Web Services

Envirofacts has developed web services to facilitate the sharing of its functionality and information. All of the services that are available within Envirofacts are listed below.

A RESTful data service API is available for Envirofacts UV Index Hourly and Daily forecast data.

The entire Envirofacts database metadata is available online, with all tables and columns within Envirofacts documented. Having the table structures available in this manner makes most of Envirofacts data easily available through the services. Logical data models for use in the Envirofacts APIs, are available at the Envirofacts data model page. This page contains links to all of the EPA systems and data models contained within Envirofacts.

GraphQL API

The DMAP API is a GraphQL-like API that is available to access data within Envirofacts. This API provides the ability to create more complex queries than the RESTful API below. Documentation for the API is available at the DMAP GraphQL API Overview.

Envirofacts RESTful Data Service API

Envirofacts has developed a RESTful data service API for all its internal data holdings. This functionality provides an Envirofacts user with the ability to query any table via an URL. The default output is in JSON. Additional output options of CSV, Excel, HTML, JSONP, Parquet, PDF, and XML can be requested in the URL.

Strengths and Limitations of the Envirofacts RESTful Service

The Envirofacts REST Service is simple and easy to use to access multiple data sources within EPA. The resulting output formats can be easily used with desktop applications such as Excel or used in other custom applications.

The service currently limits to requests to being completed in under 15 minutes. If more data is needed than this, users can page through the data, requesting the next set of records in the table.

Constructing a Search

To build a search, users create a URL with a specific set of parameters. This is done by creating a string using the following format:

https://data.epa.gov/efservice/[table]/[column][operator][value]/[join]/[first]:[last]/[sort]/[format]

Table

Required. At least one table name is required. When inserting multiple tables into the URL, they must share an ID or common column, so that the tables can be joined or linked. To retrieve an accurate output, it is best to use tables that share an ID column. For example, within the RCRAInfo tables, they often share an ID column called handler_id.

The table name must match the format [program].[table]. The program is the schema or acronym to which the table belongs, e.g., SEMS, RCRA, GHG, TRI. The table is the name of the table in the database. As an example, to query the table "ogd_vw_ef_base" in the NGGS program, the table entry would be nggs.ogd_vw_ef_base.

Filter

To filter the records returned in the query, one or more filters can be applied to a query. The filter must be in format: [column][operator][value]. The column attribute is the table column that will be compared in the filter. The operator is a symbol that will be the basis for the comparison, e.g., equals, not equals, greater than, etc. The list of operators with descriptions is: "equals", "notEquals", "lessThan", "lessThanEqual", "greaterThan", "greaterThanEqual", "beginsWith", "endsWith", "contains", "excludes", "like", "notLike", "in", and "notIn". The value attribute is what the column will be compared against. Operators can be combined using the /and/, which requires both filters to be met, and /or/, which requires either one of the filter's criteria to be met.

As an example, to restrict a query of the NEI facilities in the 2017 summary data to those in Houston, TX, this filter would work: state_code/equals/TX/and/city_name/equals/Houston. When filter operations are performed on text fields, the comparison is case-insensitive.

Join

Combine results from two tables using the available join types. The format is like a table and filter combination: [join_type]/[table]/[comparison]. The join value is the appropriate join type. The table is the table that should be joined, matching the structure of the table value above. Finally, the (optional) comparison is structured the same as the filter above, just comparing two table columns.

As an example, to include contaminants in a SEMS query of sites, /sems.envirofacts_site/left/sems.envirofacts_contaminants/site_id/equals/fk_site_id would perform a left join and include data from the envirofacts_contaminants table.

First

The first record to retrieve, starts at 1.

Last

The last record to retrieve.

Order

Sort the fields in the results. The format for applying a sort is /sort/[column]:[direction]/. The column is the field that needs to be sort . The direction is optional and can either be asc or desc. "asc" means the field will be sorted in ascending order. "desc" means the field will be sorted in descending order. If no direction is supplied, "asc" will be used as the default sort direction.

Format

The export format, e.g., JSON, JSONP, CSV, Excel, HTML, Parquet, PDF, and XML. The default format is JSON.

For example:

• https://data.epa.gov/efservice/tri.tri_facility/state_abbr/equals/VA/500:505
  returns result set records 500 to 505 from the TRI Facility table where state_abbr = 'VA'.
• https://data.epa.gov/efservice/icis.icis_comp_monitor/comp_monitor_category_code/equals/ALT/sort/created_date/1:100000
  returns the first 100,000 records from ICIS icis_comp_monitor table where the comp_monitor_category_code = “ALT”. The records will be sorted by the created_date field in ascending order.
• https://data.epa.gov/efservice/tri.tri_facility/state_abbr/equals/HI/join/tri.tri_reporting_form
  returns results from the TRI Facility and TRI Reporting Form tables where the state is HI in the TRI Facility table.
• https://data.epa.gov/efservice/tri.tri_reporting_form/join/tri.tri_facility/state_abbr/equals/VA/join/tri.tri_chem_info/excel
  returns results from the TRI Facility, TRI Reporting Form and TRI Chem Info tables where the state is VA in the TRI Facility table in Excel format .
• https://data.epa.gov/efservice/tri.tri_facility/zip_code/beginsWith/600/JSON
  returns results from the TRI Facility table where zip_code "Begins With" 600 in a JSON format.
• https://data.epa.gov/efservice/tri.tri_facility/state_abbr/equals/VA/CSV
  returns result from the TRI Facility table where state_abbr = 'VA'in a CSV format.

More information on EF Data Service API

View documentation for the EF Data Service API v1.

UV Index

Envirofacts provides two approaches for retrieving UV Index data thru web services: a RESTful data service API and a SOAP (Simple Object Access Protocol) web service. The information is searchable by ZIP Code and city, state, making it useful for any organization, either local or national. Users do not have to leave your site to see the forecast. The UV Index Overview provides additional information on the data. Both approaches are detailed below.

RESTful Data Service API

This functionality provides a user of UV Index data, within Envirofacts, the ability to query daily or hourly forecast data through the use of a URL. The four APIs for retrieving UV Index forecast information are:

• Get the Hourly UV Index forecast by ZIP Code
• Get the Hourly UV Index forecast by City and State
• Get the Daily UV Index forecast by ZIP Code
• Get the Daily UV Index forecast by City and State

Get the Hourly UV Index forecast by ZIP Code

Get the Hourly UV Index forecast by City and State

Get the Daily UV Index and Alert forecast by Zip Code

Get the Daily UV Index and Alert forecast by City and State