AB2588 reporting has not really changed since 1987.
The data, the SDOH layer, and the workflow have.

AB2588 is California's Air Toxics "Hot Spots" Information and Assessment Act, passed in 1987. It requires industrial facilities to report their air toxics emissions to their local air pollution control or air quality management district, and it requires high priority facilities to prepare a Health Risk Assessment showing the cancer and non-cancer risk those emissions create for surrounding receptors. The program is administered jointly by CARB, OEHHA, and the local air districts (SCAQMD, BAAQMD, SJVAPCD, SBCAPCD, NCUAQMD, and others). Facilities that exceed a district's notification threshold must also notify the affected public.

AB2588 requires every facility above the program reporting threshold to submit an emissions inventory to its local air district. The district then ranks each facility as low, intermediate, or high priority based on the prioritization score, which combines pollutant toxicity, emission rates, and distance to the nearest receptor. Facilities ranked high priority must prepare a Health Risk Assessment using OEHHA-approved methodology. Intermediate facilities may be asked for additional information, and low priority facilities are typically exempt from the HRA step until their next inventory cycle.

The official CARB tool is HARP2, the Hotspots Analysis and Reporting Program. HARP2 is a free Windows desktop application built on the .NET Framework 4.7.2 and contains three modules: the Emissions Inventory Module (EIM), the Air Dispersion Modeling and Risk Tool (ADMRT), and the Risk Assessment Standalone Tool (RAST). Districts review submissions against the OEHHA 2015 methodology that HARP2 implements. LSARS reproduces the same OEHHA 2015 methodology and is parity-validated against HARP2 to five significant figures, so the calculation a district reviewer expects to see is the calculation LSARS produces.

High priority facilities under AB2588 are generally required to update their Health Risk Assessment on a roughly four-year cycle, with the exact schedule set by the local air district's reporting program. Districts can also require an updated HRA outside of that cycle if a facility changes its operations, adds new equipment, or if the underlying methodology is revised by OEHHA. Because the cycle repeats, multi-facility operators benefit from a system that can re-run the HRA against updated emissions and updated SDOH context without rebuilding the model from scratch each time.

MEIR is the Maximum Exposed Individual Resident, the modeled receptor location with the highest residential cancer risk from a facility's emissions. MEIW is the Maximum Exposed Individual Worker, the equivalent for an offsite worker receptor. AB2588 HRAs report both metrics, along with the chronic Hazard Index (HIC) and acute Hazard Index (HIA), because residential and worker exposure assumptions differ in duration, breathing rate, and Age Sensitivity Factor weighting. LSARS computes all four and shows the contributing pollutants and source groups behind each number.

AB2588 itself is a California statute, so the prioritization step and the district notification process are specific to California air districts. The underlying OEHHA 2015 methodology, however, is widely used outside California for permit-grade Health Risk Assessment work, and EPA AirToxScreen 2020 methodology covers similar ground at the federal level. LSARS supports both methodologies and 50-state coverage, so the same engine that handles a California AB2588 HRA can also handle Title V, NEPA, or state-equivalent HRA work elsewhere.

A full AB2588 lifecycle has four to five distinct phases: emissions inventory submittal to the district, prioritization scoring by the district, Health Risk Assessment if the facility lands as high priority, public notification if risks exceed the district's notification threshold, and a Risk Reduction Plan if risks exceed the action threshold. LSARS treats these as connected phases of one workflow rather than separate one-off projects, so updated emissions data flows into the HRA, the HRA feeds the notification report, and the audit trail follows the facility across reporting cycles.

No. HARP2 is the official CARB tool, and districts review against the OEHHA methodology HARP2 implements. LSARS does not replace HARP2 in the regulatory sense. What LSARS does is reproduce the same OEHHA 2015 methodology to five significant figures, add the SDOH overlay and audit trail HARP2 was never built for, and give multi-facility operators and consulting teams a workflow that fits modern iteration cycles. The responsible party for a submission is always the facility or its consultant.