Document BRXKjOE7bk4989n2OyjobXVpJ

RCRA Inspection Report 1) Inspector and Author of Report Sarah Rowell Environmental Engineer Phone: 404-562-9418 Sarah.Rowell@epa.gov Laurie Benton Senior Enforcement and Compliance Specialist Phone: 404-562-8948 Laurie.Benton@epa.gov U.S. Environmental Protection Agency, Region 4 Enforcement and Compliance Assurance Division Chemical Safety and Land Enforcement Branch RCRA Enforcement Section 61 Forsyth Street, S.W. Atlanta, Georgia 30303 2) Facility Information Micross Advanced Interconnect Tech 3021 East Cornwallis Road Durham, NC 27709 EPA ID#: NCD018946590 NAICS #: 54171 - research and development in the physical, engineering, and life sciences 3) Responsible Officials Giao Nguyen Environmental, Health and Safety Manager giao.nguyen@micross.com 4) Inspection Participants Giao Nguyen, Micross Ben Sewell, Micross Jenne Hughes, NCDEQ Angela Murphy, NCDEQ Sarah Rowell, USEPA Laurie Benton, USEPA 5) Date of Inspection March 6, 2025, at 0900 6) Applicable Regulations1 Resource Conservation and Recovery Act (RCRA) Sections 3002 (42 U.S. Code - Annotated U.S.C.A. 6925 and 6927), and 40 Code of Federal Regulation (C.F.R.) Parts 260 - 270, 273, 278, & 279; Title 15A of the North Carolina Administrative Code (NCAC), Chapter 13. The North Carolina Solid Waste Management Law, N.C.G.S. 130A-17 to-28 and 130A-290to -310.22, and North Carolina Hazardous Waste Management Rules, 15A NCAC 13A .0101 to .0119. 1 As the State's authorized hazardous waste program operates in lieu of the federal RCRA program, the citations of those authorized provisions will be to the authorized State program. However, for ease of reference, the federal citations will follow in brackets. Pursuant to 15A NCAC 13A .0102(b) [40 C.F.R. 260.10], a large quantity generator of hazardous waste (LQG) is a generator who generates greater than or equal to 1,000 kilograms (2,200 pounds) of non-acute hazardous waste in a calendar month. Pursuant to 15A NCAC 13A .0107(a) [40 C.F.R. 273.9], a large quantity handler of universal waste (LQHUW) is a universal waste handler who accumulates 5,000 kilograms or more of universal waste (batteries, pesticides, mercury-containing equipment, lamps, or aerosol cans, calculated collectively) at any time. Pursuant to 15A NCAC 13A .0107(a) [40C.F.R.262.17], a large quantity generator may accumulate hazardous waste on-site for 90 days or less without a permit or without having interim status, as required by 15A NCAC 13A .0107(a) [Section 3005 of RCRA, 42 U.S.C. 6925], provided that the generator complies with the conditions listed in 15A NCAC 13A .0107(a) [40C.F.R.262.17] (hereinafter referred to as the "LQG Permit Exemption"). Pursuant to 15A NCAC 13A .0107(a) [40 C.F.R. 262.15(a)], a generator may accumulate as much as 55 gallons of non-acute hazardous waste in containers at or near any point of generation where wastes initially accumulate, which is under the control of the operator of the process generating the waste, without a permit or without having interim status, as required by Sections 130A-294(c) and (g) of the NCSWML, N.C.G.S. 130A-294(c) to (g) [Section 3005 of RCRA, 42 U.S.C. 6925], and without complying with 15A NCAC 13A .0107(a) [40 C.F.R. 262.16(b) or 262.17(a)], except as required in 15A NCAC 13A .0107(a) [40 C.F.R. 262.15(a)(7) and (8)], provided that the generator complies with the satellite accumulation area conditions listed in 15A NCAC 13A .0107(a) [40 C.F.R. 262.15] (hereinafter referred to as the "SAA Permit Exemption"). Pursuant to 15A NCAC 13A .0107(a) [40 C.F.R. 270.1(c)(2)(v)], owners and operators of hazardous waste management units must have permits during the active life (including the closure period) of the unit. However, owners and operators of elementary neutralization units or wastewater treatment units as defined in 15A NCAC 13A .0107(a) [40 C.F.R. 260.10] are not required to obtain a RCRA permit. Pursuant to 15A NCAC 13A .0102(b) [40 C.F.R. 260.10], an elementary neutralization unit means a device which is used for neutralizing wastes that are hazardous only because they exhibit the corrosivity characteristic, or they are listed in subpart D of part 261 of the chapter only for this reason; and which meets the definition of tank, tank system, container, transport vehicle, or vessel. Pursuant to 15A NCAC 13A .0111(b) [40 C.F.R. 266.70], persons who generate, transport or store recyclable materials that are reclaimed to recover economically significant amounts of gold, silver, platinum, palladium, iridium, osmium, rhodium, ruthenium, or any combination of these must comply with the conditions for Recyclable Materials Utilized for Precious Metal Recovery listed in 15A NCAC 13A .0111(b) [40 C.F.R. 266.70(a)-(d)], which are included in the Standards for the Management of Specific Hazardous Wastes and Specific Types of Hazardous Waste Management Facilities found in 15A NCAC 13A .0111 [40 C.F.R. Part 266]. EPA-RCRA CEI Report March 6, 2025 Page 2 of 11 Micross Adv. Interconnect Tech EPA ID# NCD018946590 7) Purpose of Inspection The purpose of this inspection was to conduct an unannounced compliance evaluation inspection to determine Micross Advanced Interconnect Tech compliance with the applicable requirements of RCRA and the corresponding NCDEQ regulations. This was an EPA lead inspection. 8) Facility Description Micross Advanced Interconnect Tech, LLC (Micross) is an ITAR-registered microfabrication facility that provides development, custom (flexible) prototyping and production services for customers. Micross offers advanced packaging and 3D integration solutions that enable higherperformance systems with decreased size, weight, and power (SWaP). Micross maintains government and aerospace contracts. Micross production is small quantity due to the specific nature of the customer specifications. The facility typically operates from 0700 to 1830 with approximately 100 employees including any tenants. The tenants are comprised of various independent companies sharing Micross resources including but not limited to the clean rooms, various labs, and equipment. At the time of the inspection, the facility was undergoing construction so previous operations and locations of clean rooms and waste storage may change or be added following the completion of the construction activities. The facility access is controlled with a locked front door and front desk administrator. The building consists of an office space, clean rooms (laboratories), laboratories containing specific equipment, and a basement housing the product storage tank and hazardous waste storage tanks. All clean rooms and most laboratories require personnel to dress in a full body suit, mask, shoe covers, and gloves. The building is maintained and managed by Micross; however, there are tenants which work closely with Micross. The tenants work on different steps in the production or development process along with Micross to develop a joined product. All waste produced in any area is managed by Micross. Production mostly consists of gold arsenic plating, etching, wafer bumping, and microchip connections. Micross operates as a large quantity generator of hazardous waste (with waste codes D001, D002, D003, D004, D005, D007, D008, D009, D010, D011, D035, F002, F003, F005, P098, U044, U070, U159, U219, U220) and large quantity handler of universal waste (Batteries, Aerosol Cans, Lamps, Mercury containing equipment) with the last notification being January 22, 2024. The facility generates six main hazardous waste streams. Three are managed under the Satellite Accumulation Area (SAA) and LQG Permit exemptions (Plating Waste, Solvent Waste, Lab Packs ), two are managed under the elementary neutralization exemption (Corrosive Waste), and one is managed as a recyclable material utilized for precious metals recovery. Hazardous wastes generated on-site that are managed under the SAA and LQG Permit Exemptions include plating waste, solvent waste, and lab packs. The plating production process generates spent acidic, corrosive, liquid, containing metals, a D002, D008, D011 hazardous waste, that is transferred through hard piping from the point of generation to the plating waste hazardous waste storage tank. The semiconductor production process generates spent mixed nonhalogenated ignitable solvents, a D001, D008, D035, F003, F005 hazardous waste, that is EPA-RCRA CEI Report March 6, 2025 Page 3 of 11 Micross Adv. Interconnect Tech EPA ID# NCD018946590 transferred through hard piping to the solvent waste tank. The lab packs are produced from lab waste, residual chemicals (with bottles), used contaminated personal protective equipment, and wipes used in the clean laboratories. Hazardous wastes generated on-site that are managed under the Elementary Neutralization Exemption include the main corrosive waste stream and a smaller Fluoride waste stream. The etching production process generates the main corrosive waste, a D002 hazardous waste, that is transferred through hard piping to the Corrosive Waste Storage Tanks. There are two corrosive tanks. One is the main tank, and one is managed as overflow. Each tank is capable of automatically neutralizing the liquid using Hydrochloric Acid or Sodium Ammonia. The pH of each tank is constantly monitored and displayed on the tank monitoring system in the basement. The sensors are assessed twice per year to ensure accuracy. The neutralized wastewater is sent to Durham County, pH is constantly monitored. The facility also produces Fluoride waste which is also corrosive and elementary neutralized. This is hand neutralized without mixers or probes and pH paper is used to identify the level of neutralization needed. This waste is then shipped offsite and not sent to the county for disposal. This is a smaller source of corrosive waste of approximately 300 gallons produced in six months. The facility also uses a bead-blast unit to clean equipment shields. Spent sandblasting material that is generated by this unit is managed as a recyclable material sent for precious metal recovery with gold being the precious metal. Micross' chemicals are stored in three explosive safe storage rooms. Each room contains a drain that is hard piped to the corresponding waste tank if a spill were to occur. The drain in the corrosive chemical storage room is hard piped to the corrosive waste tanks and the drain in the solvent chemical storage room is hard piped to the solvent waste tank. The Micross facility previously had four groundwater monitoring wells on the facility grounds; however, NCDEQ requested to remove and fill-in the wells as the wells have not been active in many years. Micross completed this activity on September 29, 2017. 9) Previous Inspection History North Carolina Department of Environmental Quality (NCDEQ) has conducted four RCRA CEIs at the subject facility between 2015 and 2024 and found no violations during those inspections. On September 17, 2021, NCDEQ conducted the most recent RCRA CEI at the subject facility and no apparent violations of RCRA's requirements were found. 10) Opening Conference EPA-RCRA CEI Report March 6, 2025 Page 4 of 11 Micross Adv. Interconnect Tech EPA ID# NCD018946590 On March 6, 2024, EPA inspectors Sarah Rowell and Laurie Benton, accompanied by NCDEQ inspectors Jenne Hughes and Angela Murphy, arrived at Micross at approximately 0900. Giao Nguyen, Environmental, Health and Safety Manager, immediately received the inspectors. The inspectors signed in using the automated system and with a name tag printed. A badge was also given to each inspector in order to badge in and out of rooms. Giao Nguyen and the inspectors were joined by Benn Sewell for the opening conference. The inspectors introduced themselves, showed their credentials to Giao Nguyen and Ben Sewell, and explained the purpose of the visit. The Small Business Regulatory Enforcement Fairness Act's classification of a "small business" is generally set by the Small Business Administration using the business' SIC/NAICS code and annual receipts or number of employees. A copy of the EPA's information sheet for small businesses can be found at https://www.epa.gov/sites/production/files/201706/documents/smallbusinessinfo.pdf. The EPA inspector discussed the company's ability, pursuant to 40 C.F.R. 2.203, to assert a business confidentiality claim for information submitted to EPA. The company stated that all production areas and a majority of the production processes are confidential. The inspectors described the anticipated use of equipment (digital camera) during the inspection and provided a request for records. Giao Nguyen and Ben Sewell provided an overview of the facility's history and current operations during the opening conference. The current operations were explained broadly as to not discuss confidential business information. The inspection participants also discussed health and safety protocols and required personal protective equipment before Facility representative led the inspectors on a tour of the Facility operations. 11) Inspection Observations Clean Laboratory - Satellite Accumulation Areas: Micross manages SAAs inside the Clean Room Laboratories and other laboratories surrounding the campus. Most liquid hazardous waste generated in these areas is hard piped to the associated waste tank (plating waste tank, solvent waste tank, or corrosive waste tank), but some liquid solvent and corrosive wastes are accumulated in a SAA before they are lab packed in the CAA. Containers in these SAAs were visible from the exterior laboratory windows. Due to the visibility of the SAAs and the requirements for PPE, the inspectors did not enter the clean rooms. Pictures were not taken of the SAA's as to not capture the equipment. On August 28, 2018, NCDEQ and Micross agreed to change out the trash cans in SAAs to add a step can with a rubber gasket securing the lid; the inspectors observed the new 5-gallon containers at all SAA locations in the laboratories. The inspectors also observed a spill kit next to most containers within the SAAs. The main Clean Laboratory is managed as one SAA, all waste generated is within the confines of the laboratory and collected in or transferred to the main breezeway of the main Clean Laboratory prior to being moved to the CAA. Even if all containers were full, the total volume of hazardous waste in all 5-gallon step cans, all 1-gallon waste product containers, and the 1-gallon solvent pickle jar amounted to less than 55-gallons. One 5-gallon container (step can) in the clean laboratories SAA was open, but otherwise labeled. In the main breeze way to the Clean Laboratories a SAA was located with waste in preparation to be lab packed. All EPA-RCRA CEI Report March 6, 2025 Page 5 of 11 Micross Adv. Interconnect Tech EPA ID# NCD018946590 other containers were equipped with a lid, which were secured, were marked as solvent or corrosive waste, labeled with appropriate waste codes, the words hazardous waste, and identified with a hazard indicator. The inspectors encouraged the facility, if the 55-gallon limit becomes regularly reached, to define distinct SAA(s) inside the lab, and treat the breezeway as a CAA so that they could continue the established standard procedure with the least amount of changes. Pursuant to 15A NCAC 13A .0107(a) [40 C.F.R. 262.15(a)(4)], which is a condition of the SAA Permit Exemption, a container holding hazardous waste must be closed at all times during accumulation. Central Accumulation Area (CAA): Micross also manages hazardous waste in the outdoor CAA. This area is partially bermed, covered, and supplied with an eyewash, shower, and spill kit. Also in the area are two metal storage cabinets and one large Conex-type container. The area was identified with a sign which read "danger, hazardous waste storage." Micross manages empty drums and the Lab pack waste stream in this CAA, and the inspectors observed "No Smoking" signs. At the time of the inspection, the CAA contained no waste. The most recent shipment was sent to Veolia Es Technical Solutions, LLC [NCD986166338] on March 4, 2025. Facility Area for Universal Waste Management: Micross manages universal waste lamps and batteries. All universal waste is stored in the CAA. The universal waste lamps are stored in the large Conex-type container in a four-foot round cardboard tube. The universal waste batteries are stored in the metal storage cabinet. According to the records provided during the inspection, the facility sends few shipments of universal waste offsite during a calendar year. The most recent shipment of universal waste lamps was sent to Veolia Es Technical Solutions [NCD986166338], where Micross regularly ships universal waste and lab packs, on March 4, 2025. The inspectors did not observe any container(s) of universal waste as the shipment had just been sent out the week prior. Basement: On the bottom floor of the facility, sits the hazardous waste tanks, elementary neutralization units, product tanks, a sandblasting machine, and the DI water system. Micross manages one plating hazardous waste tank, one solvent hazardous waste tank, one fluoride elementary neutralization unit (tank), two elementary neutralization units (tanks), and two product tanks (Hydrochloric Acid and Sodium Ammonia). All tanks were observed and were labeled and in good condition. The Solvent Tank is located outdoors in a walled area, no roof, and a closed drain. All other tanks and equipment on this floor are located indoors. The plating waste tank was approximately one third full. The inspectors observed the fluoride elementary neutralization unit. At the time of the inspection, the tank held the corrosive only waste until able to be neutralized with Sodium Ammonia and sent out as non-hazardous waste. The tank contained approximately 200 gallons at the time of EPA-RCRA CEI Report March 6, 2025 Page 6 of 11 Micross Adv. Interconnect Tech EPA ID# NCD018946590 the inspection. The inspectors observed the two other elementary units. The pH was being monitored for both tanks and the waste being sent to the county. At the time of the inspection, the pH was approximately seven for all monitoring points. The Sandblasting equipment was observed. Giao Nguyen explained there a piece of the equipment used in the plating production process that accumulates precious metal (Gold). The equipment is taken apart, the pieces of the equipment are sandblasted, and the sandblasting grit is sent for precious metal recovery. The precious metal recovery records were requested as part of the record review. 12) Records Review Records Review The facility maintained organized records. The facility was able to address questions and facilitate necessary records with ease. Contingency Plan and Quick Reference Guide (QRG): The actions that facility personnel should take in response to an emergency are described in the facility's Contingency Plan. The existing plan was in the process of being updated to reflect the ongoing construction activities. Completion of the contingency plan update was not anticipated until the construction plans and activities are finalized. The plan describes actions facility personnel must take in response to fires, explosions, or any unplanned sudden or non-sudden release of hazardous waste or hazardous waste constituents to air, soil, or surface water at the facility. The plan describes arrangements agreed to with the local police department, fire department, other emergency response teams, emergency response contractors, equipment suppliers, local hospitals or the Local Emergency Planning Committee. The plan lists the names and emergency telephone numbers for persons identified as emergency coordinators. Giao Nguyen is listed as the primary emergency coordinator, and the other individuals are listed in the order in which they will assume responsibility as alternates. Ben Sewell had not been included in the updated plan. Ben Sewell was a newly hired employee replacing, Al Mason, who retired in December 2024. Due to the active editing of the Contingency Plan, the inspectors noted this as an area of concern. The plan includes a list of all emergency equipment at the facility. The list includes fire extinguishing systems, spill control equipment, communications and alarm systems, and decontamination equipment. The list appears to be up to date. The plan includes the location and a physical description of each item on the list, and a brief outline of its capabilities. The plan includes an evacuation plan for personnel. This plan describes signal(s) to be used to begin evacuation, evacuation routes, and alternate evacuation routes. EPA-RCRA CEI Report March 6, 2025 Page 7 of 11 Micross Adv. Interconnect Tech EPA ID# NCD018946590 A copy of the Contingency Plan (and its quick reference guide) was most recently submitted to the police department, fire department, hospital, State and local emergency response teams and the Local Emergency Planning Committee on May 27, 2021. There are no new waste generation points, waste management areas, or emergency coordinators. The facility has not submitted the Contingency Plan more recently since the facility is continuing updating the draft of the plan and will submit it once the construction is complete. The fire department had recently inspected the facility due to the ongoing construction and reclassification of the building the facility had also provided the planned renovation map and other requests the fire department needed. The quick reference guide was last updated January 2025 and includes the types/names of hazardous waste in layman's terms and the associated hazard associated with each hazardous waste present at any one time; the estimated maximum amount of each hazardous waste that may be present at any one time; the identification of any hazardous wastes where exposure would require unique or special treatment by medical or hospital staff; a map of the facility showing where hazardous wastes are generated, accumulated and treated and routes for accessing these wastes; a street map of the facility in relation to surrounding businesses, schools and residential areas; the locations of water supply; the identification of on-site notification systems; and the name of the emergency coordinator(s) and emergency telephone number(s). All maps included in the quick reference guide were clear and easily understood in sizes to be read. The maps included multiple examples of where the hazardous materials are kept, the nearest exits with corresponding arrows, and instructions based up the emergency concern. Since the facility maintains Cyanide and other chemicals that may need special or unique requirements, the facility also maintained the unique instructions. Training Records: The inspectors reviewed facility job descriptions and employee names that were provided for Giao Nguyen [Health and Safety Officer], Stephen Hall [Engineer], Ben Sewell [Facility Maintenance Engineer] and Tim Hedgepeth [Facilities Manager], Rex Anderson [Director of Operations], and Al Mason [Previous Facility Maintenance Engineer] who retired. Each description included the requisite skill, education, or other qualifications, and duties of facility personnel assigned to that position. Micross provided a written description of the type and amount of both introductory and ongoing training to be given to each person filling the positions listed above. The inspectors reviewed records of employee hazardous waste training completed in 2022 - 2025 Calendar years. Waste Manifest and Land Disposal Restriction (LDR) Records: The inspectors reviewed available hazardous waste manifest records and land disposal restriction forms for shipments of hazardous waste sent since the calendar year 2022. The EPA-RCRA CEI Report March 6, 2025 Page 8 of 11 Micross Adv. Interconnect Tech EPA ID# NCD018946590 hazardous waste manifest records were organized by waste stream: Lab Packs, Plating Waste, and Solvent Waste. Records demonstrate the plating wastes [D002, D008, D011] are routinely shipped to Ecoflo Inc. [NCD980842132], and the most recent shipment was made on March 12, 2025. Records demonstrate the solvent waste [D001, D035, F003, F005] is routinely shipped to US Ecology [MID074259565] and the most recent shipment was made on February 25, 2025. Records demonstrate the lab packs [D001, D002, D003, D004, D006, D008, D011, D035, F003, F005] are routinely shipped to Veolia Es Technical Solutions [NCD986166338], and the most recent shipment was made on March 4, 2025. The inspectors observed a manifested shipment [001065548 WAS], dated July 14, 2022, with the generator being Brenntag Mid-South Inc. [ND047372503], a company that supplies Micross with bulk chemicals (HCl). According to Giao Nguyen, a shipment of HCl that was supplied by Brenntag Mid-South began foaming and showing evidence of impurities while filling Micross's product storage tank. Micross rejected the shipment, emptied the contents of the storage tank, and performed necessary steps to clean the HCl Product tank. Brenntag Mid-South accepted responsibility for generating the contaminated HCl Product that was rejected by Micross and the waste generated from the tank cleaning activities but refused to send personnel to the Micross facility to sign the hazardous waste manifest. As a result, Giao Nguyen signed the manifest for D002 hazardous waste generated by Brenntag-Midsouth at the Micross facility and sent to Ecoflo Inc. [NCD980842132]. The TSD facility subsequently determined that the HCl had been contaminated with heavy metals (AL, Cu, Fe) and nitric acid. The supplying facility had an apparent internal investigation regarding the matter. This was noted as an area of concern for the inspectors. Waste Profiles The inspectors reviewed the waste profiles of the three waste streams. The plating waste stream was reviewed to confirm the contents of the and the in consistencies in the LDR forms sent in the manifests. At the time of the inspection, the waste profiles accompanying the manifests included Cadmium, Chromium, Nickel, and Methanol in the underlying hazardous constituents list but were not included in the LDR form. At the time of the inspection, Micross immediately contacted the company managing the LDR forms to receive more detail regarding the missing underlying hazardous constituents. The inspectors requested this be a deliverable after the inspection. Pursuant to 15A NCAC 13A .0107(a) [40 C.F.R. 268.7(a)(2)], if the waste does not meet the treatment standards, with the initial shipment of waste to each treatment or storage facility, the generator must send a one-time written notice to each treatment or storage facility receiving the waste and place a copy in the file. The notice must include the information in column "268.7(a)(2)" of the Generator Paperwork Requirements Table in paragraph (a)(4) of this section. The list of required information found in column 268.7(a)(2) includes the constituents of concern for F001-F005, and F039, and underlying hazardous constituents in characteristic wastes. EPA-RCRA CEI Report March 6, 2025 Page 9 of 11 Micross Adv. Interconnect Tech EPA ID# NCD018946590 Weekly Inspection Records The inspectors reviewed Micross' available records of inspections of the hazardous waste central accumulation area (CAA) since calendar year 2022. For all inspection records reviewed, the facility completed inspections every Monday and Friday. The inspection log includes a checklist to record observations about leaking containers and about deterioration of containers caused by corrosion or other factors. The inspection log includes a checklist to record observations such as: aisle space, visible container labels, legible container labels, complete container labels, closed lids and bungs, material on outside of container, rings tight, rings turned down, condition of containers, containers compatible with waste, container grounding, control of ignition sources, container stacking, container storage time, contents of containment units, housekeeping, emergency communication, fire extinguisher, spill response kit, and salvage drums. The records include the date and time of the inspection and the name, signature and initials of the employee conducting the inspection. Employees do routinely record inspection observations and subsequent follow-up actions on the inspection log. Organic Air Emission Monitoring Records (Subparts BB) The inspectors reviewed Micross' available records of organic air emission monitoring for the tank systems since calendar year 2022. Micross only has three points of monitoring as the whole system is almost entirely welded since November 11, 2008, and only monitor Subpart BB annually. The un-welded portions are only three valves [Valve #1, Valve #2, Valve #3] and the inspections were annual. Micross explained the possibility for changes after completion of the construction. The inspection log includes a checklist to record observations regarding leaks and deterioration caused by corrosion or other factors. The inspection log includes a checklist to record observations. The records include the date and time of the inspection and the name, signature and initials of the employee conducting the inspection. Employees do routinely record inspection observations and subsequent follow-up actions on the inspection log. The facility even notes information regarding the product tanks and the DI water system. Precious Metal Recovery Records Micross sandblasts the inner pieces of equipment and sends the sandblasting material to Advanced Chemical Precious Metals and Refining in Rhode Island. The records for the transactions were reviewed. The precious metal the facility recovers is gold from the gold plating manufacturing process. The most recent shipment was from July 2024. Tank Records: Micross manages two hazardous waste tanks, three elementary neutralization tanks, and two product tanks. The inspectors reviewed the Tank Assessments, Tank Design and Installation Certifications, and Daily Inspection Records. Both hazardous waste tanks were double walled and appeared to be in good condition. 13) Closing Conference EPA-RCRA CEI Report March 6, 2025 Page 10 of 11 Micross Adv. Interconnect Tech EPA ID# NCD018946590 The inspectors conducted the exit meeting at approximately 1600 with Giao Nguyen. During this meeting, the inspectors stated their preliminary conclusions of the inspection. Micross had provided all records requested at the time of the inspection. The inspectors requested additional information to explain the observations regarding the LDR records. At the time of the inspection, the facility was awaiting the response. 14) Signed SARAH ROWELL Date: 2025.05.12 23:23:47 -04'00' Digitally signed by SARAH ROWELL Sarah Rowell Environmental Engineer 15) Concurrence ARACELI CHAVEZ Date: 2025.05.13 13:16:32 -04'00' Digitally signed by ARACELI CHAVEZ Araceli B. Chavez RCRA Enforcement Section EPA-RCRA CEI Report March 6, 2025 Page 11 of 11 Micross Adv. Interconnect Tech EPA ID# NCD018946590