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Hazardous Materials

What CERS Is

CERS, the California Environmental Reporting System, is the state's website for hazardous materials reporting. A business files its hazardous materials business plan there, updates it within 30 days of a change, and certifies it every year. Its local agency records inspections and violations in the same system. From 2020 through 2025, a business plan that was not certified on time was cited 64,643 times at 38,544 California sites.

By · Updated · 3 min read

CERS is the California Environmental Reporting System. It is a website run by CalEPA, at cers.calepa.ca.gov, and it is the “statewide information management system” that Health and Safety Code §25508 names when it says a business “shall electronically submit its business plan.”

Two kinds of users share it. A business uses the business portal to file and certify its hazardous materials business plan. The local CUPA uses the regulator portal to review those filings and to record its inspections, violations, and enforcement actions. That second use is what makes CERS a public record: the inspection data flows out to the CalEPA Regulated Site Portal, which is where the counts on this site come from.

What a business files in CERS

CERS presents the business plan as three sections, and CUPAs describe a submittal as complete when each has been submitted and accepted:

  • Facility information. The business, its location, owner and operator, and emergency contacts.
  • The hazardous materials inventory. Each material at or above the reporting threshold, with quantity, location, and hazard information.
  • Emergency response and training plans. The site map, the release response procedures, and the training plan, either entered in the system’s forms or uploaded as documents.

The contents are set by §25505(a). Some CUPAs require additional information by local ordinance, and CERS carries those local fields. Other Unified Program filings, including the tank facility statement for above-ground petroleum storage, go through the same portal.

The three deadlines

  • Within 30 days of becoming subject. Under §25508(b), a business “shall not be deemed to be in violation of this article until 30 days after the business becomes subject to” the filing requirement.
  • Within 30 days of a change. Under §25508.1, the plan must be updated within 30 days of certain changes; the CUPA violation record describes them as a 100% or more increase in a material, a new material, or a change in emergency contacts.
  • Every year, by the local due date or March 1. Under §25508.2, the owner, operator, or designated representative must “annually review and certify that the information in the statewide information management system is complete, accurate, and in compliance.” A full submittal satisfies it. The due date is the one the CUPA sets, or March 1 (§25508(a)(2)).

The plan itself is resubmitted annually by facilities that file federal Tier II information or hold above-ground petroleum tanks, and every three years by everyone else (§25508(a)(1)). The annual certification applies to all.

The certification is the second most cited item

From 2020 through 2025, a business plan that was not reviewed and certified on time was cited 64,643 times at 38,544 California sites, under two code sections, and 27% of those sites were cited for it in two or more different years. It is the second most cited item at California hazardous materials inspections, behind only the site map. The typical time from citation to correction was 28 days under §25508.2 and 37 days under §25508(a)(1), per the return-to-compliance dates the CUPAs record. The most cited CUPA violations has the full table.

Help with CERS

CalEPA runs a help section inside CERS and publishes guidance on the Hazardous Materials Business Plan program page. Some CUPAs run help desks for submittals. The local agency sets the due date and accepts the filing, so it is the first place to ask. CERS itself is at cers.calepa.ca.gov.

Hazardous materials in California

Sources

Statutory text is quoted from the California Health and Safety Code as published by the Legislature on September 10, 2026: §25505, §25508, and §25508.2. Violation counts are computed by CompliantCA from the CalEPA Regulated Site Portal export of September 10, 2026, for Unified Program records dated 2020 through 2025; the method is on the most cited violations page.

This page describes the system and what the statute requires of it. The local CUPA sets the due date for a given facility and answers whether a filing is required.

Frequently asked questions

What is CERS?

CERS is the California Environmental Reporting System, run by CalEPA at cers.calepa.ca.gov. It is the statewide information management system that Health and Safety Code §25508 requires a business to use to file its hazardous materials business plan electronically. Local CUPAs use the same system to record inspections, violations, and enforcement.

What is the CERS annual certification?

Health and Safety Code §25508.2 requires the business owner, operator, or designated representative to review the facility's information in CERS every year and certify that it is complete, accurate, and in compliance with the federal reporting requirement. It is due on the date the local CUPA sets, or by March 1. A full electronic submittal of the plan satisfies the certification.

What is a CERS submittal?

A submittal is the act of sending one or more sections of the business plan to the local CUPA through CERS: facility information, the hazardous materials inventory, and the emergency response and training plans. The CUPA reviews and accepts each section. Under §25508(a)(3), if the CUPA finds the plan deficient, a corrected submittal is due within 30 days of the notice.

How often is a business plan not certified in CERS?

From 2020 through 2025, California CUPAs cited a missing annual certification 64,643 times at 38,544 sites, under Health and Safety Code §25508(a)(1) and §25508.2, per the CalEPA Regulated Site Portal. 27% of those sites were cited for it in two or more different years. The typical time from citation to correction was 28 to 37 days.

Continue reading

  • What a Hazardous Materials Business Plan Is Health and Safety Code §25507 requires a hazardous materials business plan of a California business that handles 55 gallons of a hazardous liquid, 500 pounds of a solid, or 200 cubic feet of a gas at one time, with exemptions the section lists. What the plan contains, when it is due, and what inspectors cite most: the site map, the certification, and the training record.
  • What a CUPA Is A CUPA is a Certified Unified Program Agency: the county or city department, usually environmental health or the fire department, that CalEPA certifies to inspect businesses for hazardous materials business plans, hazardous waste, and fuel tanks. 101 agencies recorded inspections from 2020 through 2025; 38% found a violation.
  • Most Cited CUPA Violations in California, 2020–2025 The violations California's local hazardous materials agencies cited most from 2020 through 2025, computed from 624,254 violations in the CalEPA Regulated Site Portal. The top four are a missing site map, an uncertified business plan, and a missing training record. Typical fix time is 41 days.
  • The CalEPA Regulated Site Portal The CalEPA Regulated Site Portal is the public map of every site California regulates for hazardous materials, with each site's inspections, violations, and enforcement actions. What it holds, 264,785 sites and 624,254 violations from 2020 through 2025, how to look up a business, and what the record does and does not mean.

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