Here are some references from RAGS A, Chapter 6:
Exhibit 6-11, Residential Exposure: Ingestion of Chemicals in Drinking Water
Exhibit 6-12, Residential Exposure: Ingestion of Chemicals in Surface Water While Swimming
Exhibit 6-13, Residential Exposure: Dermal Contact with Chemicals in Water
Exhibit 6-14, Residential Exposure: Ingestion of Chemicals in Soil
Exhibit 6-15, Residential Exposure: Dermal Contact with Chemicals in Soil
Exhibit 6-16, Residential Exposure: Inhalation of Airborne (Vapor Phase) Chemicals
Exhibit 6-17 Residential Exposure: Food Pathway - Ingestion of Contaminated Fish and Shellfish
Exhibit 6-18 Residential Exposure: Food Pathway - Ingestion of Contaminated Fruits and Vegetables
Exhibit 6-19 Residential Exposure: Food Pathway - Ingestion of Contaminated Meat, Eggs, and Dairy Products
How many of these will you need? Answer. At least one for each completed exposure pathway.
How do you know there is a completed exposure pathway? Answer. You figured that out when you did your SCEM.
The above will help you define the parameters you need to complete the Intake Assessment and close out the exposure assessment. The above provides a few parameters, but not most. The authoritative document on those factors is the EPA's Exposure Factors Handbook NEXT