ADDENDUM TO THE FACT SHEET FOR NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES) PERMIT NO. WA June 25, 2010

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1 ADDENDUM TO THE FACT SHEET FOR NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES) PERMIT NO. WA June 25, 2010 I. GENERAL INFORMATION Facility: City of Blaine Wastewater Treatment Plants 9235 Semiahmoo Parkway and 272 Marine Drive Blaine, WA This fact sheet addendum amends the 2007 fact sheet accompanying NPDES Permit No. WA , issued to the Blaine Wastewater Treatment Plant (Blaine) on November 2, The Department of Ecology (Ecology) proposes to modify the permit as requested by the facility and as described below. II. PERMIT MODIFICATIONS Background Ecology proposes to modify the permit to add Blaine s new Lighthouse Point Water Reclamation Facility (LPWRF) to the City of Blaine s current NPDES permit. The LPWRF is located on the east side of Drayton Harbor; the existing wastewater facility which employs Rotating Biological Contactor s (RBC s) is on the west side of Drayton Harbor. The City of Blaine (City) started to upgrade and expand the RBC facility in 1999 when it encountered ancient human remains and stopped construction. The City reached an agreement with the Lummi Nation that, in part, requires it to demolish the present RBC plant once it builds a new wastewater facility. The City is completing the LPWRF project in three phases. The project is currently in Phase II; the City is building a new facility on the east side of Drayton Harbor next to the City s Marine Park. During Phase II, Blaine will run both plants at the same time with the old RBC facility taking flows from West Blaine and the LPWRF receiving flows from East Blaine. When the project reaches Phase III, the City will treat all wastewater at the LPWRF from both East and West Blaine and it will demolish the RBC plant. LPWRF Treatment System Influent wastewater undergoes preliminary screening and grit removal before it flows through fine screens. The operator will transfer removed grit to a dumpster for disposal at a landfill. Wastewater flows from the grit chamber through fine screens and then to aeration basins. Three separate aeration basins operate in series. Wastewater flows through an anoxic basin followed by two aerobic basins. Immediately following the aeration basins, the wastewater flows through a separate basin containing the membrane bioreactors (MBR) which provide ultra-filtration. The micro-perforated membranes allow treated water to enter the membranes and exclude particles as small as 0.02 microns (µm). The micro-perforations are small enough to filter out bacteria from the final effluent. Water from the membrane bioreactor flows to the contact chamber for hypochlorite disinfection, then is pumped to either the outfall or is used as reclaimed water.

2 Addendum to the Fact Sheet for City of Blaine WWTP Page 2 Membrane bioreactor treatment plants are classified as Class III when flows are greater than one million gallons per day (MGD) and less than 10 MGD. The LPWRF has a design capacity of 1.54 MGD and therefore classifies as a Class III facility. The City must staff the plant with at least one operator certified with a minimum Class III operator certification by the state of Washington. The Class III operator must be in responsible charge of the day-to-day operations of the plant. An operator certified for at least a Class II plant must be in charge during all regularly scheduled shifts. Outfall Blaine will pump reclaimed water from the LPWRF across the spit in the segmented ductile iron pipe that previously carried sewage across the mouth of the harbor. This pipe connects to the existing outfall where reclaimed water from the LPWRF and effluent from the RBC plant will discharge through the existing outfall. Total marine discharge flow will not increase significantly, and the mixing zone will remain the same. Existing effluent limits for the RBC facility will not change except the limit for residual chlorine. The residual chlorine limit is reduced and applies to the single outfall used by both facilities. The proposed permit modification also adds limits for the discharge from the LPWRF. Effluent Limits The limits for the RBC plant will remain the same. The LPWRF will receive technology-based concentration limits of 30 mg/l (385.3 lbs/day) as average monthly limits for BOD and TSS. Technology-based limits are those included in federal law (40 CFR) and are based on the ability of secondary treatment to treat domestic wastewater. Ecology determined the mass limits for the LPWRF by using the following formula: Monthly Max Flow (1.11 MGD) X 30 mg/l X 8.34 = (278) lbs/day Monthly average. Monthly Max Flow (1.11 MGD) X 45 mg/l X 8.34 = (417) lbs/day Weekly average MGD is the monthly maximum design flow for the combined flow of the RBC plant and the LPWRF plant. The LPWRF is designed to handle the entire 1.54 MGD and the mass loading will be assigned to that plant when the RBC is decommissioned. The proposed technology-based limit for fecal coliform bacteria is 200 CFU/100 ml for a monthly average. Ecology conducted a reasonable potential analysis to determine if the discharge would violate the water quality criteria and determined that it needed to include a water quality-based limit for chlorine. Total residual chlorine will have water quality-based limits of 0.12 mg/l for an average monthly limit and 0.25 mg/l as a daily maximum limit. Since effluent from both plants will combine and be discharged from Blaine s one outfall, there is no longer a need for a chlorine limit for the RBC plant. MBR systems are a form of tertiary treatment providing treatment beyond what federal and state regulations require. The effluent meets reclaimed water standards and if used in this way must contain a minimum of 0.5 mg/l residual chlorine concentration at all locations within the reclaimed water distribution system. If effluent is used as reclaimed water, it must meet the minimum residual concentration of 0.5 mg/l while not exceeding 0.75 mg/l. However, when the effluent is discharged through the outfall to marine waters, it must meet the chlorine limits of 0.12 mg/l as an average monthly limit and 0.25 mg/l for a daily maximum. Blaine has identified several reclaimed water uses. Initially reclaimed water will be used to wash down the facility, to flush on-site toilets, and to irrigate landscaping on the facility as well as a nearby park. In the future the City is hoping reclaimed water may be sold to a nearby golf course for irrigation. The following table shows representative characteristics for MBR effluent from a similar treatment facility.

3 Addendum to the Fact Sheet for City of Blaine WWTP Page 3 Effluent Characteristics of the LOTT WWTP in Olympia, Washington Biological Oxygen Demand 5-day mg/l 2.8 Total Suspended Solids mg/l 2.0 ph Standard Units 7.0 Total Nitrogen mg/l Total Coliform #/100 ml 0.0 Design Criteria The proposed permit modification addresses Phase II of Blaine s wastewater treatment and water reclamation plant construction. The City will initially install 12 MBR cassettes at the LPWRF with room for 4 more at full-facility build out. Ecology based the permit modification for the LPWRF on this reduced capacity and not on final plant design capacity. The existing RBC plant discharged an average total effluent flow of MGD from January 1, 2007 to December 1, This flow exceeded the facility design criteria of 0.8 MGD (average maximum monthly flow). While it appears the BOD and TSS mass loading at the RBC plant will increase, loading will in fact decrease since most (approximately 85%) of the City s flow will discharge through the LPWRF. Ecology obtained this information from the Final Facility Plan for the Lighthouse Point Water Reclamation Facility and facility plan drawings. The design criteria listed in permit condition S4.A is based on twenty year projected flows and the ultimate capacity of the LPWRF but is shared between the RBC plant and the LPWRF. Water Reuse Ecology is coordinating with the Department of Health (Health) in issuing this permit modification. This fact sheet addendum explains the nature of the reuse and reclamation treatment, distribution and use, the regulatory and technical basis for Ecology s decisions. The Reclaimed Water Act, Chapter RCW, authorized the development of Water Reclamation and Reuse Standards for the beneficial use of reclaimed water. Health and Ecology completed these in All reclaimed water permits issued by Ecology and Health must specify conditions demonstrating that the wastewater has been adequately and reliably treated to meet the requirements in the 1997 Water Reclamation and Reuse Standards appropriate for the intended use. In addition to meeting the water quality limits, the standards require specific treatment and disinfection requirements beyond those of most conventional wastewater treatment facilities. The standards also require automated alarms, redundancy of treatment units, emergency storage, stringent operator training requirements, and public notification of reclaimed water use. Under the Reclaimed Water Use Act, Ecology or Health issues a permit to the generator of the reclaimed water who may then distribute the water subject to the permitted provisions governing the location, the water quality, and purposes of use. RCW states that a permit is required for land application of reclaimed water. Ecology is issuing the permit modification under the authority of Chapters RCW and RCW. Health may issue a permit for industrial and commercial uses of reclaimed water under the authority Health s permits will govern the location, rate, water quality, and purposes of use. Per memorandum of agreement between Ecology and Health, Ecology includes Health s requirements in a single permit. 1 The LPWRF is expected to have an effluent total nitrogen concentration of 10 mg/l

4 Addendum to the Fact Sheet for City of Blaine WWTP Page 4 In addition to the Water Reclamation and Reuse Standards, regulations adopted by Washington State include procedures for issuing permits (Chapter WAC). The Reclaimed Water Act, the Water Reclamation and Reuse Standards, and these regulations establish the basis for reclaimed water limits and other requirements that are included in the permit. Ecology included reclaimed water limits, monitoring, reporting, distribution, and operation and maintenance in new sections R1 through R5 that reflect Blaine s reclaimed water quality. The City plans to produce Class A reclaimed water, the highest of four reclaimed water classes. Class A reclaimed water is at all times oxidized, coagulated, filtered, and disinfected wastewater. Oxidized means stabilized wastewater such that BOD and TSS do not exceed 30 mg/l that is not putrescible, and contains dissolved oxygen. Coagulated wastewater means a facility adds chemicals to an oxidized wastewater to destabilize and agglomerate colloidal and finely divided suspended matter prior to filtration. Facilities may use an alternative to chemicals if equally effective. In this case it is not likely that coagulating chemicals would be used due to the ultra filtration provided by the MBR. Filtered wastewater means an oxidized, coagulated wastewater which has passed through natural undisturbed soils or filter media, such as sand or anthracite, so that the turbidity as determined by an approved laboratory method does not exceed an averaged operating turbidity of 2 nephelometric turbidity units (NTU), determined monthly, and does not exceed 5 NTU at any time. Adequate disinfection means the median number of total coliform organisms in the wastewater after disinfection does not exceed 2.2 organisms per 100 milliliters (ml). As determined from the bacteriological results for the last seven (7) days for which analysis have been completed, and the number of total coliform organisms does not exceed 23 organisms per 100 ml in any sample. Blaine prefers to use the membrane filtration method to determine bacteriological results of disinfection to obtain a direct count of organisms, rather than the statistical analysis of the most probable number (MPN) method. Membrane filtration is an acceptable and widely used method. The 1997 Water Reuse Standards do not currently provide an equivalent standard to determine adequate membrane filtration for Class A reclaimed water. California established a technology-based membrane filtration standard requiring the effluent turbidity to be at or below 0.2 NTU more than 95 percent of the time and never to exceed 0.5 NTU. A properly maintained and operated membrane would consistently achieve these levels. Turbidity above these levels could indicate a breach or bypass of the membrane process. Therefore, until Ecology and Health revise the Washington State Standard, the Permit Writer s Manual recommends using the California criteria as equivalent to meet the coagulation and filtration steps required for Class A applications of reclaimed water. All industries within Blaine s city limits requiring discharge permits have permit coverage. The proposed permit modification includes limits applicable to distribution of Class A reclaimed water to private entities for commercial and industrial uses and/or to apply reclaimed water for irrigation at agronomic rates. The proposed permit modification authorizes specific reclaimed water uses in Permit Condition R4B, including on-site for flushing toilets, as part of an on-site water feature, to fill applicable city-owned utility vehicles (e.g. water trucks), and for plant wash down. In the future, Blaine may request a permit modification to allow it to irrigate a nearby golf course. The City will discharge excess plant effluent to Semiahmoo Bay for disposal as wastewater in compliance with all applicable NPDES requirements.

5 Addendum to the Fact Sheet for City of Blaine WWTP Page 5 Monitoring Requirements and Permit Reapplication Blaine plans to suspend operations at its RBC plant in the future. As long as the City operates both facilities, it must monitor according to permit condition S2, monitoring requirements, and reclaimed water conditions R2, reclaimed water monitoring requirements. The proposed permit modification requires the City to notify Ecology in writing at least 60 days prior to shutting down the RBC wastewater treatment plant. Within 60 days after the RBC facility stops operating, Blaine is required to provide Ecology with a report detailing the last day of operation and the closure procedures. When Blaine takes the RBC facility off-line and it ceases to produce effluent, it may discontinue monitoring. The City of Blaine and the Department of Health have reviewed the fact sheet and draft permit for factual accuracy. After the public comment period has closed, Ecology will summarize the substantive comments, provide responses to each comment, and publish it when issuing the final permit as an appendix to the fact sheet addendum. Ecology sends a copy of its responses to all those parties who commented on the documents. Ecology will not revise the rest of the fact sheet, but the full document will become part of the legal history contained in the facility s permit file. III. PUBLIC INVOLVEMENT INFORMATION Public notice of the availability of the draft modified permit is required at least 30 days before the permit is modified [Washington Administrative Code (WAC) (3) and WAC ]. The fact sheet and draft permit are available for review (see Appendix A Public Involvement Information of the original fact sheet for more detail on the public notice procedures). After the public comment period has closed, Ecology will summarize the substantive comments and the response to each comment. The summary and response to comments will become part of the file for the permit and parties submitting comments will receive a copy of Ecology s response. Comments and the resultant changes to the permit will be summarized in this addendum. Ecology placed a Public Notice of Modification (PNOM) on April 30, 2010, in The Bellingham Herald to inform the public and to invite comment on the proposed draft modified NPDES permit and fact sheet. The notice Told where copies of the draft permit and fact sheet are available for public evaluation (a local public library, the closest regional or field office, posted on our website). Offered to provide the documents in an alternate format to accommodate special needs. Asked people to tell us how well the proposed permit would protect the receiving water. Invited people to suggest fairer conditions, limits, and requirements for the permit. Invited comments on Ecology s determination of compliance with anti-degradation rules. Urged people to submit their comments, in writing, before the end of the comment period. Told how to request a public hearing of comments about the proposed NPDES permit. Explained the next step(s) in the permitting process.

6 Addendum to the Fact Sheet for City of Blaine WWTP Page 6 Ecology has published a document entitled Frequently Asked Questions about Effective Public Commenting which is available on our website at: You may obtain further information from Ecology by telephone or by writing to the address listed below: Water Quality Permit Coordinator Department of Ecology Northwest Regional Office th Avenue SE Bellevue, WA Telephone: (425)

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9 Addendum to the Fact Sheet for City of Blaine WWTP Page 9 Response to Comments

10 Addendum to the Fact Sheet for City of Blaine WWTP Page 10 Comments regarding the permit modification and fact sheet were received from the Permittee. The majority of the comments were due to a lack of review by the Permittee since the new facility was due to be operative during the month of June. During the public comment period the facility completion schedule changed. Comment #1: Permit condition S1.A (page 8) entitled Effluent Limits LPWRF : The effluent loading limits for BOD and TSS (both average monthly and average weekly) are based on 1.11 MGD maximum month flow. This is the current (year 2009) anticipated maximum month flow for the LPWRF. The facility design capacity for the maximum month flow is 1.54 MGD. This results in an average monthly permit load of 1.54 MGD X 30 mg/l X 8.34 = 385 lbs/day for BOD and TSS, and a weekly permit load of 1.54 MGD X 45 mg/l X 8.34 = 578 lbs/day for BOD and TSS. The maximum month design flow value of 1.54 MGD listed in LPWRF facility drawings is for the combined flows from both east and west Blaine. Since the LPWRF will be treating just the flow from east Blaine, which is listed in facility design documents as 1.11 MGD the original calculations of: 1.11 MGD X 30 mg/l X 8.34 = #/day 1.11 MGD X 45 mg/l X 8.34 = #/day will remain in the modified permit. Comment #2: Permit condition S2.A (pages 9-11): For monitoring requirements the current effluent sampling for all samples except chlorine residual and fecal coliform are set up to be at the LPWRF before chlorine addition. Would it be acceptable to change the sampling point for these samples to read, final effluent before chlorination? Taking samples for BOD before chlorination is appropriate since the sample then does not require de-chlorination. Sampling for TSS prior to chlorination generally is not appropriate unless the sample is taken down stream of ultra-filtration. The MBR is a form of ultra-filtration so in this case it is appropriate to allow sampling for TSS prior to chlorination. The comment did not specifically address ph sampling, but it would be inappropriate to sample ph after chlorination. Change made Comment #3: Permit condition S2.A (pages 9-11): The monitoring schedule chart requires a series of analyses be performed on July 1, 2011 and December 1, The sample location is listed as final effluent. Is this to be done on both plants individually of just LPWRF effluent? The samples required are to be taken on final effluent before chlorination, before it enters the outfall. Comment #4: permit condition #S3.H (page 15): This condition requires a copy of the permit to be kept at the facility. Probably should be kept at both facilities. This permit condition has been changed to require a copy of the permit to be kept at each facility. Comment #5: Permit condition S2.A (page 10): For chlorine residual, would it be allowable to use the Hach Model Cl17 continuous residual instrument for continuous residual measurement instead of a grab sample using the manual measurement? As long as the instrument is calibrated according to the manufacturer and checked regularly, the Hach Cl17 can be used to measure chlorine residual. Change made.

11 Addendum to the Fact Sheet for City of Blaine WWTP Page 11 Comment #6: Permit condition S4.A (page 16): The design influent loading criteria for the LPWRF are presented as the design criteria for year 2009 (the design criteria anticipated for plant start-up). The design capacity influent loadings are: Maximum Month Flow 1.54 MGD Maximum Month BOD Load 3,060 lbs/day Maximum Month TSS Load 3,000 lbs/day Ecology used the projected flows with the current sewer system to limit the allowable loading from the LPWRF. A portion of the 1.54 MGD is processed at the RBC. When the sewer system is reconfigured and the RBC is taken off line the loading associated with the entire 1.54 MGD will be assigned to the LPWRF. Change made. Comment #7: Permit condition R1 (page 29): The Reclaimed Water Limits table lists the average monthly flow as 1.11 MGD. The design average maximum month flow is 1.54 MGD. Ecology notes that this correction as the RBC plant is not a factor in the Water Reclamation Plan the entire flow of 1.54 MGD has been allocated to the LPWRF. Change made. Comment #8: Permit condition R1 (page 30): The Reclaimed Water Limits table lists the point of compliance at the east end of the LPWRF. For BOD, TSS, and DO, we feel the appropriate sampling location is the current final effluent sampler at the east end of the plant. However, we feel a more appropriate grab sample location for compliance monitoring of chlorine and coliforms may be at the west end of the facility where the 4 reclaimed water (RW) pipe re-enters the treatment plant. Ecology discussed this with the City of Blaine. Blaine intends the length of pipe running from the east end of the building to the west to act as part of the chlorine contact time required by Ecology. Change made. Comment #9: Permit condition R1 (page 30): The Reclaimed Water Limits table lists DO to be continuously monitored. Current plant design does not include continuous DO monitoring of the final effluent. Is continuous monitoring required, or would a daily grab sample be sufficient? Reclaimed Water regulations contained in WAC WAC (2)(b) states that one of the conditions of Class A reclaimed water is that, Dissolved oxygen must be measured within the biological oxidation process and must be present in all samples. The Water Reclamation and Reuse Standards state in article 7, section 1, Protocols and Minimum Frequencies, (e), grab samples for dissolved oxygen shall be collected at least daily and at a time when wastewater characteristics are most demanding on the treatment facilities. A daily grab sample will be sufficient. Change made. Comment #10: Permit condition R1 (page 30): The Reclaimed Water Limits table lists that coliforms should be measured and reported as MPN/100 ml. This indicates that the multiple tube fermentation technique is required. Class A reclaimed water monitoring table on page 31 indicates that coliforms are to be reported as # of organisms/100 ml, which indicates a direct colony count using the membrane filter technique. The City would prefer to use the membrane filter technique. Is this acceptable?

12 Addendum to the Fact Sheet for City of Blaine WWTP Page 12 Ecology understands that using two different techniques to obtain very similar outcomes would be unnecessarily expensive. Both methods are approved by EPA and Ecology. The City has been performing fecal coliform testing using membrane filtration at its RBC plant, and Ecology sees no reason why the City cannot continue at its new facility. Change made. Comment #11: Permit condition R2.A (page 31): The Reclaimed Water Limits table indicates that all samples should be measured, daily, weekly, etc. Only chlorine residual is required, when in use. It appears that it would be appropriate to measure all parameters when in use. Is this acceptable? Ecology used this terminology because the city had indicated that it did not anticipate that reclaimed water would be used all year around. The City plans to use reclaimed water for flushing toilets in public restrooms, and for an outdoor water feature, as well as seasonal irrigation at a city park next to the new waste water plant. Ecology thinks it is appropriate to use, when in use since the use won t be seasonal or continual. All parameters except flow are listed as when in use. No flow should still be reported when reclaimed water is not in use.. Comment #12: Permit condition R4.A (page 34): The Reclaimed Water system average flow at the maximum month is listed as 1.11 MGD. The plant capacity at the maximum month is Ecology has noted and made this change. Comment #13: Permit condition R5.B (page 39): Reclaimed Water System Maintenance. Item two states; A chlorine residual of at least 0.5 mg/l shall be maintained in the reclaimed water during conveyance from the reclamation plant to the use area unless waived by the Departments of Health and Ecology. Item three states; Maintenance of a chlorine residual is not required in reclaimed water impoundments and storage ponds. At the discretion of the Departments of Health and Ecology, chlorine residual may not be required in reclaimed water distributed from storage ponds. Item two addresses the piping, or conveyance, from the reclamation plant to the use area. Item three addresses a separate issue of impoundments and storage ponds. Ecology has added an underline in the permit under, during conveyance from the reclamation plant to the use area. Comment #14: The addendum to the Fact Sheet, II. Effluent Limits (page 2): The calculation for effluent loading limitations is performed using a maximum month flow of 1.11 MGD. The actual design flow is Ecology has noted and clarified that the loading associated with 1.54 MGD is to be split between the LPWRF and the RBC plant. Comment #15: The addendum to the Fact Sheet, II. Effluent Limits (page 2): Total residual chlorine limits for the final effluent are currently listed as a single grab sample at the combined outfall location for both treatment plants. The new treatment plant has continuous monitoring of total residual chlorine using a Hach Model Cl17 residual chlorine analyzer. We recommend that the chlorine residual be measured for both treatment facilities individually continuously at LPWRF and using an outfall grab for the RBC facility. We d recommend the combined residual can then be calculated using the following equation:

13 Addendum to the Fact Sheet for City of Blaine WWTP Page 13 (LPWRF ave. daily residual chlorine mg/l) X (LPWRF ave. daily flow MGD) + (RBC grab sample residual chlorine mg/l) X (RBC ave. daily flow MGD) Divided By (LPWRF ave. daily flow MGD) + (RBC ave. daily flow MGD) Ecology finds this method acceptable to determine the total residual chlorine for the final effluent.