Members of Connecticut’s congressional delegation and Massachusetts Rep. Richard Neal want $4 million set aside so an iron sulfide that has caused homeowners’ foundations in both states to crumble can be researched.

Thousands of homes in Connecticut and and unknown number in Massachusetts are affected by the problem, which stems from contaminated gravel sold by a now-closed Connecticut quarry. So far, Connecticut has seen $100 million in claims filed with a captive insurance company set up to help homeowners fix their properties, and more claims are likely in the offing.

The Democrats last week sent a letter to House Appropriations Committee leaders, urging them to support a year-end spending package that retains the full level of $4 million for the National Institute of Standards and Technology (NIST) to conduct the research on pyrrhotite. The Senate has passed a package with $1.5 million.

Connecticut Rep. Joe Courtney in June offered an amendment seeking the $4 million, noting that much money is needed to develop a cost-effective and standard testing method. NIST would also be required to create a risk-rating scale to determine how much pyrrhotite poses a danger.