Wet Cleaning

The Greener Cleaner Wastewater Report

August 1996

A cooperative effort between the Greener Cleaner, The Center for Neighborhood Technology, the Metropolitan Water Reclamation District of Greater Chicago, and the Illinois Hazardous Waste Research and Information Center

INTRODUCTION

At the request of the Center for Neighborhood Technology (CNT), the Illinois Hazardous Waste Research and Information Center (HWRIC) and the Metropolitan Water Reclamation District of Greater Chicago (MWRD) conducted a three day sampling study in February 1996 of The Greener Cleaner to study the effluent and the impact wet cleaning may have on the environment.

BACKGROUND

The Greener Cleaner is a professional garment cleaning shop in Chicago designed by its owner and CNT to test and demonstrate wet cleaning with funds for research provided by the U.S. Environmental Protection Agency. Wet cleaning includes a range of technologies and techniques that use water to clean clothes that are typically dry cleaned. With the growing concern regarding the health and environmental impact of the common dry cleaning solvent, perchloroethylene, CNT began research into water-based alternatives. The Greener Cleaner is intended to mirror an average commercial dry cleaning operation in volume, rates, and types of fabrics and garments cleaned.

Except for the wet cleaning machine and accompanying dryer, the equipment used in The Greener Cleaner is not atypical of the equipment in a dry cleaning establishment. The wet cleaning machine is a Wascomat /Aqua Clean ACS50G 50 lb. washer with a 30 lb. gas heated dryer. Auxiliary equipment includes a domestic Whirlpool top loading washing machine, a steam pressing system, a gas-fired boiler, a compressor, a water softener and a sink basin.

A special detergent and sizing formulated for wet cleaning applications is purchased from the equipment distributor to use in the wet cleaning machine. Both products are automatically dispensed to the machine at quantities set by the individual cycle programs. The detergent, Aquasafe Detergent by Aqua Clean Systems, is a combination of active detergents, glycol ether, proprietary anti-shrinking agents, and alcohol dissolved in water. The sizing is made up of the same chemicals, without the alcohol. Occasionally, starch, citrisolv and other spot cleaners are used, some of which contain hazardous chemicals. Many of the spot cleaners are hydrocarbon based. Regular residential type detergents are used in the domestic washing machine.

WATER AND WASTEWATER

All of the equipment uses water, with the largest users being the wet cleaning machine and the domestic washer. Water use was recorded from the incoming water meter during two days of the study, but since several pieces of equipment operate at any given time, water use on individual machines was not readily measured for each load.

The wet cleaning machine has a programmable controller which meters water and chemicals, as well as controlling water temperature, time, humidity and mechanical agitation. Water consumption varies by program and whether a full or half load is selected. Programs are selected based on fabric and garment type. There were over a dozen programs provided with the machine and more can be added by the user. When scheduling permitted, water meter readings were taken when the domestic washer and pressing system were not operating in an attempt to get an isolated water usage. Comparing all data, water consumption for the wet cleaning ranged from 42 gallons to 52 gallons for a full load. This did not coincide with information provided in the equipment manufacturer's literature but the machine has been reprogrammed by The Greener Cleaner staff.

Wastewater from an empty load in the domestic washer was captured in the sink basin and the amount measured. Since the load was empty, the quantity of wastewater is equal to the quantity of raw water used; water was not lost in dragout with the clothes and evaporation of the cold water was negligible. Water consumption on a small and medium load was 23 gallons and 29 gallons respectively which confirms the water meter readings taken at the same time (The small setting is used most of the time).

In addition to fresh water for make-up for the generation of steam from the boiler, the boiler is emptied every night and refilled each morning with 15-23 gallons. The water softener resins are regenerated every night, which consumes 220-225 gallons of fresh water.

Total facility water use does not equal wastewater discharge due to evaporative losses from drying and steam in pressing. However, equipment was not available to measure the wastewater discharge. Subtracting known water use for the washing machines, boiler fill, and water softener from the total water meter readings gives an estimate of evaporative steam losses.

The quantity of water used per load washed, less the amount that is still contained in the clothes when transferring to the dryer, is the amount of wastewater that is discharged to the sewer from the washers. The wastewater from the washers contains detergent, sizing, traces of spot cleaners and contaminants that were on the clothes (dirt, grease, food, etc.). Some foaming is visible in the manhole so the discharge of detergent is evident. Wastewater containing a buildup of suspended solids and dissolved solids is generated when the water remaining in the boiler is emptied every night (maximum 23 gallons). Wastewater is also generated from recharging the water softener (200-220 gallons). Recharging the water softener will generate a backwash containing suspended solids and the spent regenerant will contain high levels of the ions that have been removed (principally, calcium and magnesium) as well as the regenerant (salt). A very small quantity of blowdown from the air compressor is periodically discharged (less than 5 gallons) but this should be free of pollutants. The amount of spot cleaners that enters the washer is minimized by the use of a vacuum pump system on the spotting board which draws the liquid out of the fabric and collects it in a canister. Not enough of the liquid has been collected to require disposal because most of it evaporates from the canister (capacity approximately one gallon). The usage of these cleaners is very low. Most of the spot cleaners being used are the original bottle purchased, which is typically one to two quarts, except for Picrin, which is used more frequently.

TRACKING RESULTS

On February 27^th, twenty-three loads were cleaned; 10 full and 4 half loads in the wet cleaner and 9 loads in the domestic washer. Only three different programs were used on this day, and most of the loads were done using a wool program (This program is gentle and good for loads made up of different fabrics and since it was winter, there were many garments containing wool.) Using an average of 48 gallons and 32 gallons for the full and half wet clean loads respectively and 23 gallons (typical) for the domestic washer, water consumption for washing is estimated at 815 gallons. Total water meter readings for the day were 1100 gallons. Accounting for the 200 gallons for the water softener regeneration and 23 gallons to refill the boiler, evaporative losses accounted for approximately 62 gallons, or 5.6% of the total water consumption. The number of garments cleaned with both washers on this day was 187 pieces, weighing 189 pounds total. This equates to 4.63 gallons of water per pound of clothes.

On February 28^th, twenty loads were cleaned; 9 full loads and 1 half load in the wet cleaner and 10 loads in the domestic washer. Only three different programs were used on this day, again mostly the wool program. Using the same averages as above, water consumption for washing is estimated at 694 gallons with a total daily consumption of 1055 gallons per meter readings. Therefore, evaporative losses account for approximately 138 gallons, or 13 %. On this day, 126 pieces were cleaned, weighing 135 pounds thus averaging 5.66 gallons of water per pound of clothes.

There were several loads during the study in which only one or two pieces were cleaned due to scheduling or garment color or weight. The maximum size load cleaned was 20 pounds with an average of 7.5 pounds per load. The size of the load depends on the type and color of garments and the volume ready to be cleaned. The Greener Cleaner is capable of increasing throughput on the wet cleaner if customer traffic increases. The wet cleaner capacity is 50 pounds per load, and at this capacity, the water consumption rate would be approximately one gallon per pound of clothes. It is very unusual for a machine to run at its design capacity. Therefore a more realistic figure may be 2-5 gallons per piece.

If the wet cleaning machine were run at maximum throughput for 24 hours with a typical cycle time of twenty minutes and maximum water use of 52 gallons per load, 3744 gallons of water would be used for the 72 loads. If the domestic washer were run at maximum throughput with a typical cycle time of 40 minutes and maximum water use of 29 gallons per load, an additional 1044 gallons of water would be used for the 36 loads. The total water use for the facility would be close to 5700 gallons per day.

EFFLUENT TESTING

The seriousness of the effect a facilities wastewater will have on the receiving body depends on the characteristics of the wastestream, the size and design of the receiving system and the standards for sludge and wastewater disposal or reuse. The Greener Cleaner discharges to the MWRD treatment system which has a flow rate of 800 million gallons per day. The estimated maximum volume of water that could be generated at The Greener Cleaner is 5700 gallons per day which is equivalent to 7 part per million in the District flow. Therefore, it is very unlikely that the discharge from The Greener Cleaner or other wet cleaners will have any significant impact on the treatment system. However, wet cleaning operations may not always be located on a large sewer system; they may discharge directly to a waterway or a septic system. Prior to sampling The Greener Cleaner, the project and objectives were presented to the Illinois Environmental Protection Agency (IEPA) by CNT and HWRIC to obtain input with regard to discharges to a private sewage disposal systems (septic) or waterway. A response was received from the IEPA Bureau of Water and the Illinois Department of Public Health regarding the parameters and pollutants of concern to the respective discharge points. These pollutants and other parameters were included in the study. MWRD also provided a response for discharges to a sewer system.

A Sigma 1350 automatic sampler was installed on the facility effluent of the Greener Cleaner by a MWRD pollution control officer on the morning of February 26, 1996 and removed on February 29, 1996, providing three individual days of composite sampling.

The sampler was installed at a manhole which receives all wastewater from the facility except the restroom. This includes discharges from the wet cleaning machine, domestic washer, pressing/spotting equipment blowdown, compressor blowdown, wash basin wastewater and water softener regeneration waste. The sampler was programmed to take equal volume aliquots every ten minutes during the 24 hour period. The samples were kept on ice in the automatic sampler to maintain sample quality. In addition, four grab samples, were taken in zero head space glass vials (to prevent evaporation of volatiles) every fifteen minutes for an hour each day and composited to analyze organics. All samples were delivered to the MWRD laboratory and analyzed by qualified personnel. On February 27^th and 28^th, water use, number of loads, pieces and pounds of clothing and other activities were tracked. Washing and pressing generally took place between 5:30 AM and 2:30 PM so most of the discharge occurred during this time except for the water softener regeneration which was programmed for 2:00 AM. Nothing unusual occurred during the sampling and the soaps and spotting chemicals used during the sampling were the same as have been used since start-up of The Greener Cleaner. Compressor blowdown and pressing/spotting equipment blowdown was not discharged to the sewer during the study.

The samples were analyzed for twelve different metals, biological oxygen demand (BOD), suspended solids (SS), fats/oils/grease (FOG), nitrogen, phosphorous, and 122 total toxic organics (TTO's). The results for the three days are given in Table 2 and Table 3. Water meter readings were taken in between days and pH was checked each day by the field inspector and found to be neutral.

Biochemical Oxygen Demand, Suspended Solids and Fats, Oils, and Grease

Biochemical Oxygen Demand (BOD) is the rate at which organisms use the oxygen in water while stabilizing decomposable organic matter under aerobic conditions. It is used as a measure of the organic strength of wastes in water and is actually a measure of the environmental impact of chemical pollution. When organic matter (pollutants in wastewater) is plentiful, microorganisms may grow so rapidly that they deplete the dissolved oxygen to the extent that levels can be harmfully low for fish and aquatic life. Generally, municipal wastewater treatment plants are capable of reducing or removing moderate to high levels of BOD but in some cases, pretreatment is necessary. BOD, to a certain extent, can be beneficial in a septic system. BOD varies widely from industry to industry. It is not uncommon to find metal finishing wastewaters with BOD concentrations less than 200 mg/L, food processing in the tens of thousands, and wool production contributing 400 pounds of BOD per 1,000 pounds of cloth produced¹. MWRD uses a Standard Domestic Waste Strength Concentration for BOD of 119 mg/L which is typical for a residential setting. BOD concentrations for The Greener Cleaner were between 200-400 mg/L, much of which can be attributed to the detergents. This is consistent with industrial laundries in the Chicago area and acceptable by MWRD sewer systems. However, BOD is too high to discharge directly to waterways under the jurisdiction of MWRD (e.g. Calumet River, Chicago River, etc.) and in many cases, will not be acceptable for discharging directly to any waterway such as a stream, pond, or river which will have allowable limits much lower than this depending on the water body. The detected levels will not pose any problem to the operation of a septic system.

Suspended Solids (SS) and Fats, Oils and Grease (FOG) concentrations from The Greener Cleaner were fairly low. These pollutants can be a visible problem and contribute to oxygen consuming wastes in a water body. The Greener Cleaner is well within the MWRD defined Standard Domestic Waste Strength Concentration of 168 mg/L for suspended solids and the acceptable limit of 250 mg/L for FOG and also would not pose a problem to the operation of a septic system. However, there are many treatment systems that have a lower limit for FOG, such as 100 mg/L and some even lower. Direct discharges to waterways also have lower limits for SS and FOG. For example, discharges to the Chicago River must contain less than 25 mg/L SS and any direct discharge to waterways under jurisdiction of, MWRD must have less than 15 mg/L FOG. Therefore, these pollutants may preclude direct discharge to a waterway from a cleaner without pretreatment.

In many cases, as with MWRD, there is a surcharge or fee for the discharges of BOD and SS. Using the MWRD 1996 User Charge rates of $183.45 per thousand pounds of BOD and $162.71 per thousand pounds of SS, The Greener Cleaner would be assessed approximately $150 per year for BOD and $15 per year for SS. [Note: This is for illustration purposes only. The Greener Cleaner pays for sewer use through ad valorem taxes and is not required to pay any surcharge fees to MWRD per the User Charge Ordinance, which classifies the cleaner as a Small Nonresidential Commercial-Industrial User. Only Large Commercial-Industrial Users (discharges greater than 25,000 gallons per day or 25 pounds per day BOD or 35 pounds per day suspended solids) and/or Significant Industrial Users are required to pay a surcharge for BOD, SS and flow in excess of the ad valorem taxes.]

Nitrogen, Ammonia Nitrogen and Phosphorous

Phosphorous and nitrogen are nutrients that promote the growth of algae and larger vegetation. Too much algae and vegetation can become an interference. And as this algae breaks down, dissolved oxygen is consumed. Several years ago, phosphates were a serious problem for water bodies and this led to regional bans on phosphate containing detergents, which were a significant source. Depending on the receiving stream, phosphorous and nitrogen can be a "wanted" addition or an "unwanted" pollutant. Ammonia nitrogen is a toxic chemical and can be harmful to fish. It also could cause oxygen depletion and is difficult to treat biologically. All three of these pollutants from The Greener Cleaner are lower than the typical domestic sewage raw influent to the MWRD treatment systems and should not pose a problem, nor should it cause difficulties for a septic system. Direct discharges to waterways may have lower limits.

Metals

Metals in wastewater cannot be destroyed, only removed or their chemical form changed (and therefore environmental availability). If not removed prior to entering a municipal treatment system the metals are either transferred to the sludge and accumulate or they pass through the treatment system as effluent. These metals can be toxic to aquatic life, especially if they are bioaccumulative, and if metal concentrations are too high in the sludge, the sludge could be considered a hazardous waste. Municipal treatment systems have limits on the amount of metals that can be discharged from an industry. Sometimes these limits are general and apply to all discharges and some are more stringent and apply to a certain industry type or process. These limits are also dependent on the treatment systems ability to remove the metals.

The metals in The Greener Cleaner effluent were well within limits for the MWRD sewer system and direct discharges to waters under jurisdiction of MWRD. The total of the metals for the sample collected on 2/26/96 at 0.37 mg/L was even below all of the limits for individual metals except mercury for discharges to the sewer system. This is as suspected since residential garments should not carry any metals. It is unknown what the background levels of these metals is in the raw incoming water but some of the detectable metals may be attributed to this.

Total Toxic Organics

One-hundred seventeen volatile organics, semi-volatile organics, pesticides and PCB's that are listed as water priority pollutants and several other chemicals were tested each day during the study. Most of these pollutants were found in less than quantitation limits. Table 3 gives a summary of the concentration of the pollutants that were detected.

Phthalates

The concentrations of phthalates in the waste stream was fairly consistent during the three days of testing. This consistency along with the knowledge that phthalates are common ingredients in detergents leads to the conclusion that these detected phthalates are in the detergent and/or sizing used at the facility (there is no mention of such on the Material Safety Data Sheets). Other known uses and water quality data for these chemicals are as follows:

• Diethyl phthalate: Uses include plastics manufacturing and processing, explosive propellant ingredient, mosquito repellent, perfumery, FDA packaging applications and as a wetting agent. The toxicity threshold for cell multiplication inhibition for green algae is 10 mg/L.
• Di-n-butyl phthalate: Uses include plastics manufacturing and processing, explosives propellant ingredient, cosmetics, safety glass, insecticide, inks, paper coatings, adhesives and textile lubricating agent. Human caused sources include detergents, lipsticks, evaporation from perfumes, inks, and insecticides, and application of paints, coatings and adhesives. It has been found in domestic sewer effluent at 0.2 mg/L.
• Butyl benzyl phthalate: Used for plasticising synthetic resins. The range in natural waters is non-detectable to 0.0041 mg/L. It can be found in domestic activated sludge in the inlet at 0.008 mg/L and 0.0013 mg/L at the outlet. It has no effect on fathead minnows at concentrations of 1-2.2 mg/L.

Some of these phthalates are also detected in MWRD treatment plants. Data for three of the smaller plants, Northside, Hanover Park and Lemont were obtained for purposes of comparing concentrations to The Greener Cleaner. The three plants ranged from 0.0036 to 0.0094 mg/L of diethyl phthalate in the raw sewage. Two of the plants showed levels of 0.0027 and 0.0030 mg/L of di-n-butyl phthalate and one plant showed 0.0158 mg/L butyl benzyl phthalate also in the raw sewage. Bis(2-ethylhexyl) phthalate was found in sludge at all three plants at levels from 0.891-1.554 mg/L. Phthalates at the levels found in the effluent should not pose any problems when discharged to a sanitary sewer or septic system. Based on the above information, it does not appear that these phthalates would pose any threat when discharged directly to a water body at the detected levels.

Acids

Dodecanoic acid, hexadecanoic and octadecanoic acids are more commonly known by the names lauric acid, palmitic acid and stearic acid respectively. These fatty acids were consistently detected in the 1-4.2 part per million range in most of the samples. Uses and water quality data for these acids are as follows:

• Lauric acid: Lauric acid is used for alkyd resins, cosmetics, insecticides, food additives, wetting agents, soaps, and detergents. In testing it had no effect on rats fed a diet of 35% lauric acid for two years.
• Palmitic acid: Palmitic acid is found in sewage effluents at 0.1 mg/L. 11 mg/L to goldfish is considered a lethal dose.
• Stearic Acid: Stearic acid is used for lubricants, pharmaceuticals, cosmetics, shoe and metal polish, a dispersing agent and softener in rubber compounds, food packaging, and soaps. It is found in domestic sewer effluent at 0.05 mg/L and a lethal dose to goldfish is 14 mg/L.

Based on the above information, it does not appear that these acids would pose any threat when discharged to the sewer, septic system or directly to a water body at the detected levels. They would be greatly diluted in the wastewater treatment plant or stream which would provide a very large safety margin.

Acetone

Acetone was found in The Greener Cleaner effluent at 0.147 ppm during one day of the study. Acetone² is a common industrial solvent for cleaning, painting and other coatings. It is also used in the pharmaceutical industry and as a solvent for cellulose acetate. It is used in the manufacturer of smokeless powder and is found in cigarette smoke at 1100 ppm. It can cause adverse effects in humans and is found to cause signs of illness in humans at 800 ppm in air. It is not known whether the acetone in The Greener Cleaner was from a spot cleaner or the residuals of smoke in customers items. Lace curtains smelling heavily of cigarette smoke were soaked in several gallons of water (due to the smell) for a few hours prior to being washed in the domestic washer on this day. Acetone is easily biodegraded in wastewater treatment plants and the level found should pose no environmental threat.

2-(2-Butoxyethoxy)ethanol

This is also known as diethylene glycol monobutyl ether or Dowanol DB and is a common industrial solvent used in paints, varnishes and coatings as well as cleaners, detergents and soaps. It is in the glycol ether family which is a Clean Air Act Hazardous Air Pollutant and a SARA 313 Form R reportable class of chemicals. Glycol ethers are listed in the constituents on the Material Safety Data Sheet for the wet cleaning detergent, the sizing and a Citrisolv product used for spot cleaning. That explains the consistent pattern of 5.5-6.9 mg/L in the effluent. Testing has shown a toxic threshold of 53 mg/L for cell multiplication inhibition in algae and no effect on rats for repeated oral doses of 0.051 g/kg. Therefore the levels found in The Greener Cleaner effluent should not be an environmental concern.

Trichloroethylene

Trichloroethylene is used for metal degreasing, as a solvent for fats, greases, and waxes from cotton, wool, etc., for removing caffeine from coffee, solvent for dyeing, and a refrigerant. Trichloroethylene is a Clean Air Act Hazardous Air Pollutant and a reportable chemical under SARA 313 toxic chemical reporting. Toxic threshold testing shows cell multiplication inhibition in algae at 63 mg/L and it is shown to cause illness in humans at 800 ppm inhalation. A spot cleaner that is used on a regular basis at dry cleaners and The Greener Cleaner called Picrin is 100% trichloroethylene. It is assumed that this is the source of the 0.287 ppm trichloroethylene found in the effluent on one day when one very dirty coat was cleaned. Trichloroethylene is also found in the MWRD systems at 0.0080 mg/L in the raw sewage, 0.0047 mg/L in sludge and 0.0023 mg/L in the effluent (discreet data point typical of system). Trichloroethylene would be a concern for discharges to a septic system. The USEPA drinking water standard is 5 parts per billion. Since trichloroethylene is very mobile in groundwater, there would be a potential for groundwater contamination and thereby contamination of nearby drinking water wells. It would be advisable for alternative spot cleaners to be utilized when possible to eliminate this pollutant source.

POLLUTION PREVENTION OPPORTUNITIES

Depending on the geographical location of a wet cleaning establishment, water could be considered a costly commodity. The Wascomat wet cleaning machine used at The Greener Cleaner is capable of recirculating some of the water for different cycles. This option has not been used to avoid any risk of cross contamination, since one of the primary focuses of The Greener Cleaner research has been cleaning quality. In addition, the cost of water and sewer use at The Greener Cleaner is a minimal expense and wastes from this particular cleaning operation pose very little environmental impact. The Wascomat has a holding tank at the bottom of the machine but there are no filtration or purification capabilities built into the unit. If it was desirable to reuse the water for different cycles but there is a fear of using "dirty" water, it is possible to clean the water using filtration before recirculating it. Micron bag filters could easily be used to remove large particles such as lint, buttons, dirt, food, blood, free oil, etc. Bag filters may not be able to remove color, tobacco, bacteria, emulsified oil and other smaller molecules. Most of these smaller contaminants could be removed using ultrafiltration, a process using a membrane material to remove molecules between the range of 0.1 - 0.01 micrometers.

A bench test ultrafiltration test was performed by HWRIC on a small sample of effluent from The Greener Cleaner to see if membranes were compatible with the wastewater and to get a visual look of the filtered water. Visually, there was a noticeable difference between the pre- and post- filtration samples for solids. Soap suds are formed in the postfiltration sample when shaken showing that the soaps are still active even after filtration. Therefore, money could be saved in both water costs and chemical usage. The cost of this technology is based on flow rate and can be relatively expensive. More extensive testing and analytical studies would have to be performed before a conclusion could be reached about the technical feasibility and cost effectiveness, but based on knowledge of the process and the appearance of the bench test sample, it appears to be a viable option. Filtration would allow the reuse of some of the chemicals in the detergents which should reduce the amount of detergent chemicals discharged to the sewer.

Additional water conservation may be possible by determining the optimum amount of water needed for the different cycles without sacrificing cleaning quality. As mentioned previously, the pounds of clothes cleaned per gallon of water can also be increased up to the capacity of the machine.

To reduce or eliminate toxic chemicals within the wet cleaning process, non-hazardous spot cleaners need to be identified. In this case, a substitute for Picrin should be sought. Some of the other spot cleaners that are available for removing specific substances, such as rust, also contain quite harmful chemicals. Spot cleaners used in the dry cleaning industry are removed from the shop via air emissions or off-site disposal in the perchloroethylene. A wet cleaning operation will also have loss through evaporation but chemicals left on the clothing will be removed with water in the wet cleaning machine, which will end up as a discharge. A shop promoting to be "environmentally friendly" should be aware of the contents of the spot chemicals used and seek non-toxic or less toxic chemicals whenever possible.

CONCLUSION

Environmentally speaking, wet cleaning has many advantages over dry cleaning including minimal emissions, less toxic raw materials and no hazardous waste. With dry cleaning, the concerns are primarily with air emissions, worker safety and hazardous waste management. With wet cleaning, those problems, including worker safety, are greatly decreased but wastewater concerns are somewhat increased.

Waste generation consists of wastewater containing detergent, sizing, lint, oil and grease and other traces of chemicals that may have been present on the garments cleaned. This wastewater should be acceptable to most municipal wastewater treatment systems, most often without the need for any on-site pretreatment by the cleaning establishment. Metal concentrations in the wastewater were not found to be significant. Concentrations of toxic organic chemicals in the wastewater were generally below regulatory concern. There may be environmental concerns, including BOD and suspended solids levels, with discharges to small municipal systems and direct discharges to streams and other waterways. A likely area for concern among municipalities, septic systems, and direct waterway discharges, as seen from the testing conducted at The Greener Cleaner, is the presence of hazardous spot and stain removers. Spot cleaning and pre-cleaning with spot removers for stains and other hard to clean spots prior to washing is essential in wet cleaning. Many of the spot cleaners on the market are hydrocarbon based solvents so this is a consideration in the effluent. Efforts should be made to locate spot cleaners that are not harmful to the environment.

It was anticipated that trace amounts of perchloroethylene (tetrachloroethene) would be detected in the wastewater as residuals from clothing that had previously been dry cleaned. However, levels were below quantitation limits of 10 parts per billion.

Water use for the Greener Cleaner is just over one thousand gallons per day for one wet cleaning machine, one domestic washer and ancillary equipment. This should not be considered an exorbitant amount of water for a business of this type. Water use per pound of clothing varies based on garment types and availability. Large shops will have a lower water usage per pound of clothing and therefore be more efficient because of the available volume of garments with like characteristics, making it easier to maximize loads.

Depending on the geographical location of a facility, water conservation through recycling may be economically attractive and options are available to do so. In process filtration, technologies can not only reduce the amount of water required but indications are that they can also recover unused chemicals including the detergents. More study is needed to evaluate the technical effectiveness and economics of using filtration to minimize waste generation and recycle water/chemicals.

BIBLIOGRAPHY

California State University Department of Civil Engineering, Industrial Waste Treatment. Second Edition, Volume 1, California State University, Sacramento Foundation, 1994, p. 12-19. Karel Verschueren, Handbook of Environmental Data on Organic Chemicals, Van Nostrand Reinhold Company, New York, NY, 1983, p. 147,312, 468, 524, 530, 792, 941, 1053, 113 1. Report prepared by: Ms. Chris Hayes, HWRIC, August 8, 1996 Reviewed by: Dr. Gary Miller. HWRIC Mr. Bill Eyring, CNT Acknowledgments: Ms. Hayes would like to thank The Greener Cleaner owner and staff, especially Ms. Ann Hargrove, for their cooperation and patience during this study. Thanks are also extended to the following people for their assistance in conducting the study and analyzing the results: Mr. Bill Eyring, CNT, Mr. Richard Lanyon, Mr. Al Giedraitis, Mr. George Richardson and their staff, MWRD, Mr. Jim Janssen and Mr. Tom McSwiggin, Illinois EPA, Mr. Clinton Mudgett and Mr. David Antonacci, Illinois Department of Public Health, and Dr. Gary Miller, HWRIC.