I Wexal In ternat ional Li m ited.

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1 M E M O R A N D U M DATE: 06 August 1999 TO: Each Board Member FROM: Becci Cantrell RE: Application for PC licence from Wexal nternational Ltd., Reg. No. 394 Name of applicant; Location of activity: Class of activity: Licence application received: Section 97 Notice sent Notices under article 11 issued: nformation under Article 11 received: Section 97 reply received Submissions received: Wexal n ternat ional Li m ited. 1 Dublin Road, Enniscorthy, Co. Wexford.! processing of non-ferrous metals with a batch i capacity exceeding 0.5 tonnes. 3 i 91319a. j i 8/5/98. ; a ma, 26/3/99, , /8/99. None. Company Wexal nternational Ltd. was established in 1977 and was formerly known as Penn Aluminium nternational Ltd. The parent company is based in Holland and USA. t is a major supplier of precision drawn aluminium tubing to the automotive industry, the main product being heat exchanger tube. The company has the capacity to produce 4,500 tonnes of product per year and are currently operating at 3,500 tonnes. There are 157 employees. The plant operates 24 hours per day using a three shift system with a special weekend shift. The plant is closed for one week in the summer and winter for maintenance. The company is accredited to S and QS 9000 and is in the process of applying for accreditation to S Process Description The process involves heating solid aluminium in a furnace to form tubing by extruding it through a die. The tubing is subsequently sized, hardened, cut and cleaned to customer requirements. Bars of solid aluminium (billet) are heated in the extrusion press and pushed under high pressure (1,650 ton) through a tube or profile die. Tube dies give the starting size for coiled tube and profile dies are used for cut long length sections. The hot extruded aluminium is cooled in a bath of water. Most of the tubing is then lubricated and drawn down to a smaller size by pulling the coil through a die (draw block). A hydrocarbon solvent is used in the final draw to clean the tube. The hardness tempers are adjusted to customer requirements. Tubing is rolled into the annealing furnace and heated to 450 C or age hardened in a 1

2 furnace heated to 200 C. Some tubing is produced in coils but the bulk of tubing goes to make heat exchanger tube which is straightened and cut to a specified length. The cutting process uses four saws which leave saw chips on the tubing. The tubes are then dipped in baskets into tanks containing solvent to remove saw chips and oil from the tube. Trichloroethylene (TCE) is the main degreasing solvent used. A mixture of Alpol 40 and Alpol Eva is also used to a lesser extent. Both Alpols are paraffin hydrocarbons. Waxes and esters are added to the latter. The degreasing unit consists of a hot and cold TCE tank and an Alpol tank. The Alpol mixture acts as a degreaser but also leaves an oily residue which acts as a pre-lubricated finish. t is currently used for a small percentage of the work as per customer requirements. Finally, tubes are inspected and packed for distribution. Ancillary processes include a caustic bath to remove aluminium from used dies. Extrusion dies go through a nitride process to harden the surface which lengthens their lifespan. This involves heating the dies in a furnace to 500 C with ammonia. Proposed Determination Air: There are two main emission points from the degreasing unit. Minor emissions consist of those from the annealing furnace, ageing furnace, caustic bath area and degreasing area. There are no boiler emissions. Degreasing Unit The highest emissions are from the vent above the hot TCE tank (A2-1). nitial monitoring results of TCE emissions for samples taken on 3/2/98 were 1,378 mg/m3 at a mass flow of 9.48 kg/hr. A number of measures were taken to reduce the level of TCE emitted including better operational practice and covering the tank whenever possible. Subsequent monitoring on 27/10/98 gave much lower results with a maximum of 339 mg/m3 at a mass flow of 2.25 kg/hr. The T.A. Luft emission limit value for Class substances is 20 mg/m3 at a mass flow of kg/hr. Air dispersion modelling showed that emissions using the more recent monitoring results predicted a maximum one hour ground level concentration of TCE of 849 pg/m3 off-site at a distance of 400 metres north west of the stack. The stack height is 7.9 metres above ground level and is 2.8 metres below the apex of the adjacent building. The ground level concentration is below the former WHO 24 hour average guideline value of 1 mg/m and the Occupational Exposure Limit (OEL) divided by 40 of 13.4 mg/m3. t is not below the Danish C- value of 200 pg/m. The current WHO figure of 4.3 x lo- pg/m3 UWlifetime figure which refers to a lifetime exposure of 1 pg/m3. The average annual ground level concentration is 30 pg/m. t is proposed to set a limit of 2.30 kg/hr until 31 December 1999 after which date TCE is required to be eliminated from the process. Monitoring results of emissions from the Alpol cleaner (A3-3) were 29 mg/m3 at a mass flow of 0.46 kg/hr. This solvent is classified as mainly paraffin and naptha hydrocarbons. The T.A. Luft limit for Class ll substances (150 mg/m3 at a mass flow of 2 3 kg/hr) is proposed as the emission limit value for A3-3. Emissions from the Alpol cleaner are expected to increase in the future as TCE is phased out. The company is required to resample air emissions after changes are made in the degreasing unit (Condition 5.5). 2

3 Fugitive emissions include TCE, oil mist and white spirits. The reduction of fugitive emissions is required to be addressed under the Schedule of Environmental Objectives and Targets. An occupational hygiene survey in the work area showed that the exposure of employees to these substances did not exceed the OEL and the levels within the workplace are acceptable. Process Effluent: Approximately 3.7 m3/day of trade effluent is currently discharged to sewer in addition to domestic effluent. This comprises rinse water from the caustic die cleaning and floor washings. The die rinse contains aluminium sulphate and investigation is underway as to its re-use in waste water treatment plants. t is planned to discharge 2m3/day of steam cleaning water to sewer which currently discharges directly to surface water. The company also requested to discharge cooling water to sewer. However, it has been indicated that the Sanitary Authority may not agree to accept this due to the large hydraulic load. Provisions have been made in the PD for the discharge of cooling water to surface water. A maximum temperature limit of 25 C is proposed for cooling water discharged from the site to ensure that the temperature of the receiving water is not adversely affected. All effluent is directed through a septic tank, Klargest Bio-filter unit and a settlement tank prior to discharge to sewer. However, monitoring results show that the biofilter system is not effective in treating the effluent. The result of an acute toxicity test (Microtox) carried out in 1998 at the foul sewage outlet which included the die rinse, floor washings and domestic effluent was The sewer ultimately discharges to the River Slaney downstream of Enniscorthy via St. John s treatment works where it undergoes secondary treatment. Limits will be proposed in accordance with the consent conditions issued by Wexford County Council under Section 97. Surface Water: There are two channels discharging to surface water. Yard runoff and cooling water flows through one interceptor system and roof run-off through another. The channels join after each interceptor and discharge off-site to an underground drain. This drain discharges into the River Urrin at a distance of approximately lkm which is a tributary of the River Slaney. The lower reaches of the River Urrin are classified as slightly polluted (1995 data). Cooling water from the extruded aluminium system discharges at a rate of 432 m3/day to surface water. A production well on-site supplies half of the cooling water requirements, the other half is supplied by the mains. Monitoring results show a high nitrate concentration (6.3 mg/l as N) and some contamination by trichloroethene (14 pg/) and cis 1,2-dichloroethene (7 pg/l). Monitoring results for the storm water discharge (cooling water, yard and roof run-off) indicate contamination by cis 1,2-dichloroethene (242 pg/), trichloroethene (82 pg/l) and vinyl chloride (49 pg/l) and lower concentrations of other organic compounds. An acute toxicity test was carried out in 1998 for Daphnia Magna and Microtox. The results were < 1 and < 2.2 respectively. Trichloroethylene is classified as a List substance under the Dangerous Substances Directive 76/464/EEC. Levels recorded in surface water emissions are within the limits specified for emissions to waters from the use of 3

4 trichloroethylene for degreasing metals of 100 pg/, contained in Article 5 of D i rect ive 8 6/2 8 O/E EC. The company will be required to eliminate any surface water contamination under the Schedule of Objectives and Targets. Weekly and quarterly monitoring is proposed in Schedule 5(i) with daily visual inspections of surface water discharges. Cooling water emission limits for ph, temperature and COD are proposed in Schedule 2(i). Condition 6.3 requires the cooling water to be screened for the presence of organic compounds within three months and thereafter as required by the Agency. All interceptors on-site are required to be maintained and inspected under Condition Groundwater: Previous site investigations have shown that the groundwater beneath the site is contaminated with trichloroethylene. The main source of this contamination is the degreasing unit. The yard area was also found to be contaminated with hydrocarbons as all discharges went to ground prior to 1995 before interceptors were installed. Contaminated soil was excavated from this area in the past as part of remedial works on-site. The bedrock beneath the site consists of rhyolites in slaty mudstones (Campile Formation) which is classified as a regionally important aquifer. A production well on-site supplies half of the cooling water requirements, the other half is supplied by the mains. Monitoring results from the well show a high nitrate concentration (22mg/l as NO3) and contamination by trichloroethylene (77 pg/l)and cis 1,2-dichoroethene (29 pg/l). Subsequent monitoring results show lower concentrations of 21 pg/l and 7 pg/l for the organic compounds respectively. A comprehensive investigation into the extent of soil and groundwater contamination is required under Condition This is to include a risk assessment and proposals for any necessary remediation. Waste: Hazardous waste produced on-site consists of waste oil, trichloroethylene, solvent, caustic, fluorescent tubes and contaminated rags. Aluminium swarf (chips blown from the saws), packaging and general waste are handled by agreed waste contractors. Scrap aluminium generated during the process is baled and sent to suppliers for melting and is remade into billet. Noise: The site is located at the northern end of an industrial estate outside Enniscorthy. t is adjacent to agricultural land and some residential houses. The nearest noise sensitive location is a residence located 14 metres from the eastern boundary of the site. A noise survey carried out in 1998 show noise emissions from the facility to be within Agency guidance on noise at the nearest noise sensitive ocat i on. Class, List and / Substances: Substances classified as List or List according 4

5 to either the Dangerous Substances Directive (76/464/EEC) or Groundwater Directive (80/68/EEC) used on-site include TCE, Alpol solvent, lubricant and hydraulic oils. TCE is a T.A. Luft Class 1 substance. Alpol is a T.A. Luft Class ll substance. TCE is to be eliminated from the process by 1 January, Submissions: No submissions were received in relation to this application. Recommendation That the Board approve the Proposed Determination as submitted..- w Rebecca Cantrell nspector, Licensing and Control