Jim,
In the interests of time, I am sending over a comment from TF discussions directly. There are a few
technical concerns about the permit issued to Flint. Could you consider the comment below and let me know
your thoughts? It's important to all that we get this nailed down without delaying the feeding of corrosion
control. Thanks.
there is a unit “issue” in the section of phosphate dosages. In our phone call the other day,
DEQ indicate the units discussed were mg/L as P, when we questioned how much phosphate was
being consumed in the Flint system from the Detroit water feed This also came up in a prior
discussion on the phone Darren and I had with DEQ about observations of phosphate loss, even
within Detroit. The recommendations Darren and I provided for an initial dose of a total
amount of PO4 (as PO4), were that the target residual to the estimated theoretical point of
diminishing returns to optimize phosphate (in lieu of having it be determined by actual pilot
testing) should be in the 3-4 mg/L as PO4 neighborhood, closer to 4.
At this time (but not when they change water supplies!) they only need to supplement the PO4
coming from Detroit, Thus, the pumps to be installed should have the minimum capacity to dose
to achieve the 3-4 mg/L as PO4 level (1-1.3 mg/L as P), with extra capacity to achieve 4-6 mg/L
as PO4 (1.3 to 2 mg/L as P), to assure that they could overcome an estimated system pipe wall
demand. So, the design max dosage for the pumps should be 6 mg/L as PO4 — (the minimum
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amount of phosphate received from Detroit, in mg/L as PO4). The minimum would be 3.5 to 5
mg/L as PO4 — (the maximum amount of phosphate received from Detroit, in mg/L as PO4).
I seem to recall that we were assured on our phone call the other day that the changes were
being made to address our concerns, but that the units were in mg/L as P. Since the conversion
factor of P to PO4 is 3, then clearly, the target residual would be about 1-1.3 mg/L as P, but it
looks like the units are PO4 in this permit. They say the max design dosage would be 1.5 mg/L,
which is still a little low, if the units truly are mg/L as P (4.5 mg/L supplement on top of received
water). But I’m really confused by the level they say is received from Detroit, because they very
explicitly say “as PO4” in the engineering report that is the basis for the permit request, not as
I’m thinking some water samples should be taken for alkalinity and orthophosphate (or total P,
given it’s a phosphoric acid product, for convenience of analysis and preservation) and have
your RS laboratory analyze them, so that we can be sure of the phosphate and alkalinity levels.
Sent from my iPhone
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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_b10_223_431_140
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