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HomeMy WebLinkAboutCOM 0284.000 2000-2002 010587 July 19, 2001 Mr. Dennis K.W. Lee, P.E. Director of Engineering , Department of Public Works County of Hawaii 25 Aupuni Street Hilo, Hawaii 96720 Dear Mr. Lee: Subject: Kealakehe Wastewater Treatment Plant Operation and Maintenance Inspection Attached for your information and use is our Operation and Maintenance Inspection Report for the subject facility. The inspection was conducted on June 21, 2001. The facility is given an overall rating of "UNACCEPTABLE" because the reuse projects have not been constructed. Plant effluent continues to be disposed of into the "temporary" percolation pond. Other deficiencies are cited in the attached report. Please submit, within 60 days of receipt of this letter, a corrective action plan addressing the noted deficiencies. A reasonable time schedule for completion of the plan actions should also be included. If you have any questions, please call Steven Sato of our Wastewater Branch at direct toll free no. 974-4000, ext. 64294. Sincerely, L~ . THOMAS E. ARIZUMf/~E. CHIEF Environmental Management Division Ss:erm Attachment / Comm. No. c: Y County Council Public Works Chairperson, (w/report} EPA Region IX, Attn: Tom Huetteman, (w/report) File No. DDEH, (w/report) Ref. '~O' ~4~t~AUG OPERATION AND MAINTENANCE INSPECTION REPORT INTRODUCTION 1. Facility: Kealakehe Wastewater Treatment Plant 2. Date of Inspection: June 21, 2001 3. Inspector(s): Steven Sato 4. Facility Representative(s) / Job Title: Mark Norman / WWTP Operator III BACKGROUND 1. Current status of deficiencies cited in previous inspection reports: Deficiency: The County needs to accelerate implementation of the reuse projects. DOH letter dated July 23, 1999 to Mr. Jiro Sumada of the County of Hawaii's Department of Public Works, requested the County to submit a revised and realistic construction schedule for the effluent projects. To date, DOH has not received any written official response from the County. Status: A revised construction schedule for the effluent reuse projects was submitted by the County in August 1999. The Contractor Fill Station project which was scheduled to be completed by December 2000 has not yet been constructed. The Highway Transmission Pipe project has been put on hold due to delays in the State Department of Transportation's Queen Kaahumanu Highway widening project. This project will enable the reuse of effluent for irrigation of landscaping at Honokohau Harbor and along the access road between Kaahumanu Highway and Honokohau Harbor, which is required to be constructed under the terms of the Consent Order for Docket No. 90- WW-EO-10 (DOH v. County of Hawaii), and originally required to be completed by October 31, 1998. The County has twice requested and been given extensions of the deadline. The current extended deadline for the Kealakehe WWTP Operation and Maintenance Inspection Report July 19, 2001 Page 2 project's completion is August 2002. Also; the Reservoir and R-1 Upgrade projects are also behind schedule. Currently reported to be in progress is the design phase of a Demonstration Wetlands project. Deficiency: The chlorinator has been malfunctioning since May 2000. The chlorine gas feed rate was fluctuating, resulting in unreliable readings. Meeting chlorine residual requirements for R-2 water quality has been very difficult for the operators to achieve. The laboratory data showed an increasing trend in fecal coliform values since the time of chlorinator malfunctions. The reuse of effluent at the "Swing Zone" driving range was suspended on May 29, 2000. Status: A new tank-mounted vacuum regulator chlorinator was installed and since then the facility has had no problems in meeting the chlorine residual requirements for R-2 water quality. The reuse of effluent at the "Swing Zone" was resumed on July 7, 2000. Deficiency: Grit Classifier No. 2 was removed from service in February 2000 due to corrosion problems. To date, completion of the repair work on the classifier is still uncertain. Status: The grit classifier was sent to an outside contractor approximately two months ago. The unit is being rebuilt using stainless steel. Deficiency: The motor cage of the grit chamber turntable motor was noted to be heavily corroded. The cage housed the rotating shaft of the motor. For safety and Liability reasons it is recommended that the cage be repaired. Status: The corrosion on the motor cage was not as severe as it appeared. Corrosion was removed by wire-brushing and the motor cage was repainted. Deficiency: Effluent Pump No. 3 became inoperable on April 12, 2000. The impeller head bonded to the casing, causing the motor to be overloaded. The run time of the pump was only 3, 000 hours. The Kealakehe WWTP Operation and Maintenance Inspection Report July 19, 2001 Page 3 two remaining effluent pumps are expected to reach the 3,000-hour run time by the end of this year. Considering that the pumps are relatively new, the County should investigate the cause of the problem. Status: The cause of the problem was determined to be due to a build-up of corrosion on the bell housing, resulting in binding of the impeller and subsequent overloading of the motor. A purchase order was issued for the repair and modification work on Effluent Pump No. 3 on May 31, 2001. Modifications included the installation of a stainless steel wear ring in the casing, replacement of the column and lineshaft tube with stainless steel piping, and conversion from an oil lubricated system to a grease lubricated system. The pump was placed back in service and a problem with air suction into the pump was encountered. The County is presently considering the installation of a new mechanical seal to contend with the problem. Effluent Pump Nos. 1 and 2 also need to be modified, but the work will not be done until the modifications to Pump No. 3 have been demonstrated to be effective. Deficiency: Safety railings should be provided at the stairs at the effluent pump station. The operators use the stairs to open the valves. Status: Railings were installed on the stairs and platforms located at the Effluent Pump Station. The work was completed on August 25, 2000. Deficiency: Chain Links should be installed around the influent channel to prevent personnel from accidentally falling into the channel. Status: A Hawaii Occupational Safety and Health Division (HIOSH) Consultation Advisor performed a Safety Survey of the facility on May 25, 2000. The Consultation Advisor determined that the facility's current method of cordoning off the access stairway to the influent channel area with a chain is sufficient to meet HIOSH requirements. Kealakehe WWTP Operation and Maintenance Inspection Report July 19, 2001 Page 4 Deficiency: The temperature reading at the blower's suction was slightly over 100 degrees Fahrenheit. Heat could damage the blowers. Status: A large portable fan was installed at the blower room as a temporary corrective measure. A long-term fix is now being designed. 2. NPDES Permit Status: Not applicable. 3. Enforcement Action: The County is under a Consent Order, Docket No. 90-WW-EO-10, Department of Health v. County of Hawaii, which became effective on March 13, 1997. The terms of the Consent Order require the County to construct a reuse system to use properly treated effluent to irrigate landscaping at Honokohau Harbor and along the access road between Kaahumanu Highway and Honokohau Harbor. The consent order deadline for the project's completion was October 31, 1998. On February 24, 1998 the DOH approved a County request for an extension of the deadline to August 2000. On November 24, 1999 the DOH approved another County request for an extension of the deadline to August 2002. 4. Capacity Analysis: Average flow: 1.44 MGD (For the period 5/1/00 to 4/30/01) Design flow: 5.31 MGD; Percent of design capacity: 27% Previous year's comparison: Last year's flow averaged 1.30 MGD. This year's flow is averaging about 140,000 gpd more and is reportedly due to additional sewerline connections. Kealakehe WWTP Operation and Maintenance Inspection Report July 19, 2001 Page 5 5. Influent/Effluent Data Analysis: (Based on monthly averages for May 2000 through April 2001) Influent BODS: 277 mg/1 (grab sample) Effluent BODS: 6.1 mg/1 (grab sample) Influent TSS: 148 mg/1 (grab sample) Effluent TSS: 17 mg/1 (grab sample) pH (min.): 6.9 (grab sample) pH (max.): 9.2 (grab sample) Effluent limits are 30 mg/1 and 30 mg/1 for BODS and TSS, respectively. The reclaimed water guidelines for R-2 water require the following: a. The median density of fecal coliform bacteria measured in the disinfected effluent does not exceed 23 per 100 milliliters based on the last seven days for which analyses has been completed. Review of the facility's recorded data revealed no violations. b. The density of fecal coliform bacteria does not exceed 200 per 100 milliliters in more than one sample in any 30-day period. Review of the facility's recorded data revealed no violations. c. Chlorine residual in the disinfected effluent shall not be less than 0.5 mg/l. Review of the facility's recorded data revealed no violations. Kealakehe WwTP Operation and Maintenance Inspection Report July 19, 2001 Page 6 6. Modifications/Additions - Planned/Present Construction Status: Effluent Pump No. 3 was modified with a stainless steel insert and riser pipe. The County also has reuse projects planned for construction as previously noted in this report. CURRENT INSPECTION 1. Maintenance: Preventive Maintenance: X Current Backlogged Comments: Preventive maintenance (PM) duties are all up-to- date. PM duty schedules are listed on separate weekly, monthly, quarterly, semi-annual, and annual sheets and stored in a 3-ring binder. The operator checks off, dates, and initials the completed duties. Corrective Maintenance: X Satisfactory Unsatisfactory Items requiring repair/replacement: 1. Grit Classifier No. 2. 2. Chlorine motive water line burial. 3. Grit Pump No. 1. Comments: The completed corrective maintenance work order sheets are not completely filled out. Man-hours and parts used are not recorded on the work order sheets. 2. reuse: The facility has a DOH approved effluent irrigation plan: X Yes No Not applicable Comments: Effluent is currently reused only at the "Swing Zone" driving range. Kealakehe WWTP Operation and Maintenance Inspection Report July 19, 2001 Page 7 3. NPDES or Chapter 62 Violations (effluent limitations, spills, etc.) There were no violations noted. 4. Visual quality of effluent on date of inspection (inspector's judgment) The effluent was observed to be relatively clear and light-green in color. 5. Facility's Present Deficiencies: a. The County continues to utilize the temporarily approved seepage pit for effluent disposal. Effluent reuse projects have been slow to materialize. b. Grit Classifier No. 2 is still under repair. c. Grit Pump No. 2 is inoperable. SLTiKI~ARY 1. General Rating: ACCEPTABLE CONDITIONAL ACCEPTANCE X UNACCEPTABLE Explanation: The Kealakehe WWTP is given this rating because the County continues to utilize the temporarily approved seepage pit for effluent disposal. Also, very little progress has been made in construction of the reuse projects. 2. General Comments / Recommendations: We have the following recommendations: 1. Performance of process control analyses should be periodically conducted at various points throughout the Kealakehe WWTP Operation and Maintenance Inspection Report July 19, 2001 Page 8 treatment ponds. As a best management practice, the recordation of weather conditions, pond color, pH, and dissolved oxygen is recommended. Also, periodic identification of the ponds' active microorganisms should also be recorded. Should changes in effluent quality occur, the recorded data could help the operator in identifying and correcting the trouble source; 2. Chemical testing for moisture accumulation at the bottom of the underground fuel storage tank should be conducted monthly; and 3. Man-hours and cost of parts utilized should be logged on the work order sheets for historical reference.