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WaterWater EfficiencyEfficiency Management Options

Reuse and Reclamation

Maximizing utility of in-process water is ac- complished by using it more than one time to do work. characteristics will determine if multi-functional use of in-pro- cess water is acceptable for achieving neces- sary product quality control/assurance. For- tunately, many technologies can provide cost-effective opportunities to re- duce demand and the resultant savings can be used to justify capital costs. De- pending on water quality requirements for the stage of use, water may simply be recirculated or require only basic treatment such as solid settling, oil skimming and/or using cartridge, bag, disk, indexing fabric or sand for Commercial, Industrial filtration. (See Figure 4-13.)

and Institutional Facilities Water quality standards need to be carefully established for each point of multiple-use. For high water quality demands, technologically advanced water treatment techniques exist such as , , hyperfiltration (), carbon fil- tration and .

N.C. Division of Prevention and Environmental Assistance 1639 Mail Service Center Raleigh, NC 27699-1639 (919) 715-6500 (800) 763-0136 Fact Sheet May 2009

CAUTION: RECLAIMED WATER DO NOT DRINK

Additional uses of in-process water maintained for all closed-loop systems. A re- can also allow the user to salvage a valuable siduals management plan shall be maintained product that presently is being discharged as for all systems that generate residuals. a constituent, such as cleaning chemicals in washing solutions or valuable N.C. Division of Water Quality issued non- metals in rinsing solutions. This may also re- discharge permitting is required for closed– duce surcharges. loop recycle systems that are not under roof (i.e., exposed to precipitation inputs) and/or Consider staged cleaning techniques where utilizing an earthen basin for storage. Special the first- and second-pass cleaning water is conditions apply as defined in the Subchap- saved for further use or reclamation of chemi- ter 2T rules. cals. Industrial in-process effluents can be directly In-Process Water reused without a DWQ non-discharge permit Rules in these specific situations: Areas in North Carolina are approaching lim- „ Industrial in-process water reused within its on seasonal availability of high-quality raw the facility that originated the . source water. One way to reduce withdrawal „ make-up water. of source water is to reduce demand by imple- „ Fire-fighting or extinguishing water. menting reuse of industrial in-process - Reuse of industrial in-process effluents are water to increase water efficiency. North allowed as specified in the Subchapter 2T Carolina’s Environmental Management Com- rules. Before constructing a water reuse sys- mission rules support the reuse of industrial tem, it is important to verify if a permit will in-process wastewater to increase water effi- be needed. Modifications to an existing wa- ciency. ter reuse system may require permitting and/ or modification to an existing permit (e.g., pre- Title 15A NCAC Subchapter 2T, Section treatment industrial user permit). .1000 applies to closed-loop recycle systems where non-domestic wastewater is repeatedly All types of industrial/commercial water re- recycled back through the process in which use require the facility to assure protection of the water was generated. This section permits employee health and safety, and to notify em- by regulation (i.e., no permit needed) the re- ployees that non-potable water is being reused. turn of wastewater contained and under roof All valves, piping and storage facilities of in- within an industrial or commercial process. process reuse water must be tagged or labeled Spill control plans are required for these sys- to inform employees that the water is not in- tems that do not have secondary containment. tended for drinking. An operations and maintenance plan shall be

2 May 2009 Water Efficiency Fact Sheet

Reclaimed Water tems. Reclaimed water effluent standards are very stringent in order to provide for protec- Systems Rules tion from . Reclaimed water systems are classified in the rules as conjunctive only Reclaimed water must meet two criteria. First, if the wastewater treatment plant that pro- whether treated or untreated, it must meet duces the effluent has the capability to dis- specific qualitative standards. Second, it must pose of this water by another method (e.g., also be reused in a beneficial manner for the NPDES permit). Facilities producing re- purpose of conservation of the state’s water claimed water are permitted by the N.C. Di- . The most common reclaimed wa- vision of Water Quality Protection ter is effluent from a tertiary wastewater treat- Section, Application Unit. ment process. Reclaimed water utilization serves to offset the use of potable water, sur- In some localities, it is now possible for cus- face water and/or . The water tomers to receive reclaimed water that is dis- resources benefit derived from the use of re- tributed directly from a publicly owned waste- claimed water is to offset withdrawal of raw water treatment plant. Reclaimed water dis- water for supply from another location in the tribution piping is distinguishable from po- hydrological system. table lines by being colored purple or wrapped and continuously embossed or integrally The rules in Title 15A NCAC Subchapter 2T, stamped or marked "CAUTION: RE- Section .0900 apply to reclaimed water sys- CLAIMED WATER - DO NOT DRINK." No cross-connections are allowed to occur be- tween the reclaimed water system and potable CASE STUDY water systems. Where potable water is used to supplement the equipment using reclaimed In-Plant Water Reuse water, an air gap must separate the potable and reclaimed water. The supplemental sys- Previously, the open-loop cooling sys- tem is then subject to approval by the potable tem on the emergency generator at the water supplier. Michelin Aircraft Tire Corporation in Norwood pumped 150 gallons of wa- Once reclaimed water is distributed to cus- ter per minute into the storm water tomers it is not allowed to be directly dis- outflow drains. The facility replaced the charged to the surface of the state by open-loop generator cooling system the customer. If the reclaimed water is used with a closed-loop generator cooling to supply a landscape system, run- system that recycles water from an off into catchments and convey- onsite cooling pond. The facility also re- ances is not allowed. placed faucets and After reclaimed water is used, it can be dis- with more efficient reduced flow, mo- posed of only in a manner in which it is ei- tion sensor models. As a result of the ther assimilated into a product (e.g., closed-loop cooling system and bath- batch), transpired (e.g., plant uptake), evapo- room fixture replacements, the facility rated (e.g., cooling tower) or discharged into reduced water consumption by 4.8 a wastewater treatment collection system. million gallons per year.

3 Water Efficiency Fact Sheet May 2009

Examples of acceptable uses for reclaimed chain ; make-up for swimming pools, water are: spas and hot tubs; and raw water supply. „ and landscape irrigation Bulk distribution of reclaimed water is made „ control available to customers by permitted wastewa- „ compaction ter treatment facilities. Contact the local pub- „ Non-potable industrial processes such as lic works department to see if your public util- cooling water concrete production ity service provider has been approved to dis- „ Industrial and commercial flush tribute reclaimed water. and fire prevention systems where there are separate, non-potable plumbing lines Industrial effluents meeting reclaimed water „ Decorative ponds and fountains effluent standards can be permitted by the „ Street cleaning N.C. Division of Water Quality Aquifer Pro- „ Vehicle washing tection Section, Land Application Unit, in „ Cooling tower and boiler make-up order to beneficially use the effluent outside of the industry’s process. The rules also have N.C. Environmental Management Commis- provisions to allow for the distribution of such sion rules specify criteria that apply to certain a reclaimed water effluent to other entities. uses of reclaimed water as an added control measure to protect public health and the en- For additional information about water reuse, vironment. The rules prohibit the use of re- reclaimed water and rule language in the claimed water for irrigation of direct

FIGURE 4-13

4 May 2009 Water Efficiency Fact Sheet

“Waste Not Discharged to Surface Waters” subchapter, see the N.C. Division of Water Quality Aquifer Protection Section, Land Ap- plication Unit’s Web page at: http://h2o.enr.state.nc.us/lau/main.html.

CASE STUDY CASE STUDY

In-Plant Water Reuse In-Plant Process Water Reuse BSH Home Appliances in New Bern Jackson Paper in Sylva manufactures installed a system in its enameling fa- corrugated cardboard medium from cility that filtered rinse water from the 100 percent recycled feedstock. An parts washer and reused the water in on-site wastewater facility allows the first stages of the washer. This 100,000 gallons of wastewater per day project saved the to be reused on-site. Treated mill wa- facility approximately 2,500 gallons of ter is reused for papermaking, boiler water per day of operation. Several scrubber make-up water and additional filters were added to the press showers in the wastewater washer system to keep the water in treatment area. No wastewater is dis- the tanks cleaner for longer use, thus charged from the facility. The inten- reducing the frequency needed to sive water reuse modifications save an dump and clean the tanks. estimated $92,000 per year.

The North Carolina Division of Pollution Prevention and Environmental Assistance provides free, non-regulatory technical assistance and education on methods to eliminate, reduce, or recycle before they become pollutants or require disposal. Telephone DPPEA at (919) 715-6500 or (800) 763-0136 for assistance with issues in this fact sheet or any of your waste reduction concerns.

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