Attached as requested. Please let me know when you've heard back from Bob Kaplan because Jo
Anne Rennaker is leaving by early afternoon today, so I’m planning to help her out with finaling this
letter. Thanks.
xxxEND_PAGE:deq20_b02_058_173_051
STATE OF MICHIGAN =
DEPARTMENT OF ENVIRONMENTAL QUALITY DESs.
LANSING DISTRICT OFFICE
RICK SNYDER DAN WYANT
GOVERNOR DIRECTOR
October 30, 2015
Mr. Mike Glasgow
Utilities Administrator
City of Flint
4500 North Dort Highway
Flint, Michigan 48505
Dear Mr. Glasgow:
SUBJECT: Water Supply — City of Flint (City) - i Yr ent Operation
is and recommendations regarding
en by the City water system.
The purpose of this letter is to outli
the additional corrosion control treatn
The City has been purchasi 9 drinking and Sewerage Department
(DWSD)/Great Lakes 6, 2015. DWSD/GLWA
provides corrosion c re i it IWSD/GLWA has been deemed by the
r fully optimized corrosion control
to provide orthophosphate addition,
g/L) as POs, and maintain a
4. AS part of its optimization, DWSD/GLWA
ity water distribution system, customer service
City shall dose additional orthophosphate to increase
sidual to a minimum of 3.1 mg/L as PO, (1.0 mg/L as P).
Control Station 2 and Pum
October 28, 2015.
tion 4, construction permit number W151104, issued on
The City should also maintain a minimum pH level of 7.0 throughout the City’s water distribution
system. If pH levels of 7.0 or less are detected, the City shall immediately notify the MDEQ.
As part of the City water system operations, the City shall conduct:
- Daily monitoring of incoming DWSD/GLWA water for pH and for orthophosphate
residual, as PO,
- Daily monitoring of additional orthophosphate dosage, as PO,
- Daily monitoring of water entering the City distribution system for pH and for
orthophosphate residual, as PO,
CONSTITUTION HALL * 525 WEST ALLEGAN STREET * P.O. BOX 30242 * LANSING, MICHIGAN 48909-7742
www. michigan.gov/deq « (617) 335-6010
xxxEND_PAGE:deq20_b02_058_173_052
Mr. Mike Glasgow 2 October 30, 2015
This information shall be included in the City’s monthly operation report and shall be reported to
the MDEQ as required under Administrative Rule 1502 (R 325.11502) of the administrative rules
promulgated pursuant to Act 399.
Enhanced Water Quality Parameter Monitoring
The City’s revised monitoring schedule dated October 22, 2015, requires quarterly Water
Quality Parameter Monitoring at 25 sites throughout the City’s water distribution system for
temperature (Celcius), Conductivity (mS), pH, Total Alkalinity (mg/L as CaCQs), Calcium (mg/L
as Ca’), and orthophosphate (mg/L PO,). Ten of these 25 sites are also used by the City to
conduct required total coliform bacteria and chlorine residual monitoring (location numbers 1, 2,
3, 4, 5, 6, 7, 8, CS, and WS). At these ten locations the City shall also conduct weekly
monitoring for the following parameters at the same time that total coliform bacteria and
chlorine residual monitoring is conducted to further assess water stability:
- Turbidity (NTU) - Calcium (mg/L as Ca”*)
- Iron (mg/L) - Chloride (mg/L as CI)
- Orthophosphate (mg/L PO,) - Temperature (Celcius)
- pH - Conductivity (mS)
- Total Alkalinity (mg/L as CaCO;)
If orthophosphate residual levels less than 3.1 mg/L as PO, (1.0 mg/L as P) are detected at any
of these locations, then orthophosphate dosage shall be increased to achieve the minimum
phosphate residual of 3.1 mg/L as PO, (1.0 mg/L as P) at all locations. In addition, if pH levels
of 7.0 or less are detected at any of these locations, the City shall immediately notify the MDEQ.
Corrosion Control Treatment Test Loops
To further confirm the effectiveness of corrosion control treatment and the City’s operations, it is
recommended that the City construct, install, and monitor test loops of service line and plumbing
materials. Instructions for construction, installation, and monitoring of these test loops can be
obtained from the United States Environmental Protection Agency’s (U.S. EPA) Office of
Research and Development. Please contact Mr. Darren Lytle, Acting Branch Chief, at
512-569-7432 or
[email protected].
Lead Service Line Verification Sampling
The City has been reviewing customer service connection records in order to confirm customer
service line materials at each connection. The U.S. EPA has developed a sampling procedure
that can be used to help verify the presence of lead service lines and it is recommended that the
City conduct this sampling at a selection of customer locations for this purpose. Information
regarding this verification sampling can also be obtained from Mr. Lytle. Any water analysis for
lead and copper is expected to be completed by a certified lab.
Customer Household Exposure Assessment
The Michigan Department of Health and Human Services (MDHHS) is continuing to conduct
blood lead level testing for children in the City. Families with children found to have elevated
blood lead levels will be asked to have an elevated blood lead level investigation conducted at
their residence that will include a lead exposure assessment, including the contribution of lead