CODE OF STATE REGULATIONS 1Rebecca McDowell Cook (8/31/97)Secretary of State

Rules of

Department of Natural ResourcesDivision 20�Clean Water Commission

Chapter 10�Underground Storage Tanks�Technical Regulations

Title Page

10 CSR 20-10.010 Interim Prohibition for Deferred Underground Storage Tank Systems .........................................................................3

10 CSR 20-10.011 Interim Prohibition for Deferred UndergroundStorage Tank Systems .........................................................................3

10 CSR 20-10.012 Definitions .......................................................................................3

10 CSR 20-10.020 Performance Standards for New Underground Storage Tank Systems .........................................................................5

10 CSR 20-10.021 Upgrading of Existing Underground Storage Tank Systems.............................6

10 CSR 20-10.022 Notification Requirements.....................................................................7

10 CSR 20-10.030 Spill and Overfill Control....................................................................13

10 CSR 20-10.031 Operation and Maintenance of Corrosion Protection ...................................13

10 CSR 20-10.032 Compatibility ..................................................................................13

10 CSR 20-10.033 Repairs Allowed ...............................................................................13

10 CSR 20-10.034 Reporting and Recordkeeping ...............................................................14

10 CSR 20-10.040 General Requirements for Release Detection forAll Underground Storage Tank Systems..................................................15

10 CSR 20-10.041 Requirements for Petroleum Underground Storage Tank Systems ....................15

10 CSR 20-10.042 Requirements for Hazardous Substance UndergroundStorage Tank Systems........................................................................16

10 CSR 20-10.043 Methods of Release Detection for Tanks ..................................................16

10 CSR 20-10.044 Methods of Release Detection for Piping .................................................18

10 CSR 20-10.045 Release Detection Recordkeeping ..........................................................18

10 CSR 20-10.050 Reporting of Suspected Releases ...........................................................19

10 CSR 20-10.051 Investigation Due to Off-Site Impacts .....................................................19

2 CODE OF STATE REGULATIONS (8/31/97) Rebecca McDowell CookSecretary of State

10 CSR 20-10.052 Release Investigation and Confirmation Steps ...........................................19

10 CSR 20-10.053 Reporting and Cleanup of Spills and Overfills...........................................19

10 CSR 20-10.060 Release Response and Corrective Action..................................................20

10 CSR 20-10.061 Initial Release Response .....................................................................20

10 CSR 20-10.062 Initial Abatement Measures and Site Check..............................................20

10 CSR 20-10.063 Initial Site Characterization .................................................................20

10 CSR 20-10.064 Free-Product Removal ........................................................................21

10 CSR 20-10.065 Investigations for Soil and Groundwater Cleanup .......................................21

10 CSR 20-10.066 Corrective Action Plan .......................................................................21

10 CSR 20-10.067 Public Participation ...........................................................................22

10 CSR 20-10.068 Risk-Based Clean-Up Levels ................................................................22

10 CSR 20-10.070 Temporary Closure............................................................................23

10 CSR 20-10.071 Permanent Closure and Changes in Service ..............................................24

10 CSR 20-10.072 Assessing the Site at Closure or Change in Service.....................................26

10 CSR 20-10.073 Applicability to Previously Closed Underground Storage Tank Systems ............26

10 CSR 20-10.074 Closure Records ...............................................................................26

Title 10�DEPARTMENT OFNATURAL RESOURCES

Division 20�Clean Water CommissionChapter 10�Underground Storage

Tanks�Technical Regulations

10 CSR 20-10.010 Applicability

PURPOSE: This rule defines the under-ground storage tanks that are subject to therequirements of this chapter. This rule con-tains the technical standards for undergroundstorage tanks. This rule is designed specifi-cally to protect the quality of groundwater inthe state as well as to protect human healthand the overall quality of the environment.This rule is promulgated on the authority ofsections 319.100�319.137, RSMo and, asdirected by this law, are based upon federalrules 40 CFR 280.10�40 CFR 280.74.

Editor�s Note: The secretary of state hasdetermined that the publication of this rule inits entirety would be unduly cumbersome orexpensive. The entire text of the material ref-erenced has been filed with the secretary ofstate. This material may be found at theOffice of the Secretary of State or at the head-quarters of the agency and is available to anyinterested person at a cost established bylaw.

(1) The requirements of this chapter apply toall owners and operators of an undergroundstorage tank (UST) system as defined in 10CSR 20-10.012, except as otherwise provid-ed in sections (2)�(4) of this rule. Any USTsystem listed in section (3) of this rule mustmeet the requirements of 10 CSR 20-10.011.

(2) The following UST systems are excludedfrom the requirements of this chapter:

(A) Any UST system holding hazardouswastes listed or identified in the MissouriHazardous Waste Management Law, sections260.350�260.434, RSMo and the rules pro-mulgated thereunder or a mixture of haz-ardous waste and other regulated substances,except for waste oil as defined in 10 CSR25-11.279;

(B) Any wastewater treatment tank systemthat is part of a wastewater treatment facilityregulated under Section 402 or 307(b) of theClean Water Act (33 U.S.C.A. 1251);

(C) Equipment or machinery that containsregulated substances for operational purposessuch as hydraulic lift tanks and electricalequipment tanks;

(D) Any UST system whose capacity isone hundred ten (110) gallons or less;

(E) Any UST system that contains a deminimis concentration of regulated sub-

stances; and (F) Any emergency spill or overflow con-

tainment UST system that is expeditiouslyemptied after use.

(3) Deferrals. Rules 10 CSR 20-10.020�10CSR 20-10.053 and closure requirements in10 CSR 20-10.070�10 CSR 20-10.074 donot apply to any of the following types ofUST systems:

(A) Wastewater treatment tank systems; (B) Any UST systems containing radioac-

tive material that are regulated under theAtomic Energy Act of 1954 (42 U.S.C. 2011and following);

(C) Any UST system that is part of anemergency generator system at nuclear powergeneration facilities regulated by the NuclearRegulatory Commission under 10 CFR 50Appendix A;

(D) Airport hydrant fuel distribution sys-tems; and

(E) UST systems with field-constructedtanks.

(4) Deferrals. The release detection require-ments of rules 10 CSR 20-10.040�10 CSR20-10.045 do not apply to any UST systemsthat store fuel solely for use by emergencypower generators.

AUTHORITY: sections 319.100, 319.105,319.107, 319.111 and 319.114, RSMo (1994)and 319.109, 319.132 and 319.137, RSMo(Supp. 1995).* Original rule filed April 2,1990, effective Sept. 28, 1990. Amended:Filed Jan. 2, 1996, effective Aug. 30, 1996.

*Original authority: 319.100, RSMo (1989), amended1991, 1993; 319.105, RSMo (1989); 319.107, RSMo(1989), amended 1994; 319.109, RSMo (1989), amended1995; 319.111, RSMo (1989); 319.114, RSMo (1989);319.132, RSMo (1991), amended 1995; 319.137, RSMo(1989), amended 1993, 1995.

10 CSR 20-10.011 Interim Prohibition forDeferred Underground Storage Tank Sys-tems

PURPOSE: This rule establishes minimumperformance standards for the installation ofdeferred underground storage tanks.

Editor�s Note: The secretary of state hasdetermined that the publication of this rule inits entirety would be unduly cumbersome orexpensive. The entire text of the material ref-erenced has been filed with the secretary ofstate. This material may be found at theOffice of the Secretary of State or at the head-quarters of the agency and is available to anyinterested person at a cost established bystate law.

(1) No person may install an undergroundstorage tank (UST) system listed in 10 CSR20-10.010(3) for the purpose of storing regu-lated substances unless the UST system(whether of single- or double-wall construc-tion)�

(A) Will prevent releases due to corrosionor structural failure for the operational life ofthe UST system;

(B) Is cathodically protected against corro-sion, constructed of noncorrodible material,steel-clad with a noncorrodible material ordesigned in a manner to prevent the release orthreatened release of any stored substance;and

(C) Is constructed or lined with materialthat is compatible with the stored substance.

(2) Notwithstanding section (1) of this rule, aUST system without corrosion protectionmay be installed at a site that is determinedby a corrosion expert not to be corrosiveenough to cause it to have a release due tocorrosion during its operating life. Ownersand operators must maintain records thatdemonstrate compliance with the require-ments of this section for the remaining life ofthe tank.

(3) The determination in section (2) of thisrule should comply with the following rec-ommended practice: The National Asso-ciation of Corrosion Engineers StandardRP-02-85, Control of External Corrosion onMetallic Buried, Partially Buried, or Sub-merged Liquid Storage Systems.

AUTHORITY: sections 319.105, RSMo (Cum.Supp. 1989) and 644.041, RSMo (1986).*Original rule filed April 2, 1990, effectiveSept. 28, 1990.

*Original authority: 319.105, RSMo (1989) and 644.041,RSMo (1972), amended 1973.

10 CSR 20-10.012 Definitions

PURPOSE: This rule defines specific wordsused in this chapter.

PUBLISHER�S NOTE: The publication of thefull text of the material that the adoptingagency has incorporated by reference in thisrule would be unduly cumbersome or expen-sive. Therefore, the full text of that materialwill be made available to any interested per-son at both the Office of the Secretary of Stateand the office of the adopting agency, pur-suant to section 536.031.4, RSMo. Suchmaterial will be provided at the cost estab-lished by state law.

CODE OF STATE REGULATIONS 3Rebecca McDowell Cook (8/31/97)Secretary of State

Chapter 10—Underground Storage Tanks—Technical Regulations 10 CSR 20-10

(1) Many definitions relevant to this rule areset forth in the underground storage tank lawin section 319.100, RSMo. The definitionsset forth in 40 CFR 280.12, July 1, 1994, areincorporated by reference, subject to the fol-lowing additions, modifications, substitutionsor deletions in the subsections:

(A) Definitions beginning with the letterA.

1. �Airline company� means any per-son, firm, partnership, corporation, trustee,receiver or assignee, and all other persons,whether or not in a representative capacity,undertaking to engage in the carriage of per-sons or cargo for hire by commercial aircraftpursuant to certificates of convenience andnecessity issued by the federal Civil Aero-nautics Board, or successor thereof, or anynoncertified air carrier authorized to engagein irregular and infrequent air transportationby the federal Civil Aeronautics Board, orsuccessor thereof;

(B) Definitions beginning with the letter B.(Reserved);

(C) Definitions beginning with the letterC.

1. To the definition of �CERCLA� at 40CFR 280.12, incorporated in this rule, addthe words �by the Superfund Amendmentsand Reauthorization Act of 1986� after thewords �as amended�;

(D) Definitions beginning with the letterD.

1. �De minimus� means�A. Any volume of regulated sub-

stance(s) contained in a tank with a capacityof less than one hundred ten (110) gallons; or

B. A very low concentration of regu-lated substances; or

C. Any volume of regulated sub-stance(s) contained in an emergency backuptank that holds regulated substances for onlya short period of time and is expeditiouslyemptied after use. (Comment: De minimustanks include: swimming pools, permittedwastewater treatment facilities and chlorinat-ed, potable water storage tanks. An oil-waterseparator is not a de minimus system unlessthe tank has a less than one hundred ten (110)gallon capacity.)

2. �Department,� unless otherwise stated,means the Missouri Department of NaturalResources;

(E) Definitions beginning with the letter E.1. In the definition for �existing tank

system� in 40 CFR 280.12 incorporated inthis rule, substitute the date �September 28,1990� for the date �December 22, 1988�;

(F) Definitions beginning with the letter F.(Reserved);

(G) Definitions beginning with the letterG. (Reserved);

(H) Definitions beginning with the letterH.

1. This definition shall apply in lieu ofthe definition of �hazardous substance USTsystem� in 40 CFR 280.12 incorporated inthis rule. �Hazardous substance UST system�means a UST system that contains a haz-ardous substance defined in Section 101(14)of the CERCLA (but not including any sub-stance regulated as a hazardous waste underthe Missouri Hazardous Waste ManagementLaw, sections 260.350�260.434, RSMo) orany mixture of these substances andpetroleum, and which is not a petroleum USTsystem;

(I) Definitions beginning with the letter I.1. The definition for �implementing

agency� in 40 CFR 280.12 is not incorporat-ed into this rule.

2. The terms �in-operation,� �in-ser-vice,� and �in-use� are equivalent and meaninput or output that occurs on a regular basisfor the tank�s intended purpose. In determin-ing the status of a tank, the department mayconsider factors including, but not limited to:routine input or outputs from the tank and theactivity status of tank-related operations atthe premises where the tank is located. Atank is considered to be in-operation, in-ser-vice, and in-use beginning with the first inputof a regulated substance into the tank system;

(J) Definitions beginning with the letter J.(Reserved);

(K) Definitions beginning with the letterK. (Reserved);

(L) Definitions beginning with the letter L.(Reserved);

(M) Definitions beginning with the letterM. (Reserved);

(N) Definitions beginning with the letterN.

1. In the definition for �new tank sys-tem� in 40 CFR 280.12 incorporated in thisrule, substitute the date �September 28,1990� for the date �December 22, 1988�;

(O) Definitions beginning with the letterO.

1. In the definition for �operational life�in 40 CFR 280.12 incorporated in this rule,substitute �10 CSR 20-10.070�10 CSR 20-10.074� for �Subpart G.�

2. The term �out-of-operation,� �out-of-service,� and �out-of-use� are equivalentand mean input or output activity no longeroccurs on a regular basis for the tank�sintended purpose.

3. The definition for �owner� in 40CFR 280.12, is not incorporated in this ruleand the definition in section 319.100(6),RSMo, shall be used instead;

(P) Definitions beginning with the letter P.

1. The definition for �person� in 40CFR 280.12 is not incorporated in this ruleand the definition in section 319.100(8),RSMo, shall be used instead;

(Q) Definitions beginning with the letterQ. (Reserved);

(R) Definitions beginning with the letter R.1. �Railroad corporation� means all

corporations, companies or individuals nowowning or operating, or which may hereafterown or operate, any railroad in this state.

2. The definition for �regulated sub-stance� in 40 CFR 280.12 is not incorporat-ed in this rule, and the definition in section319.100(9), RSMo, shall be used instead.

3. The definition for �release� in 40CFR 280.12 is not incorporated in this rule,and the definition in section 319.100(10),RSMo, shall be used instead;

(S) Definitions beginning with the letter S.1. In lieu of the definition for �septic

tank� in 40 CFR 280.12, the definition for�septic tank� shall be any watertight, coveredreceptacle designed and constructed toreceive the discharge of sewage, separatesolids from liquid, digest organic matter,store liquids through a period of detentionand allow the clarified liquids to discharge toa soil treatment system;

(T) Definitions beginning with the letter T.(Reserved);

(U) Definitions beginning with the letterU.

1. In the definition of �upgrade� in 40CFR 280.12 incorporated in this rule, substi-tute the words �regulated substance� for theword �product.�

2. The definition for �underground stor-age tank� or �UST� found in 40 CFR 280.12is not incorporated in this rule, and the defi-nition in section 319.100(11), RSMo, shallbe used instead;

(V) Definitions beginning with the letter V.(Reserved);

(W) Definitions beginning with the letterW. (Reserved);

(X) Definitions beginning with the letterX. (Reserved);

(Y) Definitions beginning with the letter Y.(Reserved);

(Z) Definitions beginning with the letter Z.(Reserved).

AUTHORITY: sections 319.100, 319.105,319.107, 319.111 and 319.114, RSMo (1994)and 319.109, 319.132 and 319.137, RSMo(Cum. Supp. 1996).* Original rule filed April2, 1990, effective Sept. 28, 1990. Amended:Filed Dec. 31, 1991, effective Aug. 6, 1992.Amended: Filed Jan. 2, 1996, effective Aug.30, 1996. Amended: Filed Jan. 14, 1997,effective Sept. 30, 1997.

4 CODE OF STATE REGULATIONS (8/31/97) Rebecca McDowell CookSecretary of State

10 CSR 20-10—NATURAL RESOURCES Division 20—Clean Water Commission

*Original authority: 319.100, RSMo (1989), amended1991, 1993; 319.105, RSMo (1989); 319.107, RSMo(1986), amended 1994; 319.109, RSMo (1989), amended1995; 319.111, RSMo (1989); 319.114, RSMo (1989);319.132, RSMo (1991); amended 1995; and 319.137,RSMo (1989), amended 1993, 1995.

10 CSR 20-10.020 Performance Standardsfor New Underground Storage Tank Sys-tems

PURPOSE: This rule sets the standards fortanks, piping, spill and overfill preventionequipment, installation and certification ofinstallation that new underground storagetanks must meet.

Editor�s Note: The secretary of state hasdetermined that the publication of this rule inits entirety would be unduly cumbersome orexpensive. The entire text of the rule has beenfiled with the secretary of state. The entiretext of the rule may be found at the head-quarters of the agency and is available to anyinterested person at a cost established bystate law. The form mentioned in this rule fol-lows 10 CSR 20-10.022.

(1) In order to prevent releases due to struc-tural failure, corrosion or spills and overfillsfor as long as the underground storage tank(UST) system is used to store regulated sub-stances, all owners and operators of new USTsystems must meet the following require-ments:

(A) Tanks. Each tank must be properlydesigned and constructed, and any portionunderground that routinely contains productmust be protected from corrosion, in accor-dance with a code of practice developed by anationally-recognized association or indepen-dent testing laboratory as follows:

1. The tank is constructed of fiber-glass-reinforced plastic and complies withone (1) or more of the following industrycodes:

A. Underwriters� Laboratories Stan-dard 1316, Standard for Glass- Fiber-Rein-forced Plastic Underground Storage Tanks forPetroleum Products; or

B. American Society of Testing andMaterials Standard D4021-86, StandardSpecification for Glass-Fiber-ReinforcedPolyester Underground Petroleum StorageTanks; or

2. The tank is constructed of steel andcathodically protected in the following man-ner:

A. The tank is coated with a suitabledielectric material;

B. Field-installed cathodic protectionsystems are designed by a corrosion expert;

C. Impressed current systems aredesigned to allow determination of currentoperating status as required in 10 CSR20-10.031(1)(C);

D. Cathodic protection systems areoperated and maintained in accordance with10 CSR 20-10.031 or according to guidelinesestablished by the department; and

E. The following codes and standardsmay be used to comply with paragraph(1)(A)2. of this rule:

(I) Steel Tank Institute Specifica-tion for STI-P3 System of External CorrosionProtection of Underground Steel StorageTanks:

(II) Underwriters� LaboratoriesStandard 1746, Corrosion Protection Systemsfor Underground Storage Tanks;

(III) National Association of Corro-sion Engineers Standard RP-02-85, Controlof External Corrosion on Metallic Buried,Partially Buried or Submerged Liquid StorageSystems;

(IV) Underwriters� LaboratoriesStandard 58, Standard for Steel UndergroundTanks for Flammable and Combustible Liq-uids;

3. The tank is constructed of a steel,fiberglass-reinforced plastic composite thatcomplies with one (1) of the following indus-try codes:

A. Underwriters� Laboratories Stan-dard 1746, Corrosion Protection Systems forUnderground Storage Tanks; or

B. The Association for CompositeTanks ACT-100, Specification for the Fabri-cation of FRP Clad Underground StorageTanks;

4. The tank is constructed of metal with-out additional corrosion protection measuresprovided that�

A. The tank is installed at a site thatis determined by a corrosion expert not to becorrosive enough to cause it to have a releasedue to corrosion during its operating life; and

B. Owners and operators maintainrecords that demonstrate compliance with therequirements of subparagraph (1)(B)4.A. ofthis rule for the remaining life of the tank; or

5. The tank construction and corrosionprotection are determined by the departmentto be designed to prevent the release orthreatened release of any stored regulatedsubstance in a manner that is no less protec-tive of human health and the environmentthan paragraphs (1)(A)1.�4. of this rule;

(B) Piping. The piping that routinely con-tains regulated substances and is in contactwith the ground must be properly designed,constructed and protected from corrosion inaccordance with a code of practice developed

by a nationally recognized association orindependent testing laboratory as follows:

1. The piping is constructed of fiber-glass-reinforced plastic;

2. The following codes and standardsmay be used to comply with paragraph(1)(B)1. of this rule:

A. Underwriters� Laboratories Sub-ject 971, UL Listed Non-Metal Pipe; and

B. Underwriters� Laboratories Stan-dard 567, Pipe Connectors for Flammableand Combustible and LP Gas;

3. The piping is constructed of steel andcathodically protected in the following man-ner:

A. The piping is coated with a suit-able dielectric material;

B. Field-installed cathodic protectionsystems are designed by a corrosion expert;

C. Impressed current systems aredesigned to allow determination of currentoperating status as required in 10 CSR20-10.031(1)(C);

D. Cathodic protection systems areoperated and maintained in accordance with10 CSR 20-10.031; and

E. The following codes and standardsmay be used to comply with paragraph(1)(B)3. of this rule:

(I) National Fire Protection Associ-ation Standard 30, Flammable and Com-bustible Liquids Code;

(II) American Petroleum InstitutePublication 1615, Installation of Under-ground Petroleum Storage Systems;

(III) American Petroleum InstitutePublication 1632, Cathodic Protection ofUnderground Petroleum Storage Tanks andPiping Systems; and

(IV) National Association of Cor-rosion Engineers Standard RP-01-69, Controlof External Corrosion on Submerged MetallicPiping Systems;

4. The piping is constructed of metalwithout additional corrosion protection mea-sures provided that�

A. The piping is installed at a site thatis determined by a corrosion expert to not becorrosive enough to cause it to have a releasedue to corrosion during its operating life; and

B. Owners and operators maintainrecords that demonstrate compliance with therequirements of subparagraph (1)(A)4.A. ofthis rule for the remaining life of the tank;

5. The following codes may be used tocomply with paragraph (1)(B)4. of this rule:

A. National Fire Protection Associa-tion Standard 30, Flammable and Com-bustible Liquids Code; and

B. National Association of CorrosionEngineers Standard RP-01-69, Control of

CODE OF STATE REGULATIONS 5Rebecca McDowell Cook (8/31/97)Secretary of State

Chapter 10—Underground Storage Tanks—Technical Regulations 10 CSR 20-10

External Corrosion on Submerged MetallicPiping Systems; or

6. The piping construction and corro-sion protection are determined by the depart-ment to be designed to prevent the release orthreatened release of any stored regulatedsubstance in a manner that is no less protec-tive of human health and the environmentthan the requirements in paragraphs(1)(B)1.�5. of this rule;

(C) Spill and Overfill Prevention Equip-ment.

1. Except as provided in paragraph(1)(C)2. of this rule, to prevent spilling andoverfilling associated with product transfer tothe UST system, owners and operators mustuse the following spill and overfill preventionequipment:

A. Spill prevention equipment thatwill prevent release of product to the envi-ronment when the transfer hose is detachedfrom the fill pipe (for example, a spill catch-ment basin); and

B. Overfill prevention equipment thatwill�

(I) Automatically shut off flow intothe tank when the tank is no more than nine-ty-five percent (95%) full;

(II) Alert the transfer operatorwhen the tank is no more than ninety percent(90%) full by restricting the flow into thetank or triggering a high-level alarm; or

(III) Restrict flow thirty (30) min-utes prior to overfilling, alert the operatorwith a high level alarm one (1) minute beforeoverfilling or automatically shut off flow intothe tank so that none of the fittings located ontop of the tank are exposed to product due tooverfilling.

2. Owners and operators are notrequired to use the spill and overfill preven-tion equipment specified in paragraph(1)(C)1. of this rule if�

A. Alternative equipment is used thatis determined by the department to be no lessprotective of human health and the environ-ment than the equipment specified in sub-paragraph (1)(C)1.A. or B. of this rule; or

B. The UST system is filled by trans-fers of no more than twenty-five (25) gallonsat one time;

(D) Installation. All tanks and piping mustbe properly installed in accordance with acode of practice developed by a nationallyrecognized association or independent testinglaboratory and in accordance with the manu-facturer�s instructions. Tank and piping sys-tem installation practices and proceduresdescribed in the following codes may be usedto comply with the requirements of subsec-tion (1)(D) of this rule:

1. American Petroleum Institute Publi-cation 1615, Installation of UndergroundPetroleum Storage System; or

2. Petroleum Equipment Institute Publi-cation RP100, Recommended Practices forInstallation of Underground Liquid StorageSystems; and

(E) Certification of Installation. All ownersand operators must ensure that one (1) ormore of the following methods of certifica-tion, testing or inspection is used to demon-strate compliance with subsection (1)(D) ofthis rule by providing a certification of com-pliance on the UST notification form inaccordance with 10 CSR 20-10.022:

1. The installer has been certified by thetank and piping manufacturers;

2. The installer has been certified orlicensed by the department;

3. The installation has been inspectedand certified by a registered professionalengineer with education and experience inUST system installation;

4. The installation has been inspectedand approved by the department;

5. All work listed in the manufacturer�sinstallation checklists has been completed; or

6. The owner and operator have com-plied with another method for ensuring com-pliance with subsection (1)(D) of this rulethat is determined by the department to be noless protective of human health and the envi-ronment.

AUTHORITY: sections 319.105, RSMo (Cum.Supp. 1989) and 644.041, RSMo (1986).*Original rule filed April 2, 1990, effectiveSept. 28, 1990.

*Original authority: 319.105, RSMo (1989) and 644.041,RSMo (1972), amended 1973.

10 CSR 20-10.021 Upgrading of ExistingUnderground Storage Tank Systems

PURPOSE: This rule contains the options forupgrading existing underground storage tanksfor continued operation after December 22,1998.

Editor�s Note: The secretary of state hasdetermined that the publication of this rule inits entirety would be unduly cumbersome orexpensive. The entire text of the material ref-erenced has been filed with the secretary ofstate. This material may be found at theOffice of the Secretary of State or at the head-quarters of the agency and is available to anyinterested person at a cost established bystate law.

(1) Alternatives Allowed. No later thanDecember 22, 1998, all existing undergroundstorage tank (UST) systems must complywith one (1) of the following requirements:

(A) New UST system performance stan-dards in 10 CSR 20-10.020;

(B) The upgrading requirements in sec-tions (2)�(4) of this rule; or

(C) Closure requirements in 10 CSR20-10.070�10 CSR 20-10.074, includingapplicable requirements for corrective actionin 10 CSR 20-10.060�10 CSR 20-10.067.

(2) Tank Upgrading Requirements. Steeltanks must be upgraded to meet one (1) of thefollowing requirements in accordance with acode of practice developed by a nationally-recognized association or independent testinglaboratory:

(A) Interior Lining. A tank may be upgrad-ed by internal lining if�

1. The lining is installed in accordancewith the requirements of 10 CSR 20-10.033;and

2. Within ten (10) years after lining, andevery five (5) years after that, the lined tankis internally inspected and found to be struc-turally sound with the lining still performingin accordance with original design specifica-tions;

(B) Cathodic Protection. A tank may beupgraded by cathodic protection if thecathodic protection system meets the require-ments of the performance standards for newUST systems in 10 CSR 20-10.020(1)(A)2.B.�D. and the integrity of the tank isensured using one (1) of the following meth-ods:

1. The tank is internally inspected andassessed to ensure that the tank is structural-ly sound and free of corrosion holes prior toinstalling the cathodic protection system;

2. The tank has been installed for lessthan ten (10) years and is monitored monthlyfor releases in accordance with release detec-tion methods 10 CSR 20-10.043(1)(D)�(H);

3. The tank has been installed for lessthan ten (10) years and is assessed for corro-sion holes by conducting two (2) tightnesstests that meet the requirements of releasedetection method 10 CSR 20-10.043(1)(C).The first tightness test must be conducted pri-or to installing the cathodic protection sys-tem. The second tightness test must be con-ducted between three and six (3�6) monthsfollowing the first operation of the cathodicprotection system; or

4. The tank is assessed for corrosionholes by a method that is determined by thedepartment to prevent releases in a mannerthat is no less protective of human health andthe environment than paragraphs (2)(B)1.�3.of this rule; and

6 CODE OF STATE REGULATIONS (8/31/97) Rebecca McDowell CookSecretary of State

10 CSR 20-10—NATURAL RESOURCES Division 20—Clean Water Commission

(C) Internal Lining Combined WithCathodic Protection. A tank may be upgrad-ed by both internal lining and cathodic pro-tection if�

1. The lining is installed in accordancewith the requirements of 10 CSR 20-10.033;and

2. The cathodic protection system meetsthe requirements of 10 CSR 20-10.020(1)(A)2.B.�D.

(3) Piping Upgrading Requirements. Metalpiping that routinely contains regulated sub-stances and is in contact with the groundmust be cathodically protected in accordancewith a code of practice developed by a nation-ally recognized association or independenttesting laboratory and must meet the require-ments of 10 CSR 20-10.020(1)(B)3.B.�D.

(4) Spill and Overfill Prevention Equipment.To prevent spilling and overfilling associatedwith product transfer to the UST system, allexisting UST systems must comply with newUST system spill and overfill preventionequipment requirements specified in 10 CSR20-10.020(1)(C).

(5) The following codes and standards may beused to comply with this rule:

(A) American Petroleum Institute Publica-tion 1631, Recommended Practice for theInterior Lining of Existing Steel UndergroundStorage Tanks;

(B) National Association of CorrosionEngineers Standard RP-02-85, Control ofExternal Corrosion on Metallic Buried, Par-tially Buried, or Submerged Liquid StorageSystems; and

(C) American Petroleum Institute Publica-tion 1632, Cathodic Protection of Under-ground Petroleum Storage Tanks and PipingSystems.

AUTHORITY: sections 319.105, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990.

*Original authority: 319.105, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.022 Notification Require-ments

PURPOSE: This rule specifies the registra-tion procedures for underground storagetanks.

PUBLISHER�S NOTE: The publication of thefull text of the material that the adoptingagency has incorporated by reference in thisrule would be unduly cumbersome or expen-

sive. Therefore, the full text of that materialwill be made available to any interested per-son at both the Office of the Secretary of Stateand the office of the adopting agency, pur-suant to section 536.031.4, RSMo. Suchmaterial will be provided at the cost estab-lished by state law.

(1) Any owner who intends to install anunderground storage tank (UST) system afterOctober 28, 1990, must, at least thirty (30)days before installing the tank, notify thedepartment by letter of the intent to install aUST. The letter must provide the owner�sname, the name and location of the facilitywhere the UST will be installed, the date thatthe installation is expected to commence andthe date that the tank is expected to bebrought in-use.

(2) Any owner who brings a UST system in-use after September 28, 1990, must, withinthirty (30) days of bringing the tank in-use,register the completed UST system on formsprovided by the department. Note: Ownersand operators of UST systems that were in theground on or after May 8, 1986, unless tak-en out-of-operation on or before January 1,1974, were required to notify the state inaccordance with the Hazardous and SolidWaste Amendments of 1984, P.L. 98-616, ona form published by Environmental Protec-tion Agency (EPA) on November 8, 1985 (50FR 46602), unless notice was given pursuantto section 103(c) of Comprehensive Environ-mental Response, Compensation, and Liabil-ity Act of 1980 (CERCLA). Owners andoperators who have not complied with thenotification requirements may use forms pro-vided by the department.

(3) Notices required to be submitted undersection (2) of this rule must provide all of theinformation requested in the form providedby the department for each UST.

(4) All owners and operators of new UST sys-tems must certify in the notification formcompliance with the following requirements:

(A) Installation of tanks and piping in 10CSR 20-10.020(1)(E);

(B) Cathodic protection of steel tanks andpiping under 10 CSR 20-10.020(1)(A) and(B);

(C) Financial responsibility in 10 CSR20-10.090 through 10 CSR 20-10.112; and

(D) Release detection in 10 CSR 20-10.041and 10 CSR 20-10.042.

(5) An owner/operator shall complete and filean updated registration form if the ownerinformation or information regarding tankequipment and operation, as reported on the

current registration with the department,changes.

(6) All owners and operators of new UST sys-tems must ensure that the installer certifies inthe notification form that the methods used toinstall the tanks and piping comply with therequirements in 10 CSR 20-10.020(1)(D).

(7) The department shall issue a Certificate ofRegistration for any tanks which meet therequirements in sections (1) through (5) ofthis rule and 10 CSR 20-10.020 and 10 CSR20-10.021. The Certificate of Registrationshall be valid for five (5) years except asdescribed in section (8) of this rule.

(8) The department shall establish effectivedates and expiration dates for Certificates ofRegistration issued under this rule. Thesedates shall establish a period of from one tofive (1�5) years for an initial Certificate ofRegistration and a period of five (5) years forsubsequent Certificates of Registration.

(9) Information submitted to the departmentafter January 1, 1990, under sections (1)through (6) of this rule for a tank brought intouse before January 1, 1990, or for a tankbrought into use after September 28, 1990, isan application for a Certificate of Registra-tion and shall be accompanied by a fee asdescribed in section (10), except as describedin section (11).

(10) Fees required under section (9) of thisrule shall be paid in one (1) payment of sev-enty-five dollars ($75). No fees shall be col-lected for registration of tanks which werepermanently closed prior to August 28, 1989.No further fees shall be assessed upon regis-tered USTs once permanent closure has beencompleted and any fees to date have beenpaid.

(11) The department may waive part of thethirty (30)-day prior notice required in sec-tion (1) for reasons including, but not limitedto, weather, contractual arrangements,department inspection scheduling and avail-ability of tank service vendors. A request fora waiver must accompany the informationrequired under section (1) of this rule.

AUTHORITY: sections 319.103 and 319.123,RSMo (1994) and 319.137, RSMo (Cum.Supp. 1996).* Original rule filed April 2,1990, effective Sept. 28, 1990. Amended:Filed June 1, 1995, effective Jan. 30, 1996.Amended: Filed Jan. 2, 1996, effective Aug.30, 1996. Amended: Filed Jan. 14, 1997,effective Sept. 30, 1997.

CODE OF STATE REGULATIONS 7Rebecca McDowell Cook (8/31/97)Secretary of State

Chapter 10—Underground Storage Tanks—Technical Regulations 10 CSR 20-10

*Original authority: 319.103, RSMo (1989); 319.123,RSMo (1989); 319.137, RSMo (1989), amended 1993,1995.

8 CODE OF STATE REGULATIONS (8/31/97) Rebecca McDowell CookSecretary of State

10 CSR 20-10—NATURAL RESOURCES Division 20—Clean Water Commission

10 CSR 20-10.030 Spill and Overfill Con-trol

PURPOSE: This rule is designed to preventreleases during routine filling of the under-ground storage tank with product.

Editor�s Note: The secretary of state hasdetermined that the publication of this rule inits entirety would be unduly cumbersome orexpensive. The entire text of the material ref-erenced has been filed with the secretary ofstate. This material may be found at theOffice of the Secretary of State or at the head-quarters of the agency and is available to anyinterested person at a cost established bystate law.

(1) Owners and operators must ensure thatreleases due to spilling or overfilling do notoccur. The owner and operator must ensurethat the volume available in the tank is greaterthan the volume of product to be transferredto the tank before the transfer is made andthat the transfer operation is monitored con-stantly to prevent overfilling and spilling.

(2) The owner and operator must report,investigate and cleanup any spills and over-fills in accordance with 10 CSR 20-10.053.

(3) Guidance on spill and overfill preventionappears in the�

(A) American Petroleum Institute Publica-tion 1621, Recommended Practice for BulkLiquid Stock Control at Retail Outlets; and

(B) National Fire Protection AssociationStandard 30, Flammable and CombustibleLiquids Code.

AUTHORITY: sections 319.105, RSMo (Cum.Supp. 1989) and 644.041, RSMo (1986).*Original rule filed April 2, 1990, effectiveSept. 28, 1990.

*Original authority: 319.105, RSMo (1989) and 644.041,RSMo (1972), amended 1973.

10 CSR 20-10.031 Operation and Mainte-nance of Corrosion Protection

PURPOSE: This rule contains the require-ments for corrosion protection systems.

Editor�s Note: The secretary of state hasdetermined that the publication of this rule inits entirety would be unduly cumbersome orexpensive. The entire text of the material ref-erenced has been filed with the secretary ofstate. This material may be found at theOffice of the Secretary of State or at the head-quarters of the agency and is available to any

interested person at a cost established bystate law.

(1) All owners and operators of steel under-ground storage tank (UST) systems with cor-rosion protection must comply with the fol-lowing requirements to ensure that releasesdue to corrosion are prevented for as long asthe UST system is used to store regulatedsubstances.

(A) All corrosion protection systems mustbe operated and maintained to continuouslyprovide corrosion protection to the metalcomponents of that portion of the tank andpiping that routinely contain regulated sub-stances and are in contact with the ground.

(B) All UST systems equipped withcathodic protection systems must be inspect-ed for proper operation by a qualified cathod-ic protection tester in accordance with thefollowing requirements:

1. Frequency. All cathodic protectionsystems must be tested within six (6) monthsof installation and at least every three (3)years after that or according to another rea-sonable time frame established by the depart-ment; and

2. Inspection criteria. The criteria thatare used to determine that cathodic protectionis adequate as required by this section mustbe in accordance with a code of practicedeveloped by a nationally recognized associa-tion listed in section (2) of this rule.

(C) UST systems with impressed currentcathodic protection systems must also beinspected every sixty (60) days to ensure theequipment is running properly; and

(D) For UST systems using cathodic pro-tection, records of the operation of thecathodic protection must be maintained (inaccordance with 10 CSR 20-10.034) todemonstrate compliance with the perfor-mance standards in this rule. These recordsmust provide the following:

1. The results of the last three (3)inspections required in subsection (1)(C) ofthis rule; and

2. The results of testing from the lasttwo (2) inspections required in subsection(1)(B) of this rule.

(2) National Association of Corrosion Engi-neers Standard RP-02-85, Control of Exter-nal Corrosion on Metallic Buried, PartiallyBuried, or Submerged Liquid Storage Sys-tems, may be used to comply with paragraph(1)(B)2. of this rule.

AUTHORITY: sections 319.105, RSMo (Cum.Supp. 1989) and 644.041, RSMo (1986).*Original rule filed April 2, 1990, effectiveSept. 28, 1990.

*Original authority: 319.105, RSMo (1989) and 644.041,RSMo (1972), amended 1973.

10 CSR 20-10.032 Compatibility

PURPOSE: This rule prevents releasescaused by chemical action on the under-ground storage tank system by the storedproduct.

Editor�s Note: The secretary of state hasdetermined that the publication of this rule inits entirety would be unduly cumbersome orexpensive. The entire text of the material ref-erenced has been filed with the secretary ofstate. This material may be found at theOffice of the Secretary of State or at the head-quarters of the agency and is available to anyinterested person at a cost established bystate law.

(1) Owners and operators must use an under-ground storage tank (UST) system made of orlined with materials that are compatible withthe substance stored in the UST system.

(2) Owners and operators storing alcoholblends may use the following codes to com-ply with the requirements of this section:

(A) American Petroleum Institute Publica-tion 1626, Storing and Handling Ethanol andGasoline-Ethanol Blends at Distribution Ter-minals and Service Stations; and

(B) American Petroleum Institute Publica-tion 1627, Storage and Handling of Gasoline-Methanol/Cosolvent Blends at DistributionTerminals and Service Stations.

AUTHORITY: sections 319.105, RSMo (Cum.Supp. 1989) and 644.041, RSMo (1986).*Original rule filed April 2, 1990, effectiveSept. 28, 1990.

*Original authority: 319.105, RSMo (1989) and 644.041,RSMo (1972), amended 1973.

10 CSR 20-10.033 Repairs Allowed

PURPOSE: This rule describes methods forrepair of underground storage tank systems.

Editor�s Note: The secretary of state hasdetermined that the publication of this rule inits entirety would be unduly cumbersome orexpensive. The entire text of the material ref-erenced has been filed with the secretary ofstate. This material may be found at theOffice of the Secretary of State or at the head-quarters of the agency and is available to anyinterested person at a cost established bystate law.

CODE OF STATE REGULATIONS 13Rebecca McDowell Cook (8/31/97)Secretary of State

Chapter 10—Underground Storage Tanks—Technical Regulations 10 CSR 20-10

(1) Owners and operators of undergroundstorage tank (UST) systems must ensure thatrepairs will prevent releases due to structuralfailure or corrosion as long as the UST sys-tem is used to store regulated substances.

(2) The repairs must meet the followingrequirements:

(A) Repairs to UST systems must be prop-erly conducted in accordance with a code ofpractice developed by a nationally recognizedassociation or an independent testing labora-tory.

1. The following codes and standardsmay be used to comply with subsection(2)(A) of this rule:

A. National Fire Protection Associa-tion Standard 30, Flammable and Com-bustible Liquids Code;

B. American Petroleum InstitutePublication 2200, Repairing Crude Oil, Liq-uefied Petroleum Gas, and Product Pipelines;

C. American Petroleum InstitutePublication 1631, Recommended Practice forthe Interior Lining of Existing Steel Under-ground Storage Tanks; and

D. National Leak Prevention Associ-ation Standard 631, Spill Prevention, Mini-mum 10-Year Life Extension of Existing SteelUnderground Tanks by Lining Without theAddition of Cathodic Protection;

(B) Repairs to fiberglass-reinforced plastictanks may be made by the manufacturer�sauthorized representatives or in accordancewith a code of practice developed by a nation-ally-recognized association or an independenttesting laboratory;

(C) Metal pipe sections and fittings thathave released product as a result of corrosionor other damage must be replaced. Fiberglasspipes and fittings may be repaired in accor-dance with the manufacturer�s specifications;

(D) Repaired tanks and piping must betightness tested in accordance with releasedetection methods 10 CSR 20-10.043(1)(C)and 10 CSR 20-10.044(1)(B) within thirty(30) days following the date of the completionof the repair, except as provided in the fol-lowing paragraphs�

1. The repaired tank is internallyinspected in accordance with a code of prac-tice developed by a nationally-recognizedassociation or an independent testing labora-tory;

2. The repaired portion of the UST sys-tem is monitored monthly for releases by one(1) of the release detection methods in 10CSR 20-10.043(1)(D)�(H); or

3. Another test method is used that isdetermined by the department to be no lessprotective of human health and the environ-

ment than those listed in paragraphs (2)(D)1.and 2.;

(E) Within six (6) months following therepair of any cathodically protected UST sys-tem, the cathodic protection system must betested with the methods for operation andmaintenance of corrosion protection in 10CSR 20-10.031(1)(B) and (C) to ensure thatit is operating properly; and

(F) UST system owners and operators mustmaintain records of each repair for theremaining operating life of the UST systemthat demonstrate compliance with therequirements of this rule.

AUTHORITY: sections 319.105, RSMo (Cum.Supp. 1989) and 644.041, RSMo (1986).*Original rule filed April 2, 1990, effectiveSept. 28, 1990.

*Original authority: 319.105, RSMo (1989) and 644.041,RSMo (1972), amended 1973.

10 CSR 20-10.034 Reporting and Record-keeping

PURPOSE: This rule explains how the ownerand operator must keep records demonstrat-ing compliance with the requirements of thischapter. These records must be furnished tothe department on request.

(1) Owners and operators of undergroundstorage tank (UST) systems must cooperatefully with inspections, monitoring and testingconducted by the department, as well asrequests for document submission, testingand monitoring by the owner or operator.

(A) Reporting. Owners and operators mustsubmit the following information to thedepartment:

1. Notification for all UST systems bythe notification requirements in 10 CSR 20-10.022;

2. Reports of all releases including sus-pected releases (10 CSR 20-10.050), spillsand overfills (10 CSR 20-10.053) and con-firmed releases (10 CSR 20-10.061);

3. Corrective actions planned or takenincluding initial abatement measures (10 CSR20-10.062), initial site characterization (10CSR 20-10.063), free product removal (10CSR 20-10.064), investigation of soil andgroundwater cleanup (10 CSR 20-10.065)and corrective action plan (10 CSR 20-10.066); and

4. A notification before permanent clo-sure or change in service (10 CSR 20-10.071).

(B) Recordkeeping. Owners and operatorsmust maintain the following information:

1. A corrosion expert�s analysis of sitecorrosion potential if corrosion protectionequipment is not used (10 CSR 20-10.020(1)(A)4. and (B)4.);

2. Documentation of operation of corro-sion protection equipment (10 CSR 20-10.031);

3. Documentation of UST systemrepairs (10 CSR 20-10.033(2)(F));

4. Recent compliance with releasedetection requirements (10 CSR 20-10.045);and

5. Results of the site investigation con-ducted at permanent closure (10 CSR 20-10.074).

(C) Availability and Maintenance ofRecords. Owners and operators must keep therecords required either�

1. At the UST site and immediatelyavailable for inspection by the department; or

2. At a readily available alternative siteand be provided for inspection to the depart-ment within three (3) working days or five (5)calendar days upon receipt of a writtenrequest. A written request shall be made inthe following manner:

A. The department shall provide awritten request at the time of inspection tosite personnel; or

B. In the cases of unattended sites orinspections conducted after normal businesshours (8:00 a.m. to 5:00 p.m., local time,Monday through Friday), written notice shallbe made by certified mail; or

3. If the owner or operator fails to meetthe requirements of paragraph (1)(C)2., thedepartment may order or otherwise requirethat owner or operator to maintain recordson-site per paragraph (1)(C)1.; or

4. In the case of permanent closurerecords required under 10 CSR 20-10.074,owners and operators are also provided withthe additional alternative of mailing closurerecords to the department if they cannot bekept at the site or an alternative site as indi-cated in this section.

DEPARTMENT OF NATURALRESOURCES

DIVISION OF ENVIRONMENTALQUALITY

WATER POLLUTION CONTROLPROGRAM

file:___________________________CountyUT_________________________________

14 CODE OF STATE REGULATIONS (8/31/97) Rebecca McDowell CookSecretary of State

10 CSR 20-10—NATURAL RESOURCES Division 20—Clean Water Commission

REQUEST FOR RECORDS UNDERGROUND STORAGE TANK

INSPECTION

Date:________________________________Time:________________________________

Pursuant to 10 CSR 20-10.034(1)(C)2. theDepartment of Natural Resources requeststhe records concerning the underground stor-age tanks facility located at:

Facility name:_________________________

Facility address:_______________________be provided to Missouri Department of Nat-ural Resources_______________________________Office

Mailing address:_______________________

Street address:____________________________________________________________

(City) (State) (Zip Code)within three (3) working days or five (5) cal-endar days of this notice. This request was made on ______________

____________________________________(Date & Time)

by:__________________________________(Inspector name)

____________________________________(Inspector office)

____________________________________(Inspector phone)

and was given to:

____________________________________(Site person name)

Signed:

____________________________________(Inspector)

AUTHORITY: sections 319.107, RSMo (Cum.Supp. 1989) and 644.021, RSMo (1986).*Original rule filed April 2, 1990, effectiveSept. 28, 1990. Amended: Filed Aug. 3,1993, effective April 9, 1994.

*Original authority: 319.107, RSMo (1989) and 644.021,RSMo (1972), amended 1973.

10 CSR 20-10.040 General Requirementsfor Release Detection for All UndergroundStorage Tank Systems

PURPOSE: This rule outlines the minimumrequirements for leak and spill detection sys-tems.

(1) Owners and operators of new and existingunderground storage tank (UST) systemsmust provide a method, or combination ofmethods, of release detection that�

(A) Can detect a release from any portionof the tank and the connected undergroundpiping that routinely contains product;

(B) Is installed, calibrated, operated andmaintained in accordance with the manufac-turer�s instructions, including routine mainte-nance and service checks for operability orrunning condition; and

(C) Meets the performance requirementsfor tanks in 10 CSR 20-10.043 or for pipingin 10 CSR 20-10.044, with any performanceclaims and their manner of determinationdescribed in writing by the equipment manu-facturer or installer. In addition, methodsused after December 22, 1990, except formethods permanently installed prior to thatdate, must be capable of detecting the leakrate or quantity specified for that tank methodin 10 CSR 20-10.043(1)(B)�(D) or pipingmethod in 10 CSR 20-10.044(1)(A) and (B)with a probability of detection of ninety-fivepercent (95%) and a probability of falsealarm of five percent (5%).

(2) When a release detection method fortanks in 10 CSR 20-10.043 or for piping in10 CSR 20-10.044 indicates a release mayhave occurred, owners and operators mustnotify the department in accordance with 10CSR 20-10.050�10 CSR 20-10.053.

(3) Owners and operators of all UST systemsmust comply with the release detectionrequirements of 10 CSR 20-10.040�10 CSR20-10.045 by the following dates based on theyear of installation:

(A) December 22, 1990 for all existingpressurized piping;

(B) September 28, 1990 for USTs installedbefore 1965, or of unknown age;

(C) December 22, 1990 for USTs installedduring 1965�1969;

(D) December 22, 1991 for USTs installedduring 1970�1974;

(E) December 22, 1992 for USTs installedduring 1975�1979;

(F) December 22, 1993 for USTs installedduring 1980�September 28, 1990; and

(G) Immediately upon installation for anyUSTs installed after September 28, 1990.

(4) Any existing UST system that cannotapply a method of release detection that com-plies with the requirements of 10 CSR 20-10.040�10 CSR 20-10.045 must completethe closure procedures in 10 CSR 20-10.070�10 CSR 20-10.074 by the date on

which release detection is required for thatUST system under section (3) of this rule.

AUTHORITY: sections 319.107 (Cum. Supp.1989) and 644.026, RSMo (Cum. Supp.1993).* Original rule filed April 2, 1990,effective Sept. 28, 1990. Amended: FiledAug. 3, 1993, effective April 9, 1994.

*Original authority: 319.107, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.041 Requirements forPetroleum Underground Storage Tank Sys-tems

PURPOSE: This rule outlines the options forleak detection at petroleum underground stor-age tanks.

(1) Owners and operators of petroleumunderground storage tanks (UST) systemsmust provide release detection for tanks andpiping as follows:

(A) Tanks. Tanks must be monitored atleast every thirty (30) days for releases usingone (1) of the methods listed in 10 CSR 20-10.043(1)(D)�(H) except that�

1. UST systems that meet new orupgraded standards in 10 CSR 20-10.020 or10 CSR 20-10.021 and the monthly invento-ry control requirements in 10 CSR 20-10.043(1)(A) or (B) may use tank tightnesstesting (10 CSR 20-10.043(1)(C)) at leastevery five (5) years until December 22, 1998or until ten (10) years after the tank isinstalled or upgraded under 10 CSR 20-10.021(2), whichever is later;

2. UST systems that do not meet theperformance standards in 10 CSR 20-10.020or 10 CSR 20-10.021 may use monthlyinventory controls (10 CSR 20-10.043(1)(A)or (B)) and annual tank tightness testing (10CSR 20-10.043(1)(C)) until December 22,1998, when the tank must be upgraded under10 CSR 20-10.021 or permanently closedunder 10 CSR 20-10.071; and

3. Tanks with capacity of five hundredfifty (550) gallons or less may use manualtank gauging (10 CSR 20-10.043(1)(B)); and

(B) Piping. Underground piping that rou-tinely contains regulated substances must bemonitored for releases in a manner that meetsone (1) of the following requirements:

1. Pressurized piping. Underground pip-ing that conveys regulated substances underpressure must�

A. Be equipped with an automaticline leak detector in 10 CSR 20-10.044(1)(A); and

CODE OF STATE REGULATIONS 15Rebecca McDowell Cook (8/31/97)Secretary of State

Chapter 10—Underground Storage Tanks—Technical Regulations 10 CSR 20-10

B. Have an annual line tightness testconducted in accordance with 10 CSR 20-10.044(1)(B) or have monthly monitoringconducted in accordance with 10 CSR 20-10.044(1)(C); and

2. Suction piping. Underground pipingthat conveys regulated substances under suc-tion must either have a line tightness test con-ducted at least every three (3) years and inaccordance with 10 CSR 20-10.044(1)(B) oruse a monthly monitoring method conductedin accordance with 10 CSR 20-10.044(1)(C).No release detection is required for suctionpiping that is designed and constructed tomeet the following standards:

A. The below-grade piping operatesat less than atmospheric pressure;

B. The below-grade piping is slopedso that the contents of the pipe will drainback into the storage tank if the suction isreleased;

C. Only one (1) check valve is includ-ed in each suction line;

D. The check valve is located direct-ly below and as close as practical to the suc-tion pump; and

E. A method is provided that allowscompliance with subparagraphs (1)(B)2.A.�D. of this rule to be readily determined (forexample, the check valve can be visuallyinspected).

AUTHORITY: sections 319.107, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990.

*Original authority: 319.107, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.042 Requirements for Haz-ardous Substance Underground StorageTank Systems

PURPOSE: This rule outlines the standardsfor leak detection on hazardous substanceunderground storage tanks.

(1) Owners and operators of hazardous sub-stance underground storage tank (UST) sys-tems must provide release detection thatmeets the following requirements:

(A) Release detection at existing UST sys-tems must meet the requirements forpetroleum UST systems in 10 CSR 20-10.041. By December 22, 1998, all haz-ardous substance UST systems must meet therelease detection requirements for new sys-tems in subsection (1)(B) of this rule;

(B) Release detection at new hazardoussubstance UST systems must meet the fol-lowing requirements:

1. Secondary containment systems mustbe designed, constructed and installed to�

A. Contain regulated substancesreleased from the tank system until they aredetected and removed;

B. Prevent the release of regulatedsubstances to the environment at any timeduring the operational life of the UST system;and

C. Be checked for evidence of arelease at least every thirty (30) days;

2. Double-walled tanks must bedesigned, constructed and installed to�

A. Contain a release from any portionof the inner tank within the outer wall; and

B. Detect the failure of the inner wall; 3. External liners (including vaults)

must be designed, constructed and installedto�

A. Contain one hundred percent(100%) of the capacity of the largest tankwithin its boundary;

B. Prevent the interference of precip-itation or groundwater intrusion with the abil-ity to contain or detect a release of regulatedsubstances; and

C. Surround the tank completely(that is, it is capable of preventing lateral aswell as vertical migration of regulated sub-stances);

4. Underground piping must beequipped with secondary containment thatsatisfies the requirements of paragraph(1)(B)1. of this rule (for example, trench lin-ers, jacketing of double-walled pipe). In addi-tion, underground piping that conveys regu-lated substances under pressure must beequipped with an automatic line leak detectorin 10 CSR 20-10.044(1)(A); and

5. Other methods of release detectionmay be used if owners and operators�

A. Demonstrate to the departmentthat an alternate method can detect a releaseof the stored substance as effectively as anyof the methods allowed in 10 CSR 20-10.043(1)(B)�(H) can detect a release ofpetroleum;

B. Provide information to the depart-ment on effective corrective action technolo-gies, health risks and chemical and physicalproperties of the stored substance and thecharacteristics of the UST site; and

C. Obtain approval from the depart-ment to use the alternate release detectionmethod before the installation and operationof the new UST system.

(2) The provisions of 10 CSR 25-7.265(2)(J)may be used to comply with this rule.

AUTHORITY: sections 319.107, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.

Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990.

*Original authority: 319.107, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.043 Methods of ReleaseDetection for Tanks

PURPOSE: This rule contains the require-ments that specific underground storage tankleak detection methods must meet.

Editor�s Note: The secretary of state hasdetermined that the publication of this rule inits entirety would be unduly cumbersome orexpensive. The entire text of the material ref-erenced has been filed with the secretary ofstate. This material may be found at theOffice of the Secretary of State or at theheadquarters of the agency and is available toany interested person at a cost established bystate law.

(1) Each method of release detection forunderground storage tanks (UST) used tomeet the requirements of petroleum UST leakdetection in 10 CSR 20-10.041 must meet thefollowing:

(A) Inventory Control. Product inventorycontrol (or another test of equivalent perfor-mance) must be conducted monthly to detecta release of at least one percent (1%) of flowthrough plus one hundred thirty (130) gallonson a monthly basis in the following manner:

1. Inventory volume measurements forregulated substance inputs, withdrawals andthe amount still remaining in the tank arerecorded each operating day on forms provid-ed by the department or on forms previouslyapproved by the department;

2. The equipment used is capable ofmeasuring the level of product over the fullrange of the tank�s height to the nearest one-eighth inch (1/8");

3. The regulated substance inputs arereconciled with delivery receipts by measure-ment of the tank inventory volume before andafter delivery;

4. Deliveries are made through a droptube that extends to within one foot (1') of thetank bottom;

5. Product dispensing is metered andrecorded within the local standards for metercalibration or an accuracy of six (6) cubicinches for every five (5) gallons of productwithdrawn;

6. The measurement of any water levelin the bottom of the tank is made to the near-est one-eighth inch (1/8") at least once amonth; and

16 CODE OF STATE REGULATIONS (8/31/97) Rebecca McDowell CookSecretary of State

10 CSR 20-10—NATURAL RESOURCES Division 20—Clean Water Commission

7. The practices described in the Amer-ican Petroleum Institute Publication 1621,Recommended Practice for Bulk Liquid StockControl at Retail Outlets, may be used, whereapplicable, as guidance in meeting therequirements of this subsection;

(B) Manual Tank Gauging. Manual tankgauging must meet the following require-ments:

1. Tank liquid level measurements aretaken at the beginning and ending of a periodof at least thirty-six (36) hours during whichno liquid is added to or removed from thetank;

2. Level measurements are based on anaverage of two (2) consecutive stick readingsat both the beginning and ending of the peri-od;

3. The equipment used is capable ofmeasuring the level of product over the fullrange of the tank�s height to the nearest one-eighth inch (1/8");

4. A leak is suspected and subject to therequirements of 10 CSR 20-10.050�10 CSR20-10.053 if the variation between beginningand ending measurements exceeds the follow-ing weekly or monthly standards:

A. Tanks of five hundred fifty (550)-gallon capacity or less are allowed a weeklystandard of ten (10) gallons per reading and amonthly average of five (5) gallons per read-ing;

B. Five hundred fifty-one to one thou-sand (551�1000)-gallon capacity tanks areallowed a difference of thirteen (13) gallonsper week and a monthly average of seven (7)gallons;

C. One thousand one to two thousand(1001�2000)-gallon capacity tanks areallowed a difference of twenty-six (26) gal-lons per week and a monthly average of thir-teen (13) gallons;

D. Five hundred fifty-one to onethousand (551�1000)-gallon capacity tankswith dimensions no greater than sixty-fourinches by seventy-three inches (64"×73") areallowed a difference of nine (9) gallons perweek and monthly average of four (4) gallons,provided that a period of at least forty-four(44) hours during which no liquid is added toor removed from the tank is allowed to passbetween tank liquid level measurements; and

E. One thousand (1000)-gallon capac-ity tanks with dimensions of forty-eight inch-es by one hundred twenty-eight inches(48"×128") are allowed a difference oftwelve (12) gallons per week and a monthlyaverage of six (6) gallons, provided that aperiod of at least fifty-eight (58) hours duringwhich no liquid is added to or removed fromthe tank is allowed to pass between tank liq-uid level measurements; and

5. Use of manual tank gauging mustcomply with the following size restrictions:

A. Tanks of five hundred fifty (550)gallons or less nominal capacity may use thisas the sole method of release detection;

B. Tanks of five hundred fifty-one toone thousand (551�1000)-gallon capacitywith dimensions no greater than sixty-fourinches by seventy-three inches (64"×73")and tanks of one thousand (1000)-galloncapacity with dimensions of forty-eight inch-es by one hundred twenty-eight inches(48"×128") may use this as the sole methodof release detection;

C. Tanks of five hundred fifty-one totwo thousand (551�2000) gallons may usethe method in place of inventory control in 10CSR 20-10.043(1)(A); and

D. Tanks of greater than two thousand(2000) gallons nominal capacity may not usethis method for release detection;

(C) Tank Tightness Testing. Tank tightnesstesting (or similar test) must be capable ofdetecting a one-tenth (0.1)-gallon-per-hourleak rate from any portion of the tank thatroutinely contains product while accountingfor the effects of thermal expansion or con-traction of the product, vapor pockets, tankdeformation, evaporation or condensationand the location of the water table;

(D) Automatic Tank Gauging. Equipmentfor automatic tank gauging that tests for theloss of product and conducts inventory con-trol must meet the following requirements:

1. The automatic product level monitortest can detect a two-tenths (0.2)-gallon-per-hour leak rate from any portion of the tankthat routinely contains product; and

2. Inventory control (or equivalent test)meeting the requirements in 10 CSR 20-10.043(1)(A) is conducted;

(E) Vapor Monitoring. Testing or monitor-ing for vapors within the soil gas of the exca-vation zone must meet the following require-ments:

1. The materials used as backfill are suf-ficiently porous and permeable (for example,gravel, sand or crushed rock) to readily allowdiffusion of vapors from releases into theexcavation area;

2. The stored regulated substance, or atracer compound placed in the tank system, issufficiently volatile (for example, gasoline) toresult in a vapor level that is detectable by themonitoring devices located in the excavationzone in the event of a release from the tank;

3. The measurement of vapors by themonitoring device is not rendered inoperativeby the groundwater, rainfall or soil moistureor other known interferences so that a releasecould go undetected for more than thirty (30)days;

4. The level of background contamina-tion in the excavation zone will not interferewith the method used to detect releases fromthe tank;

5. The vapor monitors are designed andoperated to detect any significant increase inconcentration above background of the regu-lated substance stored in the tank system, acomponent(s) of that substance or a tracercompound placed in the tank system;

6. In the UST excavation zone, the siteis assessed to ensure compliance with therequirements in paragraphs (1)(E)1.�4. ofthis rule and to establish the number andpositioning of monitoring wells that willdetect releases within the excavation zonefrom any portion of the tank that routinelycontains product; and

7. Monitoring wells are clearly markedand secured to avoid unauthorized access andtampering;

(F) Groundwater Monitoring. Testing ormonitoring for liquids on the groundwatermust meet the following requirements:

1. The regulated substance stored isimmiscible in water and has a specific gravi-ty of less than one (1);

2. The groundwater is within twenty feet(20') from the ground surface and thehydraulic conductivity of the soil(s) betweenthe UST system and the monitoring wells ordevices is at least one hundredth centimeterper second (0.01 cm/sec) (for example, thesoil should consist of gravels, coarse to medi-um sands, coarse silts or other permeablematerials);

3. The slotted portion of the monitoringwell casing must be designed to preventmigration of natural soils or filter pack intothe well and to allow entry of regulated sub-stance on the water table into the well underboth high and low groundwater conditions;

4. Monitoring wells shall be sealed fromthe ground surface to the top of the filterpack;

5. Monitoring wells or devices shallintercept the excavation zone or are as closeto it as is technically feasible;

6. The continuous monitoring devices ormanual methods used can detect the presenceof at least one-eighth inch (1/8") of free prod-uct on top of the groundwater in the monitor-ing wells;

7. The site is assessed within and imme-diately below the UST system excavationzone to ensure compliance with the require-ments in paragraphs (1)(F)1.�5. of this rule.The site assessment also establishes thenumber and positioning of monitoring wellsor devices that will detect releases from anyportion of the tank that routinely containsproduct; and

CODE OF STATE REGULATIONS 17Rebecca McDowell Cook (8/31/97)Secretary of State

Chapter 10—Underground Storage Tanks—Technical Regulations 10 CSR 20-10

8. Monitoring wells are clearly markedand secured to avoid unauthorized access andtampering;

(G) Interstitial Monitoring. Interstitialmonitoring between the UST system and asecondary barrier immediately around orbeneath it may be used, but only if the systemis designed, constructed and installed todetect a leak from any portion of the tank thatroutinely contains product and also meets one(1) of the following requirements:

1. For double-walled UST systems, thesampling or testing method can detect arelease through the inner wall in any portionof the tank that routinely contains product;

2. For UST systems with a secondarybarrier within the excavation zone, the sam-pling or testing method used can detect arelease between the UST system and the sec-ondary barrier.

A. The secondary barrier around orbeneath the UST system consists of artificial-ly constructed material that is sufficientlythick and impermeable (less than one mil-lionth centimeter per second (10-6 cm/sec)for the regulated substance stored) to direct arelease to the monitoring point and permit itsdetection.

B. The barrier is compatible with theregulated substance stored so that a releasefrom the UST system will not cause a deteri-oration of the barrier allowing a release topass through undetected.

C. For cathodically protected tanksthe secondary barrier must be installed sothat it does not interfere with the proper oper-ation of the cathodic protection system.

D. The groundwater, soil moisture orrainfall will not render the testing or sam-pling method used inoperative so that arelease could go undetected for more thanthirty (30) days.

E. The site is assessed to ensure thatthe secondary barrier is always above thegroundwater and not in a twenty-five (25)-year flood plain, unless the barrier and mon-itoring designs are for use under these condi-tions.

F. Monitoring wells are clearlymarked and secured to avoid unauthorizedaccess and tampering;

3. For tanks with an internally fitted lin-er, an automated device can detect a releasebetween the inner wall of the tank and the lin-er is compatible with the substance stored;and

4. The provisions outlined in the SteelTank Institute�s Standard for Dual WallUnderground Storage Tanks may be used asguidance for aspects of the design and con-struction of underground steel double-walledtanks; and

(H) Other Methods. Any other type ofrelease detection method, or combination ofmethods, can be used if�

1. It can detect a two-tenths (0.2)-gal-lon-per-hour leak rate or a release of onehundred fifty (150) gallons within a monthwith a probability of detection of ninety-fivepercent (95%) and a probability of falsealarm of five percent (5%); or

2. The department may approve anothermethod if the owner and operator can demon-strate that the method can detect a release aseffectively as any of the methods allowed insubsections (1)(C)�(H) of this rule. In com-paring methods, the department shall consid-er the size of release that the method candetect and the frequency and reliability withwhich it can be detected. If the method isapproved, the owner and operator must com-ply with any conditions imposed by thedepartment on its use to ensure the protectionof human health and the environment.

AUTHORITY: sections 319.107, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990. Amended:Filed Aug. 3, 1993, effective April 9, 1994.

*Original authority: 319.107, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.044 Methods of ReleaseDetection for Piping

PURPOSE: This rule describes the require-ments of leak detection for the piping onunderground storage tanks.

(1) Each method of release detection for pip-ing used to meet the requirements of releasedetection for underground storage tanks(UST) in 10 CSR 20-10.041 must be con-ducted in the following manner:

(A) Automatic Line Leak Detectors. Meth-ods which alert the operator to the presenceof a leak by restricting or shutting off the flowof regulated substances through piping ortriggering an audible or visual alarm may beused only if they detect leaks of three (3) gal-lons per hour at ten (10) pounds per square-inch line pressure within one (1) hour. Anannual test of the operation of the leak detec-tor must be conducted in accordance with themanufacturer�s requirements;

(B) Line Tightness Testing. A periodic testof piping may be conducted only if it candetect a one-tenth (0.1)-gallon-per-hour leakrate at one and one-half (1.5) times the oper-ating pressure; and

(C) Applicable Tank Methods. Any of themethods in 10 CSR 20-10.043(1)(E)�(H)

may be used if they are designed to detect arelease from any portion of the undergroundpiping that routinely contains regulated sub-stances.

AUTHORITY: sections 319.107, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990.

*Original authority: 319.107, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.045 Release DetectionRecordkeeping

PURPOSE: This rule describes the recordsthat must be maintained for monthly releasedetection activity.

(1) All underground storage tank (UST) sys-tem owners and operators must maintainrecords in 10 CSR 20-10.034 demonstratingcompliance with applicable release detectionrequirements in 10 CSR 20-10.040�10 CSR20-10.045. These records must include thefollowing:

(A) All written performance claims of anyrelease detection system used, and the man-ner in which these claims have been justifiedor tested by the equipment manufacturer orinstaller, must be maintained for five (5)years or for another reasonable period of timedetermined by the department from the dateof installation;

(B) The results of any sampling, testing ormonitoring must be maintained for at leastone (1) year, or for another reasonable peri-od of time determined by the department,except that the results of tank tightness testingconducted in accordance with 10 CSR 20-10.043(1)(C) must be retained until the nexttest is conducted; and

(C) Written documentation of all calibra-tion, maintenance and repair of release detec-tion equipment permanently located on-sitemust be maintained for at least one (1) yearafter the servicing work is completed. Anyschedules of required calibration and mainte-nance provided by the release detectionequipment manufacturer must be retained forfive (5) years from the date of installation.

AUTHORITY: sections 319.107, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990.

*Original authority: 319.107, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

18 CODE OF STATE REGULATIONS (8/31/97) Rebecca McDowell CookSecretary of State

10 CSR 20-10—NATURAL RESOURCES Division 20—Clean Water Commission

10 CSR 20-10.050 Reporting of SuspectedReleases

PURPOSE: This rule describes the steps forreporting leaks and spills.

(1) Owners and operators of undergroundstorage tank (UST) systems must report to thedepartment within twenty-four (24) hours andfollow the procedures for release investiga-tion and confirmation in 10 CSR 20-10.052for any of the following conditions:

(A) The discovery by owners and operatorsor others of released regulated substances atthe UST site or in the surrounding area (suchas the presence of free product or vapors insoils, basements, sewer and utility lines andnearby surface water);

(B) Unusual operating conditions observedby owners and operators (such as the erraticbehavior of product dispensing equipment,the sudden loss of product from the UST sys-tem or an unexplained presence of water inthe tank), unless system equipment is foundto be defective but not leaking and is imme-diately repaired or replaced; and

(C) Monitoring results from a releasedetection method required under 10 CSR 20-10.041 and 10 CSR 20-10.042 that indicate arelease may have occurred unless�

1. The monitoring device is found to bedefective and is immediately repaired, recali-brated or replaced and additional monitoringdoes not confirm the initial result; and

2. In the case of inventory control, asecond month of data does not confirm theinitial result.

AUTHORITY: sections 319.107, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990.

*Original authority: 319.107, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.051 Investigation Due toOff-Site Impacts

PURPOSE: This rule describes the require-ments for off-site investigations followingreported or suspected releases.

(1) When required by the department, ownersand operators of underground storage tank(UST) systems must follow the steps for con-firmation of a release in 10 CSR 20-10.052 todetermine if the UST system is the source ofthe off-site impacts. These impacts includethe discovery of regulated substances such asthe presence of free product or vapors insoils, basements, sewer and utility lines and

nearby surface and drinking waters that havebeen observed by the department or broughtto its attention by another party.

AUTHORITY: sections 319.109, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990.

*Original authority: 319.109, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.052 Release Investigationand Confirmation Steps

PURPOSE: This rule describes the stepsneeded to verify a release.

(1) Unless corrective action is initiated in 10CSR 20-10.060�10 CSR 20-10.067, ownersand operators must immediately investigateand confirm all suspected releases of regulat-ed substances requiring reporting under 10CSR 20-10.050 within seven (7) days oranother reasonable time period specified bythe department using either the followingsteps or another procedure approved by thedepartment:

(A) System Test. Owners and operatorsmust conduct tests (tightness testing of tanksin 10 CSR 20-10.043(1)(C) and piping in 10CSR 20-10.044(1)(B)) to determine whethera leak exists in that portion of the tank thatroutinely contains product or the attacheddelivery piping, or both.

1. Owners and operators must repair,replace or upgrade the underground storagetank (UST) system, and begin correctiveaction in 10 CSR 20-10.060�10 CSR 20-10.067 if the test results for the system, tankor delivery piping indicate that a leak exists.

2. Further investigation is not requiredif the test results for the system, tank anddelivery piping do not indicate that a leakexists and if environmental contamination isnot the basis for suspecting a release.

3. Owners and operators must conducta site check as described in subsection (1)(B)of this rule if the test results for the system,tank and delivery piping do not indicate thata leak exists but environmental contaminationis the basis for suspecting a release; or

(B) Site Check. Owners and operatorsmust measure for the presence of a releasewhere contamination is most likely to be pre-sent at the UST site. In selecting sampletypes, sample locations and measurementmethods, owners and operators must consid-er the nature of the stored substance, the typeof initial alarm or cause for suspicion, thetype of backfill, the depth of groundwater and

other factors appropriate for identifying thepresence and source of the release.

1. If the site check indicates that arelease has occurred, owners and operatorsmust begin corrective action in accordancewith 10 CSR 20-10.060�10 CSR 20-10.067;or

2. If the results of the site check do notindicate that a release has occurred, theinvestigation may stop.

(2) Owners and operators shall follow a writ-ten procedure. To comply with this rule, thedepartment�s Site Characterization GuidanceDocument may be used as a written proce-dure. Other written procedures may be usedwith prior written approval of the depart-ment.

AUTHORITY: sections 319.109, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990. Amended:Filed Aug. 3, 1993, effective April 9, 1994.

*Original authority: 319.107, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.053 Reporting and Cleanupof Spills and Overfills

PURPOSE: This rule describes the steps forreporting and cleanup of spills.

Editor�s Note: The secretary of state hasdetermined that the publication of this rule inits entirety would be unduly cumbersome orexpensive. The entire text of the material ref-erenced has been filed with the secretary ofstate. This material may be found at theOffice of the Secretary of State or at the head-quarters of the agency and is available to anyinterested person at a cost established bystate law.

(1) Owners and operators of undergroundstorage tank (UST) systems must contain andimmediately cleanup a spill or overfill. Thespill or overfill must be reported to thedepartment within twenty-four (24) hours.Owners and operators must begin correctiveaction in accordance with 10 CSR 20-10.060�10 CSR 20-10.067 in the followingcases:

(A) Spill or overfill of petroleum thatresults in a release to the environment thatexceeds twenty-five (25) gallons or that caus-es a sheen on nearby surface water; and

(B) Spill or overfill of a hazardous sub-stance that results in a release to the environ-ment that equals or exceeds its reportable

CODE OF STATE REGULATIONS 19Rebecca McDowell Cook (8/31/97)Secretary of State

Chapter 10—Underground Storage Tanks—Technical Regulations 10 CSR 20-10

quantity under Comprehensive Environmen-tal Response Compensation and Liability Actof 1980 (CERCLA) (40 CFR 302).

(2) Owners and operators of UST systemsmust contain and immediately clean up a spillor overfill of petroleum that is less than twen-ty-five (25) gallons or another reasonableamount specified by the department and aspill or overfill of a hazardous substance thatis less than the reportable quantity. If cleanupcannot be accomplished within twenty-four(24) hours, owners and operators must imme-diately notify the department.

(3) A release of a hazardous substance equalto or in excess of its reportable quantity mustalso be reported immediately (rather thanwithin twenty-four (24) hours) to the Nation-al Response Center under Sections 102 and103 of CERCLA (40 CFR 302.6) and toappropriate state and local authorities underTitle III of the Superfund Amendments andReauthorization Act of 1986 (40 CFR355.40).

AUTHORITY: sections 319.109, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990.

*Original authority: 319.109, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.060 Release Response andCorrective Action

PURPOSE: This rule establishes general pro-cedures for responding to leaks of spills atunderground storage tanks.

(1) Owners and operators of petroleum orhazardous substance underground storagetank (UST) systems must comply, in responseto a confirmed release from the UST system,with the requirements of 10 CSR 20-10.060�10 CSR 20-10.067 except for USTsexcluded under 10 CSR 20-10.010(2) andUST systems subject to the Resource Conser-vation and Recovery Act (RCRA), Subtitle Ccorrective action requirements under Section3004(u).

AUTHORITY: sections 319.109, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990.

*Original authority: 319.109, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.061 Initial Release Response

PURPOSE: This rule describes the immediatesteps owners and operators of a leakingunderground storage tank must take.

(1) Upon confirmation of a release in 10 CSR20-10.052, or after a release from the under-ground storage tank (UST) system is identi-fied in any other manner, owners and opera-tors must perform the following initialresponse actions within twenty-four (24)hours of a release:

(A) Report the release to the department(for example, by telephone or electronicmail);

(B) Take immediate action to prevent anyfurther release of the regulated substance intothe environment; and

(C) Identify and mitigate fire, explosionand vapor hazards.

AUTHORITY: sections 319.109, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990.

*Original authority: 319.109, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.062 Initial Abatement Mea-sures and Site Check

PURPOSE: This rule describes the first stepsto stop the spread of the release and findingthe extent of the release.

(1) Unless directed to do otherwise by thedepartment, owners and operators must per-form the following abatement measures:

(A) Remove as much of the regulated sub-stance from the underground storage tank(UST) system as is necessary to prevent fur-ther release to the environment;

(B) Visually inspect any above-groundreleases or exposed below-ground releasesand prevent further migration of the releasedsubstance into surrounding soils and ground-water;

(C) Continue to monitor and mitigate anyadditional fire and safety hazards posed byvapors or free product that have migratedfrom the UST excavation zone and enteredinto subsurface structures such as sewers orbasements;

(D) Remedy hazards posed by contaminat-ed soils that are excavated or exposed as aresult of release confirmation, site investiga-tion, abatement or corrective action activi-ties. If these remedies include treatment ordisposal of soils, the owner and operator

must comply with applicable state and localrequirements;

(E) Measure for the presence of a releasewhere contamination is most likely to be pre-sent at the UST site, unless the presence andsource of the release have been confirmed inaccordance with the site check required by 10CSR 20-10.052(1)(B) or the closure siteassessment of 10 CSR 20-10.072(1). Inselecting sample types, sample locations andmeasurement methods, the owner and opera-tor must consider the nature of the storedsubstance, the type of backfill, depth togroundwater and other factors as appropriatefor identifying the presence and source of therelease; and

(F) Investigate to determine the possiblepresence of free product and begin free prod-uct removal as soon as practicable in 10 CSR20-10.064.

(2) Within twenty (20) days after release con-firmation, owners and operators must submita report to the department summarizing theinitial abatement steps taken under section (1)of this rule and any resulting information.

AUTHORITY: sections 319.109, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990.

*Original authority: 319.109, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.063 Initial Site Characteri-zation

PURPOSE: This rule describes the steps forinvestigation of a release.

(1) Unless directed to do otherwise by thedepartment, owners and operators mustassemble information about the site and thenature of the release, including informationgained while confirming the release or com-pleting the initial abatement measures in 10CSR 20-10.060 and 10 CSR 20-10.061. Thisinformation must include, but is not neces-sarily limited to, the following:

(A) Data on the nature and estimated quan-tity of release;

(B) Data from available sources or siteinvestigations concerning the following fac-tors: surrounding populations, water quality,use and approximate locations of wells poten-tially affected by the release, subsurface soilconditions, locations of subsurface sewers,climatological conditions and land use;

(C) Results of the site check requiredunder 10 CSR 20-10.062(1)(E); and

20 CODE OF STATE REGULATIONS (8/31/97) Rebecca McDowell CookSecretary of State

10 CSR 20-10—NATURAL RESOURCES Division 20—Clean Water Commission

(D) Results of the free product investiga-tions required under 10 CSR 20-10.062(1)(F)to be used by owners and operators to deter-mine whether free product must be recoveredunder 10 CSR 20-10.064.

(2) Within forty-five (45) days of release con-firmation, owners and operators must submitthe information collected in compliance withsection (1) of this rule to the department or ina format and according to the schedulerequired by the department.

AUTHORITY: sections 319.109, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990.

*Original authority: 319.109, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.064 Free-Product Removal

PURPOSE: This rule requires spilled, freeproduct to be collected immediately.

(1) At sites where the investigation revealsfree product under 10 CSR 20-10.062(1)(F),owners and operators must remove as muchfree product as practicable as determined bythe department. Any actions initiated under10 CSR 20-10.061�10 CSR 20-10.063 orpreparation for actions required under 10CSR 20-10.065�10 CSR 20-10.066 mustalso be continued. In meeting the require-ments of this rule, owners and operatorsmust�

(A) Remove free product to minimize thespread of contamination into previouslyuncontaminated zones. The recovery and dis-posal techniques must be appropriate to thehydrogeologic conditions at the site. Recov-ered by-products must be treated, dischargedor disposed in compliance with applicablelocal, state and federal regulations;

(B) Use abatement of free-product migra-tion as a minimum objective for free productremoval;

(C) Handle any flammable products in asafe and competent manner to prevent fires orexplosions; and

(D) Prepare and submit to the departmenta free-product removal report, within forty-five (45) days after confirming a release,unless otherwise directed by the department.The report shall provide at least the followinginformation:

1. The name of the person(s) responsiblefor implementing the free product removalmeasures;

2. The estimated quantity, type andthickness of free product observed or mea-sured in wells, boreholes and excavations;

3. The type of free-product recovery sys-tem used;

4. Whether any discharge will take placeon-site or off-site during the recovery opera-tion and the location of this discharge;

5. The type of treatment applied to, andthe effluent quality expected from, any dis-charge;

6. The steps that have been or are beingtaken to obtain necessary permits for any dis-charge; and

7. The disposition of the recovered freeproduct.

AUTHORITY: sections 319.109, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990.

*Original authority: 319.109, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.065 Investigations for Soiland Groundwater Cleanup

PURPOSE: This rule describes the proce-dures for soil and groundwater investiga-tions.

Editor�s Note: The secretary of state hasdetermined that the publication of this rule inits entirety would be unduly cumbersome orexpensive. The entire text of the material ref-erenced has been filed with the secretary ofstate. This material may be found at theOffice of the Secretary of State or at the head-quarters of the agency and is available to anyinterested person at a cost established bystate law.

(1) Owners and operators must conductinvestigations of the release, the release siteand the surrounding area to determine the fullextent and location of soils contaminated bythe release and the presence and concentra-tions of dissolved product contamination inthe groundwater if any of the following con-ditions exist:

(A) There is evidence that groundwaterwells have been affected by the release (forexample, as found during release confirma-tion or previous corrective action measures);

(B) Free product is found to need recoveryin compliance with 10 CSR 20-10.064;

(C) There is evidence that contaminatedsoils may be in contact with groundwater asfound during the initial response measures orinvestigations required under 10 CSR 20-10.060�10 CSR 20-10.064; or

(D) The department requests an investiga-tion based on the potential effects of contam-inated soil or groundwater on nearby surfaceand ground water resources.

(2) Owners and operators must submit theinformation collected under section (1) of thisrule as soon as practicable or in accordancewith a schedule established by the depart-ment.

(3) Owners and operators shall follow a writ-ten procedure. To comply with this rule, thedepartment�s Site Characterization GuidanceDocument may be used as a written proce-dure. Other written procedures may be usedwith prior written approval of the depart-ment.

AUTHORITY: sections 319.109, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990. Amended:Filed Aug. 3, 1993, effective April 9, 1994.

*Original authority: 319.107, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.066 Corrective Action Plan

PURPOSE: This rule lists the requirementsfor corrective action plans for cleanup ofreleases from underground storage tank sites.

Editor�s Note: The secretary of state hasdetermined that the publication of this rule inits entirety would be unduly cumbersome orexpensive. The entire text of the material ref-erenced has been filed with the secretary ofstate. This material may be found at theOffice of the Secretary of State or at the head-quarters of the agency and is available to anyinterested person at a cost established bystate law.

(1) Owners and operators are responsible forsubmitting a plan that provides for adequateprotection of human health and the environ-ment, as determined by the department, afterfulfilling the requirements for release report-ing and investigation in 10 CSR 20-10.061�10 CSR 20-10.063. Owners and operatorsmust modify their plan as necessary to meetthis standard.

(A) The department may require ownersand operators to submit additional informa-tion or to develop and submit a correctiveaction plan for responding to contaminatedsoils and groundwater at any point afterreviewing the information submitted forrelease reporting and investigation in 10 CSR20-10.061�10 CSR 20-10.063. If a plan is

CODE OF STATE REGULATIONS 21Rebecca McDowell Cook (8/31/97)Secretary of State

Chapter 10—Underground Storage Tanks—Technical Regulations 10 CSR 20-10

required, owners and operators must submitthe plan according to a schedule and formatestablished by the department.

(B) Owners and operators may choose tosubmit a corrective action plan for respond-ing to contaminated soil and groundwaterafter fulfilling the requirements of 10 CSR20-10.061�10 CSR 20-10.063.

(2) The department will approve the correc-tive action plan only after ensuring thatimplementation of the plan will adequatelyprotect human health, safety and the environ-ment. In making this determination thedepartment should consider the following fac-tors as appropriate:

(A) The physical and chemical characteris-tics of the regulated substance, including itstoxicity, persistence and potential for migra-tion;

(B) The hydrogeologic characteristics ofthe facility and the surrounding area;

(C) The proximity, quality and current andfuture uses of nearby surface and groundwater;

(D) The potential effects of residual con-tamination on nearby surface and groundwater;

(E) An exposure assessment; and(F) Any information assembled in 10 CSR

20-10.060�10 CSR 20-10.067.

(3) Upon approval of the corrective actionplan, or as directed by the department, own-ers and operators must implement the planincluding modifications to the plan made bythe department. Owners and operators mustmonitor, evaluate and report the results ofimplementing the plan in accordance with aschedule and in a format established by thedepartment.

(4) Owners and operators, in the interest ofminimizing environmental contamination andpromoting more effective clean-up, maybegin clean-up of soil and groundwaterbefore the corrective action plan is approvedprovided that they�

(A) Notify the department of their inten-tion to begin clean-up;

(B) Comply with any conditions imposedby the department, including halting clean-upor mitigating adverse consequences fromclean-up activities; and

(C) Incorporate these self-initiated clean-up measures in the corrective action plan thatis submitted to the department for approval.

(5) Owners and operators shall follow a writ-ten procedure. To comply with this rule, thedepartment�s Corrective Action GuidanceDocument may be used as a written proce-dure. Other written procedures may be used

with prior written approval of the depart-ment.

AUTHORITY: sections 319.109, (Cum. Supp.1989) and 644.026, RSMo (Cum. Supp.1993).* Original rule filed April 2, 1990,effective Sept. 28, 1990. Amended: FiledAug. 3, 1993, effective April 9, 1994.

*Original authority: 319.109, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.067 Public Participation

PURPOSE: This rule establishes proceduresfor public participation during correctiveaction plans.

(1) For each confirmed release that requires acorrective action plan, the department mustprovide notice to the public by meansdesigned to reach those members of the pub-lic directly affected by the release and theplanned corrective action. This notice mayinclude, but is not limited to, public notice inlocal newspapers, block advertisements, pub-lic service announcements, publication in astate register, letters to individual householdsor personal contacts by field staff.

(2) Site release information and decisions bythe department concerning the correctiveaction plan are available to the public forinspection upon request.

(3) Before approving any corrective actionplan, the department may hold a public meet-ing to consider comments on the proposedcorrective action plan if there is sufficientpublic interest or for any other reason.

(4) The department must give public notice insection (1) of this rule if implementation ofan approved corrective action plan does notachieve the established clean-up levels in theplan and termination of that plan is underconsideration by the department.

AUTHORITY: sections 319.109, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990.

*Original authority: 319.109, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.068 Risk-Based Clean-UpLevels

PURPOSE: This rule sets clean-up levels forunderground storage tank corrective actionsand for site assessment, site characterization,

and workplan development, which are allstages in developing clean-up levels. The rulealso sets deed notice language to assure thatthe site is not used in a manner which wouldpose unacceptable risk or exposure. The rulerequires that sites be ranked and that theranking be used to allocate staff and funds.

PUBLISHER�S NOTE: The publication of thefull text of the material that the adoptingagency has incorporated by reference in thisrule would be unduly cumbersome or expen-sive. Therefore, the full text of that materialwill be made available to any interested per-son at both the Office of the Secretary of Stateand the office of the adopting agency, pur-suant to section 536.031.4, RSMo. Suchmaterial will be provided at the cost estab-lished by state law.

(1) Applicability. This rule applies to allcleanups of petroleum releases from under-ground storage tanks (USTs).

(2) Upon being so directed by the depart-ment, the UST remediator shall conduct apreliminary assessment of the site.

(A) The requirement for a preliminaryassessment is waived if permanent closure isbeing conducted, or significant contamina-tion is known to exist at the site, and thedepartment has been notified of a release asrequired in 10 CSR 24-3.010(1).

(B)The preliminary assessment shall beconducted according to department guidance.

(3) The department will evaluate the resultsof the preliminary assessment to rank the siterelative to other sites for further characteriza-tion and/or corrective action.

(A) If the preliminary assessment showscontamination levels below the action levelsoutlined in the department�s undergroundstorage tank closure guidance document, thedepartment will require no further action atthe site.

(B) If, in accordance with subsection(3)(A) of this rule, the department determinesthat no further action is required at a site, andif subsequent information becomes availableto indicate that contamination may be presentat the site at levels which may threaten humanhealth or the environment, the departmentmay require additional investigation or sitecharacterization and/or corrective action.

(4) If full site characterization is required bythe department, due to known contaminationor in accordance with subsection (3)(B) ofthis rule, the UST remediator shall conductthe site characterization according to depart-ment guidance.

22 CODE OF STATE REGULATIONS (8/31/97) Rebecca McDowell CookSecretary of State

10 CSR 20-10—NATURAL RESOURCES Division 20—Clean Water Commission

(5) The department will review the site char-acterization and rank the site relative to othersites based on site conditions as reflected inthe site characterization and the potential riskto human health and/or the environment.

(A) The rank assigned to the site will beused to prioritize department actions, includ-ing, but not limited to review of documents,pre-approval of costs and reimbursement ofcosts, in regard to the site.

(B) The department will not require furtheraction at sites that the department deems notto pose a risk to human health and/or theenvironment, unless there is a change inknown conditions at the site that wouldupgrade its priority, as determined by thedepartment.

(6) Except as provided in section (8) of thisrule, site clean-up objectives will be set asfollows:

(A) Site clean-up objectives for the cleanupof petroleum released from underground stor-age tanks will be set by using the scoringmatrix and the groundwater clean-up stan-dards as outlined in the department�s under-ground storage tank closure guidance docu-ment.

(B) (Reserved) (Note: The soil scoringmatrix is a site-specific risk-based methodwhich accounts for future land use and otherconsiderations. Upon further developmentand review, this method or another whichalso meets statutory requirements, will be setforth in this section.)

(7) Site clean-up objectives and workplansare subject to approval by the department.Such approval must be granted in writing pri-or to implementation of the workplan.

(8) For all sites which are cleaned up to meetlevels less stringent than (higher than) thoseset according to section (6) of this rule, theUST remediator shall file a document in thechain of title of the property. The documentshall state that the contaminant levels weredeemed acceptable by the department, basedon the land use and other considerations, atthe time of cleanup.

(A) If the UST remediator is a person oth-er than the landowner, the UST remediatorshall provide a copy of the document which isto be filed in the chain of title for the proper-ty, by certified mail to the landowner.

(B) The language of the document to befiled in the chain of title shall include the fol-lowing:

NOTICE OF ACCEPTABLE LANDUSE(S) OF UNDERGROUND STORAGE

TANK SITE

Owner of Record: (Landowner�s Name)

Site Description: (Site Name And LegalDescription)

The above-described real property, ownedby (Landowner�s Name) and located in theCounty of (County Name) and State of Mis-souri, is the site of an underground storagetank which was (Removed/Closed) on (Date).The site cleanup was accepted as complete bythe Missouri Department of NaturalResources on (Date), in accordance with theapplicable requirements of Title 10, Division25, Chapters 10 through 12 of the Code ofState Regulations which were in effect at thetime of cleanup. The contaminant levelsremaining on the site are suitable for (Com-mercial/Light Industrial/Heavy Industrial/Other Specified) use.

In witness whereof I hereunto set my handthis _____ day of ___, 19___.

____________________________________(Office)

____________________________________(Name)

____________________________________(Title)

(C) No person may substantially changethe manner in which a site with a documentfiled in the chain of title under this section isused without the prior written approval of thedirector or the director�s designee.

1. Requests for approval of change inuse of real property must be submitted inwriting to the director�s office no less thansixty (60) days prior to the planned change inuse of real property. In the event the directordoes not respond within sixty (60) days afterthe request is received, the request will beconsidered to be approved as submitted.

2. The director will evaluate the requestto determine whether the change in use ofreal property is likely to result in increasedexposure of persons or the environment orspread of contamination.

3. If the change in use of real propertyis not likely to result in increased exposure ofpersons or the environment or spread of con-tamination, the director shall provide writtenapproval.

(D) When the director finds that a sitewhich has had a document filed in the chainof title under this section has been furthercleaned up to meet or exceed (lower levelsthan) the standards described in section (6) ofthis rule, the director shall direct the USTremediator to file a second document in thechain of title. The document shall include the

language in subsection (8)(B) of this rule, andshall describe the land uses for which the newcontaminant levels are suitable.

AUTHORITY: sections 319.111, RSMo (1994)and 319.109 and 319.137, RSMo (Cum.Supp. 1996).* Original rule filed Jan. 2,1996, effective Aug. 30, 1996. Amended:Filed Jan. 14, 1997, effective Sept. 30, 1997.

*Original authority: 319.109, RSMo (1989), amended1995; 319.111, RSMo (1984); and 319.127, RSMo (1989),amended 1992, 1993.

10 CSR 20-10.070 Temporary Closure

PURPOSE: This rule contains the proceduresfor placing underground storage tanks out ofservice or temporarily closing undergroundstorage tanks.

(1) When an underground storage tank (UST)system is temporarily closed, owners andoperators must continue operation andmaintenance of corrosion protection in 10CSR 20-10.031 and release detection in 10CSR 20-10.040�10 CSR 20-10.045. Releasereporting, investigation and corrective actionin 10 CSR 20-10.050�10 CSR 20-10.067must be performed if a release is suspected orconfirmed. If the UST system is empty,release detection is not required. The USTsystem is empty when all materials have beenremoved so that no more than one inch (1�)(or two and one-half (2.5) centimeters) ofresidue or three-tenths percent (0.3%) byweight of the total capacity of the UST sys-tem remains.

(2) Owners and operators must also complywith the following requirements when a USTsystem is temporarily closed for three (3)months or more:

(A) Leave vent lines open and functioning;and

(B) Cap and secure all other lines, pumps,manways and ancillary equipment.

(3) When a UST system is temporarily closedfor more than twelve (12) months, ownersand operators must permanently close theUST system if it does not meet either perfor-mance standards in 10 CSR 20-10.020 fornew UST systems or the upgrading require-ments in 10 CSR 20-10.021 except that thespill and overfill equipment requirements donot have to be met. Owners and operatorsmust permanently close the substandard USTsystems at the end of this twelve (12)-monthperiod in accordance with 10 CSR 20-10.071�10 CSR 20-10.074, unless the

CODE OF STATE REGULATIONS 23Rebecca McDowell Cook (8/31/97)Secretary of State

Chapter 10—Underground Storage Tanks—Technical Regulations 10 CSR 20-10

department provides an extension of thetwelve (12)-month temporary closure period.Owners and operators must complete a siteassessment in accordance with 10 CSR 20-10.072 before such an extension can beapplied for.

AUTHORITY: sections 319.111, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990.

*Original authority: 319.111, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.071 Permanent Closure andChanges in Service

PURPOSE: This rule contains the require-ments for permanent closure of undergroundstorage tanks as well as for converting under-ground storage tanks to an unregulated use.

Editor�s Note: The secretary of state hasdetermined that the publication of this rule inits entirety would be unduly cumbersome orexpensive. The entire text of the material ref-erenced has been filed with the secretary ofstate. This material may be found at theOffice of the Secretary of State or at the head-quarters of the agency and is available to anyinterested person at a cost established bystate law.

(1) Owners and operators must notify thedepartment in writing, on forms provided bythe department, at least thirty (30) daysbefore beginning either permanent closure ora change in service of an underground storagetank (UST) in sections (2) and (3) of this ruleor within another reasonable time perioddetermined by the department, unless thisaction is in response to corrective action. Therequired assessment of the excavation zoneunder 10 CSR 20-10.072 must be performedafter notifying the department but beforecompletion of the permanent closure or achange in service.

(2) To permanently close a tank, owners andoperators must empty and clean it by remov-ing all liquids and accumulated sludges. Alltanks taken out of service permanently mustalso be either removed from the ground orfilled with an inert solid material.

(3) Continued use of a UST system to store anonregulated substance is a change in ser-vice. Before a change in service, owners andoperators must empty and clean the tank byremoving all liquid and accumulated sludge

and conduct a site assessment in 10 CSR 20-10.072.

(4) Owners and operators shall follow a writ-ten procedure. To comply with this rule, thedepartment�s UST Closure Guidance Docu-ment may be used as a written procedure. Itmay be supplemented with the followingcleaning and closure procedures:

(A) American Petroleum Institute Recom-mended Practice 1604, Removal and Dispos-al of Used Underground Petroleum StorageTanks;

(B) American Petroleum Institute Publica-tion 2015, Cleaning Petroleum StorageTanks;

(C) American Petroleum Institute Recom-mended Practice 1631, Interior Lining ofUnderground Storage Tanks; and

(D) Owners and operators may use otherwritten procedures with prior writtenapproval of the department.

AUTHORITY: sections 319.111, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990. Amended:Filed Aug. 3, 1993, effective April 9, 1994.

*Original authority: 319.111, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

24 CODE OF STATE REGULATIONS (8/31/97) Rebecca McDowell CookSecretary of State

10 CSR 20-10—NATURAL RESOURCES Division 20—Clean Water Commission

10 CSR 20-10.072 Assessing the Site atClosure or Change in Service

PURPOSE: This rule describes the require-ments of a site assessment, that is determin-ing whether there has been a release from theunderground storage tank system.

Editor�s Note: The secretary of state hasdetermined that the publication of this rule inits entirety would be unduly cumbersome orexpensive. The entire text of the material ref-erenced has been filed with the secretary ofstate. This material may be found at theOffice of the Secretary of State or at the head-quarters of the agency and is available to anyinterested person at a cost established bystate law.

(1) Before permanent closure or a change inservice is completed, owners and operatorsmust measure for the presence of a releasewhere contamination is most likely to be pre-sent at the underground storage tank (UST)site. In selecting sample types, sample loca-tions and measurement methods, owners andoperators must consider the method of clo-sure, the nature of the stored substance, thetype of backfill, the depth to groundwater andother factors appropriate for identifying thepresence of a release. The requirements ofthis section are satisfied if vapor monitoringor groundwater monitoring in 10 CSR 20-10.043(E) and (F) is operating at the time ofclosure and indicates no release has occurred.

(2) If contaminated soils, contaminatedgroundwater or free product as a liquid orvapor is discovered under section (1) of thisrule, or by any other manner, owners andoperators must begin corrective action in 10CSR 20-10.060�10 CSR 20-10.067.

(3) Owners and operators shall follow a writ-ten procedure. To comply with this rule, thedepartment�s UST Closure Guidance Docu-ment may be used as a written procedure.Other written procedures may be used withprior written approval of the department.

AUTHORITY: sections 319.111, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990. Amended:Filed Aug. 3, 1993, effective April 9, 1994.

*Original authority: 319.107, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.073 Applicability to Previ-ously Closed Underground Storage TankSystems

PURPOSE: This rule describes the responsi-bilities of owners and operators of under-

ground storage tanks closed before December22, 1988.

(1) The department may require that the own-er and operator of an underground storagetank (UST) system permanently closed beforeDecember 22, 1988, must assess the excava-tion zone and close the UST system in accor-dance with 10 CSR 20-10.070�10 CSR 20-10.074 if releases from the UST, in the judg-ment of the department, may pose a currentor potential threat to human health and theenvironment.

AUTHORITY: sections 319.111, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990.

*Original authority: 319.111, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

10 CSR 20-10.074 Closure Records

PURPOSE: This rule requires the owner andthe operator to keep records documenting theclosure and site assessment of undergroundstorage tank systems.

(1) Owners and operators must maintainrecords in accordance with 10 CSR 20-10.034 that are capable of demonstratingcompliance with closure requirements in 10CSR 20-10.070�10 CSR 20-10.074. Theresults of the site assessment in 10 CSR 20-10.072 must be maintained for at least three(3) years after completion of permanent clo-sure or change in service in one (1) of the fol-lowing ways:

(A) By the owners and operators who tookthe underground storage tank (UST) systemout of service;

(B) By the current owners and operators ofthe UST system site; or

(C) By mailing these records to the depart-ment if they cannot be maintained at theclosed facility.

AUTHORITY: sections 319.111, RSMo (Cum.Supp. 1989) and 644.026, RSMo (Cum.Supp. 1993).* Original rule filed April 2,1990, effective Sept. 28, 1990.

*Original authority: 319.111, RSMo (1989) and 644.026,RSMo (1972), amended 1973, 1987, 1993.

26 CODE OF STATE REGULATIONS (8/31/97) Rebecca McDowell CookSecretary of State

10 CSR 20-10—NATURAL RESOURCES Division 20—Clean Water Commission