Los Altos Hills Municipal Code Art. 3 Containment Standards

No person, firm or corporation shall store any hazardous materials regulated by this chapter until a permit or approval has been issued pursuant to this chapter. No permit or approval shall be granted pursuant to this chapter unless permit applicant demonstrates to the satisfaction of the officer, by the submission of appropriate plans and other information, that the design and construction of the storage facility will result in a suitable manner of storage for the hazardous material or materials to be contained therein.

All installation, construction, repair or modification, closure, and removal shall be to the satisfaction of the officer. The officer shall have the discretion to exempt an applicant from any specific requirement, except that the discretion with regard to underground storage facilities shall be exercised in accordance with Section 4-8.302(c)(4) or to impose reasonable additional or different requirements in order to better secure the purpose and general obligation of this chapter for protection of public health, safety, and welfare. The guidelines approved pursuant to Section 4-8.1302 shall serve as an interpretation of the provisions of this article addressed in such guidelines.

(Added by Ord. 284, § 2)

(a) No person, firm or corporation shall construct or install any new storage facility until a permit or approval has been issued pursuant to this chapter.

(b) Monitoring Capability. All new storage facilities intended for the storage of hazardous materials which are liquids or solids at standard temperature and pressure (STP) shall be designed and constructed with a monitoring system capable of detecting that the hazardous material stored in the primary containment has entered the secondary containment. Visual inspection of the primary containment is the preferred method; however, other means of monitoring may be required by City. Where secondary containment may be subject to the intrusion of water, a means of monitoring for water intrusion and for safely removing the water shall also be provided.

Whenever monitoring devices are provided, they shall, where applicable, be connected to attention-getting visual and/or audible alarms.

(c) Containment Requirements. Primary and secondary levels of containment shall be required for all new storage facilities intended for the storage of hazardous materials which are liquids or solids at standard temperature and pressure (STP) unless exempted by the officer.

(1) All primary containment shall be product-tight.

(2) Secondary containment:

(i) All secondary containment shall be constructed of materials of sufficient thickness, density, and composition so as not to be structurally weakened as a result of contact with the discharged hazardous materials and so as to be capable of containing hazardous materials discharged from a primary container for a period of time equal to or longer than the maximum anticipated time sufficient to allow recovery of the discharged hazardous material.

(ii) In the case of an installation with one primary container, the secondary containment shall be large enough to contain at least 110% of the volume of the primary container.

(iii) In the case of a storage facility with multiple primary containers, the secondary container shall be large enough to contain 150% of the volume of the largest primary container placed in it, or 10% of the aggregate internal volume of all primary containers in the storage facility, whichever is greater.

(iv) If the storage facility is open to rainfall, then the secondary containment must be able to additionally accommodate the volume of a 24 hour rainfall as determined by a on hundred (100) year storm history.

(3) Laminated, coated, or clad materials shall be considered single-walled and shall not be construed to fulfill the requirements both primary and secondary containment.

(4) Variance Secondary Containment.

(i) A variance from the requirement for secondary containment for an underground storage facility may be granted upon written finding by the officer issuing the permit, which has been reviewed and approved by the City Council of the City that based on the special circumstances:

a. The requirement of secondary containment creates an unusual and particular hardship; and

b. An equivalent degree of protection is provided by the proposed alternative; and

c. The proposed alternative has been appropriately so certified as providing an equivalent degree of protection, by an independent consultant retained in accordance with Section 4-8.105, or has been specified as potentially appropriate for a variance in the guidelines approved pursuant to Section 4-8.1302.

(ii) The City Council shall consider the variance, at a public meeting, at which oral or written presentation on the matter may be made. A notice which includes a statement that a variance from secondary containment for hazardous materials will be considered, and which specifies the address of the facility seeking the variance, and the time and place of the meeting shall be given in the following manner:

a. The City Clerk of the City shall cause a copy of the notice to be published once in a newspaper of general circulation in the County, not less than 10 days prior to the meeting; and

b. The City Clerk shall cause a copy of the notice to be mailed at least 10 days prior to the meeting to any party who files a written request with the City Clerk, for mailed notice of meetings at which such variance is to be considered. Such written request for notice shall be valid for one year from the date on which it is filed unless a renewal request is filed. Renewal request for such mailed notices shall be filed on or before April 1st of each year.

(5) Variance—Construction and Monitoring Requirements. Underground storage tanks may be granted a variance from the standards for construction and monitoring set forth in this article other than from the requirement for double containment, only upon written finding by the officer issuing the permit that the applicant has demonstrated by clear and convincing evidence:

(i) That because of special circumstances not generally applicable to other property or facilities, including size, shape, design, topography, location, or surroundings, the strict application of the standards of this chapter would be unnecessary to adequately protect the soil and beneficial uses of the waters of the State from an unauthorized release; or

(ii) That strict application of the standards of this chapter would create practical difficulties not generally applicable to other facilities or property; and that the proposed alternative will adequate! protect the soil and beneficial uses of the waters of the state from a unauthorized release.

(d) Overfill Protection. Means of overfill protection may be required for any primary container. This may be an overfill prevention device and or an attention-getting high level alarm.

(e) Separation of Materials. Materials that in combination may cause afire or explosion, or the production of a flammable, toxic, or poisonous gas, or the deterioration of a primary or secondary container shall be separated in both the primary and secondary containment so as to avoid potential intermixing.

(f) Drainage System. Drainage of water entering by precipitation or infiltration from within a storage facility containing hazardous materials which are liquids or solids at STP shall be controlled in a manner approved by the City so as to prevent hazardous materials from being discharged. No drainage system will be approved unless the flow of the drain can be controlled. The facility shall contain a means of removing the water by the owner or operator. This removal system shall also provide for a means of analyzing the removed water for hazardous substance contamination and a means of disposing of the water, if so contaminated, at an authorized disposal facility.

(Added by Ord. 284, § 2 (part); amended by Ord. 287, § 2)

Any storage facility in existence as of the effective date of this chapter, or any storage facility for which a building permit was issued prior to the effective date of the ordinance codified in this chapter, which does not meet the standards of Section 4-8.302, may be permitted pursuant to this chapter as long as it is providing suitable storage for hazardous materials. The owner shall outfit the facility with a monitoring system capable of detecting unauthorized releases of any hazardous substances stored in the facility, and thereafter the operator shall monitor each facility, based on the materials stored and the type of monitoring installed. In addition, storage facilities which contain hazardous materials which are liquids or solids at standard temperature and pressure (STP) must be monitored in accordance with a plan approved by City as set forth herein.

(a) A monitoring plan for each such storage facility containing hazardous materials which are liquids or solids at STP, shall be submitted to the officer as part of the hazardous materials management plan

(b) Monitoring under such plan shall include visual inspection of the primary containment wherever practical; however, if the visual inspection is not practical, an alternative method of monitoring each storage facility on a monthly or more frequent basis may be approved by the City.

(c) Alternative method(s) of monitoring may include but are not limited to: pressure testing, vacuum testing or hydrostatic testing of the piping systems or underground storage tanks; groundwater monitoring well(s) which are downgradient and adjacent to the storage facility; vapor analysis within the well(s) where appropriate; and analysis of the soil boring(s) at the time of initial installation of the well(s). The location and number of well(s), depth of well(s), and sampling frequency shall be approved by the City.

(d) Such monitoring devices and methods, as approved by the City, shall be installed and operating within six months of the issuance of a provisional permit in accordance with Section 4-8.805 and any other applicable provisions of this chapter. The City may grant an extension of this compliance date; however, such extension shall not exceed one additional year. The full term permit may be issued when compliance with this subsection has been achieved. No monitoring systems required by this section shall be installed later than January 1, 1985, or the date specified in Section 25284.1 of Chapter 6.7 of Division 20 of the Health and Safety Code, whichever date is later.

(e) The continued use of, and permit approval for, existing storage facilities is subject to review and modification or termination by the officer whenever there has been any unauthorized discharge. It shall also be reviewed by the officer each time the permit is renewed. In determining whether continued storage in such storage facility is suitable, the officer shall consider the age of the storage facility, the methods of containment, the methods of monitoring, the feasibility of the required retrofit, the concentration of the hazardous materials contained, the severity of potential unauthorized discharge, and the suitability of other long term preventive measures which meet the intent of this chapter.

(f) Existing storage facilities which are not approved in accordance with this section must be upgraded to comply with this chapter or be closed in accordance with Section 4-8.304 within one year of a decision not to issue a full term permit. An extension of time for compliance with this subsection, not to exceed one additional year, may be granted.

(Added by Ord. 284, § 2 (part); amended by Ord. 287, § 3)

(a) No storage facility shall be abandoned.

(b) Storage facilities which are temporarily out of service, and are intended to be returned to use, must continue to be monitored an inspected.

(c) Any storage facility which is not being monitored an inspected in accordance with this chapter must be closed or removed in manner approved by the officer in accordance with Section 4-8.808.

(d) Any person, firm or corporation having an interest, including a leasehold interest, in real property and having reason to believe that an abandoned storage facility is located upon such property shall make a reasonable effort to locate such storage facility within six months old the effective date of this chapter.

(e) Whenever an abandoned storage facility is located, a plan for the closing or removing or the upgrading and permitting of such storage facility shall be filed within 90 days of its discovery. A closure plan shall conform to the standards specified in Section 4-8.808.

(Added by Ord. 284, § 2)

(a) Monitoring Methods. Monitoring methods shall include at least one system for detecting leakage from the primary container. A monitoring system, capable of detecting that the hazardous material stored in the primary containment has entered the secondary containment, shall be provided. Visual inspection of the primary containment is the preferred method; however, other means of monitoring may be required. Where secondary containment may be subject to the intrusion of water, a means of monitoring for such water shall be provided.

Whenever monitoring devices are provided, they shall, where applicable, be connected to attention-getting visual and/or audible alarms.

(b) Monitoring, Testing and Inspection. Every permittee under this chapter shall provide testing, monitoring (if applicable), and inspections in compliance with the hazardous materials management plan and shall maintain records adequate to demonstrate compliance therewith.

(Added by Ord. 284, § 2)

(a) Permittee will carry out maintenance, ordinary upkeep, and minor repairs in a careful and safe manner. No permit or other approval will be required for such maintenance and upkeep.

(b) Any substantial modification or repair of a storage facility other than minor repairs or emergency repairs shall be in accordance with plans to be submitted to the officer and approved in accordance with this chapter prior to the initiation of such work.

(c) Permittee may make emergency repairs to a storage facility in advance of seeking an additional permit approval whenever a immediate repair is required to prevent or contain an unauthorized discharge or to protect the integrity of the containment. However, within five working days after such emergency repairs have been started permittee shall seek approval pursuant to this chapter by submitting drawings or other information adequate to describe the repairs to the officer.

(d) Replacement of any storage facility for hazardous materials, which are liquids or solids at STP, must be in accordance with the new installation standards of Section 4-8.302.

(Added by Ord. 284, § 2)

(a) Dispensing and mixing of hazardous materials must not be done in such a manner as to substantially increase the risk of an unauthorized discharge.

(b) When hazardous materials are moved into or out of a storage facility, they shall remain in the travel path only for the time reasonably necessary to transport the hazardous material and such movement shall be in a manner which will not result in an unauthorized discharge.

(Added by Ord. 284, § 2)

Access to the storage facilities shall be secured by means of fences and/or locks. The access to the storage facilities shall be kept securely locked when unattended.

(Added by Ord. 284, § 2)

Emergency equipment shall be provided which is reasonable and appropriate for potential emergencies presented by the stored hazardous materials. Such equipment shall be regularly tested and adequately maintained.

(Added by Ord. 284, § 2)

Simplified emergency procedures shall be posted conspicuously in locations where hazardous materials are stored.

(Added by Ord. 284, § 2)