-8-262, states in pertinent part: 

# . All of40 CFR 262 and the acc ompanying appendices, as amended as of July 1, 1999... are incorporated by reference and modified by the following subsections c:>fRJS-8-262 ... 

### ARS , Chapter 49, Artfcle 7, Section 49-802 , states In pertinent part:

.. .40 

### Code ofFederal Regulations part 279, as amended on January L, 1997 , is adopted by reference. AAC Rl8-.8-262(A) and 40 CFR 

### § 262 . 34(a)( 

### l)(i)

AAC RI8-8-262(A) and 40 CFR 

### § 262.34(a)(4) AAC Rl8-8-262(A) and 40 CFR 

### § 262 . 34(a)(4)

ARS49-802 and 40 CFR 

### § 279.22(c)( 

### I)

AAC Rl&-8 -2 62(A) and 40 CFR 

### § 262.34(a)(4) A roll-off bin ofhazardous waste in the Ace Pipe Cleaning yard and a 55-gallon drum by the Environmental Engineering Office were not stored closed, except when necessary to add or remove waste, as required by 40 CFR 

### § 265.17 3(a) The violations have been corrected The Ace Pipe C leaning storage area were not equipped with fire extinguishers, as required by 40 CFR 

### § 265 .32 (c) . The violation has been correc ted. The fire extinguisher in the 90-day accumulation area was not tested or inspected to assure its proper operation in an emergency, as required by 40 CFR 

### § 265.33 . The violation has been corrected A 500

- gallon u sed oil 

### tank in tbe Ace Pipe Cleaning yard, a 500-gallon used oil collection tank near the Truck Shops, the 

### fill pipe s to the oil tank at the oi l-water separator , a 55-gallon drum holding used oil and used oil filters near the truck s hop, a 

### I 50

- gallon container at tbe locomotive shop, two 55-gallon drums of ustd oil at the Oxygen Plant, and a 5-gallon bucket ofu sed oil . outside of the Tool Room all were not labeled or marked clearly with the words "Used Oil." The violations have been corrected. The contingency plan did not list the name addresses ofall persons qua lified to act as emergency coordinators, as required by 40 CFR 

### § 265 . 52(d). The violation ha s been corrected. 40used work boots arsenic, cadmium, chromi u:n waste paint F003, DOOI parts cleaner {prior to 2000) D039 filter cake weighing dishes cadmium, lead drilling grease lead Used clothing**an~** personal protective equipment are collected in special lockers to prevent exposure to dust {photo 120). Accord in g to Asarco representatives , the Safety-Klecn parts cleaners used on site s ince 1999 are no t hazardous wastes. Other materials determined not to be hazardous wastes include : filters from the furnace air and r oom cond itioners; spent respirator cartridges (pass TCLP); fluorescent lights; sewage s ludge {pass TCLP, are conveyed to off-s ite sewers by the "honey wagon") ; and used oil (has always been o n- specificat ion) . Biohazard wastes from the medical clinic are shipped to Stericycle as medical waste . Supersacks containing new vanadiwn pentoxide arc reportedly rendered RCRA-empty by shaking and are then sent to 

### the so lid was te landfill. Other Reco rd s: Weekly inspection records for the 90-day storage area were complete from September 1999 to August 2000 . 90-day storage area records dating back to 1994 were available for review . Examples of the satellite accumulation area inspection records form Attachment #40. Biennial Reports and Facility Annuai .Reports dating back to the 1980's were avai lab le for review. Un if orm Hazardous Waste Manifests dated back to September of 1999 

### were reviewed (Att. #4 1 ) . No deficiencies were noted .

39

### Recordkeeping and Reporting Training : Initial Hazard Recognition training was provided by Jody Schwing l e, ofthe Safety Office (Att. #35) . Asarco has developed detailed RCRA hazardous waste training, including RCRA training materials and videotapes prepared by Asarco's corporate offices and facility-specifi c training prepared by the Ray Complex (see example in Attachment #36). According to Asarco representatives, updated RCRA trainin&requirements were instituted in 1999. Under the new schedule, every employee will receive an initial four hours of tra ining, followed by a two-hour annual**refresb~r .**  During the August inspection, approximately 700 ofAsarco 's 1400-1500 employees had completed the 2000 aMual refresher. Tbese training requirements, however, were not reflected in Asarco's Training Plan (Att . #37) . The plan bas since been modified to "re flect the current training and recordkeeping requirements (Att. #33) . Fire training is also provide<ko Asarco pers onnel. According to Asarco repre sentative s, they have open bum pennits which specify what can be burned during the fire training exercises. Wa ste petroleum products such as used oil and solvents, and empty hazardous materials containers, tires, wire, etc. are not burned. Contingency Plan : The Contingency Plan, dated 8/11/00, d id no t include the home addresses of the primary emergency responders or a list ofemergency equipment. The. Contingency Plan was subsequently modified (Att. #33). · Waste Analysis: Asarco's Hayden Laboratory is lic ensed by the Arizona Department of Health Services to perform a variety of hazardous waste analysis, including the Toxicity Characteristics leaching Procedure (TC:LP) (Att . #38). Asarco conducted a number ofhazardous waste determinations, particularly in 1996 ·and 1998 , and appears to have thoroughly characterized the potentially hazardou s materials produced at the Ray Complex. In addition to the materials and wastes previously discussed 

### in this report, Asar..;o analysis results indicates the following materials are hazardous wastes (see Att. #39):



### MATERIAL 

### HW CHARACTERISTIC laboratory assay c ru cibles and cupels lead at 3000 ppm u sed personal protective equipment used by the Ace Pipe lead Cleaning employees u sed g loves cadmium, lead 

### 38**wa ~**  last punched in 1998 . A s arco representatives promptly had the extinguisher inspected (photo I 0 3 ) . The 90-day area did not have a. n eyewash station . An eyewash unit has been added (see photo in Attachment #33) . Environmental Engineering Accumulation: 

### The lid on a 55-gallon drum, about 3/4 full of spray paint cans, could not be closed (photos l 04-1 05) . The lid was promptly fixed (see photo I06 and Att . #34). Ace Pipe Cleaning. 

### Inc. Yard: As noted, Ace Pipe Cleaning (Kansas City, MO) uses vacuum trucks to collect metal bearing dus ts and s ludges. The used plastic flex hoses exceed the Toxicity Characteristics for cadmium and lead (Att . #30). The bin holding the hoses was not securely closed (photo 107), there was no fire extinguisher near the hazardous waste accumulation area, and an approximately 500-gallon used oil tank was not marked with the words .. Us ed Oil" (photo I 08) . The bin was promptly closed, and the tank, which was about !12 full , was marked with the words "Used Oil" (An . #34) . A fire extinguisher was subs equently installed (Att . #33) . Water Filter Plant Control Room : Thi s area contained used personal protective equipment (see Waste Analysis , below). No violations were noted. Empty Container and Used Oil Storage Yard : Constructed in 1994, this area has a sloped and bermed concrete pad with a concrete-lined blind sump . Used oil containers are serviced by Mesa Oil, and were stored on containment pallets . The area is also used to store spill equipment. See photos 108-110 . · Oil Collection Tank and Oil- Water Separator: A 500-gallon u sed oil collection tank near the Truck Shops was not marked with the words .. Used Oil" (photo l 1 1 ). The tank was promptly labeled {Photo 112). Also near the Truck Shops wa s an oil-water separator (photos 113-115) that serves the maintenance areas. The separator sends oily wate r through a s and

-trap filter. The water goes to CP-1 , and the oil is collected in a tank. The fill pipe s to the oil-water separator oil tank were not marked with the words " Used Oil ' ' (photo 115), and one oftwo 55-gallon drums holding used oil and used oil filters was not marked as containing used oil (photo 116) . The drum was promptly labeled, and oil sump tank and fill pipes were subsequently marked with the words .. Used Oil'' (photo s 117-118 and Att. #33) . Ux::omotive Shop : Maintenance of Asarco ' s diesel/electric locomotives is directed by Hugh Alexander, Main Manager. According to Asarco repres entatives, the locomotive oil filters are ROt teme plated. One uwnarked container, with a capacity of approximate ly 150 gallons, was about half full ofused oil (photos 119) . Auto Shop: The auto shop is managed by Mike Fialla, shop foreman . No violations were noted . Landfill : The solid waste landfill was briefly toured. No hazardous wastes were noted . 

### 37Kennecott Smelter: Additional Process Jnfonn ation : (Supplements information in Attachment 

### # I 0) • The s melter formerly operated by Kennecott was s hut down in April of 1982. The reverb and anode furnace were tom down for their brick., and the r e maining uni ts were rebricked with new brick pending a future start-up of the smelter . • Approx im ately three years ago , Asarco began cleaning out all copp er-b eari ng materi als, and began seeking markets for the re-bricked converters and other equipment. • The old converter aisle bas been c l eaned of a lmost all o f tlte accumulated reverts (photo 94). Brick removal dusts, clay. and some remaining revert-like material s were noted. EPA 

### XRF screeni ng r es ults indicated that some copper-bearing materials remained (Att. #8). • Four 55

- gallon drum s identified only with "Aqu a P hos'' s pray -painted on the lid were noted i n the rear ofthe converter aisle (photo 95) . Asarco represe ntatives stated the containers were not present during a walk-through inspectio n three weeks earli er, and could no t positively identify the co nte nts. Asar co stated they believed the contents may be Nalco fl oc. culants sui table for use i n water treatment (Alt . #31 ) . • In the Spare Parts room, two unmarked 35-gallon fibe r containers bolding an unidentified purple material were noted (photo 96). Using an o ld Kennecott container tracking system, Asarco identified the co nte nts as a Mob erg- brand algicide used in water treatment (Att . #32). • Asarco sub sequently identified the four 55-gallo n drum s ac; containing polyphosphate, and confirmed the two 35-gallon containers held an algicide . Doth chemicals are cooling tower water treatment chemi cals, and would 

### be eva luated for usab ility (Att. 

### #33) . Material identified as " fume" w as noted piled under the balloon flue dus t bins (photos 97 -98). Asarco promptly containeri zed (photos 99-100) and assayed the material, determined it conta ined approximate l y 12 . 6% copp er, and re mov ed it to the bedding p lant. · Kennecott S melter Regulatory I ssues: I ssue # 1: Used .oil spiiJ s were noted in the \oodiog area outside t he Ke nn ecott smelter, and a fi ve·gallon bucket ofu sed o il in the Tool roo m was not marked "Us ed Oi l" (photo 

### 10 I ). Asa rco promptly corrected the problem . See photo 

### I02 and Attachment #33 . Wa s te Accumulation Areas : Less Than 90-Day Hazardous Waste Accumu lation Area: 

### The fire extinguisher inspection tag 36 

## \CFR 

### § 261.1(c)(l-3). Because the soil is not one ofthe materials listed in 40 CFR 

### § 261.2(c), it is a s olid waste when recycled. Because the soil is nota spent material , sludge, or byproduct as defined 

## u. 40 CFR 

### § 261.1(c)( l -3), it cannot qualify for any of the reduced requirements for the reclamation of s olid wastes in CFR 

### § 261.2(c)(3). Because the soil is a solid waste that exhibits the toxicity characteristics for l ead and cadmjum, it.is a lso a hazardous waste prior to recycling or reclamation . Hazardous wastes that will be recycled are defined as " recyclable materials" in 40 CFR 

### § 261.6(a)(l). Gener.uors of recyclable material s must comply with the requirements fo r generators ofhazardous wastes (40 CFR 

### § 261.6(b)). Owners or operators of facil it ies that store recyclable materials before they are recycled are regulated 

### as treatment and storage facilities (except that the recycling process itself is exempt from regulation) (40 CFR 

### § 261.6(c)( l)) . RCRA hazardous waste storage requirements apply once hazardous wastes are generated. 22 The pertinent question now becomes : When is the hazardou s waste/recyclable material (soil) generated? EPA has consistently maintained that contaminated soi ls (that are not the result of illegal disposal) such as this copper-bearing soi l are generated when t hey are excavated and removed from the area of contamination13• 

### EPA recently reiterated thi s point in the LDR Phase 

### IV Final Rule, noting that: "... 

### if contaminated soil is not removed from th e land (i.e. ge11erated), LDR.s cann ot apply .. .in other words, LDR.s do not apply to contaminated soil in situ or force exca\,ation of contaminaled soil." (63 FR 28617) We were also concerned that road work adjacent to the dirt wall or routine maintenance ofthe wall cou ld mix the characteristica lly-hazardous copper-bearing soil with non -hazardous soil, rendering the combined soil both non -characteristic and unsuitable for reclamation. The LDR Phase 

### IV Final Rule, however, indicate this activity is not prohibited : "The Agency notes tlzat the normal mixing of contaminated soil from various portions of a site that typically occurs during the course of remedial activities or in the course ofnonna/ earthmoving and grad in

g activities is not considered intentional mixing of soil with non -media orprohibited soil with non prohibited soil and, therefor e, is not a type of impennissib/e dilution. " (63 FR 28621) Thus, the characteristically-hazardous copper-bearing soi l is a RCRA

- regu lated hazardous waste (and subject to the hazardous waste generation and storage requirements) when excavated and removed Deliberate mixing ofthe characteristic soil wi ch non-characteristic soi l to render the combined soils non -hazardous is prohibited dilucion . The mixing that typically occurs during normal road work or wall maintenance activities, however, is not prohibited.

n Storage is defined in 40 CFR 

### § 260.10 as the ",. .holding of hazardous waste for a temporaryperiod, at the end of which the hazardous waste is treated, disposed of, or stored elsewhere."

' 3 See th e Nationa l Oil and Haiardous Substances Contingency Plan (NCP) and subsequent amendments, EPA guidance letters , etc. 35Issue # I :

Details : Contaminated soi ls at the Hayden copper smelt er (..Hay den ") dis play the tox . icity characteristics for lead and cadmium (0006 and D008) and contain s ignificant quantities of copper (Atts . #8 and 1 5). If excavated or s ubsequently managed, would**~sarco** h ave to manage the soil as a hazardou s was te?

No recent spills or releases ofhazardou s waste were noted in thi s area . The s melter has been o peratin g for almost a century . Contam in a tes fro m the furnace stack, w ater run -off or du st from the road s upported by the dirt wall , windblown copper concentrate, etc. may have accumulated in the soil over time . If subsequently mffilaged, the soil would probabl y be introduced into the bedding plant as a concentrate or revert to recover its copper value . Analysis and Interpretation : Becau se the actual source of the lead , cadmium, and**~opper** in the soil could no t be detennined , we are not attempting to interpret whether the soil is characteristically hazardous because of hazardou s waste ''contained in" the soil , or if the toxic con s tituent s came from raw mate ria ls that have been absorbed or deposited in o r on tbe soil. Following EPA 's established policy 1 , we are thu s assuming the co ntamin ated soil does not conta in untreated hazardou s wastes placed after the effective date s of the applicable land disposal prohibition s . We are also not attempting to determine whether the s oil would meet the RCRA statutory e lements noted in 40 CFR 

### § 261.1 (b)(2), but restricting our**analy~is** to how the recycling o f the so il may be regul ated in 40 CFR Parts 261 through 268. The introduction of materials into the bedding plant that co ntain chara cteri sticallyhazardous quantitie s of toxi c meta ls along with s ubstantial amounts of copper was discussed in detail in the reverts iss ue . Tb e copper content o f th e soil ( 15-2 1% copper) a pproac he s that of-the concentrate (approximately 32%). A s previous ly noted, so me s melter operators consi der reverts co ntaining as little as 3% copper suitable for use in the bedding plant. Using the same ration ale already applied to the 

### fine reverts in the reverts issue , it would appear that the introduction of the soil into the bedding plant would not constitute treatment of the toxic metal s in th e s oil, but would be legitimate recovery of the copper. Thus, under the conditions di scussed 

# m the precious meta ls brick issue, the high-copper soil could be considered legitim ately re claim ed 

### b y the s melting proc ess upon introduction into the bedding pl ant. Unlike the reverts, however, the soil is not primarily . netallic in co mpos ition, is not directly generated by the s melting pr ocess, docs not have an established market value, and bas been left in place for a n exte nded period of time . Thus the soil is not "used or reused " as defined in 40 CFR 

### § 26 l.l (c) (5) , because it would be recl.airned in the s melte r and 

### it is not a co mme rcial chemical pr oduct. The soil is also not a spent materi!ll , s ludge, or byproduct as defined 

### in 40

:u "As discu ssed 

### in the April 2 9 , 1996 proposa l , the Agency continu es to believe that, if infonnation i s not available or inconclu s ive , it is generally**rea s~** **mable** to assume 

### that co ntaminated soils do not contain untreated h azardou s w astes placed after the effective date s of applicable land disposal prohibitions." (63 FR 286 19) 34Arizona's Aquifer Protection Program . • Sediments are cleaned from the sump quarterly. • EPA 

### analysis indicates the CP-1 

### sediments exceed the 

### Toxicity Characteristics for cadmium at 5.2 mgll and lead at 5.0 mg/L. Total mercury was 160 mglkg, TCLP at .02 mg!L (Att . #8). • CP-1 sediments are typically collected with a bucket loader and hauled to the bedding plant, where they are air dried**~d** then blended with the filter cake. • Asarco assay results and sediment handling records indicate the CP-1 sediments can vary from 12 

### to 54% copper and .92 to 35% lead (An . #29). • An Asarco contractor , Ace Pipe Cleaning, uses vacuum trucks to collect metal bearing dusts and sludges. Wash waters an<J liquids are sent to CP-l. Asarco bas determined the used plastic flex hoses exceed the Tox.kity Characteristics for cadmium at 2.2 mg/L and lead at 10.4 mg/L (Att . #30).



# -

- ...:. CP-1 Sump and Impoundment Regulatory Issues: See discussion under Revert Screening Area and Reverts HandJing. 

### ADDITIONAL AREAS INSPECTED: 

### Berm Dirt: Additional Process lnfonnation: (Supplements information 

### in Attachment #10) • Analysis and assay results reviewed during the investigation included TCLP analysi s for

..berm dirt .. (Att . #J 5). • Upon questioning, Asarco representatives stated the berm dirt contained approximately 15% copper, and identified the sample as soil from several locations along a dirt wall ("berm") down-gradient from the copper smelting furnace and up-gradient from a copper concentrate storage pi le . • The Asarco analysis indicates the berm dirt displays the Toxic ity Characteristics for cadmium at 4 . 6 ppm, and lead at 33 ppm (Att. # 1 5). • EPA a l so sampled soils from the earthen benn . 

### XRF data indicated the berm dirt contained 16-21 % copper, and EPA analysis results indicated the benn dirt displays the Toxicity Charac teri stics for cadmium at 1.1 and 4 . 2 mg!L, and lead at 

### 17 and 

### It mg!L (Alt. #8). 

### Benn Dirt Regulatory Issues : 33Asarco's "Procedure for Pre-Acceptance Review and Verification Upon Receipt of Secondary Materials at Asarco's Operating Smelting Facilities.. includes procedures for the acceptance ofprecious metals-bearing hazardous wastes, including compliance with the requirements of 40 CFR 

### § 266.112 (page 1 3, 

### Att #5). 20 Thus, although the selenium contributed by the precious metals bricks could be considered a "toxic along for the ride", Asarco is required to detcnnine that tbc selenium in the bricks does not "significantly affect'' the furnace residues (i.e. doeS not sib'Ilificantly increase the concentration oftoxic constituents of concern 

### in the Bcvill-cxempt smelting s lag). 

### As noted , with the transmittal ofthis report Asarco is being given the opportunity to demonstrate their compliance with 40 CFR 

### § 261.4(a)( 17). 

### IfAsarco does not avail themselves of this opportunity, the transmittal requests Asarco submit a copy oftheir one-time written notice s ubmitted pursuant to 40 CFR 

### § 266 . 100(g) and their documentation, pursuant to 40 CFR 

### § 266.112(b), demonstrating that the spent refractory brick from Asarco 's precious metals refinery in AmariiJo, Texas does not significantly affect 

### the Hayden residue . Pending receipt of thi s documentation, Asarco appears to be processing the precious metals brick to recover economicaUy-significant amounts ofprecious metals, not as a s ham means of disposing of the selenium present in the brick. The recycling of the precious meta ls brick into the copper concentrate, if Asarco can demonstrate their current practices do not significan tl y affect the residue, appears to be a legitimate means of recoverin g the silver and gold values in the brick . CP-1 Sump and Impoundment: Incoming Material: Run-off water; wash water; process drains. Outgoing Material: Water to processes; sediments to bedding plant pad. Additional Process lnfonnation : (Supplements infonnation in Attachment #I 0) • Asarco refers to "CP-1" as both the 100,000 gallon concrete sump and the lined basin/ impoundment that contains any sump overflow (photos**88~93).** • Prior to the lining being installed , the impoundment was the "Containment Pond". The concrete walled and floored sump was constructed, the impoundment lined , and the impoundment designated as overflow for the s ump (not routine storage) to comply with

20 The 40 CFR 

### § 266 Appendix VU limits are referenced under the legitimate recycling criteria 

### in this procedure (page II , All #5). 32At 6-14% silver, the value ofthe precious metals the bricks co ntribute to the s limes should more than off-set the costs oftransporting and crushing the bricks. Thus, introducing Amarillo's precious metals brick into Hayden's furnace feed is an economical way for Asarco to retrieve the value ofthe precious metals in the brick. The valueofthe material, combined with the fact that 

### it is shipped to the Hayden smelter on a hazardous waste manifest, should serve to ensure th at the precious metal s brick is properly managed and prevent the brick from becoming a part ofthe RCRA disposal problem . Thus, the precious metals brick contains economicaJly significant quantities of silver, is handled as a material that has value, is transported to the copper smelter on a Hazardous Waste Manifest (AU. #28), and is neither stored nor speculatively accumulated prior to reclamation . 19 Asarco thus appears to be in compliance with the requirements of40 CFR § 266 .70. As discussed in the Revert Screening Area and Revert Handling section, a primary copper smelting furnace (which i s an industrial furnace) is a Boiler or Indu strial Furnace (BIF) if it processes hazardous waste (40 CFR 

### § 266.1 00(a)). 40 CFR 

### § 266 . 1 OO(g) states that owners and operators ofsme lting furnaces that process hazardous wastes for recovery of economically

s ignificant amount s of precious metal s ''... 

### are conditionally exempt from regulation under thi s subpart, except for§ 

### 266.1 12... " if the s melter submits a one-time notification that the owner or operator c1aims the exemption, samples the waste as necessary to document the economica11y s ignificant amounts ofmetals, and maintain records of the analy sis results . 40 CFR 

### § 266.112 requirements include demonstrating that the haza rdous waste does not significant ly affect the residue by conforming with selected sampling and analysis criteria. 40 CFR 

### § 266 . 11 2 also s tates that the residue standards must be met for the furnace residues (i.e the copper sme lting s lag) to remain Bevill

- exempt under 40 CFR 

### § 261.4(b)(7) . The precious metals brick amounts to a very small percentage of the s melter feedstock, and Asarco is unquestionably co mply i ng with the 40 CFR § 266.112(a)(2) requirement that at Jeast 50% ofthe feed be normal, nonhaza rdou s raw materials. 

### It would appear unlikely that such relatively sma ll amounts of prec iou s metals brick would s ignificantly affect the smelter slag. However, Asarco's precious meta ls used refractory brick displays the Toxicity Characteristic for seleni um (Att. #27). Selenium is not found in sign ificant amounts in the normal smelting furnace feedstock, and thus any detectable amount of selenium in the resulting smelting furnace s lag cou ld "significantly affect" the slag (and its Bevill-exempt status). 40 

### CFR § 266.112(b)(I) states: 

### "The waste-derived residue must not cont ain appendix VIII, 

### part 261 constituents (toxic constituents) that could reasonably be attributable 

## io .-:,e**ha ~ardous**  

### waste .. . " Selenium is an appendix VIII, part 261 toxi c con stituent

19 Precious metals brick that is stored prior to crus hing , or is left on the ground after the crushing procedur e, would sub ject the smelter to the speculative accumulation record keeping requirements in 40 CFR 

### § 266.70(c). The purpose ofthe bedding plant is to blend various materials together to ensure a uniform feed for the furnaces . Thus the blending is an integral part of the smelting process, and the reclamation ofthe brick would commence when the crushed precious metals brick is mixed into the copper concentrate at the bedding plant. 31reclaimed (except asprovided under 40 CFR § 261.4(a){l7)) . " 17 With the transmittal of this report, Asarco is being given the opportunity to provide a copy oftheir notice submitted pursuant to 40 CFR 

### § 261.4(a)( 17)(v), and to demonstrate tb:tt De spent refractory brick is handled at all times in compliance with 40 CFR 

### § 261.4(a)(l7) at both their Amarillo and Hayden facilities. lf Asarco does not avail themselves of this opportunity , the solid wa s te exemption for the reclamation for spent materials (the used precious metal brick) a : 40 CFR 

### § 261.2(c)(3) would not apply, and the spent bricks from the precious metals smelter would be s olid wastes prior to recycling . Because the spent bricks also contain characteris tically-hazardous levels oftoxic metals , the solid waste brick s would also be hazardous waste s. The question now becomes: Is the Hayden copper smelter legitimately recycling the characteri s tically

- hazardous s pent precious metals brick? Hazardous wastes that will 

### be recycled are defined as ..recyclable materials" 

### in 40 CFR 

### § 261.6(a)(l). 40 CFR 

### § 261.6(a)(2)(iii) provides that recyclable materials from which precious metals are reclaimed arc s ubject to the Recyclable Materials Utilized For Precious Metal Recovery regul ations in 40 CFR Subpart F (40 CFR 

### § 266 .70). 40 CFR 

### § 266.70(a) states that "The regulations in this s ubpart appl y to r ecyclable materials that a re reclaimed to recover economically-s ignificant am o unt s of gold , si

lve r . . . " 18 Whether the process is economical is also one criterion in determining the legitjmacy of recycling. That is , whether the costs oftransporting the spent brick from Texas to Hayden , crus hing and s melting the s pent bric k at Hayden , and then s meltin g the electro

- refming slimes back at the Amarillo precious metals smelter would consistently exceed or be less than the value ofthe preciou s metals in the spent brick . As previously discussed, slime s containing precious metals are product s normally produced by the copper smelting industry during the electro

- refining of copper anodes, and Hayden 's anode s (with or without the enhanced silvervalue from the precious metals brick) are routinely e lectro-refined at Amarillo . Increa s ing the s ilver value of the anode s by introducing the precious metals brick into the Hayden furnace feed increases the market value of Amarillo ' s slimes without changing the routine cost oftransporting the anodes to Amarillo , electro-refining the anodes , and s melting the preciou s metal s slime s.

17 A s previously noted in the reverts issue, 40 CFR 

### § 261.4(a )(J7) requires certain handling and storage practices for mincrnl process ing s econdary material s. The .. Batt e ry " de c ision (Association of Battery Recyclers, Inc . et al v. United S tates Environmental Protection Agency, (D.C. Cir. No. 98-1368), decided April 21 , 2000) set aside the reference to 40 CFR 

### § 261.4(aX1 7 ) for characteri s tic-only byproducts and sludges (such as the fine reverts and acid plant blowdown) that are not solid wastes when reclaimed, but left intact the potential exclu s ion for spent materi al s that 

## m solid wastes when reclaimed. 19 And " .. . platinum, pa/adium, iridium, os mium, rhodium, ruthenium. or any c ombination qf th es e. " Although small amounts of these platinum group metal s are smelted from the s limes produced from Arizona copper ore, they were not noted in the MSDS for th e prec ious metal s brick and thus their value was not considered in thi s analysis . 

### 30arsenic, chromium, and selenium (0004 , 0007 , and DO 1 0). 15 The spent refractory bri ck ma kes up an extremely small fraction of the copper s melter feedstock. Incoming s pent r efractory brick is immediately crushed and mixe d with the copper concentrate (to prevent pilferage , according to a s melter representative), and then goes dire ctly into the bedding plant, where it is mixc:J with other feedstock and furnace ingredients (sand fluxes, lime, etc . ) From the front gate of the Hay den smelter to the furnace takes approximately nine to ten day s. 16 Hayden only accepts the s pent brick i f the precious metal value i s high enough (Att . #5). The brick is sh ipp ed to Hayden on a hazardous waste manif es t (Att. #28) . Analysis 

### and lnterpretation: The s pent refractory brick from Hayden' s copper s me lting furnace and convertors absor b copper during the s melting process. These spent brick s are then fine ly ground and introduced into the Hayden s me lter feed to recove r the ir copper value . Thes e bricks directly contribute copper to the c opper anodes at Hayden , and are best considered "by-products" as defined in 40 CFR 

### § 26l .l (cX3) and.fine r everts, as previously di scussed in the Revert Screening Area and Revert Handling iss ue . Hayden 's res ulting product, anode copper, is not on l y "commodity-like" (see 5 0 FR 655, 1/4/85 ) but is a c ommodity common ly listed on the metal s exchange markets. Ba sed on our understanding of the copper s melting process, the majority ofthe s ilve r and go ld in the incoming spent preci ou s metals brick would 

### be concentrated into the copper anodes al ong w i th the copper, thus increasing the value of the anode copper. Unlike 

## th e copper in the Hay den spent refractory brick , howe ver , the s ilver and go ld in the spent precious metal s brick are not fully recovered at Hayden. As previously noted , the Hayden anodes are sent to Amarillo, which electro-refines the anodes 

### and generates the precious-metal bearing s limes. AmariJio then smelts the sl imes to recover the s ilver and gold. Thus, the Hayden copper s melter concentrates the s ilver from the prec ious metals brick into the co pper anOdes, but the enhanced silve r value s arc a c tually recovered 

### in Amarillo. Hayden on l y partially reclaim s the s ilver by making it amenable for full reclamation by e lectr o-refin i n g and s melting at Amarill o . Thu s, unlik e the "byproduct" finely-ground copp er refractory brick Hayden produce s and re c laims onsite, the spent preciou s meta ls brick produced at Amarillo and transported to l:Iayden for partial reclamation are be s t c lassified as a "spent material" a s defined in 261.l(c)(l). 40 CFR 

### § 26 1.2( c )(3) and T able 1 of s ubpart 26 1 states that spent materials, " .. .

ar e solid wastes when

15 Asarco 's Ray Complex licen sed laboratory routinely analyzes for s el enium (see the various attached assay/analyt ical results , and the Waste Analysis di scussion below) . We noted , howe ver, that the li st of tar get TCLP metal s 

### in Appendix 7 ofAsarco 's corporate-wide "Procedure for Pre-Acceptance Review and Verification Upon Re ce ipt of Secondary Material s at A sa rco' s Operating Sm e lting Facilities" does not include selenium (Att. #5 ) . 16 Asarco smelts 2,500 ton s/day, so eac h 6,000 ton bin at the bedding plant takes a aro und 2 . 1 to 2 .3 days to smelt. With four · bins (one being s melte d, o ne waiting, two being bui lt), the bricks would pass into the sme lter in about 9 days. 29• The furnace brick is composed of60

- 75% chrome ore and magnesium chromium oJCide (An . #25). • The furnace brick passes the TCLP for chrome (An. #10, and Asarco assays and 311l!ly3 is reviewed during the inspection) . • A sarco analysis of the converter and anode refractory brick do not display any of the Toxicity Characteristics (An. #26) . Brick Regulatory Issues : Issue #1 : Issue #2:

Details: Sec discussion under Revert Screening Area and Reverts Handling. Asarco's Ray Complex Hayden Smelter ("Hayden") is a primary copper processing facility that accepts spent refractory brick from Asarco 's precious metals refinery in Ama rillo , Texas ("Amarillo"). Hayden immediately crushes the incoming brick (in the "Smithco" crusher) and mixes it with other incoming raw materials destined for the copper furnace. Is the use of this brick legitimate?

The same grinding, flotation, and smelting processes that concentrate the copper present in the ore also concentrate the gold and silver present in the ore. The copper ore contains a bout 0.3% copper . The smelting process produces copper anodes containing 99.9% to 99 . 99% copper. Most copper smelters then electro-refine the anodes. In electro-refining, the copper in the anodes is electroplated onto copper cathodes (99 . 999<'/o pure copper) . The 0 . 1% to 0 .01% of non-copper metals in the copper anodes collect in the electrolyte and are removed as "s limes". The slimes had a market value of about $8-$15 a gallon during our investigation in August of 2 000 (price varies with assay results and gold and silver prices), and are the way gold and s ilver arc nonnally produced and sold by copper smeJters . The Hayden primary copper smelter does not operate an electro-refining unit. Asarco sends the Hayden copper anodes to tbeir Amarillo facility . Amarillo docs the electro

- refining, and also has a precious metals refming unit that refines the clectro·refining slimes along with other compounds containing gold and silver (dore'). This sister facility's precious metals unit generates spent refrac\ory brick from inside the bottom blown cupels. According to facility representatives, the Amarillo precious metals refinery cannot recover precious metals fTom the spent brick, but the Eayden copper smelter can. The copper smelting process co ncentrates the precious metals into the anodes, where they can later 

### be recovered 

### by electro-refining and precious metal s smelting. The material safety data sheet for the spent precious metals refractory brick (Att . #27) indicates that it contains approx.imately 6-14% silver, l-4% selenium, 1-2% copper, " le ss than l%"1cad and arsenic, some ..mixed oxides" ofother toxic metals, and is characteristic for



### 28cadmium and lead. A copper smelti ng furnace (which is an industrial furnace) is a Boiler or Industrial Furnace (BIF) if it processe s hazardous waste (40 CFR 

### § 266 . IOO(a)). "Taxies along for lite ride ., are evaluated at BlFs by determining if

### the taxies ..significantly affect" the furnace residues (i .e . the BeviJJ-exempt smelting s lag) (see 40 CFR 

### § 266 . 112{a)(2) and (b)(l)) . Although the smelter is not processing a hazardous waste if the reclamation is legitimate, the BIF regulations arc s tilt use ful in determining the affect of the toxic metals on the Be vill -ex empt slag . 14 The toxic metals · in Asarco's.fine re verts appear to have originated in the nonn al copp er concentrate and smelter feed . Since cadmium is already pre s ent in the sme lter fee d, "e ha\· c determined that the r e- introduction and recycling of the relatively small quantities of characteris tically hazardous

### .fine reverts into the concentrate and sme lter feed is unlikely to "significantly affect" the s lag. Thus, the 

### fin e reverts are being legitimat e ly reclaimed in the smelter. Brick: Bricks generated at the Hayden Smelter are handled in a portion ofthe reven screening area.

· Incoming Material: Refractory brick from the flash furnace, fu01ace launders, conveners; and anode furnace; used**a~id** plant brick ; used refractory brick from Asarco's Amarillo, Texas precious metals 

### refmery . Outgoing Material : Revert copper to the converters (via Bunker# 1 ); crushed brick to the concentrator: launder bricks to the converter aisle (photo 86) . Additional Proce ss Information: (Supplements information in Attachment # I 0) • Bricks are accumulated 

### in 50-ton piles, then sorted by hand for visible copper . • For the purposes ofthis investigation. bricks with visible "ribbon s" of copper (absorption) used 

### in the converters were considered analogous to 

### large reverts (photo 87). • MSDSs for a variety of Asarco refractory bricks form Attachment #25.

11 The reverts appear to meet the BIF limits in 40 CFR 

### § 266 . J 00( d)(2}, contain le ss than 590 ppm cyanide, and comprise le ss than 50% ofthe feedstock . 27of the material are recovered as separate endproducts (as wllen metals are recovered/rom metal-containing secondary materials). . . " (40 CFR § 261.l(c)(5)(i) , emphasis added) . 40 CFR § 261.l(c)(4) defines "reclaimed" as : "A material is "reclaimed" 

## if it isprocessed to recover a usableproduct, or 

### if ills regenerated . Examples are recovery of lead values from spent batteries ... ". Thus, because A s arco recovers copper from the re. verts as a s eparate end produc t, and also because this recovery constitutes reclamation, the fine reverts do not qualify for the "used or reused" solid waste exclusion in 40 CFR 

### § 261 . 2(c)(l )(i) . Tbefine reverts could also be considered ''used or reused" if they are u s ed as an effective subs titute for a commercial product, i . e . copper concentrate (40 CFR 

### § 261.l(c)(5)(ii) and§ 261 . 2(e)( 1)(ii)). However, EPA has previously indicated in guidance documents and preamble language (50 FR 619) that the same reclamation issues applicable to ingredients can apply to product substitutes. Therefore, the

### .fine reverts do not qualify for the "used or reused" exclusion (40 CFR 

### § 261 . l(c)(5)(ii) and§ 261 . 2(e){l )(ii)) because the smelting process itselfconstitutes reclamation (see 40 CFR 

### § 261.1(c )(4)). The fine reverts, however, are not listed hazardous wastes. Because the fine reverts are not listed hazardous wastes and are not speculatively accumulated, whether they are considered "by

- products" as.de.ftf!.ed in 40 CFR 

### § 26l.l(c )(3), "sludge( s ]" as defined in 40 CFR § 260.10 , or mineral proces s ing "secondary materials" (see 40 CFR 

### § 261 .4(a)(17)), they are not solid wastes when legitimately reclaimed by the smelting process (40 CFR 

### § 26l.2(c)(3)). The question now becomes: Are the fine reverts legitimately reclaimed by the smelting process? The smelting process clearly recovers the copper value in the reverts . One criterion in determining the legitimacy ofreclamation i s whether there are "toxics along for the ride" . 12 EPA has stated : ' 'Situations most likely to be deemed sham recycling would, thus, be those involving low amounts of recoverable maten· alplus the presence of non-contributing hazardous constituents in the waste (particularly hazardous constituents not otherwise present 

### in the nonnalfeedstock of the process)." {63 FR 28587) As noted , the fine reverts contain significant amounts ofcopper. A portion (if not the majority) of the lead in the.fin e reverts will be removed in the drum filter cake and sold to A s arco' s lead smelter. Cadmium, which some of the fine reverts contain in concentrations that exceed the To x icity Characteristics, is a non -contributing hazardous constituent. However, cadmium appears to be present in tbe normal feedstock ofthe processes , and the same smelting processes that concentrate copper into the reverts also concentrate the heavy metals . 1 3 Although the cad.. 1ium is .. along for the ride", the.fine reverts are being introduced into the smelting proces s primarily to reclaim their 

### high copper content, not as a sham means of disposing of

u Sec 53 FR 522 (1/8/88) , 

### 52 FR 1701 .3 (5/6/87) , and 50 FR 638 (1/4/85) for examples ofrecycling legitimacy criteria . 11 Unlike some ofthe secondary materials reportedly utilized in the smelting of other metal s (cathode ray tubes being crushed at lead smelters, etc . ), the fine reverts are generated during the copper smelting process and the toxic metals found in the fine reverts appear to have primarily originated from the ore. 26re-introduction ofreverts as a means of recovering copper that would otherwise escape from the smelter processes. The same grinding, flotation, and smelting processes that concentrate the copper p:'!Sl:nt in the ore also concentrate the arsenic , lead, mercury, and other Toxicity Characteristic metals present in th e ore. These toxic metals are concentrated into the reverts along with the copper . Reverts are usually assayed for copper content but not for toxic metals, because the smelter does not consider reverts a waste . The large rev erts, sometimes called .. cobble", are usually generated in or adjacent to the co nverter ais le . They typically contain over 50% copper. After any needed crushing and sizing, the majority ofthe large reverts are either fed directly into the furnace or are used in the converters as "cold

-dope". The ongoing reactions in the converters are exothermic, and the co ld metal piece s are used as "dope" to co ntrol th e temperature inside the converters. These large reverts are required for the ongoing operation ofthe converters, and are stored, bought, or sold by smelters depending on need. The large reverts are often stored on the ground' 1 and were not being speculatively accumulated at the time of the inspections. In contrast, the fine reverts are normally reused by blending them into the smelter f eedstock. The fine reverts have a market value and are routinely sold by Asarco, are usually stored on the ground, and were not being speculatively accumulated during our inspectjon. The fine revert s sampled during the investigation contai ned approximately 40% copper and exceeded the Toxicity Characteristics for lead and cadmium . Asarco considersfine reverts conta ining as little as 3% copper suitable for blending with the concentrate. Analysis and Interpretation: We have detennined that the large reverts are typically used by returning them directly into the ongoing smelting process . Essentially, they 

### are pieces of copper being used as copper . Molten metal gpilled onto smelter floors is not a solid waste if it is picked up as practical and placed back into the smelting process (63 FR 28583}. We have determined that the large reverts or cobble. if not speculatively accumulated, are not solid wastes when used in this manner. The status ofthefine reverts appears to require a more detailed analysis. Materials arc not so lid wastes when they are legirimarely recycled by being ..used or reused" as an ingredient in an industrial process to make a product, provided the materials are not being "reclaimed" (40 CFR 

### § 261.2(e)(l)(i)). Material s are ·· used or reused" if they are "...employed as an ingredient.. .in an industrialprocess to make a product ... " 

### except where " ...distinct components

11 40 CFR 

### § 26L4(a}(l7} requires certain handling and sto rage practices for mineral processing secondary materials. 40 CFR 

### § 26L2(c)(3), as codified, referenced thes e requirements for mineral processing secondary material s that are reclaimed . The "Battery" decision (Ass ociation ofBattery Recyclers, Inc . et al v. United States Environmental Protection Agency, {D.C . Cir. No. 98

- 1368), decided April 21, 2000) set as ide the reference to 40 CFR 

### § 26 

### f .4{a)( 17) for characteristic-only byproducts and sludges (such as the fine reverts and acid plant blowdown) and that are not solid wastes when reclaimed . 25• Asarco hasn't received post-constmer scrap copper in bulk in several years . • Copper

-bearing reverts are measured in the monthly metal balance. An additional 400 tons of"copper tools ", s uch as the anode molds and the bumping block, are also inve ntoried . Revert Screening Area and Revert Handlin g RegyJatorv Issues : Issue# 1:

Details : Analytical results show that " reverts" from copper smelting operdtions can be characteristically hazardous for lead and cadmium, and can contain 50% copper. Ifthe revert material bas . mu cb higher concentrations of copper and toxic metals than the ore, is re-introduction oftbe revert material into the smelter process legitimate?

The copper ore typically contains approximately 0.3% to 0.6% copper. Analytical results show that the copper concentrate made from the ore is ap prox.imately 27% copper (Att . # 14), and exceeds the Toxicity Characteristics for lead (Att. #8). After smelting , the copper anodes contain approximately 99.4% copper. During the s melting process, copper smelter operators generate a variety of copper-bearing materials they call "reverts" . For the purpose s 

### of thi s discussion, we are dividing reverts into two broad categories: 

### "Large" revert s: Fairly large, dense and solid pieces of metal or primarily metallic material (including slag , matte , and blister copper) gene rated from the cooling of molten rrietal that bas escaped or been removed from the s melting or converting process . This category of reverts include metal that bas cooled on the inside of ladles (skulls), drips and sp ill s from the handling of molten metal, and high-copper content material tbat has been skimmed from the s urfac e of converters. 

### "Fine" revert s: Cooled copper from smaller splas hes and drips, along with copper bearing sands, mud, sweepings, drum and filter cake, CP-1 water s ump solids, etc. generated during or subsequent to the s melting process. These reverts are finer in particle size than the often large a nd solid pieces of metallic copper di scussed above . Unlike other Arizona primary copper smelters in their submittals to EPA, Asarco consistently used the term "reverts" to refer only to the same kind of materials we have defined as large reverts above (Att. # l 0) . Asarco properly refers to the s ump solid s, dusts, filter material, etc. that we have defmed as

### .fine reverts by their proper source name. For example , sediments from the concrete sump at CP-1 are referred to as "concrete sump sediments" (Att . #29). 

### lo the interest ofbrevity, we will consolidate the se materials under the term 

### ''fine revert s'' in tbis discussion. Because the initial concentration ofcopper in the ore is so low , materials that could b e co nsidered .. waste-like" in other industries (sol ids from the bottom of sumps, etc.) contain copper values several orders of magnitude hi g her than the ore. Asarco considers the 24Outgoing Material : Bedding plant and furnace feed; cold dope to the converters and anode furnace; mi ll and con centrator feed; reverts and blister copper sa l es . Additiona l Process Information : (Supp l ements information in Attachment# l 0) • The reverts sorting area held approximate ly 300 tons of copper ladle and slag skulls . The skulls and converter ais le r evens are d r opped onto a 4" "grizzly '' screen to sort them by size . Skulls p ieces larger than 

### 2" are sent to the converters . Smaller material is sent to the ..Smitbco " crusher and hence to the bedding plant or for r evert sale s . • Asarco analyses of various revert material are included as Attachment #24. The Asarco analy s es indicate : • The vent gas Cottrell dust displays the Toxicity Characteri stics for cadmium at 127 ppm, and lead at 8 .750 ppm ; • The converter cyclone dust displays the Toxicity Characteristics for cadmium at 39 . 7 ppm , and lead at 9 . 3 ppm ; • The converter hood dust displays the Toxicity Characteri stics for cadmium at 4.5 ppm, and lead at 12 . 9 ppm ; • Reverts in the converter aisle dust display the Toxicity Characteristic for lead at 13.9 ppm; • The converter hood dust displays the Toxicity Characteristics for cadmium at 4 . 5 ppm, and lead at 12 .9 ppm ; • The delumper reject dust displays the Toxicity Characteristics for cadmium at 16.1 ppm, and lead at 39 . 7 ppm; • The converter bood dust displays the Toxicity Characteristics for cadmium at 4 . 5 ppm , and lead at 12 . 9 ppm ; • The baghouse bags di splay the Toxicity Characteristics for cadmium at 47 ppm, and lead

· at 1 

## o

.ppm; and, • The filter rock displays the Toxicity Characteristic s for cadmium at 1.38 ppm, and lead at 63 . 1 ppm. TCLP results for mercury were less than 0 .002 ppm. • Asarco produces about 3 00 ton s per day of combined reverts , of which approximately 1

00 tons a day are used directly in the converters . • At the time of inspection, Asa.rco was**purc~asing** roughly 2,500 tons per month ofblister copper (post-converter, but not yet fired in the anode furnace) , and selling about 500 tons per month of r e vert fines . 23· arsenic at 39 mg/L, cadmium at 

### 5 mg/L, and lead at 8.9 mg/L. Total mercury is 79 mglkg, but passes the TCLP for mercury at less than .02 mgiL (Att . #8). Asarco analysis· indicates the drum filter cake displays the Toxicity Characteristics ior cadmium at 49 ppm, and lead at 61. 1 ppm. TCLP results for mercury were Je ss than 0.002 ppm (Att . 

### #2 1 ). • The drum filter cake, in addition to the approximately 40% lead , contains 2-4% copper . • Asarco generates about 700 tons/day (approxjmately 2,000 tons per month) ofplate filter

cake . • Asarco analysis indicates the plate filter cake displays the Toxicity Characteristics for cadmium at 56 ppm, and lead at 51.1 ppm . TCLP results for mercury were less 

### than 0 .002 ppm (Att .**#2~) .**  • Asarco noted the pla te filter cake contains zinc fume and fine zinc particulate , making the removal of water 9ifficult . The plate filter cake is solar dried on the filter plant 's conc rete p ad. • Asarco analys is indkates spent plastic grid contacts in the ftlter plant press displays the Toxicity Characteristic for lead at 26 ppm. Asarco also generates used rubber linings at the fllter plant that displays the Toxicity Characteristics for lead . The spent plastic grids and rubber linings arc sent ofT-site as hazardous wastes (Att. #23) . filter Plant Regulatory Issues: See the discussions in : Heap Leach; Gas Cleaning System and Sulfuric Acid Plant ; Revert Screening 

### Area and Reverts Handling . Revert Screening Area and Reverts Handling: Revert handling areas not already depicted and the Revert Screening Area are shown in photos 67-85 . lncoming Material; Material considered "reverts''can include: Metallic reverts including solidified matte, bli s ter cooper, and converter s lag from minor splashes and spills; used refractory bricks; ladle skulls; solids from the CP

- 1 impoundment; plate filter cake ; baghouse bags; delump er rejects; particulates from the flas h furnace wet gas scrubbing system and Acid Plant blowdown; anode slag (to the converters); used refractory brick; 9-bin pump tails; the condensed fumes , dusts. and filter rock discussed in the Bedding Plant Area, Delumper, and Dryer section; 

## and other miscellaneous copper-bearing materials . 

### 22above, the catalyst is used in the manufacturing of sulfuric acid. Therefore , the used catalyst is a manufacturing process waste . Because the used catalyst is a manufacturing process waste, it does not meet the 

### vanadium pentoxide 

### listing in 

### 40 CFR § 261 . 33. 10 The used catalyst is also not a li s ted process waste (the 

### K 171 and 

### K 172 listings apply only to the catalysts generated at petroleum refmeries) . Thus, the used catalyst is being l egitimatel y used or reused as an ingredient (silica) in the smelter feed, and is not a solid waste (40 CFR 

### § 261.2(e)(l)). Filter Plant: lncomine Material : Particulates from the flash furnace wet gas scrubbing system;·blowdown from the Acid Plant Gas Cleaning system . Outgoing Material: 

### -



## _ ., Plate ftlter cake to the bedding plant (30% copper); flash furnace scrubber blowdown returned to the scrubber syste m ; 

### drum filter cake (so li ds from 

### the Cone settler) to Asarco's East Helena lead smelter; CSO acid to the heap leach . Note: Asarco's submittal discussed the cone settler overflow (CSO) in the Filter Plant section (Att. #10). For clarity purposes, we have dis cussed the CSO in the Gas Cleaning System and the S ulfuric Acid P lant section and in the Heap leach section. · Additional Proces s Information : (Supplements information in Attachment 

### #10) • The filter plant and fil ter process is shown in photos 61-67. • Asarco generates about 100 tons/month of drum filter cake (photo 67) . • EPA analysis indicates the drum filter cake disp lays the Toxicity C haracteri s tics for impregnated beads . We believe this indicates the vanadium pentoxide-impregnated beads are considered unfit for use because the size of tbe silica beads falls below specifications, not because the vanadium pentoxide is consumed, contaminated, or no longer chemically e ffecti ve as a catalyst. 10 The comment in 40 CFR 

### § 261.33 sta tes &bat " ... The phrase 'commercial chemical product' ...does not refer to a material , such as a manufacturingprocess waste , that contains ally of the substances listed in paragraphs (e) or 

### (f) [including P 120). Where a manufactun'ng proces s waste 

### is deemed 10 be a hazardous waste because it contains a s ubstance listed in paragraph (e) or 

### (f), such waste will be listed in either§ 261.31 or§ 261 . 32 or 

### will be identified as a hazardou s waste by the characteristics setforth in Subpart 

### C of this part." 21saddles do not display any ofthe toxicity characteristics (A" . #18). Asarco bas also determined that tbc catalyst fines are as effective a fluxing agent as the crushed silica from mines that is nonna11y used in the smelter feed, and that the catalyst fines are directly used as an ingredient (silica) in the smelter feed; thus, the undersized silica beads were never a solid waste . 

### The imes contain approximately 7% vanadium pentoxide, about 

### the same percentage as the new impregnated beads. Vanadium pentoxide is a commercial chemical product listed in 40 CFR § 261.33 as acute hazardous waste number P 120 if and when discarded or intended to be discarded . Asarco reported the crushed, silica-containing quartz rock is routinely used in the smelter feed as 

### a ..flux " to " ... combine with iron and alumina from the concentrate or matte and remo-v-e il as slag . "(see definition of

### flux, page 4, At1 . # 

### l 0). Asarco uses the vanadium pentoxide impregnated silica 

### fines 

### as a substitute for silica sand mined from quartz. The mined si lica sand does not appear to be characteristic for toxic metals or contain detectable levels of vanadium pcntoxide. Rough calculations indicate that the vanadium pcntoxide in the s ilica is about 00.00025 % of the total feedstock used by the smelter each year. The boiling point of vanadiUm is much higher tlian the working temperature of the copper smelting furnace, which indicates the vanadium 

### in the spent cata lyst fines will not vaporize and enter the furnace exhaust stack. Instead, the vanadium pentoxide will likely chemically reduce in the furnace to a vanadium metal, and would be removed (along with iron and alumina) in the Bevill-cxempt slag . Petroleum refmeries also use vanadium catalysts to convert 

### S0 2 gas into 

### S0 3 gas. The spent vanadium catalysts used for hydrorefming and bydrotreating 

### in petroleum refining operations are K171 and 

### K 172 listed hazardous wastes. Concerns about the toxicity of vanadium pentoxide was one reason the wastes were listed7 The .. inert support media" for 

### K 171 and K 172 are exempted from the definition ofhazardous waste (40 CFR 

### § 261.3(c){2)(ii){E)) . Analysis**an~** Interpretations : Although the vanadium pentoxide is the sole active ingredient in the catalyst, 8 tt ts not

..spent" after use, 9 and therefore does not meet the P 120 hazardous waste listing. As detailed The " ... self-beating pyrophoric properties and potential reactivity... " of the sulfides in the refinery wastes were also a concern (60 

### FR 57783-85 and 63 

### FR 42168) . This is not a concern at copper smelters . where the pyropboric reaction of the sulfur in the ore is used to heat the furnace . ' The s ilica beads appear to act as a support media to increase the surface area exposing the catalyst impregnated in the beads to the 

### S0 1 gas streams, not 

### as an active ingredient in the conversion of 

## sol gas to 

## so) gas . ' 40 CFR 

### § 261.1(c)(l) : "A 'spent material' i s any material that has**~een** used and 'OS a result of co ntamination can n o longer serve thepurpose for which it was produced without pro cessing ... " According to facility submittal s, when remov ed from the converting tower, the fines contain**approxi~ately** the same percentage (7%) ofvanadium pentoxide as the new 

### 20• Chrome

- containing corrosion inh ibit<.rs are not used in the cooling tow e rs. T he make

- up water is demineralized water. • Asarco's MSDS, analysis, and assays for the acid plant materials indicate: The ceramic saddles (photo 60) contain 3 7.2 ppm mercury (0.8 ppb TCLP) {Att. #18) . The vanadium pentoxide fines contain 0.6 ppm mercury {<0.5 ppb TCLP) (Att. #18). The polypropylene pl as tic saddl es from the cooling tower often display the toxicity characteristic for le ad (Att. # 19) . Mist eliminator filters fail TCLP for chromium, which is attributed to the stainless steel piping in tbe acid plant (An. #20). • Asarco generates approximately 40 tons of quartz rock and s ilica beads every two years. • Asarco generates about I0 cubic yards per year of waste polypropylene plas tic saddles. The plastic saddl es are shipped off-site a s a hazardous waste {Alt. #19). • Asarco generates abo ut 40 cubic yards of mist eliminator filters once every 10 years. The mist eliminator filters are shipped off-site as a hazardous waste (Att . #20). • Asarco ha s a calcium sulfide surface impoundment wbich was used from 1973 through 1992 to dispose ofwastewater treabnent sludges from the ac id plant. 40 CFR 

### § 261.4(bX7)(ii)(H) states that calcium sulfate wastewater treatment plant s ludge from prjmary copper processing are not hazardous w aste s, and thus the calcium sulfate surface impoundment was n o t evaluated during this inve sti gat ion . Gas C leaning System and Sulfuric Acid Plant Re gulatorv I ssues: I ssue #I : I ssue #2: Details: See the discussion on the use of CSO weak acid in the Heap Leach sect ion . Asarco uses spent silica impregnated with vanadium pentoxide as a substitute for mined silica. Is this practice legitimat e?

Vanadium pentoxide (V 1 0s) is used as a catalyst in the acid plant' s c onverting tower to convert 

# so2 gas into 

# sol gas . The vanadium pentoxide is impregnated into silica beads s upported by a bed of quartz rock . After a period of time the phys ical size of the silica beads becomes small enough to inhibit the flow ofgas through the catalyst bed . The undersi zed bead s and pieces ofbead s ("fines'') are phy s ic ally**scree n~**  out ofthe catalyst bed . The coarse materials are reu sed in the converting to wer . The u sed catalyst fin es arc typically stored in large woven fiber containers called "supersacks", and were not being speculatively accumulated at the time ofinspection . Asarco 

### has determined that the spent catalyst fines , quartz rock bed, and the ceramic 19• According to Asarco representatives, tbe historic s lag contains abo ut 0 . 6% copper, and the economical cutoffpoint is about 1 .0% . S lag b as been successfully remiJied since the early 1990's. A sarco shut down tbe :.:- e lectric furnace for slag cl eaning in 1996 . S lag from prim ary copper processing is not a hazardous waste ( 40 CFR 

### § 26l.4(b)(7)(ii)(A)). S lag Handling Resmlatory Issues : None . 

### Gas Cleaning Sy stem and Sulfuric Acid Plant: Incoming M aterial: Flas h furnace and converter off-gases; blowdown water ; aci d plant brick; quartz and plastic support me dia; vanadium pentoxide cata l ysts. Outgoing Material : Sulfuric acid; CSO and ac id plant blowdown ; sil ic a beads (catalyst fines) to bedd ing plan t ; quartz. rock and ce rami c s addle s; u sed pla sti c sadd les; used acid p lant brick; dusts; filter cake. Addi tional Process Information : (Supplement s informati on in Attachment #10) • Photos 56-60 show different aspects ofthe ac id gas hand ling and particul ate coll ection systems . • The acid plant bas been in operation since 1983. • The plant produces about J ,700 metric ton s of sulfuric ac i d p er day. About half of tbe acid is sold and half used for leaching . Asarco stated that they will often buy ac id for l eac hing while selling their higher grade acid. • Du st exiting the Cottrell electrostati c precipitator conta in s about 

### 200/o copper. • CSO acid bas a pH of 1 .0 and fail s the toxicity characteri sti cs for arse ni c, cadm ium , lead, and sele nium (Att . #8) . The CSO acid also contains 4000 micrograms/L vanadium . Note: Sample AS13, described as "Tank #1" in the EPA analy s is in Attachment #8, is di stilled water that was u sed as a field blank. • The water shown 

### in Figure 

### 5 of Attachment #JO is fres h water . 18Anode Barrel Furnace, Remelt Vessel. and Casting Wheel Regulatory Issues: None. Baghouses: Incoming Material: Co nv erter fugitive gases and dusts from the secondary hood system; lime. Outgoing Material: Particulates to the pug mill, hence to the bedding plant; spent bags to the converters (about 7% copper); gases vented through the 1,000 foot stack. Additional Process Inf ormation : (Supplements inf ormation in Attachment # 1 0) • The baghouses contain approximately 11 ,000 polypropylene and No m ex bags . Baghouses Regulatory Jssues ; See the 

### Re,,ert Screening Area and Reverts Handling discussion . Slag Handling Areas: 

### The slag handling area and processes are shown in photos 48-55. Inc oming Material: Approximately 1200 tons/day of slag from the flash furnace; water. Outgoing Material: Frdctured slag less than l" in diameter to the rod mill feed; slag larger than 1" to the crusher; evaporated water. Additional Process lnfonnation : (Supplements infonnation in Attachment #I 

### O) • The s lag is poured about 1/4" to 

### 'h" thick onto a 30 degree s lope. • Areas of the Hayden Smelter, including the bricks and reverts handling area, are located on top of the "histori ca l slag area" . About 25 million ton s of s lag had been deposited since 1911. 

### l7