Mich. Admin. Code R. 325.10308b

Current through Vol. 24-21, December 1, 2024

Section R. 325.10308b - Best available technology

Rule 308b.

(1) The department identifies the following as the best technology, treatment technique, or other means generally available for achieving compliance with the MCL:

(a) For organic contaminants in R 325.10604b, R325.10604d, and R 325.10604g the best available technologies, treatment techniques, or other means available for achieving compliance with the MCLs are granular activated carbon (GAC), packed tower aeration (PTA), or oxidation (OX), as listed in table 1 of this rule.

Table 1 Best available technologies for organic contaminants

Contaminant	GAC	PTA	OX
Alachlor	x
Aldicarb	x
Aldicarb sulfone	x
Aldicarb sulfoxide	x
Atrazine	x
Benzene	x	x
Benzo(a)pyrene	x
Carbofuran	x
Carbon tetrachloride	x	x
Chlordane	x
Dalapon	x
2,4 D	x
Di (2 ethylhexyl)adipate	x	x
Di (2 ethylhexyl)phthalate	x
Dibromochloropropane (DBCP)	x	x
o Dichlorobenzene	x	x
para Dichlorobenzene	x	x
1,2 Dichloroethane	x	x
1,1 Dichloroethylene	x	x
cis 1,2 Dichloroethylene	x	x
trans 1,2 Dichloroethylene	x	x
Dichloromethane	x
1,2 Dichloropropane	x	x
Dinoseb	x
Diquat	x
Endothall	x
Endrin	x
Ethylbenzene	x	x
Ethylene Dibromide (EDB)	x	x
Glyphosate	x
Heptachlor	x
Heptachlor epoxide	x
Hexachlorobenzene	x
Hexachlorocyclopentadiene	x	x
Hexafluoropropylene oxide dimer acid (HFPO-DA)	x1
Lindane	x
Methoxychlor	x
Monochlorobenzene	x	x
Oxamyl (Vydate)	x
Pentachlorophenol	x
Perfluorobutanesulfonic acid (PFBS)	x1
Perfluorohexanesulfonic acid (PFHxS)	x1
Perfluorohexanoic acid (PFHxA)	x1
Perfluorononanoic acid (PFNA)	x1
Perfluorooctanesulfonic acid (PFOS)	x1
Perfluorooctanoic acid (PFOA)	x1
Picloram	x
Polychlorinated biphenyls(PCB)	x
Simazine	x
Styrene	x	x
2,3,7,8 TCDD (Dioxin)	x
Tetrachloroethylene	x	x
Toluene	x	x
Toxaphene	x
2,4,5 TP (Silvex)	x
1,2,4 Trichlorobenzene	x	x
1,1,1 Trichloroethane	x	x
1,1,2 Trichloroethane	x	x
Trichloroethylene	x	x
Vinyl chloride	x
Xylene	x	x

¹Best available technology is GAC or an equally efficient technology.

(b) For inorganic contaminants in R 325.10604c, the best available technologies, treatment techniques, or other means available for achieving compliance with the MCLs are listed in table 2 of this rule. The affordable technology, treatment technique, or other means available to supplies serving 10,000 or fewer people for achieving compliance with the maximum contaminant level for arsenic are listed in table 3 of this rule.

Table 2 Best available technologies for inorganic contaminants

Chemical name	Best available technologies
Antimony	2,7
Arsenic4	1,2, 5,6,7,9,115
Asbestos	2,3,8
Barium	5,6,7,9
Beryllium	1,2,5,6,7
Cadmium	2,5,6,7
Chromium	2,5,62,7
Cyanide	5,7,10
Mercury	21,4,61,7 1
Nickel	5,6,7
Nitrate	5,7,9
Nitrite	5,7
Selenium	1,23,6,7,9
Thallium	1,5

¹Best available technology only if influent Hg concentrations are 10 µg/l or less.

²Best available technology for chromium III only.

³Best available technology for selenium IV only.

⁴BATs for Arsenic V. Pre-oxidation may be required to convert Arsenic III to Arsenic V.

⁵To obtain high removals, iron to arsenic ratio must be at least 20:1.

Key to best available technologies in table:

1 = activated alumina

2 = coagulation/filtration (not BAT for supplies with fewer than 500 service connections)

3 = direct and diatomite filtration

4 = granular activated carbon

5 = ion exchange

6 = lime softening (not BAT for supplies than 500 service connections)

7 = reverse osmosis

8 = corrosion control

9 = electrodialysis

10 = alkaline chlorination (pH greater than or equal to 8.5)

11 = oxidation/filtration

Table 3 Small supplies compliance technologies (SSCTs) for arsenic¹

Small supply compliance technology	Affordable for listed small supply categories.2
Activated alumina (centralized)	All size categories.
Activated alumina (point-of-use)3	All size categories.
Coagulation/filtration	501-3,300, 3,301-10,000.
Coagulation-assisted microfiltration	501-3,300, 3,301-10,000.
Small supply compliance technology	Affordable for listed small supply categories.2
Electrodialysis reversal	501-3,300, 3,301-10,000.
Enhanced coagulation/filtration	All size categories.
Enhanced lime softening (pH more than 10.5)	All size categories.
Ion exchange	All size categories.
Lime softening	501-3,300, 3,301-10,000.
Oxidation/filtration4	All size categories.
Reverse osmosis (centralized)	501-3,300, 3,301-10,000.
Reverse osmosis (point-of-use)3	All size categories.

¹ SSCTs for Arsenic V. Pre-oxidation may be required to convert Arsenic III to Arsenic V.

²Three categories of small supplies are:

(i) those serving 25 or more, but fewer than 501,

(ii) those serving more than 500, but fewer than 3,301, and

(iii) those serving more than 3,300, but fewer than 10,001.

³POU must not be used to obtain a variance.

⁴To obtain high removals, iron to arsenic ratio must be at least 20:1.

(c) For radionuclide contaminants in R 325.10603, the best available technologies, treatment techniques, or other means available for achieving compliance with the MCLs are listed in table 4 for all size supplies. The affordable technology, treatment technique, or other means available for achieving compliance with the maximum contaminant level are listed in table 5 for supplies serving 10,000 or fewer people as categorized in table 6.

Table 4 Best available technologies for radionuclide contaminants

Contaminant	Best available technologies.
Combined radium 226 and radium 228	Ion exchange, reverse osmosis, lime softening.
Uranium	Ion exchange, reverse osmosis, lime softening, coagulation/filtration.
Gross alpha particle activity (excluding radon and uranium)	Reverse osmosis.
Beta particle and proton radioactivity	Ion exchange, reverse osmosis.

Table 5 List of small supplies compliance technologies for radionuclides and limitations to use

Unit Technologies	Limitations (see footnotes)	Operator skill level required *	Raw water quality range and considerations.
1. Ion exchange	(a)	Intermediate	All ground waters.
2. Reverse osmosis (RO)	(b)	Advanced	Surface waters usually require pre-filtration.
3. Lime softening	(c)	Advanced	All waters.
4. Green sand filtration	(d)	Basic
5. Co-precipitation and Barium sulfate	(e)	Intermediate to Advanced	Ground waters with suitable water quality.
6. Electrodialysis/ electrodialysis reversal	Not applicable	Basic to intermediate	All ground waters.
7. Pre-formed hydrous Manganese oxide filtration.	(f)	Intermediate	All ground waters.
8. Activated alumina	(a), (g)	Advanced	All ground waters; competing anion concentrations may affect regeneration frequency.
9. Enhanced coagulation/ filtration	(h)	Advanced	Can treat a wide range of water qualities.

* An operator with a basic skill level has minimal experience in the water treatment field and can perform the necessary system operation and monitoring if provided with proper instruction. The operator is capable of reading and following explicit directions. An operator with an intermediate skill level understands the principles of water treatment and has a knowledge of the regulatory framework. The operator is capable of making system changes in response to source water fluctuations. An operator with an advanced skill level possesses a thorough understanding of the principles of system operation. The operator is knowledgeable in water treatment and regulatory requirements. The operator may, however, have advanced knowledge of only the particular treatment technology. The operator seeks information, remains informed, and reliably interprets and responds to water fluctuations and system intricacies.

Limitations Footnotes: Technologies for Radionuclides:

a. The regeneration solution contains high concentrations of the contaminant ions. Disposal options must be carefully considered before choosing this technology.

b. Reject water disposal options must be carefully considered before choosing this technology.

c. The combination of variable source water quality and the complexity of the water chemistry involved may make this technology too complex for small surface water systems.

d. Removal efficiencies may vary depending on water quality.

e. This technology may be very limited in application to small systems. Since the process requires static mixing, detention basins, and filtration, it is most applicable to systems with sufficiently high sulfate levels that already have a suitable filtration treatment train in place.

f. This technology is most applicable to small systems that already have filtration in place.

g. Handling of chemicals required during regeneration and pH adjustment may be too difficult for small systems without an adequately trained operator.

h. Assumes modification to a coagulation/filtration process already in place.

Table 6 Compliance technologies by supply size category for radionuclide Requirements

Contaminant	Compliance technologies* for supply size categories (population served)
25-500	501-3,300	3,301 - 10,000
1. Combined radium 226 and radium 228	1, 2, 3, 4, 5, 6, 7	1, 2, 3, 4, 5, 6, 7	1, 2, 3, 4, 5, 6, 7
2. Gross alpha particle activity	2	2	2
3. Beta particle activity and photon activity	1, 2	1, 2	1, 2
4. Uranium	1, 8, 9	1, 2, 3, 8, 9	1, 2, 3, 8, 9

* Numbers correspond to those technologies listed in Table 5 of this rule.

(2) The department shall require community water supplies and nontransient, noncommunity water supplies to employ a treatment method identified in subrule (1) of this rule as a condition for granting a variance, except as provided in subrule (3) of this rule. If, after the treatment method is installed in the system, the supply cannot meet the MCL, then the supply is eligible for a variance under this part and section 20 of the act, MCL 325.1020.

(3) If a supply demonstrates through comprehensive engineering assessments, which may include pilot plant studies, that the treatment methods identified in subrule (1) of this rule may only achieve a de minimis reduction in contaminants, then the department may issue a schedule of compliance that requires the supply being granted the variance to examine other treatment methods as a condition of obtaining the variance.

(4) If the department determines that a treatment method identified in subrule (3) of this rule is technically feasible, then the department may require the supply to use that treatment method in connection with a compliance schedule issued under section 20 of the act, MCL 325.1020. The department's determination must be based on studies by the supply and other relevant information.

(5) The department may require a community or noncommunity supply to use point-of-use devices, point-of-entry devices, or other means as a condition of granting a variance or an exemption from the requirements of R 325.10603, R 325.10604b, R 325.10604c, R 325.10604d, or R325.10604g to avoid an unreasonable risk to health. The department may require a public water supply to use point-of-use devices or other means, but not point-of-entry devices, as a condition for granting an exemption from corrosion control treatment requirements for lead and copper in R 325.10604f(2) and (3) to avoid an unreasonable risk to health. The department may require a public water supply to use point-of-entry devices as a condition for granting an exemption from the source water and lead service line replacement requirements for lead and copper under R 325.10604f(4) and (5) to avoid an unreasonable risk to health, provided the supply demonstrates that the device will not cause an increased corrosion of lead and copper bearing materials located between the device and the tap that may increase contaminant levels at the tap.

(6) Community or noncommunity water supplies that use point-of-use or point-of-entry devices under this rule shall meet the conditions in R 325.10313.

Mich. Admin. Code R. 325.10308b

1989 AACS; 1993 AACS; 1994 AACS; 1998 AACS; 2003 AACS; 2005 AACS; 2009 AACS; 2020 MR 14, Eff. 8/3/2020