HomeMy WebLinkAboutCOM 0649.000 1998-2000 RECEIVED 7-~~
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County Council r
January 18, 2000 zooozz
Mr. Robert Yanabu
Chief Engineer
Department of Public Works
County of Hawaii
25 Aupuni Street
Hilo, Hawaii 96720
Dear Mr. Yanabu:
Subject: Hilo Wastewater Treatment Facility
Operation and Maintenance Inspection
Attached for your use is our annual Operation and Maintenance
(O&M) Inspection Report for the subject facility. Department of
Health staff inspected the subject wastewater facility on
August 19, 1999. The facility is given an "Unacceptable" rating
based on the deficiencies cited in the report.
Please respond within thirty (30) days after receipt of this
letter with an affirmative action plan addressing the
deficiencies noted. A'reasonable time schedule for the
correction of the deficiencies should also be included.
Should you have any questions, please call Sina Steffany of our
Wastewater Branch at our direct toll free no. 974-4000 extension
64294.
S~ce"rely~
THOMAS E. ARIZUMI, P.E.
Chief, Environmental Management Division
SLS:jc
Attachment
c: EPA, Region IX (Attn: Mr. Tom Huettman)
~COUnty Council Public Works Chairperson
DOH, Clean Water Branch /
Comm. No. 10
File No. 'S~w
Ref. To: Pwl c/
Ref. Date FFR 0 ? ~~9
OPERATION AND 1[AINTENANCH INSPECTION AEPOAT
INTRODIICTION
Faailitys Hilo Wastewater Treatment Plant
Date(s) of inspection: August 19, 1999
inspector(s): S. Steffany, DOH Wastewater Branch
Facility Aeprssentative(s)/Job Title:
Lyle Hirota, WWTP Superintendent
Andy L. Narido Sr., WWTP Supervisor (TA)
BACKGROUND
i. Current status of deficiencies cited in previous inspection reports:
Deficiency: Infiltration/Inflow (I/I) continued to impact plant
operations during the past year as noted by the low
influent BODE/TES. As such, the facility was having
difficulties in meeting its 85 percent removal permit
requirement for BODE. However, with the completion of
the Bayfront Sewer Line Rehabilitation Project, the i/I
problem should lessen.
Status: Grout sleeve equipment vas purchased and the County is
in the process of purchasing chemical grouting
equipment to reduce I/I. Aeducinq I/I vill be a on-
going project.
Deficiency: The influent sampler tube bracket had completely
corroded away detaching the tube from the wall. This
condition subjects the tube to downstream displacement
caused by turbulence from the Pua Pump Station
influent. A sidestream return line located downstream
of the sample point may contaminate the influent
sample. The influent sample tube must be resecured.
Status: The influent sample tube vas resecured.
Deficiency: The refrigerated influent sampler at the headworks was
unlocked. NPDES samples must be kept locked to prevent
possible tampering by unauthorized personnel.
Status: The influent sampler unit has been locked.
Deficiency: Influent screen no. 2 was inoperable awaiting repairs.
Status: Repairs to the barscreen ware completed.
2
Deficiency: The design problem relating to water intrusion of the
foul air piping at the headworks is still outstanding.
Foul air is not being removed and treated as originally
designed.
Status: The eacloaures at the barscreens xer• removed to
eliminate aoafined spans hasard• rhea performing
maintenanoe on the equipment. xo iaareas• in odor
problems resulted. The air piping was blanked off to
prevent rater intrusion. xo lurther cation is
proposed.
Deficiency: Primary clarifier no. 1 has been inoperable 61nce 1995
due to a continually malfunctioning variable frequency
drive (VFD). Efforts to repair the unit have been
unsuccessful. The co-settling mode of operation
requires two of the 3 clarifiers to be on-line at all
times. Therefore, no backup is available should
another clarifier unit break down.
statues The Aastexater Division is evaluatiaq the removal of
the vFD and replacing it xith a gear reduction spstem.
The target completion dat• is 12/30/1999. Broxn i
Caldxell is evaluatiaq this problem and th• target date
may be changed.
Deficiency: The diffusers for the preaeration basin required
replacing due to plugging problems;
Status: The diffusers rill bs replaced. The target completion
dat• 10/30/1999.
Deficiency: Biotower pump nos. 2 and 4 were inoperable awaiting
repairs;
Status: The County has attempted repairs and has a unit at a
local machine shop. One pump rill be replaced and the
other pump rill be svaluated for repair or replacement.
Broxa i Caldxell rill be evaluatiaq this problem. The
target completion dat• is 12/03/2000.
Deficiency: The bent skimmer arm, noted in last year's inspection
report, for final clarifier no. 1 was removed.
Floating sludge clumps were passing through with the
final effluent.
status: Bids for the repair project is currently being
solicited by the County. No target completion date has
been scheduled for this project.
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Deficiency: Final clarifier no. 3 was inoperable due to the pending
repair of sludge pump no. 1. Although only 2
clarifiers are needed at any time, this situation
provided no available backup unit.
Status: The system Mss modified and the szistinq pump Mss
rsplaasd with a submersible pump. No further action is
required.
Deficiency: The effluent flowmeter was last calibrated in October
1997. The County's NPDES permit requires semiannual
calibration or as required by manufacturer's
recommendation, whichever is less. The 1995 inspection
report reminded the County that calibration was
required every 6 months. The 6 month preventive
maintenance sheet should be updated to include this
requirement.
status: The floMmeter is aurrentlp on a f month calibration
schedule.
Deficiency: The packing for the digester sludge mixing pump no. 1
was leaking;
Status: The pump Mas modified and a nechanlcal seal has been
installed.
Deficiency: The waste gas burner does not relight automatically
when the flame goes out.
Statues The system was designed Mith a continuous LPf; flame to
provide sutomatia re-ignition. Ths system will bs re-
designed by a consultant to provide automatic rs-
ignition Mithout a continuous flame. The target
aomplstioa date is 6/30/2000.
Deficiency: Thickened sludge pump no. 2 stator was worn out;
Status: The stator has boon replaced.
Deficiency: Centrifuge no. 1 was inoperable. The bowl needed to be
shipped to the manufacturer for extended repair work.
No backup unit was available.
Status: The County contacted the nanufactursr regarding the
repair of the unit. Humbolt-Decanter informed them
that the loss of tiies Mould result in an aaaslsrated
deterioration of the scrsM conveyor, but that repair of
the screM could be accomplished at the time Mhen
sfficieacy of the unit viii be affected. Ths County
has decided to perform the the replacement Mhen the
efficiency of the unit is affsatad.
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Deficiency: The electrical conduits in the primary MCC room still
have not been painted as noted in previous inspections.
Status: The conduits xere not yet painted. The target
aompletlon date is scheduled for 9/30/1999.
Deficiency: The odor control prechlorination system continues to be
inoperable as noted in previous inspections. Parts
have been removed for use elsewhere in the plant.
Status: The system is not bsinq utilised beaaus• of its high
operating costs and the odor problems not being severs.
Se-evaluation o! the system rill be aacompiished in the
event that odor problems ar• encountered in the future.
Deficiency: As noted in previous inspections, the automatic flow
proportioned chlorinator remains inoperable and the
unit continues to be operated manually on constant
feed. This results in possible over or underfeeding of
the amount of chlorine needed to fully disinfect the
effluent caused by fluctuation in plant flows.
Status: The automatic flox proportioned spates had not been
installed on the dap of the inspection. In a
subsequent letter dated October 11, 1999, the County
stated that the system has been installed and is
operational.
Deficiency: Bacterial sampling results for the effluent are suspect
due to the lack of adequate detention time in the
chlorine contact tank. The sampling station is located
only about 15-feet downstream from the chlorine feed
line.
Status: The County rill perform a dye test to oonfirm detention
times lroa the effluent facility to the old Hilo 8TP
facility. Bacterial and chlorine sampling rill be
performed to ensue MPDES permit requirements are being
met.
Deficiency: Staff vacancies have impacted preventive and corrective
maintenance work at the Hilo WWTP. Current vacant
positions include: a sewer maintenance supervisor, an
assistant operator, and a maintenance technician. In
addition, the WWTP supervisor has been on leave for the
past year due to a workman's compensation case.
Status: The Sexer Maintenance Supervisor's position has been
permanently filled. The County intends to fill the
vacant mechanic and assistant operator positions. A
final resolution of the WWTP Supervisor position is
currently being pursued.
5
Deficiency: Safety - The stairway to the second floor of the
centrifuge room was missing the middle rail. For
safety and liability reasons, a rail should be
installed.
status: J?n additional rail Mas installed.
Deficiency: Safety - The non-potable water warning sign for the
hose station atop the biotower was broken and should be
replaced.
Status: The xarning sign vas replaced.
Deficiency: Security - The main security gate at the access roadway
leading to the plant is not equipped with electrical
power. The gate remains open when the plant is manned.
This is a design deficiency that has not been addressed
by the County.
Status: During work hours the gate remains open and
unauthorised entry is being aonitored by staff on duty.
The gate is locked during nos-xorkiaq hours.
Deficiency: The sewer user charge appears inadequate to cover
annual operation and maintenance costs of the facility.
The 1996/1997 fiscal year (FY96/97) annual report
indicated a shortage in the sewer fund and a portion of
the fund was subsidized by the County's General Fund.
The Hilo WWTP was partially constructed with state and
federal construction grant funds. Federal regulations
40CFRS35.2208 requires grantees to implement an
adequate user charge system and sewer use ordinance
throughout the useful life of the treatment works. The
Hilo WWTP has deteriorated during its 5 years of
operation.
status: The Wastexater Division rill be proposing revisions to
the Haxaii County Cod• to increase the user rates.
Target completion date is scheduled for 6/30/00.
Deficiency: The equipment replacement fund for FY97/98 showed a
balance of $2,052,775 on June 30, 1998. Considering
the equipment problems noted in the inspection report,
a zero ($0) disbursement during the fiscal year is
questioned.
Status: The Wastexater Diviaioa xill be increasing the number
of repairs sad replacement of equipment. The County
xi11 be hiring a sex civil engineer that rill be
responsible for designing and/or contracting the
necessary equipment upgrades or replacement.
6
2. NPDEB Permit 8tatuss
Permit Expiration Date: NPDES Permit HI 0021377 expires at midnight
on August 31, 2000.
Comments: None.
3. Enforcement Actioa:
Status: None.
4. Capacity Aaalysiss
Average flow: 3.4 million gallons per day (MGD) for the period 8/98
to 7/99
Design Flow: 5.0 MGD; Percent of design capacity: 68 percent
Previous year's comparison: Last year's reported flow averaged 3.76
MGD. This year's average flow decreased by approximately 0.36 MGD or
9.3 percent. The recently completed Bayfront Sewer Line
Rehabilitation Project and the dry weather encountered during the past
year may have contributed to the reduction in influent flows.
5. Influent/Effluoat Data Analysis: Based on aont~ly averages
for 08/98 to 07/99.
a. Influent BOD, 74.9 mg/1 (composite)
b. Effluent BOD, 11.5 mg/1 (composite)
c. Influent TSS 99.8 mg/1 (composite)
d. Effluent TSS 12.4 mq/1 (composite)
e. pH (min) 7.0 (grab)
f. pH (max) 7.2 (grab)
Permit limits are 30 mg/L and 30 mg/L for BODS and TSS, respectively.
6. Modifications/Additions - Planned/Present Construction Status:
None.
CURRENT INSPECTION
1. Maintenance: Check either: No. of:
Preventive Maintenance: Current Backlogged
Corrective Maintenance: Satisfactory Unsatisfactory
Major (or all) items requiring repair/replacement:
a. Primary Clarifier No. 1. - Malfunctioning VFD.
b. Grit Screw - Rebuild screw and replace housing.
7
c. Aeration Tank Diffusers - Needs replacement.
d. Centrifuge No. 1 - Tiles are falling off.
e. Biotower Pump Nos. 2 and 4.
f. Final Clarifier No. 1 - No skimmer arm.
2. Aeuse:
The facility has a DOH approved effluent irrigation plan:
_ Yes _ No ~j_ Not applicable.
3. NPDSB or Chapter 62 violations (effluent limitations, spills, etc.):
The 85 percent BOD5 removal rate was not met for the following months:
October and December 1998; March, April, and May 1999.
The chlorine residual limits were exceeded during the months of
February, and May 1999.
4. visual quality of effluent on date of inspection (inapector~s
judgment):
The final effluent appeared clear on the day of the inspection.
S. pacility~s Present Deficienoiess
a. infiltration/Inflow (I/I) continued to impact plant operations
during the past year as noted by the low influent BODS/TSS. As
such, the facility is still having difficulties in meeting its 85
percent removal permit requirement for BODS;
b. Primary clarifier no. 1 has been inoperable since 1995 due to a
continually malfunctioning variable frequency drive (VFD).
Efforts to repair the unit have been unsuccessful. The
co-settling mode of operation requires two of the 3 clarifiers to
be on-line at all times. Therefore, no backup is available
should another clarifier unit break down;
c. The diffusers for the preaeration basin required replacing due to
plugging problems;
d. Biotower pump nos. 2 and 4 were inoperable awaiting repairs;
e. The bent skimmer arm for final clarifier no. 1 still requires
replacement.
f. The waste gas burner was not being used because it does not re-
light automatically when the flame goes out;
8
q. The tiles for Centrifuge No. 1 still requires replacement. The
bowl needs to be shipped to the manufacturer for extended repair
work;
h. The electrical conduits in the primary MCC room still have not
bean painted as noted in previous inspections;
i. During the inspection, boiler #1 had malfunctioned and was placed
out of service;
j. Bacterial sampling results for the effluent are suspect due to
the lack of adequate detention time in the chlorine contact tank.
The sampling station is located only about 15-feet downstream
from the chlorine feed line;
k. The automatic flow proportioned chlorinator remained inoperable
on the day of the inspection. A County letter dated October il,
1999, stated that the system has been installed and is
operational.
1. Staff vacancies continue to impact preventive and corrective
maintenance work at the Hilo WF1TP. Current vacant positions
include: an assistant operator, and a mechanic. Zn addition, the
WWTP supervisor has been on leave for the past two years due to a
workman's compensation case;
m. The sewer user charge still appears to be inadequate to cover
annual operation and maintenance costs of the facility. Federal
regulations 40CFR$35.2208 requires grantees to implement an
adequate user charge system and sewer use ordinance throughout
the useful life of the treatment works;
n. The equipment replacement fund for FY98/99 showed a balance of
$1,909,172 on June 30, 1999. Considering all of the equipment
problems noted above, a $150,000 disbursement during the fiscal
year is questioned; and
o. A discrepancy concerning the process control data for the
biofilter influent was noted. The total suspended solids of the
influent was less than the effluent. Therefore, a negative
removal rate resulted. After discussing this matter with staff
personnel, it was determined that the sampling location of the
influent was not representative of the wastewater entering the
biofilter. Apparently, the sampling point did not include the
sidestream that was recycled back into the biofilter causing a
lower influent concentration to be sampled.
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BIIMMARY
1. cianaral Rating:
ACCEPTABLE CONDITIONAL ACCEPTANCE UNACCEPTABLE
Explanation: The rating is based on the numerous deficiencies that
are noted above. Many of the deficiencies were cited in previous
inspection reports. Efforts should be taken by the County to resolve
these deficiencies in a more timely manner.
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