Charles K. Ashbaker January 25, 1988
APPLICANT; Teledyne Wah Chang Albany - NPDES Permit Renewal P.O. Box 460 Albany, OR 97321 Application No.: OR 000111-2 Received June 10, 1981
FACILITY DESCRIPTION:
Teledyne Wah Chang Albany (TWCA) operates a primary zirconium- hafnium, primary columbium, and primary and secondary titanium manufacturing facility as well as a zirconium-hafnium, titanium, and refractory metals forming facility in Millersburg, Oregon near Albany. The facility discharges treated process wastewater to Truax Creek which makes its way to the Willamette River via Murder Creek, Third Lake and Fourth Lake (Conser Slough).
PRODUCTION OPERATIONS:
The major manufacturing operations' performed at TWCA are for the production of zirconium.
They are currently receiving zircon sand (ZrSi04) from Australia which has already had rutile and ilmenite removed through an ore dressing process. Through the process of sand chlorination," the zirconium in the sand is changed to zirconium tetrachloride (ZnC.14) . Small quantities of hafnium tetrachloride (HfC14) are found within ths zirconium tetrachloride. These compounds are dissolved in water to form the respective oxychlorides and filtered to remove unwanted solids.
Through a chemical separation process, using ammonium thiocyanate and Methylisobutyl ketone (MIBK), the zirconium is separated from the hafnium. Sulfuric acid and ammonium hydroxide are added to the solutions to form precipitates. Through individual calcining steps, zirconium oxide and hafnium oxide are formed. Then, after a second chlorination to form pure ZrCl4 (or HfC14), metalic sponge is formed through a reduction process. This sponge is later blended with various alloying elements and melted to arrive at desired alloy compositions.
In addition to the zirconium and hafnium, TWCA also produces columbium, tantalum, vanadium, and titanium.
Although most of the pollutants in the wastewater stream come from the sand chlorination and chemical separation processes, there are minor quantities which come from melting, casting, and forming processes which also take place on site.
WASTEWATER TREATMENT AND SLUDGE DISPOSAL:
The primary wastewater treatment system consists of chemical recovery, waste stream neutralization, chemical precipitation and sedimentation. This produces a metal hydroxide sludge. Sludge generated over the last few years has been held in surface impoundments. Because of the small quantity of natural radioactivity in the sludge, it's disposal has been quite controversial. At one time it was spread on land as a soil amendment. Some of the ponds are in the flood plane of the Willamette River and may eventually be moved to higher ground. . This is a Superfund project handled out of our Hazardous Waste Section. Therefore, sludge disposal will not be addressed in this permit. All new sludge generated goes through a process for removing the radioactive elements.
Other treatment processes consist of a dechlorination system to reduce residual chlorine and the associated toxicity, a thiocyanate regeneration system, an ammonia recovery system, a boildown system for production of an ammonium sulfate liquid fertilizer from the dilute ammonium sulfate waste,, oil separation systems, MIBK steam stripping systems, and a barium sulfate coprecipitation system for reduction of radium. An emergency holding and neutralization system is also available.
STORMWATER:
Much of the area around TWCA is not paved and most stormwater will seep into the ground. The paved areas in the vicinity of the sand/pure chlorination, acid cleaning, and chemical processing areas all drain to the wastewater treatment system. Some of the storm drainage in the forming and fabrication areas is discharged to a storm sewer which goes to Murder Creek.
In order to reduce the quantity of water treated in the wastewater treatment system, some of the roof drains and other stormwater not contaminated with processes or chemicals could be diverted directly to surface streams. Any stormwater which has a reasonable potential for chemical contamination should continue being discharged to the treatment system. There are no apparent areas which are now discharging directly to public waters but which need to be diverted to the treatment system.
The EPA recommended that all stormwater, along with cooling water blowdown and other unregulated waters, be diverted to a separate treatment system. A better alternative might be to put a condition in the permit which requires separation of non- contaminated stormwater streams from those which are contaminated so that the non-contaminated stormwater could discharge directly to the receiving stream. This is being required in the permit.
OTHER NON-PROCESS WASTEWATER STREAMS:
TWCA operates 12 cooling water systems in the manufacture of its nonferrous metal products. The blowdown from four of these systems presently discharge directly to surface waters. No treatment is necessary for these streams. The discharge from these systems has not been addressed by permit in the past. They will be referred to as outfalls 002, 003, 004, and 005, respectively.
If other cooling systems sources were discharged directly to surface streams there would be an increase in the efficiency of operation of the Central Treatment System due to a reduction in flow. It would also add additional sources of non-contaminated water to the receiving stream. This is desirable. The diversion of the water from some of these systems may need to include a failsafe gate and switch which could divert them to the treatment system in the event of a heat exchanger failure. A condition will be put into the permit requiring the permittee to submit plans for approval by,the Department for separation of cooling water discharges from the Central Wastewater Treatment System.
PERMIT STATUS:
The last NPDES permit was issued to TWCA October 31, 1978, The permit was contested by the applicant and a hearing.was requested before the deadline expired so th'at they would not lose their ability to contest the permit in the event they could not meet the limits. However, they were not in a hurry to pursue the hearing so, by mutual consent, one was not scheduled. The permit was considered valid. They were able to achieve substantia^ compliance and the contested case was never pursued by either party.
The permit expired July 31, 1981, but has remained in effect pending the issuance of a new permit. Since EPA was in the process of promulgating effluent guidelines for the category of " industry unique to TWCA, the Department was not anxious to proceed with a permit renewal. The decision was made to delay the renewal of the permit until the effluent guidelines were promulgated.
EPA was asked to develop guidelines for those processes employed at TWCA. Because of the limited number of sources which are comparable to TWCA, EPA suggested that, rather that promulgating guidelines, it might be preferable for them to draft the TWCA permit using best professional judgement. The Department was agreeable to either procedure. The effluent guidelines affecting TWCA were eventually developed and promulgated. The EPA provided the Department a draft permit for TWCA based on these effluent guidelines for regulated waste streams and based on best professional judgement for those waste streams not covered by the guidelines.
CURRENT PERMIT LIMITS:
The following limits appear on. the permit which was issued October 31, 1978, and which are currently in effect:
Parameters Loadings (lb/day) monthly average daily max
Ammonia Nitrogen 4 00 8 00 Thiocyanate ion 3 50 700 Methylisobutyl Ketone (MIBK) 100 200 Total suspended solids (TSS) 300 600
Other Parameters Limitations pH Not outside the range 6 to 8 Oil and Grease Shall not exceed 10 mg/1 Total residual chlorine Shall not exceed 0.2 mg/1 Toxicity The 96 hour TLm shall not be less
than 25% effluent by volume at a pH Of 6.5 to 7.5.
At the time this permit was written, the production of total oxides at the facility were in the range of 40,000 pounds per day. An additional set of limits were included in the permit for
production in excess of 50,000 pounds per day. They were never needed because the market softened and the production went down rather than up.
COMPLIANCE HISTORY:
Back at the time the permit was issued in 1978, the permittee was having difficulty meeting the limits. The treatment system, • particularly the ammonia recovery system, was very near capacity and any minor upset would cause effluent violations. After the production was reduced, there was no difficulty in meeting the limits. The current production is in the range of 20,000 pounds of total oxide per day. There were two minor effluent violations in 1985. There were no effluent violations in 1986 and there have been none to date in 1987.
TOXICITY:
From the point of discharge in Truax Creek to the Willamette River, the receiving stream was devoid of aquatic life for many years because of the ammonia, cyanide, and chlorine in TWCA's effluent. Since the completion of improvements in the wastewater treatment system in 1978, the condition has improved immensely. Now, most 96 hour static bioassay results from TWCA show 100% survival of salmonids in 100% effluent. Some aquatic life has returned to Truax Creek.
TWCA is expected to reduce the flow of wastewater by improvements in recycling, diversion of non-contact cooling water, and diversion of non-contaminated cooling water. Since this will produce a more concentrated waste stream, it is probable that the waste stream
will become more toxic. This will be closely monitored by TWCA through the use of bioassays. In addition, the wastewater needs to be evaluated with respect to chronic toxicity. It is recommended that a new chronic toxicity bioassay be required by the permit.
During summer months the flow in Truax Creek is almost entirely TWCA treatment system effluent. Little or no flow enters TWCA property from upstream sources. Some overflow from the water supply storage area enters Truax Creek a short distance above the 001 outfall.
During an inspection on September 29, 1987, Blue Gill Sunfish were observed feeding in Truax Creek within 100 feet downstream from the outfall, The creek also had a good variety of fixed algae and water weeds growing on the bottom. There is also an algae growth on the bottom of treatment ponds 1 and 2.
POINT OF DISCHARGE:
For many years the permittee has wanted to discharge directly to the Willamette River rather that going to Truax Creek. The Department has been resistant to this for two reasons. First, the creek could act as a buffer between the discharge and the river and could provide additional treatment. Other beneficial uses of this intermittent creek have long since disappeared. Second, the mill site has been "contributing aslnuch or more ammonia to the creek from non-point sources as it has from the outfall. If the outfall had been changed to discharge .directly to the Willamette, there would still have been several hundred pounds per day of ammonia going to the creek from non-point sources. Therefore, it was decided to keep all of the waste sources together.
The amount of non-point contribution has dropped from about 700 pounds per day to less than 200 pounds per day. Once the non- point contribution has dropped to near background levels, consTderation can ce given tTo" a change in out tail location.
During summer months, almost all of the flow in Truax Creek comes from TWCA, There is a large quantity of dissolved solids in the discharge which may cause the total dissolved solids in the mixing zone, Conser Slough in particular, to exceed levels which can be used for irrigation. The permit should require TWCA to conduct a special monitoring study of the mixing zone.
RATIONALE FOR EFFLUENT LIMITS:
The Environmental Protection Agency has promulgated guidelines for portions of the primary zirconium and hafnium industry. In addition, they have proposed other parameters which need to be regulated at TWCA. The pollutants which they have determined need to be regulated in the TWCA permit are chromium, copper, cyanide, lead, nickel, zinc, ammonia, titanium, fluoride, molybdenum, radium, oil and grease, thiocyanate ion, methylisobutyl ketone, total residual chlorine, pH, and total suspended solids.
The parameters to be regulated can be categorized into three general groups; toxics, conventional pollutants, and non- conventional pollutants. The toxics include chromium, copper, total cyanide, lead, nickel, and zinc. The conventional pollutants include pH, total suspended solids (TSS), and oil & grease. The non-conventional pollutants include ammonia, fluoride, molybdenum, titanium, and radiura-226. Although radiurn- 226 was not included in the promulgated guidelines and it has not been regulated in the permit before, EPA is recommending that it be regulated since it is a recognized pollutant in their waste stream and they have a treatment system for reducing it's levels in the sludge.
EPA has used the building block method of establishing proposed effluent limitations for those parameters which require regulation because of promulgated guidelines. For example, cyanide is*listed as a parameter to be regulated in three of the various stages of the TWCA process. To build an effluent limit for cyanide one must add the allowable discharge from each of the three processes. For those parameters for which specific guidelines have not been promulgated, an effluent limit has been established based upon efficient use of the treatment processes used by TWCA.
RECOMMENDED LIMITS:
Those limitations and monitoring requirements developed by EPA are found in Table 1, attached. The monthly average limitations for those parameters expected to be found in surface runoff are based upon three separate levels or tiers of stormwater runoff which are based upon average daily rainfall levels ranging from less than 0.5 inches/day to more than 1.5 inches/day. The daily" maximum effluent limitations have been based upon four tiers of rainfall ranging from 0.5 inches/day to 2.5 inches/day. Other parameters have not been divided into different tiers.
Because of the difficulty in tracking and determining compliance with so many variations of allowable effluent discharges, the Department is recommending that only two sets of limits be incorporated into the permit, a summer limit (May 1 - Oct, 31) and a winter limit (Nov. 1 - April 30). This will account for most of the variations in rainfall, it will parallel other permits which have been written in Oregon, and it will be much easier to track. The monthly average discharge limits for summer months will incorporate the tier 1 levels recommended by EPA. That would be based upon average rainfall during the month of less that 0.5 inches per day. The daily maximum discharge limits would be^based upon the tier two levels. That would recognize that some rainfall events during the summer of up to 1.5 inches/day might occur. The monthly average discharge limits for winter months will follow the tier 3 levels which are based upon average rainfall during the month of over 1.5 inches/day. The daily maximum discharge^limits for the winter months would be based upon tier 4 levels which would recognize that some rainfall events of greater that 2.5 inches/day might occur.
Based upon the above discussion, the following effluent limitations are proposed:
1- Waste Discharge Limitations not to be Exceeded After Permit Issuance Date:
Outfall 001 (Central Treatment System)
Year Around Loadings
Parameters Monthly Ave, fib/day) Daily Max. (Ib/dav: Ammonia Nitrogen (NH3) 4 00 800 Thiocyanate Ion 350 700 Methylisobutyl Ketone(MIBK) 100 200s
Other Parameters Limitations Oil & Grease Shall not exceed 10 mg/1 Total Residual Chlorine Shall not exceed 0,2 mg/1 pH , Shall not be outside the range 6-9.0 Toxicity The 96 hour TLm shall not be less the
50% effluent by volume at a pH of 6.5-7.5.
Seasonal Loadings
Parameters (May 1 - Oct 31) Chromium Copper Cyanide(total) Lead Nickel CJ XxlC
Titanium Total Suspended Sol
(Nov 1 - April 30) Chromium Copper Cyanide(total) Lead Nickel Zinc Titanium Total Suspended Sol
Monthlv
ids(TSS)
idsCTSS)
Ave
310
335 9
'lb/day) 7
11. 3 6. 0
14 .1 7.4
Fluoride (F) 18.4 41.2 Molybdenum 1.5 3.4
(Outlet Residual Handling Treatment System)
Limitations Radium shall not exceed 20 pCi/1
Outfalls 002, 003, 004, and 005 (Cooling Tower Blowdown)
Parameters Limitations pH Shall not be outside the range 6 - 9 . Chlorine Shall not exceed 0.5 mg/1 Other Pollutants No biocides or water treatment chemicals
containing chromium, copper, zinc, chlorinated phenols or other priority pollutants shall be discharged.
The limits for.ammonia, thiocyanate ion, MIBK, oil & grease, and total residual chlorine are the same as the previous permit.
The pH of outfall 001 has been changed from 6 - 3 to 6 - 9. Originally, the upper pH limit was kept to 8 or less because of the increased toxicity of ammonia at the higher pH. Now, since the demonstrated toxicity of the effluent is low, the pH limit will be raised to the more common value of 9. For the metals removal treatment process to be efficient, a higher pH is preferred.
The limits for fluoride, molybdenum, and radium are based upon the recommendations of EPA.
The limits for TSS are based upon the previous permit plus an additional allowance proposed by EPA at their recommended outfall 002.
The summer monthly average limits for cyanide and the remaining metals are based upon EPA's Tier 1 for average rainfall <.5 inches/day.
The summer daily maximum limits for cyanide and the remaining metals are based upon EPA's Tier 2 for maximum daily rainfall up to 1.5 inches/day.
The winter monthly average limits for cyanide and the remaining metals are based upon EPA's Tier 3 for average rainfall exceeding 1.5 inches/day.
The winter daily maximum limits for cyanide and the remaining metals are based upon EPA's Tier 4 for maximum daily rainfall exceeding 2.5 inches/day.
I am recommending that 25% as required by the 50% means that there mu species in 50% effluent must be maintained with demonstrated toxicity o (100% survival in 100 some of the clean water treatment system is sti toxicity limit to the m the point of the curren
the toxicity limit be changed from a TLm of existing permit to a TLm of 50%. A TLm of st be at least 50% survival of the test
This is also the stream standard which in the mixing zone. Although the f the effluent has been much less than this, effluent) what the toxicity will be after streams have been removed from the 11 unknown. Therefore, tightening of the ixing zone standard is justified but not to tly demonstrated toxicity.
ABILITY TO ACHIEVE PROPOSED LIMITS:
Monitoring data for the last several months was reviewed and compared to the proposed permit limits. With the exception of fluoride, it appears that compliance would be achieved with all parameters for which data is available. Data is not available for molybdenum, radium, chromium, copper, lead, nickel, zinc, and titanium.
Those processes which must meet fluoride and molybdenum limits are in the metals forming area. These waste streams must be collected and treated in a separate treatment system. A time schedule for constructing the treatment system must be developed. Since the time for achieving the BAT limits has already passed, it will be necessary to put the time schedule, along with an interim set of limits in a stipulated consent order. The current time schedule provided by TWCA is to submit plans and specifications by the end of March with construction to take place the summer of 1988.
TOTAL DISSOLVED SOLIDS:
In the process of neutralizing acid and caustic waste streams and precipitating metals and other pollutants from other waste streams, dissolved solids are generated. Since there is not much that can be done to economically remove dissolved solids without affecting waste^treatment efficiency, a dissolved solids limit is not being proposed at this time. However, dissolved solids monitoring will be required. Dissolved solids concentrations found in the mixing zone do affect the usability of the water for irrigation. One farmer who had leased land from Willamette Industries tried- irrigating from Murder Creek and burned some of his corn. In combination with the hot weather, the high concentrations of dissolved solids (salt) from TWCA contributed to the burning of this crop.
WATER QUALITY EVALUATION:
The discharge from TWCA does adversely impact the quality of waters within the mixing zone. However, if they were not discharging to Truax Creek, it would be dry most of the summer months. The mixing zone includes the Truax Creek/Murder Creek drainage to its confluence with Willamette River plus a radius of 100 feet into the Willamette River. The discharge is not expected to violate water quality standards outside of the mixing zone. In order to confirm this, an evaluation of the Willamette River in the vicinity of the mixing zone will be scheduled for 1988.
COMPLIANCE SCHEDULES:
Several compliance schedules should be included in the permit, as follows: (1) Within eighteen months of permit issuance, the permittee should be required to develop a Best Management Practices
(BMP) plan for site runoff. The BMP plan should be implemented within 2 years of permit issuance.
(2) The permittee should be required to develop and initiate a chronic bioassay procedure by October 1, 1988. Chronic bioassays are to start by March 1, 1989 at a frequency of every 6 months.
(3) During the summer of 1988 the permittee should be required to conduct a special study on the authorized mixing zone in order to assess any loss in beneficial use.
The compliance schedule to be placed in a stipulated consent order for treating the fluoride and molybdenum discharges from the metals forming area is as follows:
Submit plans and specifications by April 1, 1988 Start construction by July 1, 1988 Complete construction by November 1, 1988 Achieve operational level by January 1, 1989
The interim limits to be included in the stipulated order are:
Parameter Monthly ave.(lbs/day) Daily Maxflbs/day)
Fluoride 200 300 Molybdenum 2 ' 18
RECOMMENDATION:
The permit should be issued as drafted. If the studies required of the permittee within the mixing zone and the studies conducted by the Department outside of the mixing zone during 1988 indicate that additional controls are necessary, the permit will be modified to include those controls.
TWCA:CKA
Chapter 5
Waste management programs at TWCA include a wide range of
activities because of the many processes involved in produc­
tion of nonferrous metals and products. T&esJe activities
include process wastewater treatment, SSJCM %aste manage­
ment, hazardous waste management, PQB^quipme'njt'^management,
radioactivermaterial control, wasilg 1*ii,jn.m;lzation through
beneficial use, and air qualife^contfQi^Drograras.
<P JOCE-I IlyAS^EWATER
of industrial w'lifir'ewai۩fs generated from the manufacturing
and forming of nonr'errous metals of zirconium,- hafnium,
titanium, niobium, and refractory metals. Domestic waste­
water is collected separately and discharged into the sani­
tary sewage collection system for appropriate treatment by
the City of Albany.
5-1 CVR153/040
(' CURREf JITUATION SUMMARY Reviso- n 1 January 15, 19 8 8
system. Metals removal is accomplished by neutralization
with lime, magnesium hydroxide, or sulfuric acid and carbon
dioxide to pH 6 to 8 to form metal hydroxides and .sulfates.
Fluorides are removed by the formation of calcium fluoride.
These compounds are removed in a clarifier by settling.
Solids generated from the operation of the clarifier,
referred to as "sludge," are placed in storage ponds for
additional settling and dewatering (sey6»^\1jLsoussion that
follows on wastewater treatment syst ra/s01151%,,'"%
An emergency neutralization s Sitgm il^ih^place so that the
treated wastewater's pH can b% \ep fc ,w"i%hin acceptable limits,
should the central wasJ^WAt^r iSrefitment system malfunction,
before its discharge\t&S<,Truax, "&r§'ek. Sodium hydroxide, sul-
neutralization €ystem\ % '*'
Other systems used'Vc TWCA located on the upstream side of
the central wastewater treatment system include:
o Dechlorination to remove residual chlorine from
the blowdown of air pollution control devices
employed for the removal of chlorine and chloride
from gaseous emissions
o Spill collection and treatment to assist in meet­
ing limits for MIBK, ammonia, and thiocyanate from
the separations process
of thiocyanate within the separations process
o Ammonia recovery
o MIBK steam stripping "tfcii?:, cbn&rbl and recovery of
MIBK within th§2'Separ|af;-;4'ons process
o Barium-sWi'Cat:^ laoprecipitation for control of
radium \ \ ''¥'
filtration for solids dewatering
ammonium sulfate for use as fertilizer or recycl­
ing in the zirconium/hafnium separations process
Figure 5-1 is a block diagram of the treatment systems and
process wastewater sources at TWCA.
5-3 CVR153/040
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