BAYTOWN, Texas (AP) _ Dianne Branan, her two daughters and four grandchildren say they have put up with vomiting, headaches and diarrhea for years.

Then, about two weeks ago a pungent black goo began appearing in a hole in her back yard.

``All summer people have asked me if I had a gas leak because it smelled so,'' said Mrs. Branan, who has lived in the house for 17 years. ``I'm always sick.''

Mrs. Branan lives across the street from the playground of G.W. Carver Elementary school, where a similar smelly tarlike substance was discovered June 29. Some of her close neighbors also say they have found the goo in their yards.

It is long forgotten _ if known at all by some residents _ that Carver Elementary was built in 1946 atop a former oil storage pit _ on land donated by Humble Oil Co., which evolved into Exxon.

Travel down Mrs. Branan's street and residents recall intestinal problems and miscarriages, cancers and cysts, the causes of which are unknown and have not been connected to the oil.

Moments after examining the severely deformed face of her newly born son, Zachary, in 1992, doctors asked Mrs. Branan's neighbor Angela Parker a chilling question.

``They asked were we exposed to any chemicals or toxic waste,'' Mrs. Parker recalls. She told them no and until now wrote off Zachary's deformity to a gene anomaly that has not been linked to any real cause.

``You just have to wonder,'' said Mrs. Parker, who has been a neighbor of Mrs. Branan since 1984. ``It scares me.''

Mrs. Parker and the neighborhood want to know whether the illnesses are connected with the oily residue. So far, there are no definitive answers.

Gravity and heat are believed to have brought oil residue from the pit to the surface at the school, officials said. As a precaution, all 814 students at Carver will go to other schools beginning today until cleanup can be completed, some two months from now.

Exxon is paying for the cleanup, at least $200,000. While company officials acknowledge the oil at the school, they said there is no proof that it spread elsewhere.

Some residents, however, want Exxon to test the soil in the area outside the school grounds.

``Our position at this time _ because we have not detected anything from the initial area _ is that there's not sufficient reason to test further,'' said Jan Adelman, an Exxon spokesman.

Exxon would not discuss the illnesses in the neighborhood.

Weathered oil residue is not thought to be a problem because most of the properties in crude oil evaporate over time, soil experts said.

However, other components if found, do pose a threat, said Marvin Legator, who heads the environmental toxicology division at the University of Texas Medical Branch at Galveston.

``I would bet you that going to the 30s and 40s, the oil storage tanks contained a number of petroleum related products,'' Legator said. Some of those products such as xylene and benzene have been connected to cancers, birth defects and neurological disorders, he said.

Whether the pit contained those substances is not known. As of Thursday, Exxon had no report indicating that those substances had been detected.

Baytown, about 15 miles from Houston, is no stranger to strange smells or chemicals. The town of 60,000 is home to a huge Exxon complex that houses one refinery, two chemical plants and two research centers.

The original pit, built by Texaco in 1917, was placed about 5- to 9-feet deep with a hard clay bottom serving as the only container.

Humble bought the pit in 1920 and operated it until 1930. In 1940 the first parcel of land was donated to the school district. The oil pit was drained before it was buried, Exxon said.

There is evidence that some of the oil remnants seeped down to 12- to 14-feet deep, said Ron Embry, another Exxon spokesman. However, there is no evidence it spread elsewhere, he said

He hesitated to speculate on the goo found by Mrs. Branan.

``I can tell you that there are many places that oil can come from,'' Embry said. ``One place is the oil drained from automotive vehicles.''